Light-accumulating material, light-accumulating particles, dispersion liquid, and display medium

Abstract

The present invention provides a light-accumulating material which exhibits room temperature phosphorescence in a red region or a near-infrared region, wherein the phosphorescence has a long lifetime and high luminance. The present invention specifically provides a light-accumulating material that contains a compound in which a group 16 element X1 of the periodic table is directly bonded to a polycyclic aromatic skeleton or a cyclic skeleton that is bonded to a polycyclic aromatic skeleton via an element X2 that is selected from among S, P, N, and Si (wherein the element X1 may form a ring together with other elements, but in this case, the ring is constituted by bonding only X1 and carbon C).

Description

Luminous material, luminous particles, dispersion, and display medium

[0001] The present invention relates to a luminous material, a dispersion liquid, and a display medium.

[0002] Phosphorescence is a phenomenon in which a substance absorbs irradiated light, stores the light as energy, and continues to emit light for a while even after the light irradiation has stopped. Until now, inorganic compounds have been known as materials that exhibit phosphorescence at room temperature, but organic compounds have also been proposed. Phosphorescence in organic compounds is mainly a phenomenon called phosphorescence, which is defined as light emission based on a spin-forbidden transition from an excited triplet state to a ground singlet state.

[0003] In recent years, many organic compound materials that exhibit long-lifetime room-temperature phosphorescence (e.g., an emission lifetime of 100 milliseconds (ms) or more) have been reported. Compared to the phosphorescence of existing phosphorescent materials that use charge separation and subsequent recombination, such long-lifetime room-temperature phosphorescence can increase the intensity of excitation light and exhibit greater phosphorescent brightness immediately after the irradiation of the excitation light is stopped. Therefore, with regard to such long-lifetime room-temperature phosphorescence, the afterglow that momentarily occurs in a bright environment can be easily seen, and examples of its application to anti-counterfeiting media have been reported (Non-Patent Document 1).

[0004] In addition, various molecules that exhibit long-life room-temperature phosphorescence or solid materials using such molecules have been reported.

[0005] For example, Non-Patent Document 2 reports a material using a deuterated molecule in which an aromatic amine group is attached as a substituent to a naphthalene skeleton, which has a phosphorescence spectrum with a peak wavelength in the yellow region, a room-temperature phosphorescence quantum yield (which is, in other words, an index of brightness) of 50%, and an average phosphorescence lifetime of 1.0 s. Furthermore, Non-Patent Document 2 takes advantage of the characteristic that long-life room-temperature phosphorescence can exhibit greater brightness compared to the phosphorescence of existing phosphorescent materials, and claims that it is possible to measure small objects of 10 μm or less with high resolution using a two-dimensional photodetector immediately after irradiation with excitation light is stopped, without relying on surrounding fluorescent impurities.

[0006] Furthermore, Non-Patent Document 3 reports a material using a molecule in which a plurality of carbonyl groups are directly attached as substituents around a benzene skeleton, the material having a phosphorescence spectrum with a peak wavelength in the blue region, a room temperature phosphorescence quantum yield of 100%, and an average phosphorescence lifetime of 100 ms.

[0007] Furthermore, Non-Patent Document 4 reports a material using a molecule in which carbonyl groups are attached as substituents around a coronene skeleton, the material having a phosphorescence spectrum with a peak wavelength in the yellow region, a room temperature phosphorescence quantum yield of 21%, and an average phosphorescence lifetime of 2.1 s.

[0008] Furthermore, Non-Patent Document 5 reports a solid material in which a benzo[b]phenothiazine derivative is dispersed, which has a phosphorescence spectrum with a peak wavelength in the orange region (approximately 590 nm), a room temperature phosphorescence quantum yield of 30%, and an average phosphorescence lifetime of 0.14 s.

[0009] Furthermore, Non-Patent Document 6 reports a material using a pyrene molecule and a molecule having an aromatic amine group attached as a substituent around the pyrene skeleton, which has a phosphorescence spectrum with a peak wavelength in the red region and exhibits a room-temperature phosphorescence quantum yield of up to 9.4% and an average phosphorescence lifetime of 0.34 s.

[0010] Furthermore, as phosphorescent materials whose phosphorescence spectrum has a peak wavelength in the red region, a material using a molecule in which a deuterated dibenzo[gq]chrysene skeleton is substituted with a phenoxazine group (Non-Patent Document 7), a solid material in which an aromatic compound is dispersed (Non-Patent Document 8), etc. have also been reported. In addition, a phosphorescent material whose phosphorescence spectrum has a peak wavelength in the red region is also disclosed in Non-Patent Document 9.

[0011] Appl. Phys. Rev. 2022, 9, 011304.Adv. Mater. 2020, 32, 2001348.Nat. Mater. 2021, 20, 1539.Angew. Chem. Int. Edit. 2020, 59, 9393.J. Mater. Chem. C 2023 11, 4846.Nat. Commun. 2022, 13, 186.J. Phys. Chem. Lett. 2022, 13, 7788.Chem. Commun. 2023, 59, 7036.Bahadur Sk, Shuzo Hirata, Advanced Science, 2308897

[0012] Regarding phosphorescent materials having peak wavelengths in the blue to yellow region (approximately 430 to 585 nm), molecules with a long average phosphorescence lifetime of 100 ms or more and a high room-temperature phosphorescence quantum yield (for example, 50% or more) have been reported, as disclosed in Non-Patent Documents 2 to 4. Furthermore, regarding phosphorescent materials having peak wavelengths of approximately 590 nm, molecules with a long average phosphorescence lifetime of 100 ms or more and a high room-temperature phosphorescence quantum yield of 30% have been reported, as disclosed in Non-Patent Document 5.

[0013] On the other hand, in the reports so far, as shown in Non-Patent Documents 6 to 8, regarding materials that emit phosphorescence with a peak wavelength in the red or near-infrared region (e.g., 600 nm or longer), even if the average phosphorescence lifetime is as long as 100 ms or longer, the room-temperature phosphorescence quantum yield in such cases is low.

[0014] Materials (phosphorescent materials) that exhibit room-temperature phosphorescence in the red or near-infrared region and have a long life and a high room-temperature phosphorescence quantum yield are considered promising for use, for example, in imaging deep inside living organisms with high contrast and high resolution without relying on autofluorescence, and their development is desired.

[0015] Therefore, an object of the present invention is to provide a phosphorescent material that exhibits room-temperature phosphorescence in the red or near-infrared region, and that has a long life and high brightness. Another object of the present invention is to provide phosphorescent particles, a dispersion, and a display medium using the phosphorescent material.

[0016] As a result of intensive research conducted by the present inventors to solve the above-mentioned problems, they discovered that by using a compound having a structure in which a Group 16 element of the periodic table is bonded in a specific manner to a relatively large aromatic skeleton, a phosphorescent material can be obtained that not only exhibits room-temperature phosphorescence in the red or near-infrared region but also exhibits long-life and high brightness phosphorescence, thereby completing the present invention. The present invention was made based on the above-mentioned findings. That is, the gist of the present invention is as follows.

[0017] [1] A polycyclic aromatic skeleton or an element X selected from S, P, N, or Si ２ The cyclic skeleton is bonded to the polycyclic aromatic skeleton via a group 16 element of the periodic table, X １ is directly bonded to the compound (the element X １ may form a ring together with other elements, provided that in this case, the ring does not include the X １ and carbon C only bonded to each other.

[0018] [2] The polycyclic aromatic skeleton has the element X １ In the compound in which the element X is directly bonded, １ is further bonded to an aromatic skeleton other than the polycyclic aromatic skeleton.

[0019] [3] The polycyclic aromatic skeleton has the element X １ In the compound in which the element X is directly bonded, １ is directly bonded to a carbon atom on which the highest occupied molecular orbital (HOMO) and / or the lowest unoccupied molecular orbital (LUMO) of the polycyclic aromatic skeleton is located.

[0020] [4] The polycyclic aromatic skeleton has the element X １ is directly bonded to the polycyclic aromatic skeleton, the polycyclic aromatic skeleton consisting of a main polycyclic aromatic skeleton and a spacer aromatic skeleton that is single-bonded to the main polycyclic aromatic skeleton.

[0021] [5] The polycyclic aromatic skeleton has the element X １ In the compound in which the element X is directly bonded,１ is directly bonded to the spacer aromatic skeleton.

[0022] [6] The polycyclic aromatic skeleton has the element X １ In the compound in which the element X is directly bonded, １ and the interatomic distance between the carbon atom to which the spacer aromatic skeleton is bonded in the main polycyclic aromatic skeleton is 3.050 Å or more and 3.500 Å or less.

[0023] [7] The polycyclic aromatic skeleton has the element X １ In the compound in which the spacer aromatic skeleton and the element X are directly bonded, １ The number of each element X is 2 or more, １ is directly bonded to each spacer aromatic skeleton, and each element X １ and the interatomic distance between the carbon atom of the main polycyclic aromatic skeleton to which the spacer aromatic skeleton is bonded is 3.000 Å or more and 3.500 Å or less.

[0024] [8] The polycyclic aromatic skeleton has the element X １ is directly bonded to the compound, the energy level of the lowest triplet state of the spacer aromatic skeleton is higher than the energy level of the lowest triplet state of the main polycyclic aromatic skeleton.

[0025] [9] The polycyclic aromatic skeleton has the element X １ is directly bonded to the main polycyclic aromatic skeleton, a carbon atom in the main polycyclic aromatic skeleton that is single-bonded to the spacer aromatic skeleton is designated as point a, a carbon atom in the spacer aromatic skeleton that is single-bonded to the main polycyclic aromatic skeleton is designated as point b, and the element X １ When point a and point b are defined as point c, the angle θ between the line segment ab connecting point a and point b and the line segment ac connecting point a and point c is １A The luminous material according to any one of [4] to [8], wherein the angle is 60.0° or more and 90.0° or less.

[0026]

[10] The polycyclic aromatic skeleton has the element X１ is directly bonded to the spacer aromatic skeleton, a carbon atom in the main polycyclic aromatic skeleton that is single-bonded to the spacer aromatic skeleton is designated as point a, a carbon atom in the spacer aromatic skeleton that is single-bonded to the main polycyclic aromatic skeleton is designated as point b, and the element X directly bonded to the spacer aromatic skeleton is designated as point a. １ When point a is set as point c, the angle θ between the plane including points a, b, and c and the plane of the benzene ring that constitutes point a ２A The luminous material according to any one of [4] to [9], wherein the angle is 50.0° or more and 85.0° or less.

[0027]

[11] The polycyclic aromatic skeleton has the element X １ In the compound in which the element X is directly bonded, １ is further bonded to an aromatic skeleton other than the polycyclic aromatic skeleton, and the element X in the aromatic skeleton １ When the carbon atom to which is bonded is defined as point d, the angle θ formed by the line segment ca connecting point c and point a and the line segment cd connecting point c and point d is ３Ａ The phosphorescent material according to [9] or

[10] , wherein the angle is 85.0° or more and 165.0° or less.

[0028]

[12] The element X ２ The element X is bonded to a cyclic skeleton bonded to a polycyclic aromatic skeleton via １ In the compound in which the element X is directly bonded, １ is further bonded to an aromatic skeleton other than the cyclic skeleton.

[0029]

[13] The element X ２ The element X is bonded to a cyclic skeleton bonded to a polycyclic aromatic skeleton via １ In the compound in which the element X is directly bonded, １ and the element X ２ The luminous material according to any one of [1] to

[12] , wherein the interatomic distance between

[0030]

[14] The element X ２ The element X is bonded to a cyclic skeleton bonded to a polycyclic aromatic skeleton via １is directly bonded to the compound, the energy level of the lowest triplet state of the cyclic skeleton is higher than the energy level of the lowest triplet state of the polycyclic aromatic skeleton.

[0031]

[15] The element X ２ The element X is bonded to a cyclic skeleton bonded to a polycyclic aromatic skeleton via １ In the compound in which the element X is directly bonded, ２ is set as point e, and the element X in the cyclic skeleton ２ The carbon atom bonded to the element X is defined as point f. １ When point g is the angle θ between the line segment ef connecting points e and f and the line segment eg connecting points e and g, １Ｂ

[15] The luminous material according to any one of [1] to

[14] , wherein the angle is 55.0° or more and 65.0° or less.

[0032]

[16] The element X ２ The element X is bonded to a cyclic skeleton bonded to a polycyclic aromatic skeleton via １ In the compound in which the element X is directly bonded, １ is further bonded to an aromatic skeleton other than the cyclic skeleton, and the element X in the aromatic skeleton １ When the carbon atom to which is bonded is defined as point h, the angle θ formed by the line segment ge connecting point g and point e and the line segment gh connecting point g and point h is ３Ｂ The phosphorescent material according to

[15] , wherein the angle is 140.0° or more and 160.0° or less.

[0033]

[17] The phosphorescent material according to any one of [1] to

[16] , wherein the polycyclic aromatic skeleton is selected from the following:

[0034]

[18] The luminous material according to any one of [1] to

[17] , wherein the content of the compound is 0.001% by mass or more and 30% by mass or less.

[0035]

[19] A luminous material for a living organism, wherein the luminous material according to any one of [1]1 to

[18] is introduced into a living organism to identify the characteristics of the living organism.

[0036]

[20] A luminous particle, characterized in that the luminous material according to any one of [1] to

[18] or the luminous material for living organisms according to

[19] is granulated and the surface of the luminous particle is coated with a polymer.

[0037]

[21] A dispersion liquid obtained by dispersing the phosphorescent particles according to

[20] in a solvent.

[0038]

[22] A display medium, characterized by using a film made of the phosphorescent material according to any one of [1] to

[18] .

[0039] According to the present invention, it is possible to provide a phosphorescent material that exhibits room-temperature phosphorescence in the red or near-infrared region, and that exhibits long-life and high brightness phosphorescence. Furthermore, according to the present invention, it is possible to provide phosphorescent particles, dispersions, and display media using the above phosphorescent material.

[0040] FIG. 1 is an explanatory diagram illustrating the phosphorescence phenomenon caused by room temperature phosphorescence.

[0041] The luminous material, luminous particles, dispersion, and display medium of the present invention will be described below based on embodiments. However, such descriptions are for the purpose of illustrating the present invention and are not intended to limit the present invention in any way.

[0042] Each component disclosed in this specification, as well as the preferred embodiments, numerical ranges, and thresholds defining such numerical ranges shown for each component, can be independently combined with each other in any manner.

[0043] (Luminescent Material) A luminescent material according to one embodiment of the present invention (hereinafter, sometimes referred to as "luminescent material of this embodiment") has a polycyclic aromatic skeleton or an element X selected from S, P, N, or Si. ２ The cyclic skeleton is bonded to the polycyclic aromatic skeleton via a group 16 element of the periodic table, X １ is directly bonded to the compound (the element X １ may form a ring together with other elements, provided that in this case, the ring does not include the X １and carbon C are bonded to each other. In other words, the phosphorescent material of this embodiment is characterized in that it contains a polycyclic aromatic skeleton containing an element X of Group 16 of the periodic table. １ and a compound A to which the polycyclic aromatic skeleton and the cyclic skeleton are directly bonded, and an element X selected from S, P, N, or Si is bonded to the compound A. ２ and is bonded via a group 16 element X of the periodic table. １ is directly bonded to the cyclic skeleton (the element X １ may form a ring together with other elements, provided that in this case, the ring does not include the X １ and carbon C bonded thereto.

[0044] The term "luminous material" refers to a material that exhibits a luminous phenomenon, and is also referred to as a "delayed luminescence material" in the art. Specifically, in this specification, the term "luminous material" refers to a material that exhibits a luminous phenomenon, and exhibits a mean lifetime τ measured using a two-dimensional photodetector after irradiation with 360 nm excitation light and stopping the irradiation. Ｐ Therefore, for example, even if a compound corresponding to Compound A or Compound B is contained, it is possible to use a material that does not exhibit the phosphorescence phenomenon (a measured average lifetime τ Ｐ A material having a light-storage time of less than 100 ms does not fall under the category of the light-storage material of the present invention.

[0045] In this specification, the above-mentioned average life τ Ｐ If the life span is 100 ms or more, it can be considered as "long life."

[0046] In the following, the polycyclic aromatic skeleton is formed by adding an element X of Group 16 of the periodic table. １ is directly bonded to the compound (the element X １ may form a ring together with other elements, provided that in this case, the ring does not include the X １ and carbon C bonded thereto.) is sometimes simply referred to as "compound A." Hereinafter, ２ The cyclic skeleton is bonded to the polycyclic aromatic skeleton via a group 16 element of the periodic table, X １ is directly bonded to the compound (the element X １may form a ring together with other elements, provided that in this case, the ring does not include the X １ and carbon C bonded thereto.) may be simply referred to as "compound B." Hereinafter, compound A and compound B may be collectively referred to as "compounds of the present embodiment."

[0047] First, the light-storing phenomenon caused by room temperature phosphorescence will be described with reference to Fig. 1. In a material that exhibits the light-storing phenomenon caused by room temperature phosphorescence, the material (particularly, molecules) absorbs light as energy and enters the lowest singlet excited state (S １ ) is formed ((1) in FIG. 1), which then undergoes intersystem crossing to the triplet state, resulting in the lowest triplet excited state (T １ ) is formed ((2) in Figure 1). The remaining energy is then １ The deactivation is used for phosphorescence ((3) in Figure 1), which is a radiation process from T ((4) in Figure 1), deactivation due to intramolecular vibration ((4) in Figure 1), or deactivation due to energy transfer to the host material ((5) in Figure 1). １ Phosphorescence (FIG. 1 (3)), which is a radiation process from the molecule, is a slow photophysical process, and therefore the emitted light remains for as long as several to 10 seconds after the irradiation of the excitation light is stopped.

[0048] Here, an index of the brightness of the phosphorescent material is the room temperature phosphorescence quantum yield. ｐ (RT) (hereinafter simply referred to as Φ ｐ The room temperature phosphorescence quantum yield Φ ｐ is generally considered to satisfy the following relationship (i): In the above relationship (i), k ｐ is the phosphorescence rate constant, which is a factor related to the degree of (3) in Figure 1. ｎｒ is the lowest vibrationally excited triplet state (T １ ) to the ground state (S ０ ) and is a factor related to the degree of (4) in Figure 1. From the relationship (i) above, k ｐ The larger k ｎｒ The smaller the value, the higher the room temperature phosphorescence quantum yield Φ ｐ will be higher.

[0049] Furthermore, according to the literature, the lowest triplet excited state (T １ When the molecular structure of ｐ and k ｎｒ are considered to tend to satisfy the following relationships (ii) and (iii), respectively (see S. Hirata, J. Phys. Chem. Lett. 2018, 9, 4251, k ｐ and k ｎｒ (Estimated). In the above relationship (ii), (μ Ｓｎ－Ｓ０ ) is a higher singlet excited state (S ｎ ) (where n≧1) and the ground state (S ０ ) is the transition dipole moment between (SOC Ｓｎ－Ｔ１ ) is a higher singlet excited state (S ｎ ) (where n≧1) and the lowest triplet excited state (T １ ) is the spin-orbit interaction between the two. Ｔ１－Ｓ０ ) is the lowest triplet excited state (T １ ) and the ground state (S ０ In the relationships (ii) and (iii) above, λ is the peak wavelength of the phosphorescence spectrum.

[0050] According to the relationships (ii) and (iii) above, k ｐ is proportional to the -3rd power of the peak wavelength of the phosphorescence spectrum, and k ｎｒ is proportional to the square of the peak wavelength of the phosphorescence spectrum. In other words, when the peak wavelength of phosphorescence is in the red region or near-infrared region (for example, 600 nm or more), the peak wavelength is larger than that in the blue region to orange region, so k ｐ tends to be relatively small, and k ｎｒ As a result, the phosphorescence of conventional phosphorescent materials with peak wavelengths in the red or near-infrared region has a room temperature phosphorescence quantum yield Φ ｐ The inference was made that the value is unlikely to become high.

[0051] Therefore, the inventors have determined that the room temperature phosphorescence quantum yield Φ ｐ In order to increase the "(SOC Ｔ１－Ｓ０ )) in the above (ii) without much influence on "(μ Ｓｎ－Ｓ０ ) x (SOC Ｓｎ－Ｔ１ The inventors have made extensive efforts to design molecular structures that can increase the value of "(n≧1)" (where n≧1). As a result of optimizing the structure of the side chain of the skeleton corresponding to the chromophore, the inventors have found that compounds having a polycyclic aromatic skeleton and a Group 16 element in a predetermined manner (i.e., Compound A and Compound B) contribute to satisfying the above-mentioned requirements.

[0052] The reason why Compound A and Compound B contribute to satisfying the above requirements is not clear, but is presumed to be as follows: In Compound A, the Group 16 element X is contained in the polycyclic aromatic skeleton. １ are directly bonded, (SOC Ｔ１－Ｓ０ ) than the increase in (SOC Ｓｎ－Ｔ１ ) (where n≧1) increases more. In addition, in compound B, an element X selected from S, P, N, or Si ２ A cyclic skeleton bonded to a polycyclic aromatic skeleton via a group 16 element X １ are directly bonded, (SOC Ｔ１－Ｓ０ ) than the increase in (SOC Ｓｎ－Ｔ１ ) (where n≧1) has the characteristic that the degree of increase is larger. Furthermore, in the above-mentioned compounds A and B, Ｓｎ－Ｔ１ For n (where n ≥ 1) where the rate of increase of ) is large, (μ Ｓｎ－Ｓ０ ) also has the characteristic of maintaining a large value. Ｓｎ－Ｔ0 ) compared to the increase in (μ Ｓｎ－Ｓ０ ) x (SOC Ｓｎ－Ｔ１ ) (where n≧1) increases even more, resulting in a mean lifespan τ Ｐ High room temperature phosphorescence quantum yield Φ while maintaining a long lifetime of over 100 ms ｐTherefore, the luminous material of the present embodiment containing Compound A or Compound B not only exhibits room-temperature phosphorescence in the red or near-infrared region, but also provides phosphorescence with a long life and high brightness.

[0053] In this specification, the "red region" refers to a wavelength range of 600 to 770 nm, and the "near-infrared region" refers to a wavelength range of 0.7 to 2.5 μm.

[0054] The phosphorescent material of this embodiment has a peak wavelength λ of room temperature phosphorescence. ｐ is preferably in the red region or the near-infrared region. In particular, the peak wavelength λ of the room-temperature phosphorescence of the light-storing material of this embodiment is ｐ The peak wavelength λ can be 600 nm or more and 700 nm or less, 600 nm or more and 680 nm or less, 600 nm or more and 670 nm or less, or 600 nm or more and 650 nm or less. ｐ can be adjusted, for example, by appropriately selecting the polycyclic aromatic skeleton in the compounds used in this embodiment (i.e., Compound A and Compound B), or by imparting other conjugated substituents to the polycyclic aromatic skeleton.

[0055] The light-storing material of this embodiment may be one in which the compounds of this embodiment (i.e., compound A and compound B) alone exhibit the light-storing phenomenon, or one in which the compounds alone do not exhibit the light-storing phenomenon but do so only when the compounds are dispersed in another material (host material).

[0056] The phosphorescent material of this embodiment may contain, in addition to the compound of this embodiment, materials other than the compound (e.g., a host material, various other additives, etc.). In this case, the phosphorescent material of this embodiment preferably contains the compound of this embodiment in an amount of 0.001% by mass or more and 30% by mass or less. By containing the compound of this embodiment in an amount of 0.001% by mass or more relative to the total amount of the phosphorescent material, the desired room-temperature phosphorescence characteristics can be reliably exhibited, and by containing the compound in an amount of 30% by mass or less, deactivation of room-temperature phosphorescence due to aggregation of the compound of this embodiment can be suppressed. From the same viewpoint, the content of the compound of this embodiment relative to the total amount of the phosphorescent material is more preferably 0.01% by mass or more, even more preferably 0.1% by mass or more, more preferably 10% by mass or less, and even more preferably 3% by mass or less.

[0057] The light-storing material of this embodiment is preferably a solid light-storing material in which the compound of this embodiment is dispersed in another solid material (for example, a host material).

[0058] The luminous material of this embodiment can be used for various purposes, such as an indicator light for nighttime or dark places, a security medium for preventing counterfeiting, bioimaging, etc.

[0059] In particular, the luminous material of this embodiment can be used to identify the characteristics of a living organism by being introduced into the organism, as typified by bioimaging. That is, the luminous material of this embodiment can be suitably used as a luminous material for a living organism.

[0060] Next, each component that can be contained in the luminous material of this embodiment will be described.

[0061] <Compound A> The light-storing material of this embodiment is a compound of this embodiment, namely, a compound A having a polycyclic aromatic skeleton and a group 16 element X of the periodic table. １ is directly bonded to the compound A. The polycyclic aromatic skeleton in the compound A is substantially a portion corresponding to the chromophore. The compound A contained in the light-storing material of the present embodiment may be one type alone or a combination of two or more types.

[0062] In this specification, the term "polycyclic aromatic skeleton" (hereinafter, unless otherwise specified, includes not only the polycyclic aromatic skeleton in compound A but also the polycyclic aromatic skeleton in compound B) refers to a skeleton having two or more cyclic structures, at least a portion of which is aromatic. In particular, it is preferable that such a polycyclic aromatic skeleton is aromatic as a whole.

[0063] The polycyclic aromatic skeleton may include a fused ring (e.g., it may be composed of only a fused ring, or may include a fused ring to which a monocyclic ring or another fused ring is bonded), or it may include no fused ring (e.g., formed by bonding two or more monocyclic rings). Alternatively, the polycyclic aromatic skeleton may include a monocyclic benzene ring (a non-fused benzene ring).

[0064] When the polycyclic aromatic skeleton has a fused ring, the number of carbon atoms in the fused ring is preferably 10 or more and 40 or less. Within this range, the peak wavelength of phosphorescence tends to be in the red region or near-infrared region, and better phosphorescent properties can be exhibited. From the same viewpoint, the number of carbon atoms in the fused ring is more preferably 14 or more and more preferably 30 or less.

[0065] Furthermore, the cyclic structure in the polycyclic aromatic skeleton may be formed by bonding only carbon atoms, or may be formed by bonding carbon atoms and elements other than carbon atoms (i.e., a heterocycle).

[0066] The polycyclic aromatic skeleton is preferably a conjugated skeleton.

[0067] Specific examples of polycyclic aromatic skeletons include the following (classified as the first group):

[0068] Specific examples of the polycyclic aromatic skeleton include the following (classified as the second group):

[0069] The polycyclic aromatic skeleton can be selected from the skeletons classified into the first and second groups described above.

[0070] Among the above, the following polycyclic aromatic skeletons are more preferred. These polycyclic aromatic skeletons have a twist in the fused ring structure, and this twist can further improve the desired performance.

[0071] In the polycyclic aromatic skeleton, some or all of the hydrogen atoms may be substituted with deuterium (D). ｎｒ (Deactivation rate constant) is not only related to the above (iii), but also to T １ and S ０ When a part or all of the periphery of the polycyclic aromatic skeleton is replaced with deuterium, T １ and S ０ The Franck-Condon factor between k and k becomes smaller, so k ｎｒ Therefore, the room temperature phosphorescence quantum yield Φ ｐ (brightness) can be further increased.

[0072] In addition, in the compound A, the polycyclic aromatic skeleton contains an element X of Group 16 of the periodic table. １ are directly bonded to the element X in group 16 of the periodic table. １ Examples of the group 16 element X that is directly bonded to the polycyclic aromatic skeleton include oxygen (O), sulfur (S), selenium (Se), tellurium (Te), polonium (Po), and livermorium (Lv). １ is preferably selected from sulfur (S), selenium (Se), tellurium (Te), polonium (Po), and livermorium (Lv), and more preferably selected from sulfur (S) and selenium (Se), from the viewpoint of exhibiting better phosphorescent properties.

[0073] Compound A (i.e., a polycyclic aromatic skeleton containing element X) １ In the compound in which element X is directly bonded to the polycyclic aromatic skeleton, １The number of elements X directly bonded to the polycyclic aromatic skeleton is not particularly limited, and may be 1, 2, 3, 4, or 5 or more. １ When the number of substitutions is 2 or more, １ may be one type alone or a combination of two or more types.

[0074] Compound A (i.e., a polycyclic aromatic skeleton containing element X) １ In the compound in which element X is directly bonded, １ is preferably directly bonded to a carbon atom that is double-bonded to another carbon atom (for example, a carbon atom that constitutes an aromatic ring).

[0075] Compound A (i.e., a polycyclic aromatic skeleton containing element X) １ In the compound in which element X is directly bonded to the polycyclic aromatic skeleton, １ is preferably further bonded to an aromatic skeleton other than the polycyclic aromatic skeleton. In this case, the desired performance can be further improved. １ Examples of the skeleton on the terminal side of the alkylene group include a benzene skeleton, a naphthalene skeleton, a fluorene skeleton, a phenanthrene skeleton, and a chrysene skeleton.

[0076] In addition, compound A (i.e., a polycyclic aromatic skeleton containing element X) １ is directly bonded to the element X １ may form a ring together with other elements. In this case, the ring may be formed by the above-mentioned X １ and carbon C are bonded together. That is, element X １ However, compounds that form a ring with carbon C and elements other than carbon C (heteroatoms) do not fall under Compound A.

[0077] Compound A (i.e., a polycyclic aromatic skeleton containing element X) １ In the compound in which the polycyclic aromatic skeleton and the group 16 element X are directly bonded, １ The bond is preferably a covalent bond, which can provide a longer phosphorescent lifetime (phosphorescent lifetime) than a complex in which a metal is coordinately bonded to a ligand (used in organic electroluminescence, etc.).

[0078] Compound A (i.e., a polycyclic aromatic skeleton containing element X) １ is directly bonded to the element X １ is preferably directly bonded to a carbon atom on which the highest occupied molecular orbital (HOMO) and / or the lowest unoccupied molecular orbital (LUMO) of the polycyclic aromatic skeleton is located. In this case, the brightness can be further increased. １ The carbon atom to which is directly bonded may have a HOMO, a LUMO, or both a HOMO and a LUMO.

[0079] Whether or not a carbon atom has a HOMO and / or LUMO can be determined by the following procedure. That is, from a certain conformation, the lowest excited triplet (T １ When the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) are determined in this conformation, the optimization of the element X １ It is then confirmed whether a HOMO and / or LUMO is displayed on the carbon atom to which the carbon atom is directly bonded under the condition of an isovalue of 0.03. If a HOMO and / or LUMO is displayed, the carbon atom can be identified as having a HOMO and / or LUMO.

[0080] Compound A (i.e., a polycyclic aromatic skeleton containing element X) １ In the compound A (i.e., a compound having an element X directly bonded to the polycyclic aromatic skeleton), the polycyclic aromatic skeleton preferably comprises a main polycyclic aromatic skeleton and a spacer aromatic skeleton that is single-bonded to the main polycyclic aromatic skeleton. １ is directly bonded to the main polycyclic aromatic skeleton), one in which the polycyclic aromatic skeleton consists of a main polycyclic aromatic skeleton and a spacer aromatic skeleton that is single-bonded to the main polycyclic aromatic skeleton is sometimes referred to as "compound A1".

[0081] The main polycyclic aromatic skeleton in Compound A1 is preferably composed of only fused rings. Furthermore, the cyclic structure in the main polycyclic aromatic skeleton is preferably not a heterocycle. Examples of the main polycyclic aromatic skeleton include those listed above as the first group of polycyclic aromatic skeletons.

[0082] Examples of the spacer aromatic skeleton in Compound A1 include a benzene skeleton, a naphthalene skeleton, and a fluorene skeleton.

[0083] In the compound A1, the element X １ is preferably directly bonded to the spacer aromatic skeleton. １ and the carbon atom to which the spacer aromatic skeleton is bonded in the main polycyclic aromatic skeleton is preferably 3.050 Å or more and 3.500 Å or less. １ Through-space electrons are favorably generated between the main polycyclic aromatic skeleton and the cyclic aromatic ring, and due to through-space interactions, the room temperature phosphorescence quantum yield Φ ｐ From the same viewpoint, it is more preferable that the interatomic distance is 3.170 Å or more.

[0084] The interatomic distance can be measured by the following procedure. That is, from one conformation, the lowest excited triplet (T １ ) state optimization, and the interatomic distance can be measured from the coordinates of two atoms obtained in the conformation in such an optimized structure.

[0085] In addition, in the compound A1, the spacer aromatic skeleton and the element X １ The number of elements (the number of through spaces) is 2 or more, and each element X １ is directly bonded to each spacer aromatic skeleton, and each element X １and the carbon atom to which the spacer aromatic skeleton is bonded in the main polycyclic aromatic skeleton are preferably 3.000 Å or more and 3.500 Å or less. In this case, two or more of the above-mentioned through-space electrons are preferably generated, and the room temperature phosphorescence quantum yield Φ ｐ From the same viewpoint, the spacer aromatic skeleton and the element X １ The number (the number of through spaces) is more preferably 3 or more, and even more preferably 4 or more.

[0086] In Compound A1, the energy level of the lowest triplet state of the spacer aromatic skeleton is preferably higher than the energy level of the lowest triplet state of the main polycyclic aromatic skeleton, in which case the lowest triplet excited state formed in the main polycyclic aromatic skeleton after photoexcitation is unlikely to transfer to the spacer aromatic skeleton, thereby effectively suppressing a decrease in phosphorescence yield (brightness).

[0087] The energy levels of the lowest triplet state, for example, the energy level of the lowest triplet state of the spacer aromatic skeleton and the energy level of the lowest triplet state of the main polycyclic aromatic skeleton, can be measured by the following procedure. That is, a molecule consisting of only the spacer aromatic skeleton and a molecule consisting of the main polycyclic aromatic skeleton are prepared, and the phosphorescence spectrum of each molecule upon irradiation with excitation light is measured at room temperature or liquid nitrogen temperature, thereby measuring the above-mentioned energy levels. Furthermore, if phosphorescence from a molecule consisting of only the spacer aromatic skeleton is not observed even at liquid nitrogen temperature, the lowest triplet energy of the molecule consisting of only the spacer aromatic skeleton and the molecule consisting of the main polycyclic aromatic skeleton can also be estimated by quantum chemical calculation. For example, the lowest excited triplet energy (T １ ) state optimization. １For the state-optimized structure, it is possible to calculate the energy level of the lowest triplet state based on the time-resolved DFT method using B3LYP as the functional and 6-31G(d) or 6-311G(d,p) as the basis functions.

[0088] In Compound A1, a carbon atom in the main polycyclic aromatic skeleton that is single-bonded to the spacer aromatic skeleton is designated as point a, a carbon atom in the spacer aromatic skeleton that is single-bonded to the main polycyclic aromatic skeleton is designated as point b, and the element X １ When point a is point c, the angle θ between the line segment ab connecting point a and point b and the line segment ac connecting point a and point c is １A It is preferable that the angle θ is equal to or greater than 60.0° and equal to or less than 90.0°. １A When is in the above range, (SOC Ｔ１－Ｓ０ ) than the increase in (SOC Ｓｎ－Ｔ１ ) (where n≧1) tends to increase more rapidly, and furthermore, (SOC Ｓｎ－Ｔ１ ) (where n ≥ 1) for a large increase in n, (μ Ｓｎ－Ｓ０ ) (where n≧1) also tends to maintain a large value. Ｔ１－Ｓ０ ) compared to the increase in (μ Ｓｎ－Ｓ０ ) x (SOC Ｓｎ－Ｔ１ ) (where n≧1) increases further. As a result, from the above formulas (i) and (ii), the average life τ Ｐ High room temperature phosphorescence quantum yield Φ while maintaining a long lifetime of over 100 ms ｐ On the other hand, the angle θ １A If it is not within the above range, the above-mentioned effect is small.

[0089] The angle can be measured by the following procedure: from one conformation, the T is calculated based on the density functional (DFT) method using Gaussian09 software, with B3LYP as the functional and 6-31G(d) or 6-311G(d,p) as the basis function. １ The optimized state is calculated, and angles can be determined from the coordinates of the corresponding atoms obtained in the conformation in such an optimized structure.

[0090] In addition, in the compound A1, the angle θ between the plane including the above-mentioned points a, b, and c and the plane of the benzene ring constituting the above-mentioned point a is ２A is preferably 50.0° or more and 85.0° or less. ２A When is in the above range, (SOC Ｔ１－Ｓ０ ) than the increase in (SOC Ｓｎ－Ｔ１ ) (where n≧1) tends to increase more rapidly, and furthermore, (SOC Ｓｎ－Ｔ１ ) (where n ≥ 1) for a large increase in n, (μ Ｓｎ－Ｓ０ ) (where n≧1) also tends to maintain a large value. Ｔ１－Ｓ０ ) compared to the increase in (μ Ｓｎ－Ｓ０ ) x (SOC Ｓｎ－Ｔ１ ) (where n≧1) increases further. As a result, from the above formulas (i) and (ii), the average life τ Ｐ High room temperature phosphorescence quantum yield Φ while maintaining a long lifetime of over 100 ms ｐ On the other hand, the angle θ ２A If it is not within the above range, the above-mentioned effect is small.

[0091] In addition, in the compound A1, the element X １ is further bonded to an aromatic skeleton other than a polycyclic aromatic skeleton, points a and c are defined in the same manner as above, and the element X １ When the carbon atom to which is bonded is defined as point d, the angle θ formed by the line segment ca connecting point c and point a and the line segment cd connecting point c and point d is ３A It is preferable that the angle θ is equal to or greater than 85.0° and equal to or less than 165.0°. ３A When is in the above range, (SOC Ｔ１－Ｓ０ ) than the increase in (SOC Ｓｎ－Ｔ１ ) (where n≧1) tends to increase more rapidly, and furthermore, (SOC Ｓｎ－Ｔ１ ) (where n ≥ 1) for a large increase in n, (μ Ｓｎ－Ｓ０ ) (where n≧1) also tends to maintain a large value. Ｔ１－Ｓ０ ) compared to the increase in (μＳｎ－Ｓ０ ) x (SOC Ｓｎ－Ｔ１ ) (where n≧1) increases further. As a result, from the above formulas (i) and (ii), the average life τ Ｐ High room temperature phosphorescence quantum yield Φ while maintaining a long lifetime of over 100 ms ｐ On the other hand, the angle θ ３A If it is not within the above range, the above-mentioned effect is small.

[0092] The synthesis method of Compound A is not particularly limited. Compound A can be synthesized by appropriately combining known synthesis methods and / or conditions. For example, Compound A can be synthesized by a reaction in which diphenyl disulfide is reacted with a bromo-substituted polycyclic aromatic skeleton in the presence of a palladium catalyst; a reaction in which a bromo-substituted polycyclic aromatic skeleton is bonded to an iodo-substituted aromatic skeleton (iodobenzene, iodonaphthalene, iodofluorene) via potassium thioacetate; or the like.

[0093] <Compound B> The light-storing material of this embodiment includes, as the compound of this embodiment, compound B, that is, an element X selected from S, P, N, or Si. ２ The cyclic skeleton is bonded to the polycyclic aromatic skeleton via a group 16 element of the periodic table, X １ In other words, the compound B can include a compound in which a polycyclic aromatic skeleton and a cyclic skeleton are bonded to an element X selected from S (sulfur), P (phosphorus), N (nitrogen), or Si (silicon). ２ and is bonded via a group 16 element X of the periodic table. １ is a compound in which the polycyclic aromatic skeleton is directly bonded to the cyclic skeleton. The polycyclic aromatic skeleton in compound B is substantially a part corresponding to the chromophore. Compound B contained in the light-storing material of this embodiment may be one type alone or a combination of two or more types.

[0094] In addition, a compound that satisfies the requirements of both Compound A and Compound B (for example, Compound B containing element X ２ is S. In the case where both Compound A and Compound B are mentioned, such a compound can be classified as Compound B by definition.

[0095] Compound B (i.e., element X ２ A ring skeleton bonded to a polycyclic aromatic skeleton via an element X １ The polycyclic aromatic skeleton in Compound B (a compound to which is directly bonded) is the same as that described above for Compound A. Therefore, the description of Compound A will be used to describe the polycyclic aromatic skeleton in Compound B.

[0096] Compound B (i.e., element X ２ A ring skeleton bonded to a polycyclic aromatic skeleton via an element X １ In the compound in which the polycyclic aromatic skeleton and the cyclic skeleton are directly bonded to each other, an element X selected from S, P, N, or Si is ２ In other words, in compound B, a polycyclic aromatic skeleton and an element X selected from S, P, N, or Si are bonded via ２ and the cyclic skeleton are bonded in this order. ２ The bond with element X is typically a single bond. ２ The bond between and the cyclic skeleton is typically a single bond.

[0097] Compound B (i.e., element X ２ A ring skeleton bonded to a polycyclic aromatic skeleton via an element X １ is directly bonded to the element X ２ When has three or more bonds, it may be bonded to any element or group other than the polycyclic aromatic skeleton and the cyclic skeleton.

[0098] Compound B (i.e., element X ２ A ring skeleton bonded to a polycyclic aromatic skeleton via an element X １ is directly bonded to) the cyclic skeleton has one or more cyclic structures, and may be an alicyclic skeleton or a skeleton having aromaticity. Examples of such cyclic skeletons include a cyclohexane skeleton, a benzene skeleton, a naphthalene skeleton, and a fluorene skeleton. Among these, a benzene skeleton is preferred as the cyclic skeleton in compound B. Such a cyclic skeleton may or may not have any substituent.

[0099] In addition, in the compound B, the cyclic skeleton contains an element X of Group 16 of the periodic table. １ are directly bonded to the element X in group 16 of the periodic table. １ Examples of the group 16 element X that is directly bonded to the polycyclic aromatic skeleton include oxygen (O), sulfur (S), selenium (Se), tellurium (Te), polonium (Po), and livermorium (Lv). １ is preferably selected from sulfur (S), selenium (Se), tellurium (Te), polonium (Po), and livermorium (Lv), and more preferably selected from sulfur (S) and selenium (Se), from the viewpoint of exhibiting better phosphorescent properties.

[0100] Compound B (i.e., element X ２ A ring skeleton bonded to a polycyclic aromatic skeleton via an element X １ is directly bonded to the cyclic skeleton), １ is preferably further bonded to an aromatic skeleton other than the cyclic skeleton. In this case, the desired performance can be further improved. １ Examples of the aromatic skeleton (the skeleton at the terminal side of the aromatic group) include a benzene skeleton, a naphthalene skeleton, a fluorene skeleton, a phenanthrene skeleton, a chrysene skeleton, etc. The aromatic skeleton is typically different from the polycyclic aromatic skeleton described above.

[0101] In addition, compound B (i.e., element X ２ A ring skeleton bonded to a polycyclic aromatic skeleton via an element X １ is directly bonded to the element X １ may form a ring together with other elements. In this case, the ring may be formed by the above-mentioned X １ and carbon C are bonded together. That is, element X １ However, compounds that form a ring with carbon C and elements other than carbon C (heteroatoms) do not fall under compound B.

[0102] Compound B (i.e., element X ２ A ring skeleton bonded to a polycyclic aromatic skeleton via an element X １In the compound in which the element X is directly bonded, １ and the element X ２ In this case, the interatomic distance between the element X and the element X is preferably 3.200 Å or more and 3.350 Å or less. １ and element X ２ Through-space electrons are preferably generated between the two, and due to through-space interactions, the room temperature phosphorescence quantum yield Φ ｐ (brightness) can be further increased.

[0103] In Compound B, the energy level of the lowest triplet state of the cyclic skeleton is preferably higher than the energy level of the lowest triplet state of the polycyclic aromatic skeleton. In this case, the lowest triplet excited state formed in the polycyclic aromatic skeleton after photoexcitation is unlikely to transfer to the cyclic skeleton, thereby effectively suppressing a decrease in phosphorescence yield (brightness).

[0104] In compound B, element X ２ is set as point e, and the element X in the cyclic skeleton ２ The carbon atom bonded to the element X is defined as point f. １ When point g is the angle θ between the line segment ef connecting points e and f and the line segment eg connecting points e and g, １Ｂ It is preferable that the angle θ is 55.0° or more and 65.0° or less. １Ｂ When is in the above range, (SOC Ｔ１－Ｓ０ ) than the increase in (SOC Ｓｎ－Ｔ１ ) (where n≧1) tends to increase more rapidly, and furthermore, (SOC Ｓｎ－Ｔ１ ) (where n ≥ 1) for a large increase in n, (μ Ｓｎ－Ｓ０ ) (where n≧1) also tends to maintain a large value. Ｔ１－Ｓ０ ) compared to the increase in (μ Ｓｎ－Ｓ０ ) x (SOC Ｓｎ－Ｔ１ ) (where n≧1) increases further. As a result, from the above formulas (i) and (ii), the average life τ Ｐ High room temperature phosphorescence quantum yield Φ while maintaining a long lifetime of over 100 ms ｐ On the other hand, the angle θ １ＢIf it is not within the above range, the above-mentioned effect is small.

[0105] In addition, in compound B, element X １ is further bonded to an aromatic skeleton other than the cyclic skeleton, points e and g are defined in the same manner as above, and the element X １ When the carbon atom to which is bonded is defined as point h, the angle θ formed by the line segment ge connecting point g and point e and the line segment gh connecting point g and point h is ３Ｂ It is preferable that the angle θ is equal to or greater than 140.0° and equal to or less than 160.0°. ３B When is in the above range, (SOC Ｔ１－Ｓ０ ) than the increase in (SOC Ｓｎ－Ｔ１ ) (where n≧1) tends to increase more rapidly, and furthermore, (SOC Ｓｎ－Ｔ１ ) (where n ≥ 1) for a large increase in n, (μ Ｓｎ－Ｓ０ ) (where n≧1) also tends to maintain a large value. Ｔ１－Ｓ０ ) compared to the increase in (μ Ｓｎ－Ｓ０ ) x (SOC Ｓｎ－Ｔ１ ) (where n≧1) increases further. As a result, from the above formulas (i) and (ii), the average life τ Ｐ High room temperature phosphorescence quantum yield Φ while maintaining a long lifetime of over 100 ms ｐ On the other hand, the angle θ ３B If it is not within the above range, the above-mentioned effect is small.

[0106] The synthesis method of compound B is not particularly limited. Compound B can be synthesized by appropriately combining known synthesis methods and / or conditions. For example, compound B can be synthesized by reacting a bromo-substituted polycyclic aromatic skeleton with a cyclic skeleton in which the aromatic skeleton is bromo-substituted and iodo-substituted in the presence of potassium S-thioacetate in the presence of a palladium catalyst to prepare a compound in which the aromatic skeleton and the bromo-substituted cyclic skeleton are bonded via sulfur, and then reacting the compound with diphenyl diselenide.

[0107] <Materials Other Than the Compounds of the Present Embodiment> As described above, the light-storing material of the present embodiment may contain materials other than the compounds of the present embodiment (i.e., Compound A and Compound B). Examples of materials other than the compounds of the present embodiment include a host material and various other additives.

[0108] Examples of the host material include crystalline benzophenone, amorphous β-estradiol, amorphous 2,8-bis(diphenyl-phosphoryl)-dibenzo[b,d]thiophene, etc. The host material may be used alone or in combination of two or more.

[0109] (Luminescent particles) The luminescent particles according to one embodiment of the present invention (hereinafter, sometimes referred to as "luminescent particles of this embodiment") are characterized in that the above-mentioned luminescent material is granulated and the surface of the granulated material is coated with a polymer.

[0110] In the phosphorescent particles of this embodiment, the polymer that coats the surface of the particulate phosphorescent material is not particularly limited, and examples thereof include poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) diacrylate.

[0111] The luminescent particles of this embodiment preferably have an average particle diameter of 10 μm or less. In this case, for example, when the luminescent particles are mixed with a polymer binder or the like to prepare an ink or the like and printing is performed using this ink, the resulting printed matter will have excellent visual visibility. Furthermore, the lower limit of the average particle diameter of the luminescent particles is not particularly limited, but from a practical standpoint, it can be, for example, 0.01 μm or more.

[0112] The phosphorescent particles of this embodiment may be distributed on the market as they are, or may be dispersed in a liquid such as an aqueous liquid or an oily liquid and distributed on the market as a dispersion.

[0113] (Dispersion) A dispersion according to one embodiment of the present invention (hereinafter sometimes referred to as "the dispersion of this embodiment") is characterized in that it is obtained by dispersing the above-mentioned phosphorescent particles in a solvent.

[0114] By decorating a substrate with the dispersion liquid of this embodiment, a phosphorescent image can be formed. In particular, the dispersion liquid of this embodiment can be preferably used for bioimaging applications.

[0115] The solvent is not particularly limited, and examples thereof include water and organic solvents. The organic solvent is also not particularly limited, and known organic solvents can be appropriately selected and used.

[0116] (Display Medium) A display medium according to one embodiment of the present invention (hereinafter, sometimes referred to as "the display medium of this embodiment") is characterized in that it uses a film made of a phosphorescent material.

[0117] The display medium of this embodiment can be preferably used as a counterfeit prevention display medium that is excited by an LED, for example.

[0118] The present invention will be described in more detail below with reference to examples. However, these examples are intended to illustrate the present invention and are not intended to limit the present invention in any way.

[0119] (Synthesis of Compound A-1) Compound A-1 represented by the following formula was synthesized by the following method.

[0120] Dibenzo[g,p]chrysene (199.3 mg) was dissolved in chlorobenzene (11.78 mL) to obtain a solution. Separately, a mixture of chlorobenzene (5.0 mL) and bromine (0.10 mL) was prepared, and 1.56 mL of this mixture was added dropwise to the above solution. The reaction was carried out under a nitrogen atmosphere at 110°C for 1.8 days. The residual bromine was deactivated with a saturated aqueous sodium thiosulfate solution to terminate the reaction. The mixture was then separated using pure water and chloroform as solvents, and the organic layer was dehydrated with anhydrous sodium sulfate, and the solvent was removed using an evaporator. The product was then purified by silica gel chromatography (developing solvent: dichloromethane:hexane=1:9) to obtain a white compound (2-bromodibenzo[g,p]chrysene (170.20 mg) as the main component. The molecular weight of the obtained compound was measured using a mass spectrometer (TOF-MS) equipped with matrix-assisted laser desorption / ionization (MALDI), and was found to be 406.03521.

[0121] Next, 2-bromodibenzo[g,p]chrysene (150 mg), diphenyl disulfide (61.3 mg), [1,1'-bis(diphenylphosphino)ferrocene]palladium(II) (16.8 mg), and zinc (36.5 mg) were dissolved in tetrahydrofuran (4.5 mL) and reacted for 1 day under a nitrogen atmosphere at 70°C. The mixture was then separated into pure water and dichloromethane as solvents, the organic layer was dehydrated with anhydrous sodium sulfate, and the solvent was removed using an evaporator. The resulting mixture was purified by silica gel chromatography (developing solvent: dichloromethane:hexane = 1:9) to obtain whitish-yellow compound A-1 (99.28 mg).

[0122] (Synthesis of Compound A-1′) Compound A-1′ (represented by the following formula) was synthesized by substituting the hydrogen atoms of the polycyclic aromatic skeleton dibenzo[g,p]chrysene in Compound A-1 with deuterium (D) by the following method.

[0123] Dibenzo[g,p]chrysene (123.1 mg), palladium-activated carbon (Pd: 10% by mass) (124.8 mg), and heavy water (99.8% D) (25 mL) were reacted in an autoclave reaction vessel at 250°C for 12 hours. The mixture was then separated using pure water and chloroform as solvents, and the organic layer was dehydrated with anhydrous sodium sulfate. The residual carbon was removed by suction filtration, and the solvent was removed using a rotary evaporator. The product was then purified by silica gel chromatography (developing solvent: dichloromethane:hexane = 1:4) to obtain white dibenzo[g,p]chrysene-d １６ (92.80 mg) was obtained. The deuteration rate of the obtained compound was １ The purity was 90% as determined by 1 H NMR.

[0124] Then, dibenzo[g,p]chrysene-d １６ (87.9 mg) was dissolved in chlorobenzene (5.0 mL) to obtain a solution. Separately, a mixture of chlorobenzene (5.0 mL) and bromine (0.10 mL) was prepared, and 0.68 mL of this mixture was added dropwise to the above solution, followed by a reaction for 1.8 days at 110°C under a nitrogen atmosphere. The residual bromine was deactivated with a saturated aqueous sodium thiosulfate solution to terminate the reaction. Thereafter, the mixture was separated using pure water and chloroform as solvents, the organic layer was dehydrated with anhydrous sodium sulfate, and the solvent was removed using an evaporator. Next, the product was purified by silica gel chromatography (developing solvent: dichloromethane:hexane = 1:9) to obtain a white compound (2-bromodibenzo[g,p]chrysene-1,3,4,5,6,7,8,9,10,11,12,13,14,15,16-d １５ ) (17.31 mg) was obtained.

[0125] Then, 2-bromodibenzo[g,p]chrysene-1,3,4,5,6,7,8,9,10,11,12,13,14,15,16-d １５(60.62 mg), diphenyl disulfide (20.48 mg), [1,1'-bis(diphenylphosphino)ferrocene]palladium(II) (6.04 mg), and zinc (14.00 mg) were dissolved in tetrahydrofuran (1.4 mL) and reacted for 1 day under a nitrogen atmosphere at 70°C. The mixture was then separated into pure water and dichloromethane as solvents, the organic layer was dehydrated with anhydrous sodium sulfate, and the solvent was removed using an evaporator. The residue was purified by silica gel chromatography (developing solvent: dichloromethane:hexane = 1:9), yielding whitish yellow compound A-1' (43.20 mg).

[0126] (Synthesis of Compound A-2) Compound A-2 represented by the following formula was synthesized by the following method.

[0127] Dibenzo[g,p]chrysene (120 mg), palladium-activated carbon (Pd: 10% by mass) (125 mg), and heavy water (99.8% D) (25 mL) were reacted in an autoclave reaction vessel at 250°C for 12 hours. The mixture was then separated using pure water and dichloromethane as solvents, and the organic layer was dehydrated with anhydrous sodium sulfate. Residual carbon was removed by suction filtration, and the solvent was then removed using a rotary evaporator. A pale yellow powder was thus obtained.

[0128] Next, the obtained pale yellow powder, palladium-activated carbon (Pd: 10% by mass) (125 mg), and heavy water (99.8% D) (25 mL) were reacted in an autoclave reaction vessel at 250°C for 12 hours. After that, the mixture was separated using pure water and dichloromethane as solvents, and the organic layer was dehydrated with anhydrous sodium sulfate. The residual carbon was removed by suction filtration, and the solvent was removed using a rotary evaporator. In this way, a pale yellow powder was obtained.

[0129] Next, the obtained pale yellow powder, palladium-activated carbon (Pd: 10% by mass) (125 mg), and heavy water (99.8% D) (25 mL) were reacted in an autoclave reaction vessel at 250°C for 12 hours. The mixture was then separated using pure water and dichloromethane as solvents, and the organic layer was dehydrated with anhydrous sodium sulfate. The residual carbon was removed by suction filtration, and the solvent was removed using a rotary evaporator. In this way, a pale yellow powder was obtained. This was then purified by silica gel chromatography (developing solvent: dichloromethane:hexane = 1:4) to obtain white dibenzo[g,p]chrysene-d １６ (80 mg) was obtained. The deuteration rate of the obtained compound was １ The purity was determined by 1 H NMR to be 79%.

[0130] Then, dibenzo[g,p]chrysene-d １６ (80 mg) was dissolved in dehydrated chlorobenzene (4 mL) to obtain a solution. Separately, a mixture of chlorobenzene (5.0 mL) and bromine (0.10 mL) was prepared, and 1.45 mL of this mixture was added dropwise to the above solution, followed by a reaction under a nitrogen atmosphere at 110°C for 24 hours. Residual bromine was deactivated with saturated aqueous sodium thiosulfate to terminate the reaction. The mixture was then separated using pure water and chloroform as solvents, the organic layer was dehydrated with anhydrous sodium sulfate, and the solvent was removed using an evaporator. The product was then purified by silica gel chromatography (developing solvent: dichloromethane:hexane = 1:9) to obtain a white powder (96 mg) as the main component.

[0131] Next, the obtained powder (96 mg) and NaSPh (251 mg) were dissolved in dehydrated dimethylformamide (3.5 mL) and reacted for 24 hours under a nitrogen atmosphere at 150° C. Dimethylformamide was removed from the reaction solution as much as possible using an evaporator, and the resulting solution was purified by silica gel chromatography (developing solvent: dichloromethane:hexane=1:9) to obtain compound A-2 (83 mg).

[0132] (Synthesis of Compound A-3) Compound A-3 represented by the following formula was synthesized by the following method.

[0133] Dibenzo[g,p]chrysene-d with a deuteration rate of 79% １６ (65 mg) was dissolved in dehydrated chlorobenzene (4 mL) to obtain a solution. Separately, a mixture of chlorobenzene (5.0 mL) and bromine (0.10 mL) was prepared, and 2.16 mL of this mixture was added dropwise to the above solution, followed by a reaction under a nitrogen atmosphere at 110°C for 24 hours. Residual bromine was deactivated with a saturated aqueous sodium thiosulfate solution to terminate the reaction. The mixture was then separated using pure water and chloroform as solvents, the organic layer was dehydrated with anhydrous sodium sulfate, and the solvent was removed using an evaporator. The product was then purified by silica gel chromatography (developing solvent: dichloromethane:hexane = 1:9) to obtain a white powder (106 mg) as the main component.

[0134] Next, the obtained powder (106 mg) and NaSPh (437 mg) were dissolved in dehydrated dimethylformamide (3.1 mL) and reacted for 24 hours under a nitrogen atmosphere at 150° C. Dimethylformamide was removed from the reaction solution as much as possible using an evaporator, and the resulting solution was purified by silica gel chromatography (developing solvent: dichloromethane:hexane=1:9) to obtain compound A-3 (63 mg).

[0135] (Synthesis of Compound A-4) Compound A-4 represented by the following formula was synthesized by the following method.

[0136] Dibenzo[g,p]chrysene-d with a deuteration rate of 79% １６ (103 mg) was dissolved in dehydrated chlorobenzene (4 mL) to obtain a solution. Separately, a mixture of chlorobenzene (5.0 mL) and bromine (0.10 mL) was prepared, and 3.5 mL of this mixture was added dropwise to the above solution, followed by a reaction under a nitrogen atmosphere at 110°C for 24 hours. Residual bromine was deactivated with saturated aqueous sodium thiosulfate to terminate the reaction. The mixture was then separated using pure water and chloroform as solvents, the organic layer was dehydrated with anhydrous sodium sulfate, and the solvent was removed using an evaporator. The product was then purified by silica gel chromatography (developing solvent: dichloromethane:hexane = 1:9) to obtain a white powder (177 mg) as the main component.

[0137] Next, the obtained powder (177 mg) and NaSPh (714 mg) were dissolved in dehydrated dimethylformamide (5.1 mL) and reacted for 24 hours under a nitrogen atmosphere at 150° C. Dimethylformamide was removed from the reaction solution as much as possible using an evaporator, and the resulting solution was purified by silica gel chromatography (developing solvent: dichloromethane:hexane=1:9) to obtain compound A-4 (158 mg).

[0138] (Synthesis of Compound A-5) Compound A-5 represented by the following formula was synthesized by the following method.

[0139] 2-Bromodibenzo[g,p]chrysene (150 mg, 0.368 mmol), 1,2-diphenyldiselane (80.5 mg), [1,1'-Bis(diphenylphosphino)ferrocene]dichloropalladium(II) (13.5 mg), and zinc (33.7 mg) were added to a glass reaction vessel, and then dehydrated tetrahydrofuran (4.0 ml) was added under a nitrogen atmosphere to obtain a reaction solution. The reaction solution was heated at 68°C for 24 hours with stirring. After cooling to room temperature, chloroform was added. The reaction solution was washed with pure water, and the organic layer was dehydrated with sodium sulfate and then concentrated using a rotary evaporator. The residue was purified by silica gel column chromatography (dichloromethane:hexane=1:9) to obtain Compound A-5 (54.9 mg) as a pale yellow solid.

[0140] (Synthesis of Compound A-6) Compound A6 represented by the following formula was synthesized by the following method.

[0141] Pyrene-d １０(64.5 mg) and N-bromosuccinimide (55.7 mg) were dissolved in N,N-dimethylformamide (1.82 mL) and reacted for 40 hours with stirring at room temperature. The reaction solution was quenched with 10 mL of saturated aqueous sodium thiosulfate solution, and then separated using 30% ethyl acetate / hexane. The organic layer was dehydrated with anhydrous sodium sulfate, and the solvent was removed using an evaporator. The product was then purified by silica gel chromatography (developing solvent: dichloromethane:hexane=2:8) to obtain deuterated bromopyrene (53.18 mg).

[0142] The obtained deuterated bromopyrene (53.1 mg), sodium thiophenolate (120.9 mg), and 1,3-dimethyl-2-imidazolidinone (0.5 mL) were mixed and reacted for 14 hours with stirring at 200°C. The reaction solution was separated using 30% ethyl acetate / hexane and water as a solvent, and the solvent was removed using an evaporator. Subsequently, the mixture was purified by silica gel chromatography (developing solvent: dichloromethane:hexane=1:9) to obtain compound A-6 (16.85 mg).

[0143] (Synthesis of Compound A-7) Compound A-7 represented by the following formula was synthesized by the following method.

[0144] A mixture of 2-bromodibenzo[g,p]chrysene and 2,10-dibromodibenzo[g,p]chrysene (100 mg), S-potassium thioacetate (33.8 mg), 2-iodofluorene (86.0 mg), bis(dibenzylideneacetone)palladium(0) (15.9 mg), 1,1'-bis(diphenylphosphino)ferrocene (20.0 mg), and tripotassium phosphate (64.0 mg) was dissolved in anhydrous toluene (0.25 mL) and anhydrous acetone (0.12 mL) and placed under a nitrogen atmosphere. The mixture was reacted at 70°C for 3 hours, then heated to 110°C and reacted for 6 hours. The mixture was separated into pure water and dichloromethane as solvents, and the organic layer was dehydrated over anhydrous sodium sulfate, and the solvent was removed using an evaporator. The residue was purified by silica gel chromatography (dichloromethane:hexane=1:4) to obtain Compound A-7 (25.5 mg) as a white solid.

[0145] (Synthesis of Compound A-8) Compound A-8 represented by the following formula was synthesized by the following method.

[0146] A mixture of 2-bromodibenzo[g,p]chrysene and 2,10-dibromodibenzo[g,p]chrysene (100 mg, 0.246 mmol), S-potassium thioacetate (35.0 mg, 0.306 mmol), 2-iodonaphthalene (74.4 mg, 0.293 mmol), bis(dibenzylideneacetone)palladium(0) (22.4 mg, 0.039 mmol), 1,1'-bis(diphenylphosphino)ferrocene (20.1 mg, 0.0361 mmol), and tripotassium phosphate (65.2 mg, 0.307 mmol) was dissolved in anhydrous toluene (0.25 mL) and dry acetone (0.12 mL) and placed under a nitrogen atmosphere. The mixture was reacted at 70°C for 3 hours, then heated to 110°C and reacted for 6 hours. The mixture was separated using pure water and dichloromethane as a solvent, the organic layer was dehydrated with anhydrous sodium sulfate, and the solvent was removed using an evaporator. The residue was purified by silica gel chromatography (dichloromethane:hexane=1:4) to obtain Compound A-8 (25.5 mg) as a white solid.

[0147] (Synthesis of Compound A-9) Compound A-9 represented by the following formula was synthesized by the following method.

[0148] Dibenzo[g,p]chrysene (150.0 mg, 0.457 mmol) dissolved in anhydrous chlorobenzene (8.8 ml) was mixed with bromine (74.5 mg, 0.466 mmol) dissolved in anhydrous chlorobenzene (1.2 ml) dropwise and stirred at 110 °C for 20 hours under a nitrogen atmosphere. After cooling to room temperature, purified water was added and the mixture was extracted with chloroform. The organic layer was washed with purified water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. Purification by silica gel column chromatography (dichloromethane / hexane = 10 / 90) yielded 2-bromodibenzo[g,p]chrysene (168.9 mg, 90.7%) as a white solid.

[0149] 2-Bromodibenzo[g,p]chrysene (150.0 mg, 0.368 mmol) was mixed with 1,2-diphenyldiselane (80.5 mg, 0.258 mmol), [1,1′-Bis(diphenylphosphino)ferrocene]dichloropalladium(II) (13.5 mg, 0.0184 mmol), zinc (33.7 mg, 0.516 mmol), and anhydrous tetrahydrofuran (4.0 ml) and stirred at 67°C for 24 hours under a nitrogen atmosphere. After cooling to room temperature, purified water was added and the mixture was extracted with chloroform. The organic layer was washed with purified water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. Purification by silica gel column chromatography (dichloromethane / hexane = 12 / 88) afforded compound A-9 (54.9 mg, 30.8%) as a white solid.

[0150] Furthermore, for compound A-9, the density functional (DFT) method was used with Gaussian09 software, B3LYP was used as the functional, and 6-31G(d) was used as the basis function, and T １ The optimized structure in the state was calculated. When the HOMO and LUMO were displayed based on the calculation results under the condition of isovalue 0.03, the element X １ It was confirmed that the carbon atom directly bonded to the (selenium) atom has a HOMO and a LUMO.

[0151] (Synthesis of Compound A-10) Compound A-10 represented by the following formula was synthesized by the following method.

[0152] 9-Fluorenone (1363.6 mg, 7.6 mmol, 3.0 equiv.), 2-bromo-9-fluorenone (648.4 mg, 2.5 mmol, 1.0 equiv.), zinc powder (4219.9 mg, 64.5 mmol, 25 equiv.), and zinc chloride (2772.2 mg, 20.3 mmol, 8.0 equiv.) were dissolved in 25.0 mL of tetrahydrofuran and 25.0 mL of purified water and reacted at room temperature for 4 hours under atmospheric pressure. After confirming the disappearance of the starting material spots by thin-layer chromatography, the zinc powder was removed by suction filtration. The mixture was partitioned between saturated brine and dichloromethane, and the resulting organic layer was dehydrated over anhydrous sodium sulfate. The solvent was removed using a rotary evaporator to give brownish white 2-bromo-9H,9'H-[9,9'-bifluorene]-9,9'-diol (2093.1 mg).

[0153] 2-Bromo-9H,9'H-[9,9'-bifluorene]-9,9'-diol (1585.2 mg, 3.6 mmol) was dissolved in 35.5 mL of acetic acid and 1.8 mL of sulfuric acid and reacted at 85 °C for 4 hours under atmospheric pressure. After thin-layer chromatography confirmed that the starting material spots had disappeared, the reaction was terminated by neutralizing the acid with saturated aqueous sodium bicarbonate. The mixture was separated into saturated brine and dichloromethane, and the resulting organic layer was dehydrated over anhydrous sodium sulfate and the solvent was removed using an evaporator. Purification by silica gel chromatography (dichloromethane:hexane = 3:7) yielded white 2-bromo-10'H-spiro[fluorene-9,9'-phenanthren]-10'-one (429.9 mg, 28.3%) as the main component.

[0154] 2-Bromo-10'H-spiro[fluorene-9,9'-phenanthren]-10'-one (429.9 mg, 1.0 mmol, 1.0 equiv.) and granulated sodium borohydride (67.3 mg, 1.8 mmol, 1.8 equiv.) were dissolved in 6.0 mL of tetrahydrofuran and 6.0 mL of methanol and reacted at 60 °C for 2 hours under a nitrogen atmosphere. After confirming the disappearance of the starting material spots by thin-layer chromatography, the mixture was separated with saturated brine and dichloromethane, and the resulting organic layer was dehydrated over anhydrous sodium sulfate. The solvent was removed using an evaporator to yield white 2-bromo-10'H-spiro[fluorene-9,9'-phenanthren]-10'-ol (390.8 mg, 90.5%).

[0155] 2-Bromo-10'H-spiro[fluorene-9,9'-phenanthren]-10'-ol (390.8 mg, 0.92 mmol) was dissolved in 28.0 mL of acetic acid and 0.7 mL of sulfuric acid and reacted at 85 °C for 4 hours under atmospheric pressure. After thin-layer chromatography confirmed that the starting material spots had disappeared, the reaction was terminated by neutralizing the acid with saturated aqueous sodium bicarbonate. The mixture was separated into saturated brine and dichloromethane, and the resulting organic layer was dehydrated over anhydrous sodium sulfate and the solvent was removed using an evaporator. Purification by silica gel chromatography (dichloromethane:hexane = 1:9) yielded white 3-bromodibenzo[g,p]chrysene (259.7 mg, 69.4%) as the major component.

[0156] 9H-fluoren-9-one (1351.6 mg, 7.50 mmol), 2-bromo-9H-fluoren-9-one (647.8 mg, 2.50 mmol), zinc (4210.0 mg, 62.5 mmol), zinc chloride (2725.6 mg, 20.0 mmol), tetrahydrofuran (25 ml), and purified water (25 ml) were added to a 300 ml round-bottom flask and stirred at room temperature for 4 hours. After the reaction was complete, dichloromethane was added, and undissolved solids were removed by suction filtration. Purified water was added to the filtrate, and the mixture was extracted with dichloromethane. The organic layer was washed with purified water, dehydrated over sodium sulfate, and the solvent was removed by rotary evaporation to yield a white solid, 1 (2093.1 mg). Acetic acid (35.5 ml) and sulfuric acid (1.8 ml) were added to the white solid 1 (2093.1 mg) and stirred at 85°C for 4 hours. After cooling to room temperature, pure water was added and the mixture was extracted with dichloromethane. The organic layer was washed with pure water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. Purification by silica gel column chromatography (dichloromethane / hexane = 30 / 70) yielded white solid 2 (429.9 mg). Sodium borohydride (67.3 mg, 1.78 mmol), tetrahydrofuran (15 ml), and methanol (15 ml) were added to the white solid 2 (429.9 mg) and stirred at 60°C for 3 hours under a nitrogen atmosphere. After the reaction was complete, pure water was added and the mixture was extracted with dichloromethane. The organic layer was washed with pure water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator to yield white solid 3 (390.8 mg). Acetic acid (28 ml) and sulfuric acid (0.7 ml) were added to the white solid 3 (390.8 mg) and stirred at 85°C for 4 hours. After cooling to room temperature, pure water was added and the mixture was extracted with dichloromethane. The organic layer was washed with pure water, dehydrated with sodium sulfate, and the solvent was removed using a rotary evaporator.Purification by silica gel column chromatography (dichloromethane / hexane = 10 / 90) gave 3-bromodibenzo[g,p]chrysene (211.7 mg, 20.8%) as a white solid.

[0157] 3-Bromodibenzo[g,p]chrysene (142.0 mg, 0.349 mmol) was mixed with 1,2-diphenyldiselane (172.4 mg, 0.552 mmol), [1,1′-Bis(diphenylphosphino)ferrocene]dichloropalladium(II) (40.4 mg, 0.0552 mmol), zinc (72.2 mg, 1.10 mmol), and anhydrous tetrahydrofuran (11 ml) and stirred at 68°C for 16 hours under a nitrogen atmosphere. After cooling to room temperature, purified water was added and the mixture was extracted with chloroform. The organic layer was washed with purified water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. Purification by silica gel column chromatography (dichloromethane / hexane = 12 / 88) afforded compound A-10 (73.7 mg, 43.7%) as a white solid.

[0158] Furthermore, for compound A-10, the density functional (DFT) method was used with Gaussian09 software, B3LYP was used as the functional, and 6-31G(d) was used as the basis function. １ The optimized structure in the state was calculated. When the HOMO and LUMO were displayed based on the calculation results under the condition of isovalue 0.03, the element X １ It was confirmed that the carbon atom directly bonded to the (selenium) atom does not have either a HOMO or a LUMO.

[0159] (Preparation of Compound C-1) Compound C-1 represented by the following formula was obtained as a commercially available product.

[0160] (Synthesis of Compound C-1′) Compound C-1′ (represented by the following formula) was synthesized by substituting the hydrogen atoms of the polycyclic aromatic skeleton dibenzo[g,p]chrysene in Compound C-1 with deuterium (D) by the following method.

[0161] Dibenzo[g,p]chrysene (123.1 mg), palladium-activated carbon (Pd: 10% by mass) (124.8 mg), and heavy water (99.8% D) (25 mL) were reacted in an autoclave reaction vessel at 250°C for 12 hours. The mixture was then separated using pure water and chloroform as solvents, and the organic layer was dehydrated with anhydrous sodium sulfate. The residual carbon was removed by suction filtration, and the solvent was removed using a rotary evaporator. The mixture was then purified by silica gel chromatography (developing solvent: dichloromethane:hexane = 1:4), yielding white compound C-1' (92.80 mg).

[0162] (Preparation of Compound C-2) Compound C-2 represented by the following formula was obtained as a commercially available product.

[0163] (Preparation and Evaluation of Phosphorescent Material) In each example, a compound was selected from those described above (see Tables 1 to 6), and two powders were mixed so that the selected compound (powder) was 0.3% by mass and the benzophenone (powder) was 99.7% by mass. The mixture was then heated to 50°C to melt the benzophenone, and the selected compound was dissolved in the molten benzophenone to obtain a melt. The melt was then returned to room temperature and crystallized to prepare a phosphorescent material sample. Each sample was irradiated with 360 nm excitation light in the atmosphere using an absolute PL quantum yield apparatus ("C9920-02G" manufactured by Hamamatsu Photonics KK), and the irradiation was then stopped. At this time, a room-temperature phosphorescence spectrum immediately after the excitation light irradiation was stopped was obtained, and the peak wavelength λ ｐ The room temperature phosphorescence quantum yield Φ was also measured when the excitation light irradiation was stopped. Ｐ Furthermore, for each sample, the mean lifetime τ was measured under 360 nm excitation light in air using a time-resolved two-dimensional photodetector (Hamamatsu Photonics, PMA-12). ＰThe results are shown in Tables 1 to 6.

[0164]

[0165] Table 1 shows examples using compounds in which the polycyclic aromatic skeleton is dibenzochrysene (deuterium substituted), and S, a Group 16 element, is directly bonded to the polycyclic aromatic skeleton. In these examples, the S is bonded to a benzene skeleton at the terminal side. From Table 1, it can be seen that all of the examples have a long lifetime (τ Ｐ : 100 ms or more), and the brightness is significantly higher than that of the comparative example, and / or the peak wavelength λ ｐ It can be seen that Example 4 has a significantly larger Φ ｐ Although the peak wavelength λ ｐ In this regard, as can be seen from the relationships of (i), (ii), and (iii) above, the peak wavelength λ ｐ The larger the quantum yield Φ Ｐ In light of this, it can be said that Example 4 is also sufficiently superior.

[0166]

[0167] Table 2 shows examples using compounds in which the polycyclic aromatic skeleton is dibenzochrysene (deuterium substitution: not present) and S, a Group 16 element, is directly bonded to the polycyclic aromatic skeleton. From Table 2, it can be seen that the examples have long lifetimes (τ Ｐ : 100 ms or more), while the brightness is significantly higher than that of the comparative example.

[0168]

[0169] From the examples in Table 3, it can be seen that even when the elements directly bonded to the polycyclic aromatic skeleton are various Group 16 elements, the long lifetime (τ Ｐ It can be seen that the luminance is significantly higher than that of the comparative example while maintaining a low luminance (100 ms or more). Note that these results do not limit the present invention in any way.

[0170]

[0171] From the examples in Table 4, it can be seen that even when the polycyclic aromatic skeleton to which the Group 16 element is directly bonded is various, the long lifetime (τ Ｐ : 100 ms or more), the brightness is significantly higher than that of the comparative example, and the peak wavelength λ ｐ It can be seen that the difference is significantly large. However, these results do not limit the present invention in any way.

[0172]

[0173] From the examples in Table 5, it can be seen that even when various skeletons are further bonded to the terminal side of the Group 16 element directly bonded to the polycyclic aromatic skeleton, the long lifetime (τ Ｐ It can be seen that the luminance is significantly higher than that of the comparative example while maintaining a low luminance (100 ms or more). Note that these results do not limit the present invention in any way.

[0174]

[0175] From Table 6, in compound A, element X １ It can be seen that the luminance is further improved by directly bonding to the carbon atom on which the HOMO and / or LUMO of the polycyclic aromatic skeleton is carried.

[0176] (Synthesis of Compound A-11) Compound A-11 represented by the following formula was synthesized by the following method: Compound A-11 has a polycyclic aromatic skeleton consisting of a main polycyclic aromatic skeleton (dibenzochrysene) and a spacer aromatic skeleton (naphthalene) single-bonded to the main polycyclic aromatic skeleton.

[0177] Dibenzo[g,p]chrysene (420.0 mg, 1.28 mmol) dissolved in anhydrous chlorobenzene (12 ml) was mixed with bromine (204.4 mg, 1.28 mmol) dissolved in anhydrous chlorobenzene (0.33 ml) dropwise and stirred at 110 °C for 22 hours under a nitrogen atmosphere. After cooling to room temperature, purified water was added and the mixture was extracted with chloroform. The organic layer was washed with purified water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. Purification by silica gel column chromatography (chloroform / hexane = 10 / 90) yielded 2-bromodibenzo[g,p]chrysene (474.9 mg, 91.2%) as a white solid.

[0178] 2-Bromodibenzo[g,p]chrysene (500.0 mg, 1.23 mmol) was mixed with bis(pinacolato)diboron (498.8 mg, 1.96 mmol), potassium acetate (361.4 mg, 3.68 mmol), bis(diphenylphosphino)ferrocene]palladium(II) dichloromethane adduct (100.2 mg, 0.123 mmol), and 1,4-dioxane (14 mL) and stirred at 110 °C for 20 hours under a nitrogen atmosphere. After cooling to room temperature, pure water was added and the mixture was extracted with dichloromethane. The organic layer was washed with pure water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. Purification by silica gel column chromatography (dichloromethane / hexane = 30 / 70) gave 2-(dibenzo[g,p]chrysen-2-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (431.9 mg, 77.4%) as a pale yellow solid.

[0179] 2-(dibenzo[g,p]chrysen-2-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (400 mg, 0.880 mmol) was mixed with 1-bromo-8-iodonapthalene (439.7 mg, 1.32 mmol), potassium carbonate (243.3 mg, 1.76 mmol), tetrakis(triphenylphosphine)palladium(0) (50.9 mg, 0.0440 mmol), and anhydrous N,N-dimethylformamide (24 mL) and stirred at 110°C for 31 hours under a nitrogen atmosphere. After cooling to room temperature, purified water was added and the mixture was extracted with dichloromethane. The organic layer was washed with purified water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. The residue was purified by silica gel column chromatography (dichloromethane / hexane = 18 / 82) to give 2-(8-bromonaphthalen-1-yl)dibenzo[g,p]chrysene (318.9 mg, 67.9%) as a white solid.

[0180] 2-(8-bromonaphthalen-1-yl)dibenzo[g,p]chrysene (180 mg, 0.337 mmol) was mixed with 1,2-diphenyldiselane (210.6 mg, 0.675 mmol), [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II) (24.7 mg, 0.0337 mmol), zinc (55.2 mg, 0.844 mmol), and anhydrous tetrahydrofuran (4 ml) and stirred at 68°C for 90 hours under a nitrogen atmosphere. After cooling to room temperature, purified water was added and the mixture was extracted with dichloromethane. The organic layer was washed with purified water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. The residue was purified by silica gel column chromatography (dichloromethane / hexane = 18 / 82) to obtain compound A-11 (79.3 mg, 38.6%) as a white solid.

[0181] Furthermore, for compound A-11, the density functional (DFT) method was used with Gaussian09 software, B3LYP was used as the functional, and 6-311G(d,p) was used as the basis function. １ The optimized structure in the state was calculated. In this optimized structure, the two atoms (element X) obtained in the conformation １ The interatomic distance was measured from the coordinates of the carbon atom (Se, and the carbon atom to which the spacer aromatic skeleton of the main polycyclic aromatic skeleton is bonded) and was found to be 3.191 Å.

[0182] In addition, when points a, b, c, and d are specified as described above, the angle θ between the line segments ab and ac is １A In addition, in this compound A-11, the angle θ between the plane including points a, b, and c and the plane of the benzene ring constituting point a was 86.70°. ２A In addition, the angle θ between the line segments ca and cd of this compound A-11 was 81.49°. ３Ａ However, it was 91.15°.

[0183] (Synthesis of Compound A-12) Compound A-12 represented by the following formula was synthesized by the following synthesis method. Note that this compound A-12 has a polycyclic aromatic skeleton consisting of a main polycyclic aromatic skeleton (dibenzochrysene) and a spacer aromatic skeleton (benzene) single-bonded to the main polycyclic aromatic skeleton.

[0184] 2-(2-Bromophenyl)dibenzo[g,p]chrysene (95.7 mg, 0.198 mmol, 1.00 equiv.), diphenyl diselenide (66.9 mg, 0.214 mmol, 1.08 equiv.), [1,1'-bis(diphenylphosphino)ferrocene]palladium(II) (12.6 mg, 0.0172 mmol, 0.0870 equiv.), and zinc powder (36.3 mg, 0.555 mmol, 2.80 equiv.) were dissolved in 3.0 mL of THF and reacted at 70 °C under a nitrogen atmosphere for 24 h. After removing the zinc powder by suction filtration, the mixture was partitioned between saturated brine and dichloromethane. The organic phase was washed three times with brine, dried over Na2SO4, and filtered to obtain the crude material. The crude material was purified by column chromatography (silica gel, eluent = 10% DCM / hexane) to give (2-(dibenzo[g,p]chrysen-2-yl)phenyl)(phenyl)cerane (55.6 mg, 0.0994 mmol, 50.2%) as a white powder, compound A-12.

[0185] Furthermore, for compound A-12, the density functional (DFT) method was used with Gaussian09 software, B3LYP was used as the functional, and 6-31G(d) was used as the basis function, and T １ In this optimized structure, the element X １ The interatomic distance between (Se) and the carbon atom to which the spacer aromatic skeleton is bonded in the main polycyclic aromatic skeleton was measured and found to be 3.21 Å.

[0186] (Synthesis of Compound A-13) Compound A-13 represented by the following formula was synthesized by the following method. Note that this compound A-13 has a polycyclic aromatic skeleton consisting of a main polycyclic aromatic skeleton (dibenzochrysene) and a spacer aromatic skeleton (benzene) single-bonded to the main polycyclic aromatic skeleton.

[0187] 2-Bromodibenzo[g,p]chrysene (74.4 mg, 0.18 mmol, 1.0 equiv.), bis(pinacolato)diboron (74.9 mg, 0.29 mmol, 1.6 equiv.), [1,1'-Bis(diphenylphosphino)ferrocene] palladium(II) dichloride dichloromethane adduct (31.5 mg, 0.039 mmol, 0.22 equiv.), and potassium acetate (52.0 mg, 0.53 mmol, 2.9 equiv.) were dissolved in 2.0 mL of 1,4-dioxane and reacted at 80 °C for 24 hours under a nitrogen atmosphere. After the disappearance of the starting material spots by thin-layer chromatography, the mixture was separated using saturated brine and dichloromethane. The resulting organic layer was dehydrated over anhydrous sodium sulfate and the solvent was removed using an evaporator. The crude product was purified by silica gel chromatography (ethyl acetate:hexane = 1:4) to obtain light brown 2-(dibenzo[g,p]chrysen-2-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (43.5 mg) as the main component.

[0188] 2-(Dibenzo[g,p]chrysen-2-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (40.0 mg, 0.088 mmol, 1.0 equiv.), 1-bromo-2-iodobenzene, stabilized with copper chips (29.9 mg, 0.11 mmol, 1.3 equiv.), tetrakis(triphenylphosphine)palladium(0) (2.4 mg, 0.0021 mmol, 0.024 equiv.), and potassium carbonate (12.2 mg, 0.088 mmol, 1.0 equiv.) were dissolved in 5.0 mL of N,N-dimethylformamide and reacted at 110 °C for 24 hours under a nitrogen atmosphere. After confirming that the starting material spots had disappeared by thin-layer chromatography, the mixture was separated using saturated brine and dichloromethane. The resulting organic layer was dehydrated over anhydrous sodium sulfate and the solvent was removed using an evaporator. Purification by silica gel chromatography (dichloromethane:hexane = 1:4) yielded white 2-(2-bromophenyl)dibenzo[g,p]chrysene (23.4 mg, 55.0%) as the main component.

[0189] 2-(2-Bromophenyl)dibenzo[g,p]chrysene (23.4 mg, 0.049 mmol, 1.0 equiv.), diphenyl disulfide (8.8 mg, 0.037 mmol, 0.76 equiv.), [1,1'-bis(diphenylphosphino)ferrocene]palladium(II) (3.3 mg, 0.0029 mmol, 0.06 equiv.), and zinc powder (5.71 mg, 0.087 mmol, 1.8 equiv.) were dissolved in 2.0 mL of tetrahydrofuran and reacted at 70 °C for 24 hours under a nitrogen atmosphere. After confirming the disappearance of the starting material spots by thin-layer chromatography, the zinc powder was removed by suction filtration. The mixture was partitioned between saturated brine and dichloromethane. The resulting organic layer was dehydrated over anhydrous sodium sulfate, and the solvent was removed using an evaporator. The residue was purified by silica gel chromatography (dichloromethane:hexane=1:9) to obtain white compound A-13 (11.7 mg, 47.1%) as the main component.

[0190] Furthermore, for compound A-13, the density functional (DFT) method was used with Gaussian09 software, B3LYP was used as the functional, and 6-31G(d) was used as the basis function. １ In this optimized structure, the element X １ The interatomic distance between (S) and the carbon atom to which the spacer aromatic skeleton of the main polycyclic aromatic skeleton is bonded was measured to be 3.1494 Å.

[0191] In addition, when points a, b, c, and d are specified as described above, the angle θ between the line segments ab and ac is １A In addition, the angle θ between the plane including points a, b, and c and the plane of the benzene ring that constitutes point a was 64.42°. ２A In addition, the angle θ between the line segments ca and cd of this compound A-13 was 52.76°. ３Ａ However, it was 148.55°.

[0192] (Synthesis of Compound A-14) Compound A-14 represented by the following formula was synthesized by the following method. Note that this compound A-14 has a polycyclic aromatic skeleton consisting of a main polycyclic aromatic skeleton (dibenzochrysene) and a spacer aromatic skeleton (naphthalene) single-bonded to the main polycyclic aromatic skeleton.

[0193] 2-Bromodibenzo[g,p]chrysene (63.5 mg, 0.16 mmol, 1.0 equiv.), bis(pinacolato)diboron (73.1 mg, 0.29 mmol, 1.8 equiv.), [1,1'-Bis(diphenylphosphino)ferrocene]palladium(II) dichloride dichloromethane adduct (46.3 mg, 0.057 mmol, 0.36 equiv.), and potassium acetate (55.5 mg, 0.57 mmol, 3.6 equiv.) were dissolved in 2.0 mL of 1,4-dioxane and reacted at 80 °C for 24 hours under a nitrogen atmosphere. After the disappearance of the starting material spots by thin-layer chromatography, the mixture was separated using saturated brine and dichloromethane. The resulting organic layer was dehydrated over anhydrous sodium sulfate and the solvent was removed using an evaporator. The crude product was purified by silica gel chromatography (ethyl acetate:hexane = 1:4) to obtain light brown 2-(dibenzo[g,p]chrysen-3-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (43.5 mg) as the main component.

[0194] 2-(Dibenzo[g,p]chrysen-3-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (40.0 mg, 0.088 mmol, 1.0 equiv.), 1-Bromo-8-iodonaphthalene (37.3 mg, 0.11 mmol, 1.3 equiv.), tetrakis(triphenylphosphine)palladium(0) (2.0 mg, 0.0018 mmol, 0.020 equiv.), and potassium carbonate (23.7 mg, 0.088 mmol, 1.0 equiv.) were dissolved in 5.0 mL of N,N-dimethylformamide and reacted at 110 °C for 24 hours in the dark under a nitrogen atmosphere. After the disappearance of the starting material spots by thin-layer chromatography, the mixture was separated using saturated brine and dichloromethane. The resulting organic layer was dehydrated over anhydrous sodium sulfate and the solvent was removed using an evaporator. The crude product was purified by silica gel chromatography (dichloromethane:hexane=1:9) to obtain white 2-(8-bromonaphthalen-1-yl)dibenzo[g,p]chrysene (16.6 mg, 39.0%) as the main component.

[0195] 2-(8-Bromonaphthalen-1-yl)dibenzo[g,p]chrysene (16.6 mg, 0.034 mmol, 1.0 equiv.), diphenyl disulfide (20.2 mg, 0.093 mmol, 2.7 equiv.), [1,1'-bis(diphenylphosphino)ferrocene]palladium(II) (2.3 mg, 0.0031 mmol, 0.091 equiv.), and zinc powder (12.1 mg, 0.19 mmol, 5.6 equiv.) were dissolved in 2.0 mL of tetrahydrofuran and reacted at 70 °C for 24 hours under a nitrogen atmosphere. After thin-layer chromatography confirmed that the starting material spots had disappeared, the zinc powder was removed by suction filtration. The mixture was partitioned between saturated brine and dichloromethane. The resulting organic layer was dehydrated over anhydrous sodium sulfate, and the solvent was removed using an evaporator. The residue was purified by silica gel chromatography (dichloromethane:hexane=1:9) to obtain white compound A-14 (12.6 mg, 65.4%) as the main component.

[0196] Furthermore, for compound A-14, the density functional (DFT) method was used with Gaussian09 software, B3LYP was used as the functional, and 6-31G(d) was used as the basis function. １ In this optimized structure, the element X １ The interatomic distance between (S) and the carbon atom to which the spacer aromatic skeleton of the main polycyclic aromatic skeleton is bonded was measured to be 3.08 Å.

[0197] (Synthesis of Compound A-15) Compound A-15 represented by the following formula was synthesized by the following method. The polycyclic aromatic skeleton of this compound A-15 is composed of a main polycyclic aromatic skeleton (dibenzochrysene) and a spacer aromatic skeleton (naphthalene) single-bonded to the main polycyclic aromatic skeleton. In addition, this compound A-15 is composed of a spacer aromatic skeleton and an element X １ The number of (Se) is 2.

[0198] Dibenzo[g,p]chrysene (150.0 mg, 0.457 mmol) dissolved in anhydrous chlorobenzene (7.65 ml) was added dropwise with bromine (146.7 mg, 0.918 mmol) dissolved in anhydrous chlorobenzene (2.35 ml) and stirred at 110 °C for 18 hours under a nitrogen atmosphere. After cooling to room temperature, purified water was added and the mixture was extracted with chloroform. The organic layer was washed with purified water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. The mixture was washed with a chloroform / hexane mixture (10 / 90) to obtain a mixture of 2,10-dibromodibenzo[g,p]chrysene and 2,7,10-tribromodibenzo[g,p]chrysene (209.4 mg) as a white solid.

[0199] A mixture of 2,10-dibromodibenzo[g,p]chrysene and 2,7,10-tribromodibenzo[g,p]chrysene (200.0 mg) was added to bis(pinacolato)diboron (292.5 mg, 1.15 mmol), potassium acetate (201.8 mg, 2.06 mmol), bis(diphenylphosphino)ferrocene]palladium(II) dichloromethane adduct (67.2 mg, 0.0823 mmol), and 1,4-dioxane (7 mL) and stirred at 110 °C for 18 hours under a nitrogen atmosphere. After cooling to room temperature, purified water was added and the mixture was extracted with dichloromethane. The organic layer was washed with purified water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. Purification by silica gel column chromatography (chloroform / hexane = 40 / 60) gave a mixture of 2,10-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)dibenzo[g,p]chrysene and 2,2',2''-(dibenzo[g,p]chrysene-2,7,10-triyl)tris(4,4,5,5-tetramethyl-1,3,2-dioxaborolane) (162.0 mg) as a pale yellow solid.

[0200] A mixture of 2,10-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)dibenzo[g,p]chrysene and 2,2',2''-(dibenzo[g,p]chrysene-2,7,10-triyl)tris(4,4,5,5-tetramethyl-1,3,2-dioxaborolane) (70.0 mg) was added to 1-bromo-8-iodonapthalene (88.4 mg, 0.265 mmol), potassium carbonate (41.7 mg, 0.302 mmol), tetrakis(triphenylphosphine)palladium(0) (7.0 mg, 0.00606 mmol), and anhydrous N,N-dimethylformamide (4.2 ml) and stirred at 110°C for 12 hours under a nitrogen atmosphere. After cooling to room temperature, pure water was added and the mixture was extracted with dichloromethane. The organic layer was washed with pure water, dried over sodium sulfate, and then the solvent was removed using a rotary evaporator. Purification by silica gel column chromatography (dichloromethane / hexane = 20 / 80) afforded 2,10-bis(8-bromonaphthalen-1-yl)dibenzo[g,p]chrysene (10.5 mg) and 2,7,10-tris(8-bromonaphthalen-1-yl)dibenzo[g,p]chrysene (23.1 mg) as pale yellow solids. The reaction yields from dibenzo[g,p]chrysene were 3.1% and 5.4%, respectively.

[0201] 2,10-bis(8-bromonaphthalen-1-yl)dibenzo[g,p]chrysene (10.0 mg, 0.0135 mmol) was mixed with 1,2-diphenyldiselane (6.8 mg, 0.0218 mmol), [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II) (0.99 mg, 0.00135 mmol), zinc (1.8 mg, 0.0275 mmol), and anhydrous tetrahydrofuran (0.5 ml) and stirred at 68°C for 13 hours under a nitrogen atmosphere. After cooling to room temperature, purified water was added and the mixture was extracted with dichloromethane. The organic layer was washed with purified water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. The residue was purified by silica gel column chromatography (dichloromethane / hexane = 25 / 75) to obtain compound A-15 (3.7 mg, 30.7%) as a pale yellow solid.

[0202] Furthermore, for compound A-15, the density functional (DFT) method was used with Gaussian09 software, B3LYP was used as the functional, and 6-311G(d,p) was used as the basis function. １ In this optimized structure, the element X １ The interatomic distances between (Se) and the carbon atom to which the spacer aromatic skeleton is bonded in the main polycyclic aromatic skeleton were measured to be 3.09 Å and 3.19 Å.

[0203] (Synthesis of Compound A-16) Compound A-16 represented by the following formula was synthesized by the following method. The polycyclic aromatic skeleton of this compound A-16 is composed of a main polycyclic aromatic skeleton (dibenzochrysene) and a spacer aromatic skeleton (naphthalene) single-bonded to the main polycyclic aromatic skeleton. In addition, this compound A-16 is composed of a spacer aromatic skeleton and an element X １ The number of (Se) is 3.

[0204] 2,7,10-tris(8-bromonaphthalen-1-yl)dibenzo[g,p]chrysene (20.0 mg, 0.0212 mmol) synthesized in the previous section was added to 1,2-diphenyldiselane (14.6 mg, 0.0466 mmol), [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II) (1.6 mg, 0.00219 mmol), zinc (3.5 mg, 0.0535 mmol), and anhydrous tetrahydrofuran (0.5 ml) and stirred at 68°C for 17 hours under a nitrogen atmosphere. After cooling to room temperature, pure water was added and the mixture was extracted with dichloromethane. The organic layer was washed with pure water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. The residue was purified by silica gel column chromatography (dichloromethane / hexane = 30 / 70) to obtain compound A-16 (14.6 mg, 58.8%) as a pale yellow solid.

[0205] Furthermore, for compound A-16, the density functional (DFT) method was used with Gaussian09 software, B3LYP was used as the functional, and 6-311G(d,p) was used as the basis function. １ In this optimized structure, the element X １ The interatomic distances between (Se) and the carbon atom to which the spacer aromatic skeleton is bonded in the main polycyclic aromatic skeleton were measured to be 3.05 Å, 3.19 Å, and 3.19 Å.

[0206] (Synthesis of Compound A-17) Compound A-17 represented by the following formula was synthesized by the following method. The polycyclic aromatic skeleton of this compound A-17 is composed of a main polycyclic aromatic skeleton (dibenzochrysene) and a spacer aromatic skeleton (naphthalene) single-bonded to the main polycyclic aromatic skeleton. In addition, this compound A-17 is composed of a spacer aromatic skeleton and an element X １ The number of (Se) is 4.

[0207] Dibenzo[g,p]chrysene (200.0 mg, 0.609 mmol) dissolved in anhydrous chlorobenzene (11 ml) was mixed with bromine (486.6 mg, 3.04 mmol) dissolved in anhydrous chlorobenzene (1.6 ml) dropwise and stirred at 110 °C for 26 hours under a nitrogen atmosphere. After cooling to room temperature, pure water was added and the mixture was extracted with chloroform. The organic layer was washed with pure water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. 2,7,10,15-tetrabromodibenzo[g,p]chrysene (348.2 mg, 88.8%) was obtained as a white solid by washing with a mixed solvent of chloroform and hexane (10 / 90).

[0208] 2,7,10,15-tetrabromodibenzo[g,p]chrysene (200.0 mg, 0.311 mmol) was added to bis(pinacolato)diboron (394.3 mg, 1.55 mmol), potassium acetate (213.3 mg, 2.17 mmol), bis(diphenylphosphino)ferrocene]palladium(II) dichloromethane adduct (25.4 mg, 0.0311 mmol), and 1,4-dioxane (7 mL) and stirred at 110 °C for 18 hours under a nitrogen atmosphere. After cooling to room temperature, purified water was added and the mixture was extracted with ethyl acetate. The organic layer was washed with purified water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. Purification by silica gel column chromatography (ethyl acetate / hexane = 8 / 92) gave 2,7,10,15-tetrakis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)dibenzo[g,p]chrysene (167.3 mg, 64.7%) as a pale yellow solid.

[0209] 2,7,10,15-tetrakis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)dibenzo[g,p]chrysene (150 mg, 0.180 mmol) was mixed with 1-bromo-8-iodonapthalene (300.1 mg, 0.901 mmol), potassium carbonate (137.0 mg, 0.991 mmol), tetrakis(triphenylphosphine)palladium(0) (16.7 mg, 0.0144 mmol), and anhydrous N,N-dimethylformamide (6.3 mL) and stirred at 110°C for 12 hours under a nitrogen atmosphere. After cooling to room temperature, purified water was added and the mixture was extracted with chloroform. The organic layer was washed with purified water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. Purification by silica gel column chromatography (dichloromethane / hexane = 20 / 80) gave 2,7,10,15-tetrakis(8-bromonaphthalen-1-yl)dibenzo[g,p]chrysene (62.5 mg, 30.2%) as a pale yellow solid.

[0210] 2,7,10,15-tetrakis(8-bromonaphthalen-1-yl)dibenzo[g,p]chrysene (55.0 mg, 0.0479 mmol) was mixed with 1,2-diphenyldiselane (44.8 mg, 0.144 mmol), [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium(II) (3.5 mg, 0.00479 mmol), zinc (11.0 mg, 0.168 mmol), and anhydrous tetrahydrofuran (2.2 ml) and stirred at 68°C for 18 hours under a nitrogen atmosphere. After cooling to room temperature, purified water was added and the mixture was extracted with dichloromethane. The organic layer was washed with purified water, dehydrated over sodium sulfate, and the solvent was removed using a rotary evaporator. The residue was purified by silica gel column chromatography (dichloromethane / hexane = 35 / 65) to obtain compound A-17 (41.0 mg, 58.9%) as a pale yellow solid.

[0211] Furthermore, for compound A-17, the density functional (DFT) method was used with Gaussian09 software, B3LYP was used as the functional, and 6-311G(d,p) was used as the basis function. １ In this optimized structure, the element X １ The interatomic distances between (Se) and the carbon atoms to which the spacer aromatic skeleton is bonded in the main polycyclic aromatic skeleton were measured to be 3.048 Å (two vertical positions) and 3.195 Å (two horizontal positions).

[0212] In addition, when points a, b, c, and d are specified as described above, the angle θ between the line segments ab and ac is １A In addition, the angle θ between the plane including points a, b, and c and the plane of the benzene ring that constitutes point a was 88.78°. ２A In addition, the angle θ between the line segments ca and cd of this compound A-17 was 77.42°. ３Ａ However, it was 163.1°.

[0213] (Synthesis of Compound B-1) Compound B-1 represented by the following formula was synthesized by the following method. ２ A ring skeleton (benzene) bonded to a polycyclic aromatic skeleton (dibenzochrysene) via (S) is connected to an element X. １ In addition, this compound B-1 has an element X (Se) directly bonded thereto. １ (Se) is further bonded to an aromatic skeleton (another benzene) other than the cyclic skeleton (benzene).

[0214] 2-bromodibenzo[g,p]chrysene (999 mg, 2.45 mmol, 1.0 equiv.), S-Potassium Thioacetate (416.8 mg, 3.65 mmol, 1.5 equiv.), 1-bromo-2-iodobenzene(0.46 mL, 3.67 mmol, 1.5 equiv.), Bis(dibenzylideneacetone) palladium(0) (176 mg, 0.306 mmol, 0.12 equiv.), 1,1'-Bis(diphenylphosphino)ferrocene (239 mg, 0.431 mmol, 0.18 equiv.), Tripotassium Phosphate (773 mg, 3.64 mmol, 1.5 equiv.) with dry toluene (3.0 mL) and dry acetone (1.5 mL) under nitrogen atmosphere. The mixture was dissolved in 1 mL of 1-bromo-2-iodobenzene and 1-bromo-2-iodobenzene (0.46 mL, 3.67 mmol, 1.5 equiv.) was added dropwise. The mixture was heated at 70 °C for 3.5 h with stirring under a nitrogen atmosphere, then heated at 110 °C for 6.5 h. The reaction mixture was cooled to room temperature and concentrated by removing the acetone under reduced pressure. The product was then mixed with chloroform and washed three times with water. The organic layer was dehydrated over Na2SO4, and the solvent was removed under reduced pressure and concentrated. Purification by silica gel column chromatography (dichloromethane:hexane = 1:9) afforded (2-bromophenyl)(dibenzo[g,p]chrysen-2-yl)sulfane (294 mg, 23.2%) as a white solid.

[0215] (2-Bromophenyl)(dibenzo[g,p]chrysen-2-yl)sulfane (230 mg, 0.446 mmol, 1.0 equiv.), diphenyl diselenide (110 mg, 0.351 mmol, 0.79 equiv.), [1,1′-Bis(diphenylphosphino)ferrocene]dichloropalladium(II) (16.5 mg, 0.0226 mmol, 0.051 equiv.), and zinc (42.3 mg, 0.647 mmol, 1.4 equiv.) were dissolved in dry tetrahydrofuran (0.45 mL) under a nitrogen atmosphere. The mixture was heated at 80 °C for 23 h with stirring under a nitrogen atmosphere. After cooling to room temperature, the product was mixed with a 1:4 mixture of ethyl acetate and hexane, washed three times with water, and the organic layer was dehydrated over NaSO. The solvent was then removed under reduced pressure and concentrated. Purification by silica gel column chromatography (dichloromethane:hexane = 1:9 → 1:4) afforded compound B-1 (66.5 mg, 23.2%) as a white solid.

[0216] Furthermore, for compound B-1, the density functional (DFT) method was used with Gaussian09 software, B3LYP was used as the functional, and 6-31G(d) was used as the basis function, and T １ In this optimized structure, the element X １ (Se) and element X ２ The interatomic distance of (S) was measured to be 3.2935 Å.

[0217] In addition, when points e, f, g, and h are specified as described above, the angle θ between the line segments ef and eg is １Ｂ In addition, the angle θ between the line segments ge and gh of this compound B-1 was 60.72°. ３Ｂ However, it was 151.97°.

[0218] (Preparation and Evaluation of Phosphorescent Materials) In each example, a compound was selected from those described above (see Tables 7 to 9), and two powders were mixed so that the selected compound (powder) was 0.3% by mass and the β-estradiol (powder) was 99.7% by mass. The mixture was then heated to 240°C to melt the β-estradiol, and the selected compound was dissolved in the molten β-estradiol to obtain a melt. The melt was then rapidly cooled to room temperature to vitrify the mixture, thereby preparing a phosphorescent material sample. Each sample was irradiated with 360 nm excitation light in the atmosphere using an absolute PL quantum yield analyzer ("C9920-02G" manufactured by Hamamatsu Photonics KK), and the irradiation was then stopped. At this time, a room-temperature phosphorescence spectrum immediately after the excitation light irradiation was stopped was obtained, and the peak wavelength λ ｐ The room temperature phosphorescence quantum yield Φ was also measured when the excitation light irradiation was stopped. Ｐ Furthermore, for each sample, the mean lifetime τ was measured under 350 nm excitation light in air using a time-resolved two-dimensional photodetector (Hamamatsu Photonics, PMA-12). Ｐ The results are shown in Tables 7 to 9.

[0219]

[0220] From Table 7, in compound A1, element X １ It can be seen that when the interatomic distance between the carbon atom to which the spacer aromatic skeleton is bonded in the main polycyclic aromatic skeleton is large to a certain extent (there is a through space), the brightness is further improved due to the through-space interaction.

[0221]

[0222] From Table 8, it can be seen that in Compound A1, the luminance is further improved as the number of through spaces increases.

[0223]

[0224] From Table 9, it is found that compound B (i.e., a compound in which the polycyclic aromatic skeleton and the cyclic skeleton are formed by adding an element X selected from S, P, N, or Si) ２ and is bonded via a group 16 element X of the periodic table. １The examples using compounds in which the cyclic skeleton is directly bonded to the cyclic skeleton also showed long life (τ Ｐ : 100 ms or more), while the brightness is significantly higher than that of the comparative example.

[0225] According to the present invention, it is possible to provide a phosphorescent material that exhibits room-temperature phosphorescence in the red or near-infrared region, and that exhibits long-life and high brightness phosphorescence. Furthermore, according to the present invention, it is possible to provide phosphorescent particles, dispersions, and display media using the above phosphorescent material.

Claims

1. A polycyclic aromatic skeleton or an element X selected from S, P, N, or Si ２ The cyclic skeleton is bonded to the polycyclic aromatic skeleton via a group 16 element of the periodic table, X １ is directly bonded to the compound (the element X １ may form a ring together with other elements, provided that in this case, the ring does not include the X １ and carbon C only bonded to each other.

2. The polycyclic aromatic skeleton includes the element X. １ In the compound in which the element X is directly bonded, １ is further bonded to an aromatic skeleton other than the polycyclic aromatic skeleton.

3. The polycyclic aromatic skeleton includes the element X. １ In the compound in which the element X is directly bonded, １ is directly bonded to a carbon atom on which the highest occupied molecular orbital (HOMO) and / or the lowest unoccupied molecular orbital (LUMO) of the polycyclic aromatic skeleton is located.

4. The polycyclic aromatic skeleton is provided with the element X. １ is directly bonded to the polycyclic aromatic skeleton, the polycyclic aromatic skeleton consisting of a main polycyclic aromatic skeleton and a spacer aromatic skeleton that is single-bonded to the main polycyclic aromatic skeleton.

5. The polycyclic aromatic skeleton includes the element X. １ In the compound in which the element X is directly bonded, １ is directly bonded to the spacer aromatic skeleton.

6. The polycyclic aromatic skeleton includes the element X. １ In the compound in which the element X is directly bonded, １ and the carbon atom to which the spacer aromatic skeleton is bonded in the main polycyclic aromatic skeleton is 3.050 Å or more and 3.500 Å or less.

7. The polycyclic aromatic skeleton is provided with the element X. １ In the compound in which the spacer aromatic skeleton and the element X are directly bonded, １ The number of each element X is 2 or more, １ is directly bonded to each spacer aromatic skeleton, and each element X １ and the carbon atom to which the spacer aromatic skeleton is bonded in the main polycyclic aromatic skeleton are both 3.000 Å or more and 3.500 Å or less.

8. The polycyclic aromatic skeleton is provided with the element X. １ is directly bonded to the compound, the energy level of the lowest triplet state of the spacer aromatic skeleton is higher than the energy level of the lowest triplet state of the main polycyclic aromatic skeleton.

9. The polycyclic aromatic skeleton is provided with the element X. １ is directly bonded to the main polycyclic aromatic skeleton, a carbon atom in the main polycyclic aromatic skeleton that is single-bonded to the spacer aromatic skeleton is designated as point a, a carbon atom in the spacer aromatic skeleton that is single-bonded to the main polycyclic aromatic skeleton is designated as point b, and the element X １ When point a and point b are defined as point c, the angle θ between the line segment ab connecting point a and point b and the line segment ac connecting point a and point c is １A The luminous material according to any one of claims 4 to 8, wherein the angle is 60.0° or more and 90.0° or less.

10. The polycyclic aromatic skeleton is provided with the element X. １ is directly bonded to the spacer aromatic skeleton, a carbon atom in the main polycyclic aromatic skeleton that is single-bonded to the spacer aromatic skeleton is designated as point a, a carbon atom in the spacer aromatic skeleton that is single-bonded to the main polycyclic aromatic skeleton is designated as point b, and the element X directly bonded to the spacer aromatic skeleton is designated as point a. １ When point a is set as point c, the angle θ between the plane including points a, b, and c and the plane of the benzene ring that constitutes point a ２A The luminous material according to any one of claims 4 to 9, wherein the angle is 50.0° or more and 85.0° or less.

11. The polycyclic aromatic skeleton is provided with the element X. １ In the compound in which the element X is directly bonded, １ is further bonded to an aromatic skeleton other than the polycyclic aromatic skeleton, and the element X in the aromatic skeleton １ When the carbon atom to which is bonded is defined as point d, the angle θ formed by the line segment ca connecting point c and point a and the line segment cd connecting point c and point d is ３Ａ The phosphorescent material according to claim 9 or 10, wherein the angle is 85.0° or more and 165.0° or less.

12. The element X ２ The element X is bonded to a cyclic skeleton bonded to a polycyclic aromatic skeleton via １ In the compound in which the element X is directly bonded, １ is further bonded to an aromatic skeleton other than the cyclic skeleton.

13. The element X ２ The element X is bonded to a cyclic skeleton bonded to a polycyclic aromatic skeleton via １ In the compound in which the element X is directly bonded, １ and the element X ２ The luminous material according to any one of claims 1 to 12, wherein the interatomic distance between is 3.200 Å or more and 3.350 Å or less.

14. The element X ２ The element X is bonded to a cyclic skeleton bonded to a polycyclic aromatic skeleton via １ is directly bonded to the compound, the energy level of the lowest triplet state of the cyclic skeleton is higher than the energy level of the lowest triplet state of the polycyclic aromatic skeleton.

15. The element X ２ The element X is bonded to a cyclic skeleton bonded to a polycyclic aromatic skeleton via １ In the compound in which the element X is directly bonded, ２ is set as point e, and the element X in the cyclic skeleton ２ The carbon atom bonded to the element X is defined as point f. １ When point g is the angle θ between the line segment ef connecting points e and f and the line segment eg connecting points e and g, １Ｂ The luminous material according to any one of claims 1 to 14, wherein the angle is 55.0° or more and 65.0° or less.

16. The element X ２ The element X is bonded to a cyclic skeleton bonded to a polycyclic aromatic skeleton via １ In the compound in which the element X is directly bonded, １ is further bonded to an aromatic skeleton other than the cyclic skeleton, and the element X in the aromatic skeleton １ When the carbon atom to which is bonded is defined as point h, the angle θ formed by the line segment ge connecting point g and point e and the line segment gh connecting point g and point h is ３Ｂ The light-storing material according to claim 15, wherein the angle is 140.0° or more and 160.0° or less.

17. The phosphorescent material according to claim 1, wherein the polycyclic aromatic skeleton is selected from the following:

18. The luminous material according to any one of claims 1 to 17, wherein the content of the compound is 0.001% by mass or more and 30% by mass or less.

19. A luminous material for a living organism, wherein the luminous material according to any one of claims 1 to 18 is introduced into a living organism and used to identify the characteristics of the organism.

20. A luminous particle, characterized in that the luminous material according to any one of claims 1 to 18 or the luminous material for living organisms according to claim 19 is made into a particle and the surface of the particle is coated with a polymer.

21. A dispersion liquid characterized by being obtained by dispersing the phosphorescent particles according to claim 20 in a solvent.

22. A display medium characterized by using a film made of the phosphorescent material according to any one of claims 1 to 18.

Images