Compound having a fluorene skeleton and method for producing the same

Abstract

To provide a compound having a novel fluorene skeleton which has a low content of a specific metal such as a palladium content in a raw material alcohol and is excellent in the hue and various characteristics (optical characteristics, heat resistance, moldability, etc.) of the raw material and a resin using the raw material, and to provide a method for producing the same.SOLUTION: There is provided a compound having a fluorene skeleton with the content of sulfur element being 200 ppm or less, represented by the following formula (1) (where R1 is H, a halogen atom or a hydrocarbon group optionally including a C1-12 aromatic group; Ar1 and Ar2 independently represent a C6-12 substituted / unsubstituted aromatic group; L1 is a C1-12 alkylene group; m1 and n1 independently represent an integer of 0-4; m2 and n2 independently represent an integer of 0-3; m1+m2≥1; m1+n1≤4; m2+n2≤3; o1 and o2 independently represent an integer of 0-5).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a compound having a fluorene skeleton, which is suitable as a monomer for forming a thermoplastic resin constituting an optical member such as an optical lens or an optical film, and is suitable as a raw material for a thermoplastic resin having a high refractive index, low birefringence, and an excellent balance between heat resistance and moldability, and to a method for producing the compound. [Background technology]

[0002] In recent years, thermoplastic resin materials such as polycarbonates, polyesters, and polyester carbonates, which are made from alcohols with a fluorene skeleton, such as 9,9-bis(4-(2-hydroxyethoxy)phenyl)fluorene (BPEF), have been attracting attention as optical components such as optical lenses and optical sheets due to their excellent optical properties, heat resistance, and moldability.

[0003] For example, Patent Document 1 discloses a polycarbonate resin made from an alcohol having a BPEF skeleton. However, although the refractive index of the polycarbonate resin using this alcohol is described as 1.64, rapid technological innovation in recent years has led to demand for further improvements in this property. Therefore, in an effort to achieve a higher refractive index, Patent Document 2 develops a thermoplastic resin made from 9,9-bis[4-(2-hydroxyethoxy)-3-phenylphenyl]fluorene (BOPBPEF), but the resin described in this patent document still has room for improvement in refractive index. Furthermore, Patent Document 3 describes a high refractive index resin made from 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]fluorene (BNEF), but while the refractive index is high, the resin also suffers from high birefringence, which poses a major problem when used in transparent materials such as optical lenses. As described above, there is a trade-off between a high refractive index and a low birefringence, and it has been difficult to achieve both properties with conventional polycarbonate or polyester resins.

[0004] Incidentally, a method for producing 9,9-bis(4-(2-hydroxyethoxy)phenyl)fluorene (BPEF) has been disclosed in which 9-fluorenone and 2-phenoxyethanol are dehydrated and condensed using sulfuric acid and thiols as catalysts (Non-Patent Document 1). Similarly, a method for producing 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]fluorene (BNEF) has been disclosed in which fluorenone and 2-naphthoxyethanol are dehydrated and condensed using sulfuric acid and thiols as catalysts, similar to the method for producing BPEF (Patent Document 4). Furthermore, a method for producing 9,9-bis[4-(2-hydroxyethoxy)-3-phenylphenyl]fluorene (BOPBPEF) has been disclosed in which fluorenone and 2-(2-biphenylyloxy)ethanol are dehydrated and condensed using sulfuric acid and thiols as catalysts, similar to the method for producing BPEF and BNEF (Patent Document 5). In addition, a method for producing 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]fluorene (BNEF) has been disclosed (Patent Document 6), which involves dehydration condensation of 9-fluorenone and 2-naphthol in toluene and γ-butyrolactone under reduced pressure using phosphotungstic acid and n-dodecyl mercaptan instead of sulfuric acid as acid catalysts, followed by addition of ethylene carbonate directly without purification. However, both methods require large amounts of sulfuric acid or a small amount of n-dodecyl mercaptan as a sulfur source as an acid catalyst, necessitating complex post-reaction purification procedures such as neutralization and purification, and generating large amounts of neutralization wastewater. Furthermore, catalyst-derived sulfur components are mixed into the product, causing problems such as discoloration, reduced stability, and reduced purity. Furthermore, repeated purification procedures to remove sulfur components are required to obtain high-purity products, such as optical resin materials, making these methods less industrially advantageous. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2007 / 142149 Brochure [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-86265 [Patent Document 3] Japanese Patent Application Publication No. 2017-171885 [Patent Document 4] Japanese Patent Application Laid-Open No. 2016-79405 [Patent Document 5] Japanese Patent Application Laid-Open No. 2009-256342 [Patent Document 6] JP 2019-1780 A [Non-patent literature]

[0006] [Non-Patent Document 1] Chemistry Letters, 1998, pp. 1055-1056 Summary of the Invention [Problem to be solved by the invention]

[0007] The molecular design of the compound of formula (1) in this invention consists of two steps. However, when the inventors used the methods described in the above-mentioned patent documents, the reaction either did not occur at all or proceeded at a slow rate, making them industrially disadvantageous. Furthermore, if a large amount of catalyst was used or if activated carbon treatment or a similar metal removal treatment was not performed, the white compound having a fluorene skeleton represented by formula (1) below was contaminated with black particles derived from the palladium-based catalyst, resulting in a deterioration in the color of the alcohol compound. Furthermore, the high content of impurities containing sulfur and bromine sometimes worsened the color of the alcohol compound or resulted in poor reaction when the alcohol was used as a raw material for polymerization.

[0008] Therefore, the present invention has been achieved as a result of investigations aimed at solving the above-mentioned problems of the prior art, and aims to provide a novel compound having a fluorene skeleton, which has a low content of sulfur-containing impurities in the raw material alcohol, more preferably a low content of specific metals such as palladium and a low content of impurities containing bromine, and which provides raw materials and resins made from the raw materials with excellent hue and various properties (optical properties, heat resistance, moldability, etc.), and a method for producing the same. [Means for solving the problem]

[0009] The present invention has been achieved as a result of investigations aimed at solving the above-mentioned problems of the prior art, and aims to provide a compound having a fluorene skeleton and having a certain quality and being excellent as a polymer raw material, and a method for producing the same. Specifically, the present invention relates to the following compound having a fluorene skeleton and a method for producing the same.

[0010] [1] A compound having a fluorene skeleton represented by the following formula (1), in which the content of sulfur element in the compound having a fluorene skeleton is 200 ppm or less: [ka] (In the formula, R 1 is a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 12 carbon atoms which may contain an aromatic group; Ar 1 and Ar 2 each independently represents an aromatic group having 6 to 12 carbon atoms which may have a substituent; L 1 is an alkylene group having 1 to 12 carbon atoms, m1 and n1 are the same or different and represent an integer of 0 to 4, m2 and n2 are the same or different and represent an integer of 0 to 3, and m1+m2≧1, provided that m1+n1 is an integer of 4 or less, and m2+n2 is an integer of 3 or less, and o1 and o2 each independently represent an integer of 0 to 5.

[0011] [2] The compound having a fluorene skeleton according to item 1 above, wherein the content of palladium element in the compound having a fluorene skeleton represented by formula (1) satisfies the following formula (2): 0 ≦ Pd ≦ 50 ppm (2) [3] The compound having a fluorene skeleton according to the above item 1 or 2, wherein the APHA of a 5 wt % solution of the compound represented by formula (1) in dimethylformamide is 500 or less. [4] The compound having a fluorene skeleton according to any one of items 1 to 3 above, wherein the compound represented by formula (1) has a bromine element content of 150 ppm or less.

[0012] [5] The compound having a fluorene skeleton according to any one of items 1 to 4 above, wherein the formula (1) is one of the following formulae (1a) to (1d): [ka] [ka] [ka] [ka] (In the formula, R 2 ~R 13 each independently represents a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 12 carbon atoms which may contain an aromatic group. 1 , Ar 2 , L 1 and o1 are the same as in formula (1).

[0013] [6] The compound having a fluorene skeleton according to item 5 above, wherein the formula (1) is the formula (1b). [7] Ar in the formula (1) 1 and Ar 2 7. The compound having a fluorene skeleton according to any one of items 1 to 6 above, wherein is a phenyl group or a naphthyl group.

[0014] [8] The compound having a fluorene skeleton according to any one of items 1 to 7 above, wherein the formula (1) is a compound represented by formula (1-b). [ka] [9] The compound according to the above item 8, wherein the content of diphenylfluorenone in the compound represented by formula (1) is 0.2% or less.

[0015]

[10] A method for producing a compound having a fluorene skeleton represented by the above formula (1), comprising at least the following steps 1 to 3: Step 1: A step of reacting a fluorenone represented by the following formula (3) with an alcohol represented by the following formula (4) in a reaction solvent in the presence of an acid catalyst to obtain a compound represented by the following formula (5): Step 2: A step of reacting a compound represented by the following formula (5) with ethylene carbonate in a reaction solvent in the presence of a base to obtain a compound represented by the following formula (6): Step 3: A step of reacting a compound represented by the following formula (6) with a boronic acid represented by the following formula (7) or (8) in a reaction solvent in the presence of a base and a palladium catalyst to obtain a compound represented by the above formula (1). [ka] (In the formula, X 1 is a substituent at the 1st, 2nd, 3rd or 4th position, and X 2 is a substituent at the 5th, 6th, 7th or 8th position and represents a halogen atom. [ka] (In the formula, p1 and p2 are the same or different and are integers of 0 to 4; R 1 , n1 and n2 are the same as in formula (1). [ka] (In the formula, X 1 and X 2 is the same as the above formula (3). 1 where p1 and p2 are the same as in formula (4), and n1 and n2 are integers from 0 to 3. [ka] (In the formula, X 1 and X 2 is the same as the above formula (3). 1 , L 1 , m1, m2, n1, n2, o1 and o2 are the same as in equation (1). [ka] [ka] (wherein Y is an aromatic group, R 14 represents a hydrogen atom, an alkyl group, an alkenyl group, an alkoxy group, or a halogen atom. l is 0, 1, or 2. When l=2, R 14 may be the same or different.)

[0016]

[11] The method according to the above item 10, wherein steps 1 and 2 are carried out in one pot without isolating the compound represented by formula (5).

[12] The production method according to the above item 10, wherein steps 1 to 3 are carried out in one pot without isolating the compounds represented by formulae (5) and (6).

[13] The method for producing a compound having a fluorene skeleton according to the above item 10, wherein the compound represented by formula (3) is 2,7-dibromofluorenone.

[14] The method for producing a compound having a fluorene skeleton according to the above item 10, wherein the compound represented by formula (7) is phenylboronic acid.

[15] The method for producing a compound having a fluorene skeleton according to the above item 10, wherein the compound represented by formula (8) is an anhydride of phenylboronic acid.

[16] The method for producing a compound having a fluorene skeleton according to the above item 10, wherein the compound represented by formula (4) is 2-naphthol.

[17] The method for producing a compound having a fluorene skeleton according to the above item 10, wherein the compound represented by formula (5) is 9,9'-bis(6-hydroxy-2-naphthyl)-2,7-dibromofluorene.

[18] The method for producing a compound having a fluorene skeleton according to the preceding item 10, wherein the palladium catalyst used in step 3 is a palladium catalyst represented by tetrakis(triphenylphosphine)palladium and / or Pd / SiO2.

[19] The method for producing a compound having a fluorene skeleton according to the above item 10, wherein the base used in step 3 is potassium carbonate and / or sodium carbonate.

[20] The method for producing a compound having a fluorene skeleton according to the above item 10, wherein a mixed solvent of toluene and ethanol is used as the reaction solvent in step 3.

[21] The method for producing a compound having a fluorene skeleton according to item 10, wherein the acid catalyst used in step 1 is a heteropolyacid composed of phosphoric acid or silicic acid and an oxyacid ion of at least one element selected from vanadium, molybdenum, and tungsten.

[22] The method for producing a compound having a fluorene skeleton according to the above item 10, wherein in step 1, a compound having a thiol group is used in combination with an acid catalyst.

[23] The method for producing a compound having a fluorene skeleton according to the above item 10, wherein a mixed solvent of toluene and ethylene carbonate is used as the reaction solvent in step 1.

[24] A method for using the compound having a fluorene skeleton according to item 1 above as a raw material for a thermoplastic resin. [Effects of the Invention]

[0017] The fluorene compound of the present invention has a ring-assembly arene ring substituted at the 9-position of the fluorene ring, and also has diaryl groups at the 2- and 7-positions. Furthermore, the compound having the fluorene skeleton has a low content of sulfur-containing impurities, and more preferably a low content of specific metals such as palladium and a low content of bromine-containing impurities. Therefore, thermoplastic resins made from the fluorene compound have excellent optical properties as well as various other properties (heat resistance, transparency, hue, moldability, etc.). Furthermore, the present invention allows efficient production of compounds having a fluorene skeleton with such excellent properties. DETAILED DESCRIPTION OF THE INVENTION

[0018] The present invention will be described in detail below, but the following explanations of the constituent elements are representative examples of embodiments of the present invention and are not intended to limit the scope of the present invention.

[0019] [Compounds with fluorene skeleton] The compound of the present invention is a compound having a fluorene skeleton represented by the following formula (1), i.e., a compound in which two aromatic hydrocarbons having at least one hydroxy group are substituted or added to the 9-position of a fluorene.

[0020] [ka]

[0021] (In the formula, R 1 is a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 12 carbon atoms which may contain an aromatic group; Ar 1 and Ar 2 each independently represents an aromatic group having 6 to 12 carbon atoms which may have a substituent; L 1 is an alkylene group having 1 to 12 carbon atoms, m1 and n1 are the same or different and represent an integer of 0 to 4, m2 and n2 are the same or different and represent an integer of 0 to 3, and m1+m2≧1, provided that m1+n1 is an integer of 4 or less, and m2+n2 is an integer of 3 or less, and o1 and o2 each independently represent an integer of 0 to 5.

[0022] In the above formula (1), specific examples of the naphthalene ring are preferably a 1,4-naphthalenediyl group or a 2,6-naphthalenediyl group, and more preferably a 2,6-naphthalenediyl group.

[0023] The two naphthalene rings substituted at the 9-position of the fluorene ring may be the same or different, and are preferably the same ring. The substituent of the naphthalene ring substituted at the 9-position of the fluorene skeleton is not particularly limited. For example, in the case of a naphthalene ring, the group corresponding to the naphthalene ring substituted at the 9-position of the fluorene ring may be a 1-naphthyl group, a 2-naphthyl group, or the like.

[0024] In the above formula (1), R 1 represents a hydrogen atom, a halogen atom, or a hydrocarbon group which may contain an aromatic group having 1 to 12 carbon atoms, and preferably a hydrogen atom, a methyl group, or a phenyl group.

[0025] In the above formula (1), R 1Examples of the hydrocarbon group represented by the formula (I) include an alkyl group, a cycloalkyl group, an aryl group, a naphthyl group, and an aralkyl group. Specific examples of the alkyl group include C groups such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, and a t-butyl group. 1-6 Alkyl group, C 1-4 Alkyl group, C 1-3 Alkyl groups are preferred, and C 1-3 More preferred are alkyl groups, with methyl or ethyl groups being even more preferred.

[0026] Specific examples of the cycloalkyl group include C cyclopentyl and cyclohexyl groups. 5-8 Cycloalkyl groups, C 5-6 Cycloalkyl groups are preferred, and C 5-6 Cycloalkyl groups are more preferred.

[0027] Specific examples of the aryl group include a phenyl group and an alkylphenyl group (such as a mono- or dimethylphenyl group, a tolyl group, a 2-methylphenyl group, and a xylyl group), and a phenyl group is more preferred.

[0028] Specific examples of the aralkyl group include C aryl groups such as benzyl and phenethyl groups. 6-10 Aryl-C 1-4 Preferred examples include alkyl groups. As the halogen atom, a fluorine atom, a chlorine atom, a bromine atom, etc. are preferred.

[0029] In the above formula (1), the substituent R 1 The substitution numbers n1 and n2 can be appropriately selected depending on the number of fused rings in the fused hydrocarbon, are not particularly limited, and are preferably each independently an integer of 0 or more, more preferably an integer of 1 or more. Note that the substitution numbers n1 and n2 may be the same or different in the naphthalene ring, and are usually often the same.

[0030] In the above formula (1), L 1represents a divalent linking group, and is preferably an alkylene group having 1 to 12 carbon atoms, and more preferably an ethylene group. 1 may be the same alkylene group on the same naphthalene ring. 1 may be the same or different in different naphthalene rings, and usually may be the same.

[0031] Oxyalkylene group (OL 1 The numbers (number of moles added) o1 and o2 can each be selected from the range of 0 to 5, with the lower limit preferably being 0 or more and the upper limit preferably being 4 or less, more preferably 3 or less, and even more preferably 2 or less. 0 or 1 is particularly preferred, and 1 is most preferred. o1 and o2 may be integers or average values, and may be the same or different in different naphthalene rings. It is preferred that m1 is 1 and m2 is 0.

[0032] In the above formula (1), Ar 1 and Ar 2 each independently represents an aromatic group having 6 to 10 carbon atoms, and a phenyl group or a naphthyl group is preferred. 1 and Ar 2 They may be different or the same, but are usually the same. 1 and Ar 2 The bonding positions of each of the above are preferably the 1st and 8th positions, the 2nd and 7th positions, the 3rd and 6th positions, or the 4th and 5th positions of the fluorene skeleton, more preferably the 2nd and 7th positions, the 3rd and 6th positions, or the 4th and 5th positions, and even more preferably the 2nd and 7th positions.

[0033] Representative examples of the diol component represented by the formula (1) are shown below, but the raw materials used in the formula (1) of the present invention are not limited to these.

[0034] Diphenylfluorene types include 9,9-bis(6-hydroxy-2-naphthyl)-1,8-diphenylfluorene, 9,9-bis(6-hydroxy-2-naphthyl)-2,7-diphenylfluorene, 9,9-bis(6-hydroxy-2-naphthyl)-3,6-diphenylfluorene, 9,9-bis(6-hydroxy-2-naphthyl)-4,5-diphenylfluorene, and 9,9-bis[6-(2- Preferred examples thereof include 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-1,8-diphenylfluorene, 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-2,7-diphenylfluorene, 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-3,6-diphenylfluorene, and 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-4,5-diphenylfluorene. Among these, the following formulas (1-a) to (1-b) are more preferred, including the following formula (1-a): 9,9-bis(6-hydroxy-2-naphthyl)-2,7-diphenylfluorene and the following formula (1-b): 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-2,7-diphenylfluorene, and the following formula (1-b): 9,9-bis(4-(2-hydroxyethoxy)phenyl)-2,7-diphenylfluorene is particularly preferred.

[0035] [ka]

[0036] [ka]

[0037] Dinaphthylfluorene types include 9,9-bis(6-hydroxy-2-naphthyl)-1,8-di(1-naphthyl)fluorene, 9,9-bis(6-hydroxy-2-naphthyl)-2,7-di(1-naphthyl)fluorene, 9,9-bis(6-hydroxy-2-naphthyl)-3,6-di(1-naphthyl)fluorene, 9,9-bis(6-hydroxy-2-naphthyl)-4,5-di(1-naphthyl)fluorene, and 9,9-bis(6-hydroxy-2-naphthyl)-4,5-di(1-naphthyl)fluorene. Bis[6-(2-hydroxyethoxy)-2-naphthyl]-1,8-di(1-naphthyl)fluorene, 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-2,7-di(1-naphthyl)fluorene, 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-3,6-di(1-naphthyl)fluorene, 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-4,5-di(1-naphthyl)fluorene fluorene, 9,9-bis(6-hydroxy-2-naphthyl)-1,8-di(2-naphthyl)fluorene, 9,9-bis(6-hydroxy-2-naphthyl)-2,7-di(2-naphthyl)fluorene, 9,9-bis(6-hydroxy-2-naphthyl)-3,6-di(2-naphthyl)fluorene, 9,9-bis(6-hydroxy-2-naphthyl)-4,5-di(2-naphthyl)fluorene, 9,9-bis[6-(2-hydroxyethoxy)ethoxy]fluorene Preferred examples thereof include 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-1,8-di(2-naphthyl)fluorene, 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-2,7-di(2-naphthyl)fluorene, 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-3,6-di(2-naphthyl)fluorene, and 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-4,5-di(2-naphthyl)fluorene. Among these, the following formulas (2-a) to (2-b) are more preferred, including the following formula (2-a): 9,9-bis(6-hydroxy-2-naphthyl)-2,7-di(2-naphthyl)fluorene and the following formula (2-b): 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-2,7-di(2-naphthyl)fluorene, and the following formula (2-b): 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-2,7-di(2-naphthyl)fluorene is particularly preferred.

[0038] [ka]

[0039] [ka]

[0040] In the compound having a fluorene skeleton of the present invention, the content of palladium element preferably satisfies the following formula (2). 0 ≦ Pd ≦ 50 ppm (2) More preferably, the following formula (2-1) is satisfied. 0 ≦ Pd ≦ 25 ppm (2-1) More preferably, the following formula (2-2) is satisfied. 0 ≦ Pd ≦ 10 ppm (2-2) Even more preferably, the following formula (2-3) is satisfied. 0 ≦ Pd ≦ 5 ppm (2-3) It is particularly preferable that the following formula (2-4) is satisfied. 0 ≦ Pd ≦ 3 ppm (2-4)

[0041] If the upper limit of the above range is exceeded, it may have an adverse effect on the color of the resin using the raw material alcohol represented by formula (1) and on the optical components using the resin. The lower limit of the palladium element content may be 0.01 ppm or more, 0.05 ppm or more, or 0.10 ppm or more.

[0042] The compound having a fluorene skeleton of the present invention preferably has an APHA of 500 or less, more preferably 200 or less, and even more preferably 1100 or less, in a 5 wt % solution dissolved in dimethylformamide. If the APHA is greater than 500, it may adversely affect the hue of a resin using the raw material alcohol represented by formula (1) or an optical component using the resin.

[0043] The compound having a fluorene skeleton of the present invention has a sulfur content of 200 ppm or less, preferably 100 ppm or less, more preferably 50 ppm or less, and even more preferably 30 ppm or less. If the sulfur content is greater than 200 ppm, it will adversely affect the color of the resin using the raw material alcohol represented by formula (1) and the optical components using the resin. Furthermore, when using the raw material alcohol represented by formula (1), a reaction failure will occur when obtaining the resin.

[0044] The compound having a fluorene skeleton of the present invention preferably has a bromine content of 150 ppm or less, more preferably 50 ppm or less, and even more preferably 20 ppm or less. If the bromine content is greater than 150 ppm, this may adversely affect the color of the resin produced using the raw material alcohol represented by formula (1) and the optical components produced using the resin. Furthermore, the reaction may be insufficient when the raw material alcohol represented by formula (1) is used to produce the resin.

[0045] Furthermore, in the compound having a fluorene skeleton of the present invention, the content of diphenylfluorenone in the compound represented by formula (1-b) is preferably 0.2% or less, more preferably 0.1% or less, and even more preferably 0.05% or less. If the content of diphenylfluorenone is more than 0.2%, it may have an adverse effect on the color of the resin using the raw material alcohol represented by formula (1) and on the optical components using the resin.

[0046] [Method of producing a compound having a fluorene skeleton] The compound having a fluorene skeleton of the present invention can be produced by the following steps 1 to 3. Step 1: A step of reacting a fluorenone represented by the following formula (3) with an alcohol represented by the following formula (4) in a reaction solvent in the presence of an acid catalyst to obtain a compound represented by the following formula (5): Step 2: A step of reacting a compound represented by the following formula (5) with ethylene carbonate in a reaction solvent in the presence of a base to obtain a compound represented by the following formula (6): Step 3: A step of reacting a compound represented by the following formula (6) with a boronic acid represented by the following formula (7) or (8) in a reaction solvent in the presence of a base and a palladium catalyst to obtain a compound represented by the above formula (1).

[0047] [ka] (In the formula, X 1 is a substituent at the 1st, 2nd, 3rd or 4th position, and X 2 is a substituent at the 5th, 6th, 7th or 8th position and represents a halogen atom.

[0048] [ka] (In the formula, p1 and p2 are the same or different and are integers of 0 to 4; R 1 , n1 and n2 are the same as in formula (1).

[0049] [ka] (In the formula, X 1 and X 2 is the same as the above formula (3). 1 where p1 and p2 are the same as in formula (4), and n1 and n2 are integers from 0 to 3.

[0050] [ka] (In the formula, X 1 and X 2 is the same as the above formula (3). 1 , L 1 , m1, m2, n1, n2, o1 and o2 are the same as in equation (1).

[0051] [ka] [ka] (wherein Y is an aromatic group, R14 represents a hydrogen atom, an alkyl group, an alkenyl group, an alkoxy group, or a halogen atom. l is 0, 1, or 2. When l=2, R 14 may be the same or different.)

[0052] The compound represented by the formula (3) is a fluorenone compound corresponding to the fluorene skeleton in the formula (1), and X 1 is a substituent at the 1st, 2nd, 3rd or 4th position, and X 2 is a substituent at the 5-, 6-, 7- or 8-position, and X 1 and X 2 Both represent a halogen atom.

[0053] Representative examples of the fluorenone compound represented by the above formula (3) are shown below, but the raw materials used in the above formula (1) of the present invention are not limited to these.

[0054] Specific examples include 1,8-difluorofluorenone, 2,7-difluorofluorenone, 3,6-difluorofluorenone, 4,5-difluorofluorenone, 1,8-dichlorofluorenone, 2,7-dichlorofluorenone, 3,6-dichlorofluorenone, 4,5-dichlorofluorenone, 1,8-diiodofluorenone, 2,7-diiodofluorenone, 3,6-diiodofluorenone, 4,5-diiodofluorenone, 1,8-dibromofluorenone, 2,7-dibromofluorenone, 3,6-dibromofluorenone, 4,5-dibromofluorenone, etc. Among these, 1,8-dibromofluorenone, 2,7-dibromofluorenone, 3,6-dibromofluorenone, and 4,5-dibromofluorenone are preferred, with 2,7-dibromofluorenone being particularly preferred. These may be used alone or in combination of two or more, and may be selected arbitrarily depending on the purpose. In the present invention, 2,7-dibromofluorenone is preferred.

[0055] The purity of the fluorenones represented by the formula (3) used is not particularly limited, but is usually preferably 95% or more, more preferably 99% or more. The fluorenones may be commercially available or synthesized. For example, a method for producing dibromofluorenones includes the method described in a non-patent document (Journal of the American Chemical Society, 2017, Vol. 139, 11073-11080), i.e., a method of reacting 9-fluorenone with bromine in water.

[0056] The alcohols represented by the formula (4) correspond to the (poly)hydroxyl group-containing arene ring substituted at the 9-position in the fluorene derivative represented by the formula (3). That is, the naphthalene ring in the formula (4) is the naphthalene ring of the formula (1) with R 1 , n1 and n2 are R in the formula (1) 1 , n1 and n2.

[0057] Specific examples of the compound represented by the formula (4) include naphthols (for example, naphthol (1-naphthol, 2-naphthol), naphthols having a hydrocarbon group (methyl naphthol, ethyl naphthol, dimethyl naphthol, propyl naphthol, butyl naphthol (C 1-4 Alkyl naphthols (such as alkyl naphthols), alkoxy naphthols (such as ethoxy naphthols), 1-4Examples of suitable alcohols include alkoxynaphthols, halonaphthols (chloronaphthols, bromonaphthols), and polyhydroxynaphthalenes corresponding to these naphthols (or monohydroxynaphthalenes) (e.g., di- or trihydroxynaphthalenes such as 1,3-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 1,5-hydroxynaphthalene, 1,7-dihydroxynaphthalene, 1,8-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,2,4-trihydroxynaphthalene, and 1,3,8-trihydroxynaphthalene). Among these, 1-naphthol and 2-naphthol are preferred, with 2-naphthol being particularly preferred. These alcohols may be used alone or in combination and reacted with fluorenones. The alcohols can be selected arbitrarily depending on the purpose. 2-naphthol is preferred in the present invention.

[0058] In the reaction of step 1, the amount of the alcohol represented by the above formula (4) to be used is not particularly limited, but from the viewpoints of suppressing side reactions and economy, it is preferably 2 to 20 moles, more preferably 2.1 to 10 moles, and even more preferably 2.3 to 5 moles per mole of the fluorenone.

[0059] These alcohols represented by the above formula (4) may be commercially available products or synthesized products. For example, a method for producing naphthols includes the method described in a patent document (JP-A-61-115039), in which 2-naphthalenesulfonic acid obtained by sulfonating naphthalene is neutralized with an alkali to obtain sodium 2-naphthalenesulfonate, and the product is then dissolved in an alkali to form an alkali salt, which is then hydrolyzed to produce 2-naphthol.

[0060] The purity of the alcohols represented by the above formula (4) (for example, naphthols) used as raw materials is not particularly limited, but is usually preferably 95% or higher, more preferably 99% or higher.

[0061] The reaction in step 1 can usually be carried out in the presence of an acid catalyst. Examples of the acid catalyst include sulfuric acid, thiolic acid, montmorillonite, and heteropolyacid. Among these, heteropolyacid is particularly preferred because it produces less impurities derived from the acid catalyst and makes it easier to obtain the compound having a fluorene skeleton of the present invention.

[0062] The heteropolyacid preferably used in the present invention is generally a general term for compounds formed by the condensation of two or more different inorganic oxyacids. Various heteropolyacids are possible by combining a central oxyacid with another oxyacid that condenses around it. The elements that make up the central oxyacid in small numbers are called heteroelements, and the elements that form the oxyacids that condense around it are called polyelements. The polyelements may be a single type of element or multiple types of elements.

[0063] The heteroatom of the oxyacid constituting the heteropolyacid is not particularly limited, but examples thereof include copper, beryllium, boron, aluminum, carbon, silicon, germanium, tin, titanium, zirconium, cerium, thorium, nitrogen, phosphorus, arsenic, antimony, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, uranium, selenium, tellurium, manganese, iodine, iron, cobalt, nickel, rhodium, osmium, irodium, and platinum. Phosphorus (phosphate) or silicon (silicic acid) is preferred. The polyatom of the oxyacid constituting the heteropolyacid is not particularly limited, but examples thereof include vanadium, molybdenum, tungsten, niobium, and tantalum. Preferably, at least one element selected from vanadium, molybdenum, and tungsten is preferred.

[0064] The heteropolyacid anion constituting the heteropolyacid skeleton may have a variety of compositions. For example, XM 12 O 40 , XM 12 O 42 , XM 18 O 62 , XM6O 24 The preferred composition of the heteropoly acid anion is XM 12O 40 In each formula, X is a hetero element and M is a poly element. Specific examples of heteropolyacids having these compositions include phosphomolybdic acid, phosphotungstic acid, silicomolybdic acid, silicotungstic acid, and phosphovanadomolybdic acid.

[0065] The heteropolyacid may be a free heteropolyacid, or a salt of the heteropolyacid may be used by substituting some or all of the protons with other cations. Therefore, the heteropolyacid referred to in the present invention also includes salts of these heteropolyacids. Examples of cations that can substitute for protons include ammonium, alkali metals, and alkaline earth metals.

[0066] The heteropolyacid may be an anhydride or may contain water of crystallization, but an anhydride is preferred because it reacts faster and suppresses the generation of by-products. In the case of a compound containing water of crystallization, the same effect as that of an anhydride can be obtained by previously carrying out a dehydration treatment such as drying under reduced pressure or azeotropic dehydration with a solvent. The heteropolyacid may be used in a form supported on a carrier such as activated carbon, alumina, silica-alumina, or diatomaceous earth.

[0067] These heteropolyacids may be used alone or in combination of two or more. If necessary, a catalyst other than the heteropolyacid may be used in combination within the scope of the present invention.

[0068] The amount of heteropolyacid used is not particularly limited, but to obtain a sufficient reaction rate, it is preferably 0.0001 times by weight or more, more preferably 0.001 to 30 times by weight, and even more preferably 0.01 to 5 times by weight relative to the fluorenones.

[0069] When carrying out the present invention, the reaction rate can be improved and the production of impurities can be suppressed by using a compound having a thiol group (hereinafter sometimes abbreviated as SH group) in combination with the heteropolyacid in the reaction of step 1. Examples of thiol compounds that can be used in combination in the present invention include mercaptocarboxylic acids, alkanethiols, and salts thereof.

[0070] Examples of mercaptocarboxylic acids include α-mercaptopropionic acid, β-mercaptopropionic acid, thioacetic acid, thioglycolic acid, thiooxalic acid, mercaptosuccinic acid, and mercaptobenzoic acid. Examples of alkanethiols include C alkanethiols such as methanethiol, ethanethiol, 1-propanethiol, 2-propanethiol, 1-butanethiol, 2-butanethiol, 1-pentanethiol, 2-pentanethiol, 1-hexanethiol, 1-heptanethiol, 2-heptanethiol, 1-octanethiol, 2-octanethiol, 1-nonanethiol, 1-decanethiol, 1-undecanethiol, and 1-dodecanethiol. 1-16 Among these compounds having an SH group, β-mercaptopropionic acid and 1-dodecanethiol are preferred because they are inexpensively available, and 1-dodecanethiol is particularly preferred. Such compounds having an SH group may be used alone or in combination of two or more kinds.

[0071] The method for carrying out the reaction in step 1 is not particularly limited, but typically involves charging the compounds represented by formulas (3) and (4) with a heteropolyacid and / or thiol compound into a reactor and heating and stirring them in air or an inert gas atmosphere such as nitrogen or argon in the presence of an inert solvent, such as an aromatic hydrocarbon such as toluene or xylene, and an ester such as ethyl acetate, γ-butyrolactone, or ethylene carbonate. By carrying out the reaction under dehydration conditions, which remove water from the reaction system, including catalyst-containing water and reaction product water, the reaction proceeds more rapidly than without dehydration, suppresses the formation of by-products, and allows the target product to be obtained in higher yield. The dehydration method is not particularly limited, but examples include dehydration by adding a dehydrating agent, dehydration under reduced pressure, and dehydration by azeotropy with a solvent under atmospheric or reduced pressure.

[0072] The reaction solvent used in step 1 is not particularly limited, and examples thereof include aromatic hydrocarbon solvents such as toluene and xylene, halogenated aromatic hydrocarbon solvents such as chlorobenzene and dichlorobenzene, aliphatic hydrocarbon solvents such as pentane, hexane, and heptane, halogenated aliphatic hydrocarbon solvents such as dichloromethane and 1,2-dichloroethane, aliphatic and cyclic ether solvents such as diethyl ether, di-isopropyl ether, methyl-t-butyl ether, diphenyl ether, tetrahydrofuran, and dioxane, ester solvents such as ethyl acetate, butyl acetate, γ-butyrolactone, and ethylene carbonate, nitrile solvents such as acetonitrile, propionitrile, butyronitrile, and benzonitrile, and amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, and 1-methyl-2-pyrrolidinone. Aromatic hydrocarbon solvents and ester solvents are preferred, and mixed solvents of toluene, xylene, chlorobenzene, or dichlorobenzene with ethyl acetate, butyl acetate, γ-butyrolactone, or ethylene carbonate are more preferred, and mixed solvents of toluene and ethylene carbonate are even more preferred. These reaction solvents may be used alone or in combination of two or more.

[0073] The amount used is not particularly limited, but from the economical point of view, it is preferably 0.1 times by weight or more, more preferably 0.5 to 100 times by weight, and even more preferably 1 to 20 times by weight relative to the amount of fluorenones.

[0074] The reaction temperature in step 1 varies depending on the types of raw materials and solvent used, but is preferably 50 to 300° C., more preferably 80 to 250° C., and even more preferably 100 to 180° C. The reaction can be monitored by an analytical means such as liquid chromatography.

[0075] The internal pressure during the reaction in step 1 is preferably 101.3 kPa or less, more preferably 60.0 kPa or less. It is preferable to carry out the reaction while discharging the by-produced water from the system at this internal pressure, because this allows the reaction to proceed more efficiently and reduces the amount of by-products produced.

[0076] After the reaction in step 1, the solid acid used may be removed by filtration or neutralized, if necessary. Examples of bases used in neutralization include alkali metal or alkaline earth metal hydroxides such as sodium hydroxide, potassium hydroxide, and calcium hydroxide; alkali metal or alkaline earth metal carbonates (bicarbonates) such as potassium carbonate, calcium carbonate, sodium carbonate, and sodium carbonate; and amines. Separation and purification may also be performed by separation means such as filtration, concentration, extraction, crystallization, recrystallization, reprecipitation, activated carbon treatment or similar metal removal treatments, column chromatography, or a combination of these.

[0077] In the reaction of step 1, the reaction solution after neutralization can be used for the reaction with ethylene carbonate without removing the salt generated by neutralization. If necessary, the salt generated by neutralization may be separated from the reaction system by filtration, or by adding water, stirring, allowing to stand, and then separating the solution and removing the aqueous layer (sometimes referred to as a water-washing step). This water-washing step may be carried out repeatedly as necessary.

[0078] After the reaction in step 1, the fluorene compound represented by formula (5) can be reacted with ethylene carbonate without being extracted. That is, steps 1 and 2 can be carried out in one pot. Extracting the fluorene compound represented by formula (5) by methods such as concentration or crystallization may result in a decrease in yield and an increase in costs.

[0079] In step 2, ethylene carbonate is usually used in an amount of 2 to 10 moles, preferably 2 to 8 moles, more preferably 2 to 6 moles, per mole of the fluorenone. In step 2, the reaction between the fluorene compound represented by formula (5) and ethylene carbonate may be carried out in the presence of a basic compound, if necessary. When the reaction is carried out in the presence of a basic compound, it is preferable to separate the solid acid used in step 1 by filtration or neutralize it before carrying out step 2.

[0080] Examples of basic compounds that can be used in step 2 include carbonates, bicarbonates, hydroxides, organic bases, etc. Examples of carbonates include potassium carbonate, sodium carbonate, cesium carbonate, and lithium carbonate. Examples of bicarbonates include potassium bicarbonate, sodium bicarbonate, lithium bicarbonate, and cesium bicarbonate. Examples of hydroxides include sodium hydroxide, potassium hydroxide, and lithium hydroxide. Examples of organic bases include triethylamine, dimethylaminopyridine, triphenylphosphine, tetramethylammonium bromide, and tetramethylammonium chloride. Among the above basic compounds, potassium carbonate and sodium carbonate are preferred from the viewpoints of ease of handling and safety. These basic compounds may be used alone or in combination of two or more. When a basic compound is used in step 2, the amount used is usually 0.01 to 1.0 mol, and preferably 0.03 to 0.5 mol, per 1 mol of the fluorenones.

[0081] After the reaction in step 2 is completed, it is preferable to add an alkaline aqueous solution having a concentration of 3% by weight or more to the resulting reaction mixture and heat and stir at a temperature of 50°C or higher (hereinafter referred to as the alkali purification step). The concentration of the alkaline aqueous solution added to the reaction mixture solution is preferably 3% by weight or more, more preferably 6% by weight or more, and even more preferably 8% by weight or more. By adding an alkaline aqueous solution having a concentration of 3% by weight or more and heating and stirring at a temperature of 50°C or higher, the by-product formed by the reaction of 1 mole of the compound represented by formula (5) with 3 moles or more of ethylene carbonate decomposes to form the compound represented by formula (6). Furthermore, since coloring components can be removed into the alkaline aqueous solution, a highly pure compound represented by formula (6) with little coloring can be obtained. A concentration of the alkaline aqueous solution lower than 3% by weight is not preferable because by-products and coloring components cannot be efficiently removed. The alkaline concentration is not particularly limited as long as it is 3% by weight or more, but from the perspective of alkali solubility and ease of handling, a concentration of 50% by weight or less, more preferably 30% by weight or less, and even more preferably 15% by weight or less is preferred.

[0082] The temperature at which the aqueous alkaline solution is heated and stirred is preferably 50°C or higher, more preferably 60°C or higher, and even more preferably 80°C or higher. The stirring is carried out at a temperature below the boiling point of the solvent used, more preferably 130°C or lower. Temperatures below 50°C are undesirable because by-products cannot be removed or cannot be removed efficiently. Temperatures above 130°C are undesirable because they increase impurities, resulting in a decrease in purity and a deterioration in color. The stirring time is not particularly limited, but is preferably 0.5 to 10 hours, more preferably 1 to 9 hours, and even more preferably 2 to 8 hours.

[0083] The alkali used in the alkaline aqueous solution of the present invention is not particularly limited, but examples include lithium hydroxide, sodium hydroxide, potassium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, calcium hydroxide, barium hydroxide, sodium carbonate, and potassium carbonate. Sodium hydroxide and potassium hydroxide are preferred. The amount of alkali used is not particularly limited, but to efficiently remove by-products and coloring components, it is usually preferably 0.1 to 20 mol, more preferably 0.2 to 10 mol, and even more preferably 0.3 to 5 mol, per mol of the compound represented by formula (6). If the amount of alkali is less than 0.1 mol, by-products may not be efficiently removed. Furthermore, coloring components may not be efficiently removed, which is undesirable. If the amount of alkali is more than 20 mol, purity may decrease and color may worsen, which is undesirable.

[0084] In the present invention, the alkaline purification step may be carried out by adding an alkaline aqueous solution to a reaction mixture solution containing the compound represented by formula (6) and heating and stirring, or by diluting the reaction mixture solution with an organic solvent and then adding an alkaline aqueous solution and heating and stirring. This step is usually carried out after dilution with an organic solvent. The organic solvent used for dilution is not particularly limited, but examples include aromatic hydrocarbons such as benzene, toluene, xylene, and mesitylene; aliphatic hydrocarbons such as pentane, hexane, and heptane; halogenated aromatic hydrocarbons such as chlorobenzene and dichlorobenzene; dimethylformamide; and dimethyl sulfoxide. After the alkaline purification step, the alkaline aqueous solution can be separated and removed.

[0085] After completion of the reaction in step 2, the resulting reaction mixture may be separated and purified by separation means such as washing, filtration, concentration, extraction, crystallization, recrystallization, reprecipitation, activated carbon treatment or similar metal removal treatment, column chromatography, or a combination of these. The operation of precipitating the compound represented by formula (6) from the reaction mixture that has been subjected to the above-mentioned post-treatment, if necessary, is carried out by heating the reaction mixture, optionally mixed with a solvent, to a temperature of 50°C or higher but below the boiling point of the solvent (preferably 70 to 110°C) and cooling it to less than 50°C. If crystals of the compound represented by formula (6) precipitate from the reaction mixture at temperatures above 50°C, the reaction mixture may be mixed with a diluent solvent in an amount such that crystals no longer precipitate at temperatures above 50°C, followed by heating the resulting mixture to a temperature of 50°C or higher but below the boiling point of the solvent (preferably 70 to 110°C) and cooling it to less than 50°C. Examples of the crystallization solvent include those exemplified as the solvent used in the above reaction, alcohol solvents such as methanol, ethanol, propanol, isopropanol, butanol, tert-butanol, isobutanol, and pentanol, carbonate solvents such as dimethyl carbonate and diethyl carbonate, ester solvents such as ethyl acetate, butyl acetate, γ-butyrolactone, butyl benzoate, methyl benzoate, and phenyl acetate, ether solvents such as diethyl ether, di-iso-propyl ether, methyl tert-butyl ether, diphenyl ether, and tetrahydrofuran, and aliphatic hydrocarbon solvents such as hexane, heptane, octane, and pentane, with methanol, ethanol, toluene, or dimethyl carbonate being preferred.

[0086] This crystallization procedure may be carried out once or repeatedly. In particular, when an alcohol such as methanol or ethanol is used, impurities such as unreacted 2-naphthol and by-product ethylene glycol mono(2-naphthyl) ether can be easily and efficiently removed.

[0087] The precipitated crystals are recovered by filtration or the like. The obtained crystals may be washed with the solvent used in the above reaction or may be dried. The purity of the purified product of the compound represented by formula (6) thus obtained is preferably 90% or more, more preferably 95% or more. After the reaction of step 2, step 3 may be carried out in one pot without taking out the compound represented by formula (6). Furthermore, steps 1 to 3 may all be carried out in one pot. By carrying out the reaction in one pot, the yield and productivity can be improved.

[0088] The ring Y of the compound represented by the formula (7) or (8) is a group Ar 1 and Ar 2 In addition, in the formulas (7) and (8), the group R 14 A preferred embodiment of the R 1 The preferred embodiments of n1 and n2 are the same as those of n1 and n2.

[0089] The purity of the boronic acids used is not particularly limited, but is usually preferably 95% or higher, more preferably 99% or higher. The boronic acids may be commercially available or synthesized. Examples of methods for producing boronic acids include the method described in Patent Document (JP-A-2002-47292), i.e., a method of reacting a phenyl Grignard reagent with a boric acid ester dissolved in a non-ether aromatic solvent.

[0090] The boronic acids used in the present invention include alkylboronic acids, alkenylboronic acids, arylboronic acids, heteroarylboronic acids, and anhydrides thereof, which are represented by the formulas (4) and (5). Examples of alkylboronic acids include butylboronic acid, cyclohexylboronic acid, cyclopentylboronic acid, 2-ethylboronic acid, 4-ethylboronic acid, hexylboronic acid, isobutylboronic acid, isopropylboronic acid, methylboronic acid, n-octylboronic acid, propylboronic acid, pentylboronic acid, 2-phenylethylboronic acid, and anhydrides thereof. Rarely, alkenylboronic acids include 1-cyclopentenylboronic acid, ferroceneboronic acid, 1,1'-ferrocenediboronic acid and their anhydrides, while arylboronic acids include 2-anthraceneboronic acid, 9-anthraceneboronic acid, benzylboronic acid, 2-biphenylboronic acid, 3-biphenylboronic acid, 4-biphenylboronic acid, 2,3-dimethylphenylboronic acid, 2,4-dimethylphenylboronic acid, 2,5-dimethylphenylboronic acid, 2,6-dimethylphenylboronic acid, 3,4-dimethylphenylboronic acid, 3,5-Dimethylphenylboronic acid, 2-ethoxyphenylboronic acid, 3-ethoxyphenylboronic acid, 4-ethoxyphenylboronic acid, 6-methoxy-2-naphthaleneboronic acid, 2-methylphenylboronic acid, 3-methylphenylboronic acid, 4-methylphenylboronic acid, 1-naphthaleneboronic acid, 2-naphthaleneboronic acid, 9-phenanthreneboronic acid, 10-phenyl-9-anthraceneboronic acid, phenylboronic acid, phenylethaneboronic acid, 4-phenyl(naphthalen-1-yl)boronic acid, 3-propoxyphenylboronic acid, 3-isopropoxyphenylboronic acid, 4-isopropoxyphenylboronic acid, 4-propylphenylboronic acid, 4-isopropylphenylboronic acid, 10-(naphthalene-1- Examples of heteroarylboronic acids include benzofuran-2-boronic acid, dibenzofuran-4-boronic acid, 5-formyl-2-furanboronic acid, 5-formylthiophene-2-boronic acid, furan-2-boronic acid, furan-3-boronic acid, pyridine-3-boronic acid, pyridine-4-boronic acid, quinoline-2-boronic acid, quinoline-3-boronic acid, quinoline-4-boronic acid, quinoline-5-boronic acid, quinoline-6-boronic acid, quinoline-8-boronic acid, isoquinoline-4-boronic acid, 2-thiopheneboronic acid, 3-thiopheneboronic acid, 5-pyrimidineboronic acid, and anhydrides thereof.

[0091] These may be used alone or in combination, and may be selected arbitrarily depending on the purpose. In the present invention, phenylboronic acid, 2-naphthaleneboronic acid, or anhydride thereof is preferred, and phenylboronic acid or anhydride thereof is particularly preferred.

[0092] The compound represented by formula (7) used as a raw material may be used in an amount of preferably 2 to 5 moles, more preferably 2.05 to 3.0 moles, and even more preferably about 2.1 to 2.5 moles per mole of the compound represented by formula (6). If the amount of the boronic acid is less than 2 moles, the yield of the product represented by formula (6) may be low. If the amount of the boronic acid is more than 5 moles, the reaction rate is high and the yield is high, but the production cost of the compound having a fluorene skeleton may increase.

[0093] The compound represented by formula (8) may be used in an amount of preferably 0.7 to 5 moles, more preferably 0.8 to 3 moles, and even more preferably 1 to 2 moles relative to 1 mole of the compound represented by formula (6). If the amount of the boronic acid is less than 0.7 moles, the yield of the product represented by formula (6) may be low. If the amount is more than 5 moles, the reaction rate is high and the yield is high, but the production cost of the compound having a fluorene skeleton may increase.

[0094] The reaction (dehalogenation reaction) of the compound represented by the formula (6) with the compound represented by the formula (7) and / or (8) in step 3 can be carried out in a reaction solvent in the presence of a base and a catalyst. Examples of bases used in the reaction of step 3 include inorganic salts such as hydroxides (e.g., sodium hydroxide, potassium hydroxide, etc.), carbonates (e.g., sodium carbonate (NaCO), potassium carbonate (KCO), cesium carbonate (CsCO), etc.), acetates (e.g., sodium acetate, potassium acetate, etc.), phosphates (e.g., sodium phosphate (NaPO), potassium phosphate (KPO), etc.), and organic salts (e.g., triethylamines, pyridine, morpholine, quinoline, piperidine, anilines, and ammonium salts (e.g., tetra-n-butylammonium acetate). Among these, carbonates are preferred, with potassium carbonate and / or sodium carbonate being preferred. Such bases may be used alone or in combination of two or more.

[0095] In the reaction of step 3, the amount of the base used is not particularly limited, but is preferably 1 to 30 equivalents, more preferably 1 to 10 equivalents, per mole of boronic acids. The palladium catalyst used in the reaction of Step 3 is preferably a palladium compound used in Suzuki coupling, such as tetrakis(triphenylphosphine)palladium, bis(triphenylphosphine)palladium dichloride, palladium acetate, tris(dibenzylideneacetone)dipalladium, bis(dibenzylideneacetone)palladium, bis[4-(N,N-dimethylamino)phenyl]di-tert-butylphosphinepalladium dichloride, bis(di-tert-butylprenylphosphine)palladium dichloride, bis(di-tert-crotylphosphine)palladium dichloride, or a palladium catalyst represented by Pd / SiO2. Among these, tetrakis(triphenylphosphine)palladium and / or a palladium catalyst represented by Pd / SiO2 are preferred. Such palladium catalysts may be used alone or in combination of two or more.

[0096] In the reaction of step 3, the amount of the catalyst used is not particularly limited, but is preferably 0.1 to 10 mmol, more preferably 0.5 to 5 mmol, in terms of palladium metal atoms, per mole of the compound represented by formula (6). If the amount of the palladium catalyst used is less than 0.1 mmol in terms of palladium metal atoms, the reaction may be difficult to complete. On the other hand, if the amount of the palladium catalyst used exceeds 10 mmol in terms of palladium metal atoms, the reaction may be completed, but it may be difficult to keep the palladium element content in the compound having a fluorene skeleton within the range of formula (2), which may deteriorate the hue of the thermoplastic resin produced using the alcohol raw material, and may also increase the production cost of the compound having a fluorene skeleton.

[0097] The reaction solvent used in step 3 is not particularly limited, and examples thereof include aromatic hydrocarbon solvents such as toluene and xylene, and alcohols such as methanol, ethanol, isopropyl alcohol, and n-butanol, which can be used alone or in combination. Aromatic hydrocarbon solvents have high boiling points, allowing for a high reaction temperature, and alcohols are preferred because they have good affinity with water and improve reactivity. These solvents can be used alone or in combination of two or more. Furthermore, aprotic solvents such as N,N-dimethylformamide and N,N-dimethylacetamide, and halobenzenes such as o-dichlorobenzene can also be used. These solvents can also be used alone or in combination of two or more. In the present invention, a mixed solvent of toluene and ethanol is more preferred.

[0098] The amount of the reaction solvent (in the present invention, a mixed solvent of toluene and ethanol) used is not particularly limited, but is preferably 0.1 times by weight or more, more preferably 0.5 to 100 times by weight, and even more preferably 1 to 50 times by weight, relative to 1 mole of the compound represented by formula (6). If the amount of toluene used is less than 0.1 times by weight, the product may precipitate, making stirring difficult. If the amount of toluene used exceeds 100 times by weight, the effect may not be commensurate with the amount used, the volumetric efficiency may deteriorate, and the production cost of the compound having a fluorene skeleton may increase. The amount of ethanol used is also not particularly limited, but is preferably 0.1 to 50 times by weight, more preferably 1 to 20 times by weight, relative to 1 mole of the compound represented by formula (6). If the amount of ethanol used is less than 0.1 times by weight, the reaction rate may be slow and the yield may decrease. If the amount of ethanol used exceeds 50 times by weight, the effect may not be commensurate with the amount used, the volumetric efficiency may deteriorate, and the production cost of the compound having a fluorene skeleton may increase, as with toluene.

[0099] The reaction temperature varies depending on the raw materials and solvent used, but is preferably 50 to 150° C., more preferably 60 to 130° C., and even more preferably 70 to 120° C. The reaction can be monitored by an analytical means such as liquid chromatography.

[0100] After the reaction is complete, the reaction mixture typically contains unreacted boronic acids, a base, a catalyst, side reaction products, and the like, in addition to the compound represented by formula (1). Therefore, the product can be separated and purified by conventional methods, such as filtration, concentration, extraction, crystallization, recrystallization, reprecipitation, activated carbon treatment or similar metal removal treatments, column chromatography, or a combination of these. For example, it is preferable to remove the boronic acids by conventional methods (such as adding an aqueous alkali solution to form a water-soluble complex), remove the palladium compound by activated carbon treatment or similar metal removal treatments, add a recrystallization solvent, cool, and recrystallize, and then filter and separate the product for purification. The recrystallization method is the same as that described in step 2 above.

[0101] The purity of the compound represented by formula (1) obtained by the production method of the present invention can be selected from a wide range of 60 to 100%, and is preferably 70% or more, more preferably 80% or more, even more preferably 90% or more, and even more preferably 95% or more.

[0102] [Characteristics and uses of compounds with fluorene skeleton] The compounds having a fluorene skeleton of the present invention preferably combine a diphenylfluorene skeleton and a dinaphthylfluorene skeleton with an arene ring, thereby not only exhibiting high refractive index and heat resistance but also reducing birefringence when polymerized. To improve the refractive index, fluorene compounds in which a ring-assembly arene ring is substituted at the 9-position of the fluorene skeleton have been used. However, while this results in high refractive index and heat resistance, it also results in reduced birefringence. In contrast, the compounds having a fluorene skeleton of the present invention, likely due to the presence of a diphenylfluorene skeleton and a dinaphthylfluorene skeleton, exhibit low birefringence despite their high refractive index. Furthermore, the arene ring contains one or more hydroxyl groups, and the fluorene compound as a whole contains multiple hydroxyl groups, resulting in high reactivity. Therefore, the compounds having a fluorene skeleton of the present invention can be used as raw materials (monomers) for various resins. For example, it can be used as a polyol component of thermoplastic resins (e.g., polyester resins, polycarbonate resins, polyester carbonate resins, polyurethane resins, etc.) and thermosetting resins (e.g., epoxy resins, phenolic resins, thermosetting polyurethane resins, (meth)acrylates ((meth)acrylic acid esters), etc.). When the compound having a fluorene skeleton of the present invention is used as a polyol component, the resulting resin has the advantage of being able to achieve both a high refractive index and low birefringence at a high level, probably because a naphthalene ring is substituted at the 9-position of the fluorene skeleton and the fluorene skeleton has a diaryl group.

[0103] Furthermore, the compound having a fluorene skeleton of the present invention can be efficiently used to prepare derivatives in commonly used solvents. The melting point of the compound having a fluorene skeleton of the present invention can be selected from a wide range of 100 to 300°C, and is preferably 120 to 280°C, more preferably 130 to 260°C, and even more preferably 140 to 240°C. [Example]

[0104] The present invention will be described in detail below with reference to examples, but the present invention is not limited to the following examples as long as it does not depart from the gist of the invention. In the examples, various measurements were carried out as follows.

[0105] (1) High-performance liquid chromatograph (HPLC) measurement Measurement was carried out using a Hitachi high performance liquid chromatograph L-2350 under the measurement conditions shown in Table 1. In the examples, unless otherwise specified, % refers to an area percentage value corrected by excluding the solvent in HPLC.

[0106] [Table 1]

[0107] (2)ICP measurement The compounds obtained in the examples were measured using the following apparatus. Equipment used: Agilent Technologies Equipment: Agilent5100 ICP-OES

[0108] (3) Combustion ion chromatography measurement The sulfur content (S amount) and bromine content (Br amount) were measured under the following measurement conditions using a Mitsubishi Chemical AQF-2100 automatic sample combustion apparatus and a Thermo Fisher DIONEX AQUION ion chromatography system. Calibration curves were created using a WAKO bromide ion standard solution (Br-1000) and a sulfate ion standard solution (SO4(2-):1000). Measurement temperature: 900℃→1000℃ Absorbent: Ultrapure water containing hydrogen peroxide Column: AS-17 / AG-17 Flow rate: 1ml / min Cell temperature: 40°C, column temperature: 35°C

[0109] (4)APHA measurement A solution of 0.5 g of the measurement sample dissolved in 10 ml of dimethylformamide was placed in a φ25 mm test tube and measured using a TZ6000 manufactured by Nippon Denshoku Seikogyo Co., Ltd.

[0110] [Example 1] <Step 1 and Step 2> A flask equipped with a stirrer, condenser, and thermometer was charged with 28.1 g (0.08 mol) of 2,7-dibromofluorenone (DBFN), 28.8 g (0.20 mol) of 2-naphthol, 1.8 g (0.01 mol) of n-dodecanethiol, 0.4 g (0.12 mmol) of 12-tungsto(VI) phosphate n-hydrate (H3[PW12O40]·nHO), 30 ml of toluene, and 7.7 g of ethylene carbonate. The pressure was reduced to 50 kPa, and the mixture was heated to 100 °C and stirred at that temperature for 5 hours. The progress of the reaction was monitored by HPLC, and the reaction was terminated when 0.0% DBFN remained.

[0111] After the reaction, 25% by weight aqueous sodium hydroxide solution was added to neutralize the 12-tungsto(VI) phosphate n-hydrate (H3[PW12O40]·nH2O), and the water in the system was distilled off at 120°C. Then, 0.6 g (4.16 mmol) of potassium carbonate, 28.9 g (0.33 mol) of ethylene carbonate, and 100 mL of dimethylformamide were added and stirred at 110°C for 5 hours. The reaction progress was monitored by HPLC, and the reaction was terminated when the remaining amount of 9,9'-bis(6-hydroxy-2-naphthyl)-2,7-dibromofluorene was confirmed to be 0.0%. After the reaction was completed, water and 25% by weight aqueous sodium hydroxide solution were added to the resulting reaction solution, and the mixture was stirred at 85°C for 1.5 hours, after which the aqueous layer was separated. The resulting reaction solution was concentrated, dissolved in toluene, and washed five times with warm water. The crystals were then recrystallized twice from methanol and dried overnight under reduced pressure to obtain white crystals of 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-2,7-dibromofluorene (hereinafter sometimes abbreviated as BNDB) in a yield of 77% and a purity of 97.4%.

[0112] <Process 3> A flask equipped with a stirrer, condenser, water separator, and thermometer was charged with 44.7 g (0.06 mol) of BNDB (prepared in step 1), 17.2 g (0.14 mol) of phenylboronic acid, 0.7 g (0.64 mmol) of tetrakis(triphenylphosphine)palladium, 78 mL of 2 M aqueous potassium carbonate, 292 mL of toluene, and 96 mL of ethanol, followed by stirring at 80 °C for 3 hours. The progress of the reaction was monitored by HPLC, and the reaction was terminated when the remaining amount of BNDB was confirmed to be 0.0%. After the reaction, the precipitated BNDP was collected by filtration, dissolved in tetrahydrofuran, treated with activated carbon, and recrystallized from toluene. The resulting crystals were dried overnight under reduced pressure to obtain white crystals of 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-2,7-diphenylfluorene (hereinafter sometimes abbreviated as BNDP) in 74% yield and 99.2% purity. In addition, APHA was 60, S was 20 ppm, Br was 8 ppm, Pd was 5 ppm, and diphenylfluorenone (hereinafter sometimes abbreviated as DPFN) was 0.0% as measured by HPLC.

[0113] [Example 2] <Process 1~3> A flask equipped with a stirrer, condenser, and thermometer was charged with 28.1 g (0.08 mol) of 2,7-dibromofluorenone (DBFN), 28.8 g (0.20 mol) of 2-naphthol, 0.2 g (0.83 mmol) of n-dodecanethiol, 0.4 g (0.12 mmol) of 12-tungsto(VI) phosphate n-hydrate (H3[PW12O40]·nHO), 30 ml of toluene, and 7.7 g of ethylene carbonate. The pressure was reduced to 50 kPa, and the mixture was heated to 100 °C and stirred at that temperature for 3 hours. The progress of the reaction was monitored by HPLC, and the reaction was terminated when 0.0% DBFN remained.

[0114] After the reaction, 25% by weight aqueous sodium hydroxide solution was added to neutralize the 12-tungsto(VI)phosphate n-hydrate (H3[PW12O40]·nH2O), and the water in the system was distilled off at 120°C. Then, 0.6 g (4.16 mmol) of potassium carbonate, 28.9 g (0.33 mol) of ethylene carbonate, and 100 mL of dimethylformamide were added and stirred at 110°C for 4 hours. The progress of the reaction was monitored by HPLC, and the reaction was terminated when the remaining amount of 9,9'-bis(6-hydroxy-2-naphthyl)-2,7-dibromofluorene was confirmed to be 0.0%.

[0115] After the reaction, 22.3 g (0.18 mol) of phenylboronic acid, 0.5 g (0.42 mmol) of tetrakis(triphenylphosphine)palladium, 91 ml of 2 M aqueous potassium carbonate solution, 170 ml of toluene, and 100 ml of ethanol were added and stirred at 80 °C for 3 hours. The progress of the reaction was monitored by HPLC, and the reaction was terminated when the remaining amount of BNDB was confirmed to be 0.0%. After the reaction, the precipitated BNDP was collected by filtration, dissolved in tetrahydrofuran, treated with activated carbon, and recrystallized from toluene. The resulting crystals were dried overnight under reduced pressure and heated to obtain white crystals of 9,9-bis[6-(2-hydroxyethoxy)-2-naphthyl]-2,7-diphenylfluorene (hereinafter sometimes abbreviated as BNDP) in 75% yield and 99.0% purity. In addition, APHA was 80, S was 8 ppm, Br was 15 ppm, Pd was 3 ppm, and DPFN was 0.0% as measured by HPLC.

[0116] [Comparative Example 1] A fluorenone compound was synthesized in the same manner as in Example 1 except that the reaction solvent was changed to toluene in step 3, but the reaction did not proceed and the target fluorenone compound could not be obtained.

[0117] Comparative Example 2 A fluorene compound was synthesized in the same manner as in Example 1, except that the amount of tetrakis(triphenylphosphine)palladium used in step 3 was changed to 0.56 g (0.48 mmol). Although the reaction proceeded, the diphenyl and monophenyl compounds were mixed in a weight ratio of 95:5, and the target fluorenone compound could not be obtained with high purity.

[0118] Comparative Example 3 A fluorene compound was synthesized in the same manner as in Example 1, except that in step 1, the acid catalyst was changed to sulfuric acid and 3-mercaptopropionic acid. However, the reaction did not proceed, and the target fluorene compound could not be obtained.

[0119] Comparative Example 4 In a flask equipped with a stirrer, condenser, and thermometer, 101.4 g (0.30 mol) of 2,7-dibromofluorenone (hereinafter sometimes abbreviated as DBFN) and 76.8 g (0.63 mmol) of phenylboronic acid were dissolved in a mixed solvent of 1 L of toluene and 200 mL of ethanol. 1.7 g (1.45 mmol) of tetrakis(triphenylphosphine)palladium and 347 mL of 2 M aqueous potassium carbonate solution were added and the mixture was stirred at 80 °C for 6 hours. The progress of the reaction was monitored by HPLC, and the reaction was terminated when the remaining amount of DBFN was confirmed to be 0.1% or less. The resulting reaction solution was concentrated under reduced pressure to remove the toluene and ethanol. The residue was then added with 1 M aqueous sodium hydroxide and extracted with chloroform. The chloroform was concentrated, and when yellow crystals began to precipitate, the concentration was stopped and the mixture was recrystallized. The precipitated yellow solid crystals were collected by filtration and dried at 85°C for 24 hours to obtain 80.5g of the target yellow crystals, 2,7-diphenylfluorenone (hereinafter sometimes abbreviated as DPFN), in a yield of 81%. The purity of the obtained yellow crystals was measured by HPLC and was found to be 99.8%.

[0120] In a flask equipped with a stirrer, a condenser, a water separator, and a thermometer, 56.5 g (0.17 mol) of the DPFN obtained above, 58.8 g (0.41 mol) of 2-naphthol, and 12-tungsto(VI) phosphate monohydrate (H3[PW 12 O 40 After adding 0.8 g (0.24 mmol) of HCl·nH2O, 3.6 g (0.02 mol) of n-dodecanethiol, 53 mL of toluene, and 13 mL of γ-butyrolactone, the pressure was reduced to 55 kPa, the temperature was raised to 100°C, and the mixture was stirred at the same temperature for 10 hours. The progress of the reaction was confirmed by HPLC, and the reaction was terminated when it was confirmed that the remaining amount of DPFN was 0.3% or less.

[0121] After the reaction, 25 wt% aqueous sodium hydroxide solution was added to obtain 12tungsto(VI)phosphate n-hydrate (H3[PW 12 O 40 After neutralizing the 9,9'-bis(6-hydroxy-2-naphthyl)-2,7-diphenylfluorene, the water in the system was distilled off at 120°C (referred to as the water washing step). After the water washing step was completed, 1.2g (8.87mmol) of potassium carbonate and 37.4g (0.42mol) of ethylene carbonate were added and the reaction was carried out with stirring at 110°C for 15 hours. The progress of the reaction was confirmed by HPLC, and the reaction was terminated when it was confirmed that the remaining amount of 9,9'-bis(6-hydroxy-2-naphthyl)-2,7-diphenylfluorene was 0.2% by weight or less.

[0122] After the reaction was complete, water and a 25 wt% aqueous solution of sodium hydroxide were added to the resulting reaction mixture, which was then stirred at 85°C for 5 hours, after which the aqueous layer was separated. The resulting reaction mixture was cooled to 20°C and allowed to crystallize, yielding the target BNDP as a pale yellow solid. The resulting BNDP was washed with water and then dried overnight under reduced pressure to obtain a pale yellow solid with a yield of 78% and a purity of 98.8%. The APHA was over 500, the S content was 235 ppm, the Br content was 170 ppm, the Pd content was 70 ppm, and the DPFN content was 0.2% as measured by HPLC. [Industrial Applicability]

[0123] According to the compound having a fluorene skeleton and the method for producing the compound of the present invention, a resin raw material (monomer) having excellent properties such as a high refractive index, heat resistance, and low birefringence can be efficiently produced, and therefore the compound can be suitably used as a resin raw material (monomer), a reaction component for a derivative, etc.

[0124] Therefore, the compound having a fluorene skeleton of the present invention or its derivative, or a resin made from a compound having a novel fluorene skeleton as a raw material (monomer) can be used for optical components such as films, lenses, prisms, optical disks, transparent conductive substrates, optical cards, sheets, optical fibers, optical films, optical filters, and hard coat films, and is particularly useful for lenses.

Claims

1. A compound having a fluorene skeleton represented by one of the following formulas (1a) to (1d), wherein the content of palladium in the compound having the fluorene skeleton satisfies the following formula (2), the APHA of a 5 wt % solution obtained by dissolving the compound having the fluorene skeleton in dimethylformamide is 500 or less, the content of sulfur in the compound having the fluorene skeleton is 200 ppm or less, and the content of bromine in the compound having the fluorene skeleton is 150 ppm or less. 0.01≦Pd≦50ppm (2) 【Chemistry 1】 【Chemistry 2】 【Chemistry 3】 【Chemistry 4】 (In the formula, R 2 to R 13 each independently represent a hydrogen atom, a halogen atom, or a hydrocarbon group which may contain an aromatic group having 1 to 12 carbon atoms. Ar 1 and Ar 2 each independently represent an aromatic group having 6 to 12 carbon atoms which may have a substituent. L 1 represents an alkylene group having 1 to 12 carbon atoms. o1 represents an integer of 0 to 5.)

2. The compound having a fluorene skeleton according to claim 1, wherein the content of palladium element in the compound having a fluorene skeleton represented by any one of the formulas (1a) to (1d) satisfies the following formula (2-1): 0.05≦Pd≦25ppm (2-1)

3. 3. The compound having a fluorene skeleton according to claim 1, wherein the APHA of a 5% by weight solution of the compound represented by any one of formulas (1a) to (1d) in dimethylformamide is 200 or less.

4. The compound having a fluorene skeleton according to claim 1, wherein the formulas (1a) to (1d) are the formula (1b).

5. Ar in the formulas (1a) to (1d) １ and Ar ２ 5. The compound having a fluorene skeleton according to claim 1, wherein is a phenyl group or a naphthyl group.

6. The compound having a fluorene skeleton according to any one of claims 1 to 5, wherein the formulas (1a) to (1d) are compounds represented by formula (1-b): 【Chemistry 5】

7. The compound according to claim 6, wherein the content of diphenylfluorenone in the compound represented by formula (1-b) is 0.2% or less.

8. 10. A method for using the compound having a fluorene skeleton according to claim 1 as a raw material for a thermoplastic resin.

9. A method for using the compound having a fluorene skeleton according to claim 8, which is a thermoplastic resin for lenses.

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