Boron-containing polycyclic aromatic compound and method for producing compound

Abstract

To provide a boron-containing polycyclic aromatic compound and a method for producing the same.SOLUTION: Provided is a production method that includes the step of reacting a silole compound represented by the formula (2) and a pyrene compound represented by the formula (3) in the presence of a palladium compound, o- chloranil and silver compound, (where R1a-R1d are the same or different to represent a C1-8 alkyl group, C3-8 cycloalkyl group, phenyl group or C7-11 aralkyl group; R1a and R1b may be combined to form a ring; R1c and R1d may be combined to form a ring; R3a and R3b are the same or different to represent H or an alkyl group).SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a boron-containing polycyclic aromatic compound and a method for producing the same. [Background technology]

[0002] Equation (4) below:

[0003] [ka] Although the polycyclic aromatic compound represented by the formula (4) has a highly extended π-conjugated structure, it has a band gap that graphene does not have, and is therefore expected to be applied to organic semiconductor devices and is also known to be useful as an organic electroluminescence device. As a method for producing such a compound of the formula (4), for example, the method described in Patent Document 1 has been proposed. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2018-184393 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, the production method described in Patent Document 1 is a method for producing a compound of formula (4) by an intramolecular cyclization reaction using a large amount of iron chloride. When attempting to produce a polycyclic aromatic compound having a structure in which a substituent has been introduced into the compound of formula (4) by this method, the substituent that can be introduced may be limited, and it may be difficult to apply the method as a production method for a polycyclic aromatic compound having, for example, a boron-containing functional group.

[0006] An object of the present invention is to provide a polycyclic aromatic compound having a structure in which a boron-containing functional group is introduced into the compound of formula (4) in order to further develop the polycyclic aromatic compounds. [Means for solving the problem]

[0007] As a result of intensive research by the present inventors to solve the above problems, it has been found that the above problems can be solved by a production method including the steps described below.

[0008] [1] General formula (1) below:

[0009] [ka] (In the formula, R 1a ~R 1d are the same or different and each represents an optionally substituted alkyl group having 1 to 8 carbon atoms, an optionally substituted cycloalkyl group having 3 to 8 carbon atoms, an optionally substituted phenyl group, or an optionally substituted aralkyl group having 7 to 11 carbon atoms. 1a and R 1b may be joined together to form a ring, R 1c and R 1d may be joined together to form a ring.) A compound represented by the formula:

[0010] [2] General formula (1-1) below:

[0011] [ka] (In the formula, R 2a ~R 2h and are the same or different and each represents an alkyl group having 1 to 6 carbon atoms.

[0012] [3] In the presence of a palladium compound, o-chloranil and a silver compound, a reaction is carried out according to the following general formula (2):

[0013] [ka] (In the formula, R 3a and R 3b are the same or different and represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group. and a silole compound represented by general formula (3):

[0014] [ka] (In the formula, R 1a ~R 1d is as above) A method for producing the compound according to [1] or [2], comprising reacting a pyrene compound represented by the following formula (1): Effect of the Invention

[0015] According to the present invention, it is possible to provide a boron-containing polycyclic aromatic compound represented by the above general formula (1). This compound can be subjected to, for example, a hydroboration reaction to introduce a hydroxyl group, and can also be subjected to a Suzuki-Miyaura coupling reaction to produce derivatives having various aryl groups, alkyl groups, etc., and is therefore extremely useful as a core raw material for further application development of polycyclic aromatic compounds. [Brief description of the drawings]

[0016] [Figure 1] 1 is a mass spectrometry chart of the compound represented by the following formula (1-A), obtained in Example 1, among the compounds represented by the above general formula (1). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] In the present invention, when a range is expressed as "A to B", it means A or more and B or less, unless otherwise specified.

[0018] <Boron-containing polycyclic aromatic compound of the present invention> The boron-containing polycyclic aromatic compound of the present invention is a compound represented by the above general formula (1) (hereinafter, sometimes referred to as a compound of formula (1)).1a ~R 1d In the above, the alkyl group having 1 to 8 carbon atoms, which may have a substituent, may have a branched chain, and specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isoamyl group, a neopentyl group, a 1-ethylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, an n-hexyl group, an isohexyl group, an n-heptyl group, a 1-methylhexyl group, and an n-octyl group. These alkyl groups may be substituted with one or more halogen atoms, alkylthio groups, alkoxy groups, and the like. Examples of the cycloalkyl group having 3 to 8 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, and a cyclooctyl group. These cycloalkyl groups may be substituted with one or more alkyl groups having 1 to 4 carbon atoms. Examples of the aralkyl group having 7 to 11 carbon atoms include a benzyl group, a 1-phenylethyl group, and a 1-phenylpropyl group. These aralkyl groups may be substituted on the aromatic ring with one or more alkyl groups having 1 to 8 carbon atoms, alkoxy groups having 1 to 6 carbon atoms, etc. 1a and R 1b may be joined together to form a ring, and R 1c and R 1d may combine together to form a ring, and may constitute a compound represented by the above general formula (1-1) (hereinafter, sometimes referred to as a compound of formula (1-1)).

[0019] In the above general formula (1-1), R 2a ~R 2h The alkyl group having 1 to 6 carbon atoms represented by the formula (I) may have a branch, and specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isoamyl group, a neopentyl group, a 1-ethylpropyl group, a 1-methylbutyl group, a 2-methylbutyl group, an n-hexyl group, an isohexyl group, etc. Among these alkyl groups having 1 to 6 carbon atoms, an alkyl group having 1 to 4 carbon atoms which may have a branch is preferred.

[0020] <Method for producing boron-containing polycyclic aromatic compound of the present invention> The compound of formula (1) of the present invention can be produced by a method including a step of reacting a silole compound represented by the above general formula (2) (hereinafter, sometimes referred to as the compound of formula (2)) with a pyrene compound represented by the above general formula (3) (hereinafter, sometimes referred to as the compound of formula (3)) in the presence of a palladium compound, o-chloranil and a silver compound.

[0021] The substituent R in the above general formula (2) 3a and R 3b are the same or different and represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group. The alkyl group having 1 to 4 carbon atoms may be branched, and specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butyl group. Among these substituents, from the viewpoint of ease of production of the compound of formula (2), a methyl group, an ethyl group, or a phenyl group is preferred, and R 3a and R 3b These silole compounds may be used alone or in combination of two or more kinds, if necessary.

[0022] The substituent R in the above general formula (3) 1a ~R 1d Specific embodiments of are as described above. 1a and R 1b , R 1c and R 1d are linked together to form a ring, and have the following general formula (3-1):

[0023] [ka] (In the formula, R 2a ~R 2h is as mentioned above.) The compound may be represented by the following formula:

[0024] The compound of formula (3) is usually used in an amount of 0.1 to 0.6 mol, preferably 0.3 to 0.5 mol, per mol of the compound of formula (2).

[0025] As the palladium compound used in the present invention, various palladium compounds known as catalysts for organic synthesis can be used. Examples of palladium compounds that can be used include Pd(OH)2, Pd(OCOCH3)2, Pd2(dba)3, Pd(OCOCF3)2, Pd(acac)2, PdCl2, PdBr2, PdI2, Pd(NO3)2, and Pd(CH3CN)4(SbF6)2. Note that acac means acetylacetonate, and dba means dibenzylideneacetone. Among these palladium compounds, Pd(OCOCH3)2, Pd(OCOCF3)2, and Pd(acac)2 are preferred. These palladium compounds may be used alone or in combination of two or more kinds as necessary.

[0026] The amount of the palladium compound used is usually 0.01 to 0.5 mol, preferably 0.01 to 0.2 mol, per 1 mol of the compound of the formula (2).

[0027] In the present invention, the amount of o-chloranil used is usually 1 to 5 moles, preferably 1.5 to 3 moles, per mole of the compound of the formula (2).

[0028] Examples of the silver compound used in the present invention include organic silver compounds such as silver acetate, silver pivalate (AgOPiv), silver trifluoromethanesulfonate (AgOTf), and silver benzoate (AgOCOPh); inorganic silver compounds such as silver nitrate, silver fluoride, silver chloride, silver bromide, silver iodide, silver sulfate, silver oxide, silver sulfide, silver tetrafluoroborate (AgBF4), silver hexafluorophosphate (AgPF6), and silver hexafluoroantimonate (AgSbF6). Among these silver compounds, inorganic silver compounds are preferred, and silver tetrafluoroborate (AgBF4), silver hexafluorophosphate (AgPF6), and silver hexafluoroantimonate (AgSbF6), etc., are more preferred. These silver compounds may be used alone or in combination of two or more as necessary. If no silver compound is used, the reaction does not proceed, or even if it proceeds, the reaction rate is very slow.

[0029] The amount of the silver compound used is usually 0.1 to 3.0 mol, preferably 0.2 to 1.5 mol, and more preferably 0.5 to 1.2 mol, per mol of the palladium compound.

[0030] The present invention can be carried out in a solvent as necessary. Examples of solvents that can be used include aliphatic hydrocarbons, halogenated aliphatic hydrocarbons, and halogenated aromatic hydrocarbons. Examples of aliphatic hydrocarbons include pentane, hexane, heptane, and cyclohexane. Examples of halogenated aliphatic hydrocarbons include dichloromethane, dichloroethane, chloroform, carbon tetrachloride, and trichloroethylene. Examples of halogenated aromatic hydrocarbons include monochlorobenzene, dichlorobenzene, bromobenzene, and 1,3,5-tribromobenzene. These solvents may be used alone or in combination of two or more as necessary. Among these solvents, halogenated aliphatic hydrocarbons or halogenated aromatic hydrocarbons are preferred. When a solvent is used, the amount of the solvent is, for example, 1.0 to 20 parts by mass, preferably 5.0 to 15 parts by mass, per part by mass of the compound of formula (2).

[0031] The temperature at which the present invention is carried out is, for example, 10 to 150° C., and preferably 20 to 100° C. Furthermore, the present invention may be carried out under at least any one of anhydrous conditions and an inert gas (nitrogen gas, argon gas, etc.) atmosphere.

[0032] After completion of the reaction, the compound of formula (1) can be isolated by a conventional method such as concentration, crystallization, filtration, drying, etc. If necessary, the compound of formula (1) obtained may be purified by a conventional purification procedure such as adsorption, steam distillation, recrystallization, etc. EXAMPLES

[0033] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these. In the following examples, the purity is an area percentage value measured by HPLC under the following conditions.

[0034] [1] UPLC measurement Equipment: Waters Acquity UPLC H-Class Column: ACQUITY UPLC(R) BEH C18 1.7μm (2.1×100mm Column) Column temperature: 45 °C Detection wavelength: UV 254nm Mobile phase: A solution = ultrapure water, B solution = acetonitrile (The concentration of B solution was changed as shown below.) B liquid concentration: 90%→3min→100%(15min hold) ·Mobile phase flow rate: 0.4ml / min Sample injection volume: 1.0μL

[0035] [2] NMR measurement 1 H-NMR and 13 C-NMR was performed using tetramethylsilane as an internal standard and deuterated chloroform (CDCl3) as a solvent on a JEOL-ESC400 ( 1 H 400MHz, 13The data was recorded using a C 100 MHz spectrometer. Each data item was recorded as follows:

[0036] Chemical shift, multiplicity (s=singlet, m=multiplet) and integration.

[0037] [3] LC-MS measurement The target substance was identified by separation and mass spectrometry using LC-MS under the following measurement conditions.

[0038] Equipment: Waters AcquityUPLC H-Class PLUS+PDA / SQD2 system Column: ACQUITY UPLC(R) BEH C18 1.7μm (2.1×100mm Column) Column temperature: 45℃ Detection wavelength: UV 254nm Mobile phase: Solution A = 10 mM ammonium acetate aqueous solution, Solution B = acetonitrile (The concentration of Solution B was changed as shown below.) B liquid concentration: 90%→3min→100%(15min hold) ·Mobile phase flow rate: 0.4ml / min Detection method: Q-MS Ionization method: APCI(+) method Ion Source: Voltage (+) 30V, Temperature 150℃ APCI probe Temp: 500℃ Corona (μA): 0.7μA Desolvation Gas: Temperature 350℃, Gas flow 350L / h

[0039] <Example 1> Among the compounds represented by general formula (1), the compound represented by the following formula (1-A):

[0040] [ka] A production example of a compound represented by the following formula:

[0041] Into a nitrogen-purged four-neck flask equipped with a stirrer and a condenser, was added the following compound (2-A):

[0042] [ka] 12.5 g (57.2 mmol) of a silole compound represented by the following formula (3-A):

[0043] [ka] A mixture of 10 g (22.0 mmol) of a pyrene compound represented by the following formula (I), 1.09 g (4.84 mmol) of palladium acetate (Pd(OCOCH3)), 1.66 g (4.84 mmol) of silver hexafluoroantimonate (AgSbF6), 28.2 g (114.5 mmol) of o-chloranil, and 234 g of 1,2-dichloroethane was added and heated to 30°C with stirring under a nitrogen stream, and then stirred at 30°C for 1 hour. After stirring, the reaction solution was filtered to remove insoluble matter, then concentrated under reduced pressure to remove 1,2-dichloroethane, and 100 g of heptane was added to the flask, heated to 80°C and stirred at the same temperature for 0.5 hours, then cooled to 25°C and filtered to separate the crystals. The crystals were then dried under reduced pressure and extracted to obtain 8.3 g of the compound represented by the above formula (1-A) (50% apparent yield, 87% purity). The LC-MS chart of the obtained compound represented by formula (1-A) is shown in Figure 1. The spectral values ​​are also shown below.

[0044] 1 H-NMR (CDCl3, 400MHz): δ=1.41ppm(12H,s), 7.74-7.77ppm(4H,m), 8.77-8.80ppm(2H,m), 8.92-8.94ppm(2H,m), 9.41ppm(2H,s)

[0045] 13 C-NMR (CDCl3, 100MHz): δ=24.99ppm(C8), 84.13ppm(C4), 123.59ppm(C4), 126.28ppm(C2), 126.69ppm(C4), 126.77ppm(C4), 127.21 ppm(C2), 128.03ppm(C4), 128.95ppm(C4), 129.00ppm(C4), 129.69ppm(C4), 131.16ppm(C4), 132.19ppm(C4)

[0046] Mass spectrometry value ([M+H] + ):755.34 (Calculated molecular weight (QMS APCI + ;[C52H44B2O4+H] + ):755.41)

Claims

1. General formula (1) below: 【Chemistry 1】 (In the formula, R １ａ ~R １ｄ are the same or different and each represents an optionally substituted alkyl group having 1 to 8 carbon atoms, an optionally substituted cycloalkyl group having 3 to 8 carbon atoms, an optionally substituted phenyl group, or an optionally substituted aralkyl group having 7 to 11 carbon atoms. １ａ and R １ｂ may be joined together to form a ring, R １ｃ and R １ｄ may be joined together to form a ring.) A compound represented by the formula:

2. General formula (1-1) below: 【Chemistry 2】 (In the formula, R ２ａ ~R ２ｈ and each may be the same or different and represent an alkyl group having 1 to 6 carbon atoms.

3. In the presence of a palladium compound, o-chloranil and a silver compound, a reaction is carried out according to the following general formula (2): 【Chemistry 3】 (In the formula, R ３ａ and R ３ｂ are the same or different and represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group. and a silole compound represented by general formula (3): 【Chemistry 4】 (In the formula, R １ａ ~R １ｄ is as above) A method for producing the compound according to claim 1 or 2, comprising reacting a pyrene compound represented by the following formula (I):

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