Method for producing polycyclic aromatic compound

Abstract

To provide a production method that can yield a polycyclic aromatic compound represented by the general formula (3) directly from commonly available compounds.SOLUTION: The foregoing problem can be solved by a production method that includes the step of reacting a silole compound represented by the general formula (1) and a pyrene compound represented by the general formula (2) in the presence of a palladium compound, o- chloranil and silver compound (where R1a and R1b are the same or different to represent a hydrogen atom, C1-4 alkyl group or phenyl group, and R2a and R2b are the same or different to represent a hydrogen atom, halogen atom, alkyl group, aryl group or alkoxy group).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a method for producing a polycyclic aromatic compound. [Background technology]

[0002] General formula (3) below:

[0003] [ka] (In the formula, R 2a and R 2b are the same or different and represent a hydrogen atom, an alkyl group, an aryl group, or an alkoxy group. Although the polycyclic aromatic compound represented by the formula (3) has a highly extended π-conjugated structure, it has a band gap that is not present in graphene. Therefore, it is expected to be applied to organic semiconductor devices and is also known to be useful as an organic electroluminescent device (e.g., Patent Document 1, Non-Patent Document 1).

[0004] In addition to the method described in Non-Patent Document 1, a method for producing the compound of formula (3) that can suppress the generation of a large amount of various impurities produced by the method described in the document is also known, which involves intramolecular cyclization using iron chloride to produce a polycyclic aromatic hydrocarbon (e.g., R 2a and R 2b A method for producing a compound in which R is a hydrogen atom has been proposed (Patent Document 2). [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Synlett, 2016, issue 27, page 2081 [Patent documents]

[0006] [Patent Document 1] JP 2019-4058 A [Patent Document 2] JP 2018-184393 A Summary of the Invention [Problem to be solved by the invention]

[0007] In the production method described in Patent Document 2, the intramolecular cyclization reaction proceeds in a relatively good yield. However, the raw material compounds used in the cyclization reaction are generally not easily available. Even if the raw material compounds are synthesized according to the method described in the document, the compounds cannot be obtained in good yield. In addition, since the intramolecular cyclization reaction uses a large amount of iron chloride, it is difficult to obtain a large amount of the substituent that can be introduced (R 2a and R 2b ) was limited.

[0008] An object of the present invention is to provide a process by which the compound of formula (3) can be directly produced from generally available compounds. [Means for solving the problem]

[0009] As a result of intensive research into solving the above problems, the present inventors have found that the above problems can be solved by a method for producing a compound of formula (3) comprising the steps described below. Specifically, the present invention includes the following inventions.

[0010] [1] In the presence of a palladium compound, o-chloranil and a silver compound, a reaction according to the general formula (1):

[0011] [ka] (In the formula, R 1a and R 1b 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 (2):

[0012] [ka] (In the formula, R 2a and R 2b are the same or different and represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, or an alkoxy group. With a pyrene compound represented by general formula (3):

[0013] [ka] (In the formula, R 2a and R 2b has the same meaning as above) A method for producing a compound represented by the formula:

[0014] [2] The silver compound is silver tetrafluoroborate (AgBF 4 ), silver hexafluorophosphate (AgPF 6 ) and silver hexafluoroantimonate (AgSbF 6 The method according to [1], wherein the compound is at least one selected from the group consisting of:

[0015] [3] Palladium compounds are Pd(OCOCH 3 ) 2 , Pd(OCOCF 3 ) 2、 and Pd(acac) 2 The manufacturing method according to [1] or [2], wherein the compound is at least one selected from the group consisting of: Effect of the Invention

[0016] According to the present invention, the compound of formula (3) can be directly produced from a generally available compound. In particular, the present invention is useful as a method for producing the compound of formula (3) having a substituent to which the method of Patent Document 2 cannot be applied.

[0017] Furthermore, according to the present invention, the compound of formula (3) can be produced even using a relatively inexpensive organic acid salt of palladium, typified by palladium acetate, and the like, so that the compound of formula (3) can be provided at a lower cost. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] 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.

[0019] The substituent R in the silole compound represented by formula (1) (hereinafter, sometimes referred to as the compound of formula (1)) used in the present invention 1a and R 1b 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 (1), a methyl group, an ethyl group, or a phenyl group is preferred, and R 1a and R 1b These silole compounds may be used alone or in combination of two or more kinds, if necessary.

[0020] The substituent R in the pyrene compound represented by formula (2) (hereinafter, sometimes referred to as the compound of formula (2)) used in the present invention 2a and R 2b are the same or different and represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group or an alkoxy group. Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

[0021] The alkyl group may have a branch, and examples thereof include linear alkyl groups having 1 to 10 carbon atoms (particularly 1 to 6), such as methyl, ethyl, n-propyl, n-butyl, and n-pentyl, and branched alkyl groups having 3 to 10 carbon atoms (particularly 3 to 6), such as isopropyl, isobutyl, sec-butyl, and tert-butyl. The alkyl group may have a substituent, and examples of the substituent include the halogen atoms described above, the alkoxy groups described below, and the aryl groups described below. When these substituents are present, the number of the substituents may be, for example, 1 to 5.

[0022] Examples of the aryl group include a phenyl group, a pentalenyl group, an indenyl group, a naphthyl group, an anthracenyl group, and a tetracenyl group. The aryl group may have a substituent, and examples of the substituent include the above-mentioned halogen atom, the above-mentioned alkyl group, and the below-mentioned alkoxy group. When the aryl group has these substituents, the number of the substituents can be, for example, 1 to 5.

[0023] Examples of the alkoxy group include linear alkoxy groups having 1 to 10 carbon atoms (particularly 1 to 6), such as methoxy, ethoxy, n-propyloxy, n-butyloxy, and n-pentyloxy, and branched alkoxy groups having 3 to 10 carbon atoms (particularly 3 to 6), such as isopropyloxy, isobutyloxy, sec-butyloxy, and tert-butyloxy. The alkoxy group may have a substituent, and examples of the substituent include the above-mentioned halogen atoms and the above-mentioned aryl groups. When the alkoxy group has these substituents, the number of the substituents can be, for example, 1 to 5.

[0024] The substituent R in the compound of formula (2) 2a and R 2b Among these, a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms is preferred, and a hydrogen atom or an alkyl group having 1 to 4 carbon atoms is particularly preferred. The compound of formula (2) 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 (1).

[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(OCOCH 3 ) 2 , Pd 2 (dba) 3 , Pd(OCOCF 3 ) 2 , Pd(acac) 2 , PdCl 2 , PdBr 2 , PdI 2 , Pd(NO 3 ) 2 , Pd(CH 3 CN) 4 (SbF 6 ) 2 In addition, acac means acetylacetonate, and dba means dibenzylideneacetone. Among these palladium compounds, Pd(OCOCH 3 ) 2 , Pd(OCOCF 3 ) 2 and Pd(acac) 2 These palladium compounds may be used alone or in combination of two or more kinds, if necessary.

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

[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 (1).

[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); silver nitrate, silver fluoride, silver chloride, silver bromide, silver iodide, silver sulfate, silver oxide, silver sulfide, and silver tetrafluoroborate (AgBF 4 ), silver hexafluorophosphate (AgPF6 ), silver hexafluoroantimonate (AgSbF 6 Among these silver compounds, inorganic silver compounds are preferred, and silver tetrafluoroborate (AgBF 4 ), silver hexafluorophosphate (AgPF 6 ) and silver hexafluoroantimonate (AgSbF 6 ) is more preferable. These silver compounds may be used alone or in combination of two or more as necessary. If a silver compound is not 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, for example, 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 (1).

[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 the reaction is completed, the compound of formula (3) can be isolated by a conventional method such as concentration, crystallization, filtration, drying, etc. If necessary, the compound of formula (3) 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 thereto. In the following examples, the purity is the area percentage value measured by HPLC under the following conditions. The compounds used in each example were commercially available as reagents and were used as they were.

[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] <Example 1> Into a nitrogen-purged four-neck flask equipped with a stirrer and a condenser, the following compound (1-1):

[0036] [ka] 27 g (135 mmol) of a silole compound represented by the following formula (2-1):

[0037] [ka] 10 g (50 mmol) of the pyrene compound represented by the formula 3 )) 2.5g (11mmol), silver hexafluoroantimonate (AgSbF 6 3.8 g (11 mmol) of ethyl acetate, 64 g (260 mol) of o-chloranil, and 267 g of 1,2-dichloroethane were added, and the mixture was heated to 30° C. with stirring under a nitrogen stream, and stirred at 30° C. for 5 hours. 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. The temperature was raised to 80° C. and the mixture was stirred at the same temperature for 0.5 hours, and the crystals were filtered off at the same temperature. The crystals were then dried under reduced pressure and extracted to obtain the compound represented by the following formula (3-1):

[0038] [ka] The compound represented by the formula (12.5 g, apparent yield: 50%, purity: 99%) was obtained.

[0039] <Example 2> Into a nitrogen-purged four-neck flask equipped with a stirrer and a condenser, the following compound (1-1):

[0040] [ka] 14 g (70 mmol) of a silole compound A represented by the following formula (2-2):

[0041] [ka] 10 g (32 mmol) of the pyrene compound represented by the formula 3 )) 1.2g (5.4mmol), silver hexafluoroantimonate (AgSbF 61.9 g (5.4 mmol) of o-chloranil, 34 g (140 mmol) of o-chloranil, and 1,2-dichloroethane (150 g) were added, and the mixture was heated to 30° C. with stirring under a nitrogen stream, and stirred at 30° C. for 24 hours. After that, the reaction mixture was subjected to post-treatment in the same manner as in Example 1 to obtain the compound represented by the following formula (3-2):

[0042] [ka] The compound represented by the formula (9.8 g, apparent yield 51%, purity 98%) was obtained.

[0043] <Comparative Example 1> Silver hexafluoroantimonate (AgSbF 6 The reaction was carried out in the same manner as in Example 1, except that no distillate was used, and the reaction solution was analyzed by LC after 5 hours of reaction, and it was found that the compound of formula (3-1) was hardly produced. The reaction solution was further stirred for 24 hours at 30°C, and analyzed, but it was found that the compound of formula (3-1) was hardly produced.

Claims

1. In the presence of a palladium compound, o-chloranil and a silver compound, a compound represented by the general formula (1): 【Chemical 1】 (In the formula, R １ａ and R １ｂ 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 (2): 【Chemistry 2】 (In the formula, R ２ａ and R ２ｂ are the same or different and represent a hydrogen atom, a halogen atom, an alkyl group, an aryl group, or an alkoxy group. with a pyrene compound represented by general formula (3): 【Chemistry 3】 (In the formula, R ２ａ and R ２ｂ has the same meaning as above) A method for producing a compound represented by the formula:

2. The silver compound is silver tetrafluoroborate (AgBF ４ ), silver hexafluorophosphate (AgPF ６ ) and silver hexafluoroantimonate (AgSbF ６ 2. The method according to claim 1, wherein the compound is at least one selected from the group consisting of:

3. Palladium compounds are Pd(OCOCH ３ ) ２ , Pd(OCOCF ３ ) ２、 and Pd(acac) ２ The method according to claim 1 or 2, wherein the compound is at least one selected from the group consisting of:

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