Method for producing amine containing aromatic ring

Abstract

The present invention provides a method for producing an amine containing an aromatic ring with a high yield, the method generating fewer by-products. The present invention provides a method for producing an amine containing an aromatic ring, the method comprising a process in which an amination reaction is caused to proceed by supplying a hydrogen source and a nitrogen source to an acetal compound containing an aromatic ring.

Description

Method for producing aromatic ring-containing amines

[0001] The present invention relates to a method for producing amines containing an aromatic ring.

[0002] Methods for producing amines containing aromatic rings have been studied. For example, Non-Patent Document 1 describes the production of amines containing aromatic rings by the following reaction:

[0003] J. Org. Chem. 2011, 76, 704-707

[0004] The method for producing an amine containing an aromatic ring described in Non-Patent Document 1 has various problems when applied to industrial production. For example, the method for producing an amine described in Non-Patent Document 1 produces a large amount of by-products. Therefore, a new method for producing an amine containing an aromatic ring is desired. In particular, a method for producing an amine containing an aromatic ring with a high yield and a small amount of by-products is desired. The present invention aims to solve these problems and to provide a method for producing an amine containing an aromatic ring with a high yield and a small amount of by-products.

[0005] In light of the above-mentioned problems, the present inventors have conducted research and found that the above-mentioned problems can be solved by using an acetal compound containing an aromatic ring as a raw material and carrying out an amination reaction. Specifically, the above-mentioned problems have been solved by the following means. <1> A method for producing an amine containing an aromatic ring, comprising supplying a hydrogen source and a nitrogen source to an acetal compound containing an aromatic ring to carry out an amination reaction. <2> The method according to <1>, in which the hydrogen source is hydrogen. <3> The method according to <1> or <2>, in which the amination reaction is carried out in the presence of a metal catalyst. <4> The method according to any one of <1> to <3>, in which the acetal compound containing an aromatic ring contains an aromatic heterocycle. <5> The method according to any one of <1> to <3>, in which the acetal compound containing an aromatic ring contains a furan ring. <6> The method according to any one of <1> to <5>, in which the acetal compound containing an aromatic ring contains 1 to 3 acetal groups per molecule. <7> The method according to any one of <1> to <3>, wherein the acetal compound containing an aromatic ring is represented by the following formula (S1): (In formula (S1), X is a heteroatom, and R ｓ１ is —COOH or a hydrocarbon group having 1 to 10 carbon atoms, and R ｓ２ and R ｓ３ are each independently a hydrocarbon group having 1 to 10 carbon atoms, and R ｓ２ and R ｓ３ may be bonded to each other to form a ring. ms is an integer of 0 to 2, and ns is 1 or 2. When ms is 2, each R ｓ１ may be the same or different. When ns is 2, the respective acetal groups may be the same or different.) <8> The production method according to any one of <1> to <3>, wherein the acetal compound containing an aromatic ring is represented by the following formula (S2): (In formula (S2), R ｓ２ and R ｓ３ are each independently a hydrocarbon group having 1 to 10 carbon atoms, and R ｓ２ and R ｓ３may be bonded to each other to form a ring. ms2 is 0 or 1, and ns is 1 or 2. When ns is 2, the acetal groups may be the same or different.) <9> The production method according to any one of <1> to <8>, wherein the nitrogen source contains ammonia and / or an ammonium salt. <10> The production method according to any one of <1> to <8>, wherein the nitrogen source contains an ammonium salt of an organic acid. <11> The production method according to any one of <1> to <10>, wherein the amination reaction is carried out in the presence of a solvent. <12> The solvent is a solvent containing A-(OH) ｍ (wherein A is a hydrocarbon group having 1 to 10 carbon atoms, and m is 1 or 2). ｍ The volume ratio of the compound represented by A-(OH) ｍ <14> The method according to <12>, wherein the amount of water is 0 or more and less than 1 relative to 1 of the compound represented by A-(OH). ｍ The volume ratio of the compound represented by A-(OH) ｍ <15> The method according to <12>, wherein the amount of water is more than 0 and less than 1 relative to 1 of the compound represented by the formula: ｍ <16> The method according to any one of <11> to <15>, wherein the compound represented by the formula (I) contains methanol. <17> The method according to any one of <1> to <13> and <15>, wherein water is not supplied to the reaction system of the amination reaction. <18> The method according to any one of <1> to <17>, wherein the compound represented by the formula (I) contains methanol.

[0006] According to the present invention, it is possible to provide a method for producing an amine containing an aromatic ring in high yield with a small amount of by-products produced.

[0007] Hereinafter, a mode for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. Note that the following present embodiment is an example for explaining the present invention, and the present invention is not limited to this embodiment. Note that in this specification, the term "to" is used to mean that the numerical values ​​written before and after it are included as lower and upper limits. In this specification, various physical property values ​​and characteristic values ​​are those at 23°C unless otherwise specified. In the notation of groups (atomic groups) in this specification, notations that do not indicate substituted or unsubstituted include groups (atomic groups) that do not have a substituent as well as groups (atomic groups) that have a substituent. For example, "alkyl group" includes not only alkyl groups that do not have a substituent (unsubstituted alkyl groups), but also alkyl groups that have a substituent (substituted alkyl groups). In this specification, when not indicating substituted or unsubstituted, unsubstituted is preferred. If the measurement methods, etc. described in the standards shown in this specification vary depending on the fiscal year, they will be based on the standards as of January 1, 2021, unless otherwise specified.

[0008] The method for producing an aromatic ring-containing amine according to the present embodiment includes supplying a hydrogen source and a nitrogen source to an aromatic ring-containing acetal compound to cause an amination reaction. By employing such a production method, it is possible to provide a method for producing an aromatic ring-containing amine with a high yield and with a small amount of by-products.

[0009] In this embodiment, an acetal compound containing an aromatic ring is a compound that serves as the starting material for the reaction in this embodiment. Typically, an acetal compound containing an aromatic ring is introduced into the reaction system, but it may also be an intermediate produced from another compound as a starting material. By using an acetal compound as a starting material, the amination reaction proceeds quickly, and an amine compound containing an aromatic ring is obtained with few by-products. This is presumably because, when an aldehyde compound, which is a precursor of the acetal compound, is used as a starting material, a side reaction occurs in which a formyl group reacts with the resulting amine compound, whereas when an acetal compound is used as a starting material, this side reaction does not occur.

[0010] Acetal is (R １ O-) (R ２O-)R ３ C- (hereinafter referred to as "acetal group"), where R １ and R ２ are each independently a substituent (usually a hydrocarbon group, preferably a hydrocarbon group having 1 to 10 carbon atoms), and R ３ is a hydrogen atom or a substituent (preferably a hydrogen atom). １ and R ２ may be bonded to each other to form a ring, but preferably do not form a ring. Not forming a ring tends to facilitate the amination reaction. In this embodiment, the acetal compound containing an aromatic ring preferably contains 1 to 3 acetal groups per molecule. The acetal compound containing an aromatic ring used in this embodiment preferably has an acetal group directly bonded to the aromatic ring. "An acetal group directly bonded to the aromatic ring" means that the acetal group is bonded to an atom (e.g., a carbon atom) constituting the aromatic ring. The acetal compound used in this embodiment has a different stability of the reaction transition state from conventional compounds due to the inclusion of an aromatic ring. One example of the number of acetal groups per molecule of the acetal compound containing an aromatic ring is 1. Another example of the number of acetal groups per molecule of the acetal compound containing an aromatic ring is 2.

[0011] The aromatic ring contained in the aromatic ring-containing acetal compound is preferably an aromatic ring having 3 to 14 carbon atoms. The aromatic ring may be either an aromatic hydrocarbon ring or an aromatic heterocycle, and is preferably an aromatic heterocycle. The aromatic ring is preferably a 5- or 6-membered ring, and more preferably a 5-membered ring. The aromatic ring may be a monocycle or a fused ring, but is preferably a monocycle. In the case of a fused ring, it is preferably formed by condensing two to four rings, more preferably by condensing two or three rings, and even more preferably by condensing two rings. Specifically, the aromatic hydrocarbon ring is preferably a benzene ring, a naphthalene ring, or an anthracene ring, and the aromatic heterocycle is exemplified by a furan ring, a thiophene ring, a pyrrole ring, a pyrazole ring, an imidazole ring, an oxazole ring, a thiazole ring, a pyridine ring, a pyrimidine ring, a pyran ring, etc., and a furan ring is preferred.

[0012] The molecular weight of the acetal compound containing an aromatic ring is preferably 140 or more, more preferably 180 or more, and is preferably 1,000 or less, more preferably 800 or less.

[0013] The acetal compound containing an aromatic ring is preferably represented by the following formula (S): (In formula (S), Ar is a group containing an aromatic ring having 4 to 10 carbon atoms, and R ｓ１ is —COOH or a hydrocarbon group having 1 to 10 carbon atoms, and R ｓ２ and R ｓ３ are each independently a hydrocarbon group having 1 to 10 carbon atoms, and R ｓ２ and R ｓ３ may be bonded to each other to form a ring. m is an integer of 0 to 9, and n is an integer of 1 to 3. When m is 2 or more, each R ｓ１ may be the same or different. When n is 2 or more, the respective acetal groups may be the same or different.

[0014] Ar is a group containing an aromatic ring having 4 to 10 carbon atoms, and is preferably a 5-membered heterocyclic group, a 6-membered heterocyclic group, a benzene ring group, a biphenyl group, or a naphthyl group. ｓ１ is —COOH or a hydrocarbon group having 1 to 10 carbon atoms, preferably —COOH or a hydrocarbon group having 1 to 8 carbon atoms, more preferably —COOH or an alkyl group having 1 to 5 carbon atoms, and even more preferably —COOH. ｓ２ and R ｓ３ are each independently a hydrocarbon group having 1 to 10 carbon atoms, more preferably a hydrocarbon group having 1 to 5 carbon atoms, and even more preferably a hydrocarbon group having 1 to 3 carbon atoms. ｓ２ and R ｓ３ is preferably an alkyl group, more preferably a methyl group, an ethyl group or a propyl group, and even more preferably a methyl group. ｓ２ and R ｓ３ may be bonded to each other to form a ring. When forming a ring, R ｓ２ and Rｓ３ The total number of carbon atoms in R is preferably 2 to 8. ｓ２ and R ｓ３ It is preferable that m does not form a ring. m is an integer of 0 to 9, preferably 0 to 3, and particularly preferably 0 or 1. n is preferably 1 or 2, and more preferably 1.

[0015] The acetal compound containing an aromatic ring is more preferably represented by the following formula (S1): (In formula (S1), X is a heteroatom, and R ｓ１ is —COOH or a hydrocarbon group having 1 to 10 carbon atoms, and R ｓ２ and R ｓ３ are each independently a hydrocarbon group having 1 to 10 carbon atoms, and R ｓ２ and R ｓ３ may be bonded to each other to form a ring. ms is an integer of 0 to 2, and ns is 1 or 2. When ms is 2, each R ｓ１ may be the same or different. When ns is 2, each acetal group may be the same or different.

[0016] In formula (S1), X is preferably a nitrogen atom, an oxygen atom, or a sulfur atom, and more preferably an oxygen atom. ｓ１ , R ｓ２ , R ｓ３ is R in formula (S) ｓ１ , R ｓ２ , R ｓ３ In one example of this embodiment, ms is 0 and ns is 2. In another example of this embodiment, ms is 1 and ns is 1. In another example of this embodiment, in the heterocycle of formula (S1), R ｓ１ means that an acetal group is bonded to at least one of the 2-, 3-, 4-, and 5-positions, and R ｓ１ is preferably bonded to the 5-position and the acetal group is preferably bonded to the 2-position. ｓ１is absent, and two acetal groups are attached at the 2- and 5-positions.

[0017] Formula (S1) is preferably represented by formula (S2). (In formula (S2), R ｓ２ and R ｓ３ are each independently a hydrocarbon group having 1 to 10 carbon atoms, and R ｓ２ and R ｓ３ may be bonded to each other to form a ring. ms2 is 0 or 1, and ns is 1 or 2. When ns is 2, the acetal groups may be the same or different. In formula (S2), R ｓ２ and R ｓ３ is R in formula (S1) ｓ２ and R ｓ３ In one example of this embodiment, ms2 is 0 and ns is 2. In another example of this embodiment, ms2 is 1 and ns is 1.

[0018] Examples of the acetal compound containing an aromatic ring used in this embodiment are shown below, but the present invention is not limited to these.

[0019] The above compounds are commercially available from a number of manufacturers, and can be obtained from, for example, Tokyo Chemical Industry Co., Ltd.

[0020] The aromatic ring-containing amine obtained by the present embodiment is a compound in which the acetal group in the aromatic ring-containing acetal compound used as a raw material is aminated. The aromatic ring-containing amine obtained by the production method of the present embodiment is preferably represented by the following formula (S-1):

[0021] (In formula (S-1), Ar is a group containing an aromatic ring having 4 to 10 carbon atoms, and R ｓ１is —COOH or a hydrocarbon group having 1 to 10 carbon atoms, m is an integer of 0 to 9, and n is an integer of 1 to 3. When m is 2 or more, each R ｓ１ may be the same or different. When n is 2 or more, the acetal groups may be the same or different. ｓ１ , Ar, m and n are R in formula (S), respectively. ｓ１ , Ar, m and n have the same meanings and preferred ranges.

[0022] The aromatic ring-containing amine obtained by the production method of this embodiment is more preferably represented by the following formula (S1-1). (In formula (S1-1), X is a heteroatom, and R ｓ１ is —COOH or a hydrocarbon group having 1 to 10 carbon atoms. ms is an integer of 0 to 2, and ns is 1 or 2. When ms is 2, each R ｓ１ may be the same or different.) X and R in formula (S1-1) ｓ１ , ms and ns are X and R in formula (S1), respectively. ｓ１ , ms and ns have the same meanings and preferred ranges.

[0023] Formula (S1-1) is preferably represented by formula (S2-1). (In formula (S2-1), ms2 is 0 or 1, and ns is 1 or 2.) ms2 and ns in formula (S2-1) have the same meanings as ms2 and ns in formula (S2), respectively, and the preferred ranges are also the same.

[0024] Preferred examples of amines produced by the production method of this embodiment are as follows: It goes without saying that the amines produced by the present invention are not limited to these.

[0025] In this embodiment, a hydrogen source and a nitrogen source are supplied to an acetal compound containing an aromatic ring to cause an amination reaction of the acetal group. The hydrogen source and the nitrogen source may be supplied simultaneously, or the hydrogen source may be supplied first, or the nitrogen source may be supplied first.

[0026] The hydrogen source is not particularly limited as long as it can supply a hydrogen source capable of reducing an acetal compound containing an aromatic ring, but hydrogen is preferred. The production method of this embodiment is preferably carried out under pressure with hydrogen. The pressure of hydrogen is preferably 1 bar or more and 10 bar or less.

[0027] The nitrogen source is not particularly limited, but preferably contains ammonia and / or an ammonium salt, and more preferably contains an ammonium salt. The ammonium salt can be a salt obtained by neutralizing an organic acid or an inorganic acid with ammonia. Examples of ammonium salts of organic acids include ammonium carbonate, ammonium formate, ammonium acetate, ammonium propionate, ammonium butyrate, ammonium isobutyrate, ammonium oxalate, ammonium succinate, ammonium adipate, ammonium benzoate, and diammonium phthalate. Examples of ammonium salts of inorganic acids include ammonium phosphate, monoammonium phosphate, diammonium phosphate, ammonium borate, ammonium pentaborate, and ammonium tetraborate. Among these, ammonium salts of organic acids are preferred, and more preferably contain at least one selected from the group consisting of ammonium carbonate, ammonium formate, ammonium acetate, ammonium propionate, and ammonium butyrate, and even more preferably contain ammonium acetate.

[0028] In the production method of this embodiment, the amount of the nitrogen source is preferably 1 mole or more, and may be 4 moles or more, per mole of the raw material (the acetal group contained in the acetal compound containing an aromatic ring). Furthermore, the amount of the nitrogen source is preferably 50 moles or less, and may be 40 moles or less, 30 moles or less, 20 moles or less, or 15 moles or less, per mole of the raw material (the acetal group contained in the acetal compound containing an aromatic ring). In the production method of this embodiment, only one nitrogen source may be used, or two or more nitrogen sources may be used. When two or more nitrogen sources are used, the total amount is preferably within the above range.

[0029] In this embodiment, the amination reaction is preferably carried out in the presence of a metal catalyst. The use of a metal catalyst allows the reduction by hydrogen to proceed effectively. A wide variety of metal catalysts used in reduction by hydrogen can be used as the metal catalyst, and the type thereof is not particularly specified. Metal catalysts are preferably metallic nickel, metallic cobalt, nickel compounds, or cobalt compounds, with metallic nickel, metallic cobalt, nickel phosphide, and cobalt phosphide being more preferred. Among these, cobalt phosphide is preferred, and cobalt phosphide particles are more preferred. For details about cobalt phosphide, please refer to the description in JP 2021-013923 A, the contents of which are incorporated herein by reference. When using a metal catalyst in the production method of this embodiment, the amount of the metal catalyst is preferably 0.01 mol or more per 1 mol of the raw material (acetal group contained in the acetal compound containing an aromatic ring), and may be 0.05 mol or more, or may be 0.08 mol or more. The amount of the catalyst may be 10 moles or less, 5 moles or less, 3 moles or less, 0.4 moles or less, or 0.2 moles or less per mole of the raw material (acetal group contained in the acetal compound containing an aromatic ring). In the production method of this embodiment, only one metal catalyst may be used, or two or more metal catalysts may be used. When two or more metal catalysts are used, it is preferable that the total amount is within the above range.

[0030] In this embodiment, the amination reaction is preferably carried out in the presence of a solvent. ｍ (where A is a hydrocarbon group having 1 to 10 carbon atoms, and m is 1 or 2). Use of such a solvent allows the amination reaction to proceed quickly. The solvent used in this embodiment preferably contains water. When the solvent contains water, the effect of improving the reaction rate is obtained. On the other hand, in this embodiment, it is also preferable not to supply water to the reaction system of the amination reaction. In this case, the reaction can also proceed with moisture from the air or the like.

[0031] A-(OH) ｍ In the compound represented by the formula (I), A is preferably a hydrocarbon group having 1 to 10 carbon atoms, more preferably a hydrocarbon group having 1 to 5 carbon atoms, and even more preferably a hydrocarbon group having 1 to 3 carbon atoms. The hydrocarbon group is preferably an alkyl group. In this embodiment, when m is 1, A is preferably a methyl group or an ethyl group, and more preferably a methyl group. In this embodiment, when m is 2, A is preferably an ethylene group, a propylene group, or a butylene group. A-(OH) ｍ In the compound represented by the formula: m is preferably 1.

[0032] A-(OH) ｍ Specific examples of the compound represented by the formula (I) include alkyl monoalcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, isobutanol, tert-butanol, 3-pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol, 2-methyl-2-butanol, 3-methyl-2-butanol, and neopentyl alcohol, and alkylene diols such as ethylene glycol, 1,3-propanediol, and 1,4-butanediol. Alkyl monoalcohols are preferred, methanol and ethanol are more preferred, and methanol is even more preferred.

[0033] A first embodiment of the solvent in the production method of this embodiment is A-(OH) ｍ The volume ratio of the compound represented by A-(OH) ｍ The ratio of water to the compound 1 represented by the formula (I) is 0 or more and less than 1. By adopting such a constitution, the generation of by-products can be more effectively suppressed. In the first embodiment of the solvent, the ratio of water to the compound A-(OH) ｍ The volume ratio of the compound represented by A-(OH) ｍ The ratio of water to compound 1 represented by the formula (I) may be 0.1 or more, or may be 0.3 or more, and is preferably 0.9 or less, and more preferably 0.7 or less. ｍ The volume ratio of the compound represented by A-(OH) ｍ In a second embodiment of the solvent, the ratio of water to the compound represented by the formula (I) is greater than 0 and less than 1. ｍ The volume ratio of the compound represented by A-(OH) ｍ The ratio of water to compound 1 represented by the formula (I) may be 0.1 or more, or may be 0.3 or more, and is preferably 0.9 or less, and more preferably 0.7 or less. By employing the second embodiment of the solvent, it is possible to achieve a particularly well-balanced improvement in the suppression of by-product formation and the rapid progress of the amination reaction. In the production method of this embodiment, A-(OH) ｍ The compound represented by the formula (I) may be used alone or in combination of two or more. When two or more compounds are used, the total amount is preferably in the above range.

[0034] The solvent used in this embodiment is A-(OH) ｍ The total amount of the compound represented by the formula (wherein A-(OH) ｍ and water) preferably accounts for 90% by volume or more of the solvent, more preferably 95% by volume or more, and even more preferably 99% by volume or more.

[0035] The reaction temperature of the amination reaction in the production method of this embodiment is preferably 50°C or higher, more preferably 90°C or higher, even more preferably 95°C or higher, still more preferably 100°C or higher, and even more preferably 105°C or higher. The reaction temperature of the amination reaction is preferably 200°C or lower, more preferably 150°C or lower, even more preferably 140°C or lower, still more preferably 130°C or lower, and even more preferably 125°C or lower. In the production method of this embodiment, the reaction temperature may be the same except for the initial temperature increase and the final temperature decrease (with a ±5°C variation allowed as an error), or the reaction may be carried out in two or more stages. In this embodiment, the reaction temperature is preferably the same except for the initial temperature increase and the final temperature decrease (with a ±5°C variation allowed as an error).

[0036] The reaction time of the amination reaction in the production method of this embodiment is preferably 1 minute or longer, and may be 30 minutes or longer, 1 hour or longer, or 2 hours or longer. The reaction time of the amination reaction may be 50 hours or shorter, 30 hours or shorter, 20 hours or shorter, or 9 hours or shorter.

[0037] The reaction mixture and the catalyst after the reaction can be separated by a common method such as sedimentation, centrifugation, or filtration. The catalyst is preferably separated under an inert gas atmosphere such as nitrogen or argon, depending on the catalyst used, to prevent ignition. The reaction mixture may be concentrated as needed, and the residue may be used as a raw material or intermediate, or the reaction mixture may be purified by appropriate post-treatment. Specific post-treatment methods include known purification methods such as extraction, distillation, and chromatography. Two or more of these purification methods may be combined.

[0038] In the production method of this embodiment, the higher the raw material conversion rate of the acetal compound containing an aromatic ring, the better, preferably 35% or more, more preferably 50% or more, even more preferably 80% or more, and even more preferably 90% or more. The upper limit is ideally 100 mol%, but even if it is 99.99% or less, the required performance is met. In the production method of this embodiment, the higher the selectivity of the amine compound containing an aromatic ring, the better, preferably 30% or more, more preferably 50% or more, even more preferably 70% or more, and even more preferably 80% or more. The upper limit is ideally 100 mol%, but even if it is 99% or less, the required performance is met. The raw material addition rate and selectivity are measured according to the descriptions in the examples below.

[0039] The present invention will be explained in more detail below with reference to examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below. If the measuring instruments used in the examples are difficult to obtain due to discontinuation or the like, measurements can be made using other instruments with equivalent performance.

[0040] Synthesis example of cobalt phosphide catalyst Cobalt chloride (CoCl ２ ) (1.0 mmol), hexadecylamine (10 mmol), triphenyl phosphite (10 mmol), and 1-octadecene (10.0 mL) were added to a Schlenk flask and stirred. The mixture was heated to 150°C for 1 hour under argon flow. The temperature was then raised to the solvent boiling point (approximately 290°C) over 20 minutes and maintained at that temperature for 2 hours. The mixture was then cooled to 200°C and rapidly cooled to room temperature in a water bath to obtain a black product. The resulting black product was washed with acetone, precipitated, recovered, further washed with chloroform and acetone, and dried in the air to obtain a cobalt phosphide catalyst.

[0041] Example 1 Amination was carried out according to the following scheme. Specifically, 0.5 mmol of the following raw material (FFCA-acetal), 3 mL of solvent, 0.05 mmol of the cobalt phosphide catalyst obtained above, and 5 mmol of a nitrogen source (ammonium acetate salt) were charged into an autoclave, and the reaction was carried out for 1.5 hours at a hydrogen pressure of 5 bar and a reaction temperature of 120°C. The solvent used was a mixture of water and methanol (MeOH) in a volume ratio of 1:2.

[0042] In the above scheme, NH ４ OAc represents ammonium acetate. The conversion rate was calculated by quantifying the raw materials by HPLC (High Performance Liquid Chromatography). The conversion rate was expressed in %. The results are shown in Table 1.

[0043] The reaction mixture was subjected to HPLC analysis to identify and quantify the raw materials and products. The selectivity of AMFCA in the product was calculated. The selectivity refers to the ratio (unit: %) of the number of moles of AMFCA to the total number of moles of the product. The results are shown in Table 1.

[0044] Examples 2 and 3, Reference Examples 1 and 2 The same procedures as in Example 1 were carried out except for the changes shown in Table 1. In Table 1, FFCA represents 5-formyl-2-furancarboxylic acid.

[0045]

Claims

1. A method for producing an amine containing an aromatic ring, comprising supplying a hydrogen source and a nitrogen source to an acetal compound containing an aromatic ring, and causing an amination reaction to proceed.

2. The process of claim 1 wherein the hydrogen source is hydrogen.

3. The method according to claim 1 or 2, wherein the amination reaction is carried out in the presence of a metal catalyst.

4. The method according to claim 1 or 2, wherein the acetal compound containing an aromatic ring contains an aromatic heterocycle.

5. The method according to claim 1 or 2, wherein the acetal compound containing an aromatic ring contains a furan ring.

6. The method according to claim 1 or 2, wherein the acetal compound containing an aromatic ring contains 1 to 3 acetal groups in one molecule.

7. The method according to claim 1 or 2, wherein the acetal compound containing an aromatic ring is represented by the following formula (S1): 【Chemical 1】 (In formula (S1), X is a heteroatom, and R ｓ１ is —COOH or a hydrocarbon group having 1 to 10 carbon atoms, and R ｓ２ and R ｓ３ are each independently a hydrocarbon group having 1 to 10 carbon atoms, and R ｓ２ and R ｓ３ may be bonded to each other to form a ring. ms is an integer of 0 to 2, and ns is 1 or 2. When ms is 2, each R ｓ１ may be the same or different. When ns is 2, each acetal group may be the same or different.

8. The method according to claim 1 or 2, wherein the acetal compound containing an aromatic ring is represented by the following formula (S2): 【Chemistry 2】 (In formula (S2), R ｓ２ and R ｓ３ are each independently a hydrocarbon group having 1 to 10 carbon atoms, and R ｓ２ and R ｓ３ may be bonded to each other to form a ring. ms2 is 0 or 1, and ns is 1 or 2. When ns is 2, the acetal groups may be the same or different.

9. The method according to claim 1 or 2, wherein the nitrogen source comprises ammonia and / or an ammonium salt.

10. The method according to claim 1 or 2, wherein the nitrogen source comprises an ammonium salt of an organic acid.

11. The method according to claim 1 or 2, wherein the amination reaction is carried out in the presence of a solvent.

12. The solvent is A-(OH) ｍ (wherein A is a hydrocarbon group having 1 to 10 carbon atoms, and m is 1 or 2).

13. A-(OH) in the solvent ｍ The volume ratio of the compound represented by A-(OH) ｍ The method according to claim 12, wherein the amount of water is 0 or more and less than 1 relative to 1 of the compound represented by the formula:

14. The A-(OH) ｍ The volume ratio of the compound represented by A-(OH) ｍ The method according to claim 12, wherein the amount of water is greater than 0 and less than 1 relative to 1 of the compound represented by the formula:

15. The A-(OH) ｍ The method according to claim 12, wherein the compound represented by the formula (I) comprises methanol.

16. The method of claim 11 , wherein the solvent comprises water.

17. The production method according to claim 1 or 2, wherein water is not supplied to the reaction system of the amination reaction.

18. The production method according to claim 1 or 2, comprising adding the acetal compound containing an aromatic ring to a reaction system.

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