JP6985696B2 - A catalyst composition for producing an aromatic carboxylic acid or an ester thereof from carbon dioxide and an aromatic halogen compound, and a method for producing an aromatic carboxylic acid or an ester thereof using the catalyst composition. - Google Patents

Description

The present invention is a catalyst composition for producing an aromatic carboxylic acid or an ester thereof from carbon dioxide and an aromatic halogen compound, and more particularly, a specific photooxidation-reduction catalyst component (A) and a specific transition metal catalyst component. (B) The present invention relates to a catalyst composition containing and. The present invention also relates to a method for producing an aromatic carboxylic acid or an ester thereof using the catalyst composition.

In recent years, attention has been paid to a reaction of carboxylating an organic halogen compound with carbon dioxide using a transition metal catalyst component such as Pd, Ni and Cu. Specifically, a method of directly carboxylating an aromatic bromide by reacting with carbon dioxide in the presence of a palladium catalyst is known (Non-Patent Document 1). Further, a method of carboxylating an aromatic chloride or vinyl chloride by reacting with carbon dioxide in the presence of a nickel catalyst is also known (Non-Patent Document 2).

On the other hand, as a reaction that does not require a metal reducing agent, a catalytic cycle that hydrocarboxylates alken by reacting with carbon dioxide by irradiating visible light in the presence of the Rh (I) complex and a photooxidation-reduction catalyst component is known. (Non-Patent Document 3).

Arkaitz Correa, and Ruben Martin, Palladium-Catalyzed Direct Carboxylation of Aryl Bromides with Carbon Dioxide, J.AM.CHEM.SOC.2009,131,15974-15975, DOI: 10.1021 / ja905264a Tetsuaki Fujihira, Keisuke Nogi, Tinghua Xu, Jun Terao, and Yasushi Tsuji, Nickel-Catalyzed Carboxylation of Aryl and Vinyl Chlorides Employing Carbon Dioxide, J.AM.CHEM.SOC.2012,134,9106-9109, DOI: 10.1021 / ja303514b Kei Murata, Nobutsugu Numasawa, Katsuya Shimomaki, Jun Takaya, and Nobuharu Iwasawa, Construction of a visible light-driven hydrocarboxylation cycle of alkenes by the combined use of Rh (I) and photoredox catalysts, ChemComm, 2017, DOI: 10.1039 / c7cc00678k

The methods described in Non-Patent Documents 1 and 2 require a large amount of metal reducing agent such as _{Et 2 Zn and Mn, which is not preferable from the environmental point of view.} Further, in Non-Patent Document 3, although the olefin has been successfully hydrocarboxylated by the photooxidation-reduction catalytic reaction, the carboxylation of the aromatic halogen compound has not been achieved yet.

Therefore, an object of the present invention is to solve the above-mentioned problems. That is, the present invention is a catalyst composition for carboxylating an aromatic halogen compound without using a metal reducing agent containing a transition metal element such as Zn or Mn (transition metal element belonging to Group 7 or Group 12 of the Periodic Table). The purpose is to provide.

By using a catalyst composition containing a specific photooxidation-reduction catalyst component and a specific transition metal catalyst component, the present inventors use carbon dioxide and aromatics under light irradiation conditions without using a metal reducing agent. We have found a catalytic cycle for producing aromatic carboxylic acids or esters thereof from halogen compounds.

That is, the present invention provides the following specific embodiments.
[1] A photooxidation-reduction catalyst component (A) containing a transition metal M belonging to groups 8 to 10 of the periodic table, and a transition metal catalyst containing a transition metal M'belonging to groups 8 to 11 of the periodic table and different from the transition metal M. Containing component (B),
A catalyst composition for producing an aromatic carboxylic acid or an ester thereof from carbon dioxide and an aromatic halogen compound under light irradiation conditions.

[2] The catalyst composition according to [1], wherein the photooxidation-reduction catalyst component (A) is a compound represented by the general formula (1).
(NC) _3-x (NN) _x M (1)
(N in the general formula (1) represents a nitrogen atom, C represents a carbon atom, and NC represents a bidentate ligand that coordinates the transition metal M with the nitrogen atom and the carbon atom. , N—N represent a bidentate ligand that coordinates the transition metal M with a nitrogen atom and a nitrogen atom, and x represents an integer of 0 to 3).
[3] The catalyst composition according to [1] or [2], wherein the transition metal M is iridium or ruthenium.
[4] The catalyst composition according to any one of [1] to [3], wherein the transition metal M'is at least one selected from the group consisting of palladium, cobalt, nickel and iron.
[5] The catalyst composition according to any one of [1] to [4], wherein the transition metal catalyst component (B) contains a phosphorus atom.

[6] A photooxidation-reduction catalyst component (A) containing a transition metal M belonging to groups 8 to 10 of the periodic table, and a transition metal catalyst containing a transition metal M'belonging to groups 8 to 11 of the periodic table and different from the transition metal M. A method for producing an aromatic carboxylic acid or an ester thereof, which comprises a step of irradiating carbon dioxide and an aromatic halogen compound with light in the presence of a catalyst composition containing the component (B).
[7] The method for producing an aromatic carboxylic acid or an ester thereof according to [6], wherein the aromatic halogen compound is an aromatic chloride, an aromatic bromide or an aromatic iodine product.
[8] The method for producing an aromatic carboxylic acid or an ester thereof according to [6] or [7], wherein a tertiary amine compound is present together with the catalyst composition.
[9] The method for producing an aromatic carboxylic acid or an ester thereof according to any one of [6] to [8], wherein a basic compound is present together with the catalyst composition.

According to the catalyst composition according to the present invention, the aromatic halogen compound can be carboxylated without using a metal reducing agent. Further, according to the production method according to the present invention, an aromatic carboxylic acid or an ester thereof can be produced from carbon dioxide and an aromatic halogen compound by light irradiation in the presence of a specific catalyst composition, so that a metal reducing agent can be used. It is unnecessary and can reduce the environmental load.

Hereinafter, embodiments of the present invention will be described in detail, but the following embodiments are examples for explaining the present invention, and the present invention is not limited thereto and does not deviate from the gist thereof. It can be changed arbitrarily within the range. In addition, in this specification, when a numerical value or a physical property value is inserted before and after using "~", it is used as including the numerical value or the physical property value before and after that. For example, the notation of the numerical range of "1 to 100" includes both the lower limit value "1" and the upper limit value "100", and represents "1 or more and 100 or less". The same applies to the notation of other numerical ranges.

1. 1. Catalyst Composition The catalyst composition of the present embodiment is used for producing an aromatic carboxylic acid or an ester thereof from carbon dioxide and an aromatic halogen compound under light irradiation conditions, and belongs to Groups 8 to 10 of the Periodic Table. It is characterized by containing a photooxidation-reduction catalyst component (A) containing a transition metal M and a transition metal catalyst component (B) containing a transition metal M'that belongs to groups 8 to 11 of the periodic table and is different from the transition metal M. And.
According to the catalyst composition of the present embodiment, the transition metal catalyst from the photooxidation-reduction catalyst component (A) excited under light irradiation conditions at the stage of desorption of halogen anion and reductive desorption of aromatic carboxylic acid. It is presumed that the reaction proceeds by passing electrons to the component (B).

Hereinafter, the components contained in the catalyst composition of the present embodiment will be described in the order of the photooxidation-reduction catalyst component (A) and the transition metal catalyst component (B).

[Photooxidation-reduction catalyst component (A)]
The photooxidation-reduction catalyst component (A) contains a transition metal M belonging to groups 8 to 10 of the periodic table. The transition metal M is not particularly limited as long as it is a transition metal element belonging to groups 8 to 10 of the periodic table, but is preferably iridium or ruthenium, and more preferably iridium.

Such a photooxidation-reduction catalyst component (A) is preferably a compound represented by the following general formula (1).
(NC) _3-x (NN) _x M (1)
(N in the general formula (1) represents a nitrogen atom, C represents a carbon atom, and NC represents a bidentate ligand that coordinates the transition metal M with the nitrogen atom and the carbon atom, and N −N indicates a bidentate ligand that coordinates the transition metal M with a nitrogen atom and a nitrogen atom. In addition, x indicates an integer of 0 to 3. X is preferably 1 or 2, and x is preferable. Is more preferably 1.)

The bidentate ligand (NC) coordinated to the transition metal M by a nitrogen atom and a carbon atom has one or more nitrogen atoms and one or more carbon atoms in the molecule, and these Any compound may be used as long as it is a compound capable of forming a complex by forming a coordinate bond between a nitrogen atom and a carbon atom with a transition metal M and coordinating with a bidentate. Examples of such a compound include a compound having a phenylpyridine skeleton, a compound having a phenylquinoline skeleton, a compound having a phenylisoquinoline skeleton, a compound having a phenylimidazole skeleton, a compound having a pyridylpyridine skeleton, and a compound having a naphthylpyridine skeleton. , Compounds with pyridylbenzothiophene skeleton, compounds with phenylbenzothiazole skeleton, compounds with isoquinolylbenzothiophene skeleton, compounds with phenylquinoxaline skeleton, compounds with phenylbenzoisoquinoline skeleton, compounds with phenylpyrazole skeleton, phenyl Examples thereof include a compound having a tetrazole skeleton, a compound having a phenylbenzoimidazole skeleton, and the like. Among these, a compound having a phenylpyridine skeleton is preferable, and a compound having a 2-phenylpyridine skeleton is more preferable.

Examples of the compound having a 2-phenylpyridine skeleton include 2-phenylpyridine and its derivatives. Here, the derivative of 2-phenylpyridine includes 2-phenylpyridine having a substituent. The substituent contained in such a derivative is not particularly limited, but for example, an alkyl group having 1 to 10 carbon atoms (C _{1 to 10} alkyl group) such as a methyl group or an ethyl group, or a methoxy group or an ethoxy group has a carbon number of carbon atoms. Examples thereof include an alkoxy group having 1 to 10 (C _{1 to 10} alkoxy group), a halogen atom such as a fluorine atom, and an alkyl group containing a fluorine atom such as a trifluoromethyl group.

When the compound having a 2-phenylpyridine skeleton has a substituent, the number of substituents is not particularly limited, but is usually 1 or more, preferably 2 or more, and usually 6 or less, preferably 4 or less. For example, a compound having a 2-phenylpyridine skeleton preferably has a substituent at at least one of the 5,4', 6'positions, and more preferably a substituent at the 5,4', 6'position. ..

Further, the bidentate ligand (NN) coordinated to the transition metal M by the nitrogen atom and the nitrogen atom has two or more nitrogen atoms in the molecule, and these nitrogen atoms are the transition metal M. Any compound can be used as long as it can form a complex by forming a coordination bond with and in a bidentate coordination. Examples of such a compound include a compound having a bipyridine skeleton such as bipyridine and its derivative, a compound having a phenanthroline skeleton such as phenanthroline and its derivative, and ethylenediamine. Among these, a compound having a bipyridine skeleton and a compound having a phenanthroline skeleton are preferable, and a compound having a bipyridine skeleton is more preferable. Further, among the compounds having a bipyridine skeleton, a compound having a 2,2'-bipyridine skeleton is preferably used. Among the compounds having a phenanthroline skeleton, compounds having a 1,10-phenanthroline skeleton are preferably used.
The bipyridine derivative includes bipyridine having a substituent. In addition, the derivative of phenanthroline includes phenanthroline having a substituent. The substituents of these derivatives are not particularly limited, but for example, an alkyl group having 1 to 10 carbon atoms (C _{1 to 10} alkyl group) such as a methyl group, an ethyl group, an isopropyl group and a t-butyl group, a methoxy group and the like. Examples thereof include an alkoxy group having 1 to 10 carbon atoms (C _{1 to 10} alkoxy group) such as an ethoxy group and a phenyl group. As these substituents, a C _{1 to 10} alkyl group and a C _{1 to 10} alkoxy group are preferable, a C _{1 to 5} alkyl group and a C _{1 to 5} alkoxy group are more preferable, and a C _{1 to 5} alkyl group is particularly preferable. In addition, these substituents may have another substituent.

When the compound having a 2,2'-bipyridine skeleton or the compound having a 1,10-phenanthroline skeleton has a substituent, the number of substituents is not particularly limited, but is usually 1 or more, preferably 2 or more, and usually 6 Hereinafter, it is preferably 4 or less. For example, a compound having a 2,2'-bipyridine skeleton preferably has a substituent at at least one of the 4,4'positions, and more preferably has a substituent at the 4,4'position. Further, the compound having a 1,10-phenanthroline skeleton preferably has a substituent at at least one of the 3,4,7,8 positions, and more preferably has a substituent at the 3,4,7,8 position. preferable.

The above bidentate ligands can be used alone or in combination of two or more.

Preferred specific examples of the photooxidation-reduction catalyst component (A) include, for example, tris (2,2'-bipyridine) ruthenium dichloride (Ru (bpy) ₃ Cl ₂ ), tris (2,2'-bipyridine) ruthenium bis ( Hexafluorophosphate) (Ru (bpy) ₃ (PF ₆ ) ₂ ), Tris (2- (2-pyridinyl-κN) phenyl-κC) Iridium (fac-Ir (ppy) ₃ ), Bis (2- (2-) Pyridinyl-κN) phenyl-κC) (4,4'-ditersary butyl-2,2'-bipyridine) iridium (hexafluorophosphate) (Ir (ppy) ₂ (dtbbpy) (PF ₆ )), bis (2- (5-Trifluoromethylpyridine-2-yl-κN) -4,6-difluorophenyl-κC) (4,4'-ditersary butyl-2,2'-bipyridine) Iridium (hexafluorophosphate) (Ir ( dF (CF ₃ ) ppy) ₂ (dtbbpy) (PF ₆ )), bis (2- (5-trifluoromethylpyridine-2-yl-κN) -4,6-difluorophenyl-κC) (2,2' -Bipyridine) Iridium (hexafluorophosphate) (Ir (dF (CF ₃ ) ppy) ₂ (bpy) (PF ₆ )), bis (2- (pyridinyl-κN) phenyl-κC) (4,4'-dimethoxy- 2,2'-Dipyridinyl) Iridium (hexafluorophosphate) (Ir (ppy) ₂ (dmobpy) (PF ₆ )), Bis (2- (pyridinyl-κN) phenyl-κC) (4,4'-diphenyl-2 , 2'-dipyridinyl) iridium (hexafluorophosphate) (Ir (ppy) ₂ (bpbpy) (PF ₆ )), bis (2- (pyridinyl-κN) phenyl-κC) (1,10-phenanthroline) iridium (hexa) Fluorophosphate) (Ir (ppy) ₂ (phen) (PF ₆ )), bis (2- (pyridinyl-κN) phenyl-κC) (3,4,7,8-tetramethyl-1,10-phenanthroline) iridium (Hexafluorophosphate) (Ir (ppy) ₂ (Me ₄ phen) (PF ₆ )) and the like can be mentioned. These photooxidation-reduction catalyst components (A) may be used alone or in combination of two or more.

From the viewpoint of excellent yield of aromatic carboxylic acid, more preferable specific examples of the photooxidation-reduction catalyst component (A) are Ir (dF (CF ₃ ) ppy) ₂ (dtbbpy) (PF ₆ ), Ir (ppy) _2. (dtbbpy) (PF ₆ ), Ir (ppy) ₂ (dmobpy) (PF ₆ ), Ir (ppy) ₂ (bpbpy) (PF ₆ ) and Ir (ppy) ₂ (Me ₄ phen) (PF ₆ ). Further preferred specific examples are Ir (ppy) ₂ (dtbbpy) (PF ₆ ) and Ir (ppy) ₂ (dmobpy) (PF ₆ ), and particularly preferable specific examples are Ir (ppy) ₂ (dtbbpy) (PF). ₆ ).

The content ratio of the photooxidation-reduction catalyst component (A) in the catalyst composition is not particularly limited, but is usually 0.01 mol% or more, preferably 0.01 mol% or more, based on the aromatic halogen compound which is the starting material (substrate) of the carboxylation reaction. It is 0.1 mol% or more, more preferably 0.5 mol% or more, usually 20 mol% or less, preferably 10 mol% or less, and more preferably 5 mol% or less.
If the content of the photooxidation-reduction catalyst component (A) is small, the catalytic cycle may not proceed sufficiently. On the other hand, if the content ratio of the photooxidation-reduction catalyst component (A) is large, the effect tends not to be significantly improved, which is not economical.

[Transition metal catalyst component (B)]
The transition metal catalyst component (B) belongs to the groups 8 to 11 of the periodic table and contains a transition metal M'different from the transition metal M contained in the photooxidation-reduction catalyst component (A).
The transition metal M'is not particularly limited as long as it is a transition metal element belonging to Groups 8 to 11 of the Periodic Table, but a transition metal element other than rhodium is preferable, and at least one selected from the group consisting of palladium, cobalt, nickel and iron. Species are more preferred, palladium or nickel is even more preferred, and palladium is particularly preferred.

Further, the transition metal catalyst component (B) preferably contains a phosphorus atom. Such a transition metal catalyst component (B) is a complex composed of a catalyst precursor containing a transition metal M'and a monodentate ligand containing a phosphorus atom.

Specific examples of the catalyst precursor containing palladium include, for example, Pd (PPh ₃ ) ₄ , Pd (P (o-trol) ₃ ) ₄ , Pd (P (tBu) ₃ ) ₄ , Pd ₂ (dba) ₃ , Pd ₂ (dba) ₃ · CHCl ₃ , Pd (dba) ₂ , Pd (MeCN) ₄ (BF ₄ ) ₂ , PdCl ₂ , PdBr ₂ , Pd (acac) ₂ , Pd (TFA) ₂ , Pd (allly) Cl ₂ , [(allly) PdCl] ₂ , Pd (PCy ₃ ) ₂ Cl ₂ , Pd (P (o-toll) ₃ ) ₂ Cl ₂ , Pd (OAc) ₂ , PdCl ₂ (dppff), PdCl ₂ (dppf) CH ₂ Cl ₂ , Pd (MeCN) ₂ Cl ₂ , Pd (amPhos) Cl ₂ , PdCl ₂ (dtbpf) or PdCl ₂ (PPh ₃ ) _2, etc., and palladium is 0 or divalent.
In the present specification, Ph is a phenyl group, o-tol is an o-tolyl group, tBu is a tert-butyl group, dba is dibenzylidene acetone, MeCN is acetonitrile, acac is acetylacetonate, and TFA is trifluoroacetate. OAc is acetate, allyl is allyl, Cy is cyclohexyl group, dppf is 1,1'-bis (diphenylphosphino) ferrocene, dtbpf is 1,1'-di-tert-butylphosphinoferosen, PPh ₃ is tri Phenylphosphin, amPhos represents [4- (N, N-dimethylamino) phenyl] di-tert-butylphosphine.
These catalyst precursors may be used alone or in combination of two or more.
_{Among these, Pd (OAc) 2} and [(allyl) PdCl] ₂ are preferable, and Pd (OAc) ₂ is more preferable, from the viewpoint of excellent yield of aromatic carboxylic acid.

The monodentate ligand containing a phosphorus atom (hereinafter, may be simply referred to as “ligand”) has one or more phosphorus atoms in the molecule, and this phosphorus atom is a transition metal M'. Any compound can be used as long as it can form a complex by forming a coordination bond with and in a monodentate coordination.
As such a compound, it is preferable to use an organic phosphorus compound represented by the _{general formula P (R x} ) _3. R _x represents a substituent attached to the phosphorus atom (P). _Rx is a substituted or unsubstituted C _{1 to 30} alkyl group, a substituted or unsubstituted C _{1 to 30} cycloalkyl group, and a substituted or unsubstituted ring-forming aromatic hydrocarbon group having 6 to 30 carbon atoms. Is preferable. A plurality of R _x may be the same as or different from each other. Further, as the organic phosphorus compound, _{a phosphine salt represented by the general formula P (R x} ) _3. (HX _a ) can also be used. R _x has the same meaning as described above, H is a hydrogen atom, X _a represents an atom or an atomic group _{, and examples of HX a} include HCl, HBr, and HBF ₄ .

Examples of the organic phosphorus compound include triphenylphosphine (PPh ₃ ), trimethylphosphine (PMes ₃ ), tricyclohexylphosphine (PCy ₃ ), tri (t-butyl) phosphine (P (tBu) ₃ ), and tri-tert. -Butylphosphonium tetrafluorobolate (PtBu ₃ -HBF ₄ ), tri-o-triphenylphosphine (P (o-tol) ₃ ), tri-p-tolylphosphine (P (p-tol) ₃ ), tris (p) -Methoxyphenyl) phosphine (P (p-MeOC ₆ H ₄ ) ₃ ), tris (o-methoxyphenyl) phosphine (P (o-MeOC ₆ H ₄ ) ₃ ), triphenylphosphine (P (furanyl) ₃ ) , Triphenylphosphine (P (thienyl) ₃ ), tris (3,5-dimethoxyphenyl) phosphine (P (3,5- (MeO) ₂ C ₆ H ₃ ) ₃ ), dicyclohexylphenylphosphine (PPh (Cy) ₂ ), Cyclohexyldiphenylphosphine (PPh ₂ (Cy)), dicyclohexylphosphine (HPCy ₂ ), di-tert-butylphosphine (HP (tBu) ₂ ), di-tert-butylchlorophosphine (P () tBu) ₂ Cl), trimethylphosphine (P (OMe) ₃ ), triphenylphosphine (P (OPh) ₃ ), diphenylphosphine oxide (HPOPh ₂ ), tris (dimethylamino) phosphine (HMPT), tris (diethylamino) ) Phosphine (P (NEt ₂ ) ₃ ), 5- (di-t-butylphosphino) -1', 3', 5'-triphenyl-1'H- [1,4'] bipyrazole (BippyPhos), 1,2,3,4,5-pentaphenyl-1'-(di-t-butylphosphine) ferrocene (QPhos), 1,3,5-triaza-7-phosphaadamantan (PTA), bis [2] -(Diphenylphosphine) phenyl] ether (DPEPhos), 1,1'-bis (diphenylphosphino) ferrocene (dppf), 1,1'-bis (diphenylphosphino) methane (dppm), 1,2-bis (Diphenylphosphine) ethane (dppe), 1,3-bis (diphenylphosphino) propane (dppp), 1,4-bis (diphenylphosphino) butane (dppb), 1,2-bis (dicyclohexyl) Phosphino) ethane (dcpe), 1,1'-bis (di-tert-butylphosphino) ferrocene (dtbpf), 2,2'-bis (diphenylphosphino) -1,1'-binaphthyl (BINAP), 2 -Dicyclohexylphosphino-2', 6'-dimethoxybiphenyl (SPhos), 2-dicyclohexylphosphino-2', 4', 6'-triisopropylbiphenyl (XPhos), 2-diphenylphosphino-2', 4' , 6'-Triisopropylbiphenyl (PhXPhos), 2-di-tert-butylphosphino-2', 4', 6'-triisopropylbiphenyl (tBuXPhos), 2-diisopropylphosphino-2', 4', 6 '-Triisopropylbiphenyl (iPrXPhos), 2-bis (p-trifluoromethylphenyl) phosphino-2', 4', 6'-triisopropylbiphenyl (Ar ^CF3 XPhos), 2- (di-tert-butylphosphino) ) Biphenyl (JohnPhos), 2- (dicyclohexylphosphino) Biphenyl (cyclohexyl JohnPhos), 2- (dicyclohexylphosphino) -2-'-methylbiphenyl (MePhos), 2- (dicyclohexylphosphino) -2', 6'- Diisopropoxy-1,1'-biphenyl (RuPhos), 2- (dicyclohexylphosphino) -3,6-dimethoxy-2', 4', 6'-triisopropyl-1,1'-biphenyl (BrettPhos), 2 '- (dicyclo to Kishiruhosufino) -2,6-dimethoxy - biphenyl-3-sulfonic acid sodium salt ^(s SPhos), 2-(diphenylphosphino) -2' - (N, N'-dimethylamino) biphenyl ( PhDavePhos), 2-di-tert-butylphosphino-3,4,5,6-tetramethyl-2', 4', 6'-triisopropyl-1,1'-biphenyl (Tetramethyl di-tBuXPhos), 2 -(Di-tert-butylphosphino) -2-'-methylbiphenyl (tBuMePhos), 2-di-tert-butylphosphino-2'-(N, N-dimethylamino) biphenyl (tBuDavePhos), 2- (bis) -[3,5-bis (trifluoromethyl) phenyl] phosphino) -3,6-dimethoxy-2', 4', 6'-triisopropyl-1,1'-biphenyl (JackiePhos) , (N-butyl) di (1-adamantyl) phosphine (cataCXium A), (n-butyl) di (1-adamantyl) phosphonium hydroiodide (cataCXium AHI), N-phenyl-2- (di-tert) -Butylphosphino) pyrrole (cataCXium PtB), 2- (di-tert-butylphosphino) -N-phenylindole (cataCXium PlntB), N-phenyl-2- (dicyclohexylphosphino) pyrrole (cataCXium PCy), N -(2-methoxyphenyl) -2- (di-tert-butylphosphino) pyrrole (cataCXium POMetB), 2- (di (1-adamantyl) phosphino)-dimethylaminobenzene (Me-DalPhos), di (1-) Adamanthyl) -2-Mor-DalPhos, 2- (Dicyclohexylphosphino) -2-'-(Dimethylamino) Biphenyl (DavePhos), and 4,5-Bis (Diphenylphosphino) -9,9- Examples thereof include dimethylxanthene (XantPhos).
Among these, XPhos, PhXPhos, iPrXPhos, Ar ^CF3 XPhos and tBuXPhos are preferable.
These organophosphorus compounds may be used alone or in combination of two or more.

Among the above organic phosphorus compounds, it is preferable that at least one of _{the substituents (R x} ) bonded to the phosphorus atom (P) is a bulky substituent. Specifically, it is preferable to at least one of R _x having at least two aromatic rings, more preferably having at least one xantphos skeleton or biphenyl skeleton of R _x, at least one of R _x have the biphenyl skeleton It is even more preferable, and it is particularly preferable that one of _{R x has a biphenyl skeleton.}
By selecting such an organic phosphorus compound, the yield of aromatic carboxylic acid is further improved.

Further, the biphenyl skeleton preferably has a substituent. Such substituents, _{C 1 to 10} alkyl group such as a methyl group, an ethyl group or an isopropyl group, _{C 1 to 10} alkyl group such as a methoxy group or an ethoxy group, a dimethylamino group, _{C 1 to 10} of diethylamino Examples thereof include a dialkylamino group having the above-mentioned alkyl group, and a _{C 1 to 5 alkyl group is preferable.} The number of substituents is not particularly limited, but is usually 1 or more, preferably 3 or more, and usually 6 or less, preferably 5 or less.

The transition metal catalyst component (B) may be prepared by reacting an organic phosphorus compound with a catalyst precursor containing a transition metal M'in advance, or may be prepared with a catalyst precursor containing a transition metal M'in the reaction system. It may be prepared in a reaction system by adding an organic phosphorus compound.
When preparing in the reaction system, the order in which the catalyst precursor containing the transition metal M'and the organophosphorus compound are added is not particularly limited, and the catalyst precursor containing the transition metal M'is added before the organophosphorus compound. It may be added later. When the transition metal catalyst component (B) is prepared in the reaction system, the presence of the transition metal catalyst component (B) includes ¹ H-NMR spectrum of ^{the transition metal catalyst component (B) prepared in advance and 1 of the catalyst composition.} It can be confirmed by comparing with the H-NMR spectrum.

The content ratio of the transition metal catalyst component (B) in the catalyst composition is not particularly limited, but is usually 0.01 mol% or more, preferably 0, with respect to the aromatic halogen compound which is the starting material (substrate) of the carboxylation reaction. .1 mol% or more, more preferably 0.5 mol% or more, usually 20 mol% or less, preferably 10 mol% or less, more preferably 5 mol% or less.
If the content of the transition metal catalyst component (B) is low, the catalytic cycle may not proceed sufficiently. On the other hand, if the content ratio of the transition metal catalyst component (B) is large, the effect tends not to be significantly improved, which is not economical.

When the transition metal catalyst component (B) is prepared in the reaction system, the content ratios of the catalyst precursor containing the transition metal M'and the organophosphorus compound are as follows.
The content ratio of the catalyst precursor containing the transition metal M'is usually 0.1 mol% or more, preferably 0.5 mol% or more, more preferably 1.0 mol% or more, still more preferably 2 with respect to the aromatic halogen compound. It is 0.0 mol% or more, usually 30 mol% or less, preferably 25 mol% or less, more preferably 20 mol% or less, still more preferably 15 mol% or less.
The content ratio of the organic phosphorus compound is usually 0.5 mol% or more, preferably 1.0 mol% or more, more preferably 2.0 mol% or more, still more preferably 3.0 mol% or more with respect to the aromatic halogen compound. It is usually 50 mol% or less, preferably 40 mol% or less, more preferably 30 mol% or less, still more preferably 25 mol% or less.
If the content of the catalyst precursor containing the transition metal M'orientation of the organic phosphorus compound is small, the amount of the transition metal catalyst component (B) produced may be small and the catalytic cycle may not proceed sufficiently.
On the other hand, if the content of the catalyst precursor containing the transition metal M'and the content of the organic phosphorus compound are high, the effect tends not to be significantly improved, which is not economical. In addition, the catalytic cycle may not proceed sufficiently due to the residue (excessive amount of catalyst precursor or organophosphorus compound) after the transition metal catalyst component (B) is produced.

The molar ratio of the organophosphorus compound to the catalyst precursor containing the transition metal M'(organophosphorus compound / catalyst precursor) is usually 0.1 or more, preferably 0.5 or more, and more preferably 1 or more. It is usually 20 or less, preferably 10 or less, and more preferably 5 or less.
If the molar ratio of the organic phosphorus compound to the catalyst precursor containing the transition metal M'is small, the amount of the transition metal catalyst component (B) produced may be small, and the catalytic cycle may not proceed sufficiently. On the other hand, if the molar ratio of the organic phosphorus compound to the catalyst precursor containing the transition metal M'is large, the effect tends not to be significantly improved, which is not economical. Further, if the molar ratio of the organophosphorus compound to the catalyst precursor containing the transition metal M'is too small or too large, the residue after the transition metal catalyst component (B) is generated (excessive amount of catalyst precursor). Alternatively, the catalytic cycle may not proceed sufficiently due to the organophosphorus compound).

The molar ratio (B / A) of the transition metal catalyst component (B) to the photooxidation-reduction catalyst component (A) is usually 1/20 or more, preferably 1/10 or more, more preferably 1/5 or more, and is usually used. It is 20/1 or less, preferably 15/1 or less, and more preferably 10/1 or less.
If the molar ratio of the transition metal catalyst component (B) to the photooxidation-reduction catalyst component (A) is too small or too large, the catalytic cycle may not proceed sufficiently. In addition, an excessive amount of the component may remain in the reaction system and affect the catalytic cycle.

2. 2. Method for producing aromatic carboxylic acid or ester thereof The method for producing aromatic carboxylic acid or its ester in the present embodiment comprises a photooxidation-reduction catalyst component (A) containing a transition metal M belonging to Groups 8 to 10 of the Periodic Table and a period. A step of irradiating carbon dioxide and an aromatic halogen compound with light in the presence of a catalyst composition belonging to Groups 8 to 11 and containing a transition metal catalyst component (B) containing a transition metal M'different from the transition metal M. including.

The wavelength of the light to be irradiated may be determined according to the photooxidation-reduction catalyst component (A) to be used, but when the transition metal M contained in the photooxidation-reduction catalyst component (A) is ruthenium or iridium, visible light. It is preferable to irradiate (for example, light having a wavelength in the range of 400 to 700 nm), and more preferably to irradiate blue light (for example, light having a wavelength in the range of 400 to 500 nm). Further, the light to be irradiated may be natural light such as sunlight or artificial light using an LED or the like as a light source.

The temperature (reaction temperature) at the time of light irradiation is not particularly limited, but is usually 0 ° C. or higher, preferably 15 ° C. or higher, and usually 70 ° C. or lower, preferably 50 ° C. or lower. The reaction temperature means the temperature in the reaction vessel for producing the aromatic carboxylic acid or its ester. If the reaction temperature is too low, the catalytic cycle may not proceed sufficiently. Also, if the reaction temperature is too high, the yield of hydrogenation products tends to increase.

The time of light irradiation (reaction time) is not particularly limited, but is usually 1 hour or more, preferably 2 hours or more, and usually 24 hours or less, preferably 10 hours or less. If the reaction time is short, the catalytic cycle may not proceed sufficiently. On the other hand, even if the reaction time is long, no significant improvement in the yield of the aromatic carboxylic acid is observed, and the yield of the hydrogenation product tends to increase.

Further, the intensity of the emitted light is not particularly limited. For example, when a light irradiation device such as an LED lamp is used, the light intensity can be controlled by increasing or decreasing the number of sockets. When the intensity of the irradiated light is increased, the conversion rate of the aromatic halogen compound as a starting material may be improved.

The light irradiation step is preferably carried out by putting the catalyst composition, carbon dioxide and the aromatic halogen compound in the reaction vessel. The light irradiation step may be performed under atmospheric pressure or at a pressure higher than atmospheric pressure.
Here, carbon dioxide may be added by bubbling into the reaction system under atmospheric pressure or pressurized conditions, or liquid from the gas phase while stirring preferably up and down under atmospheric pressure or pressurized conditions. It may be dissolved in the phase.

The reaction form is not particularly limited, and may be, for example, either a continuous method or a batch method.

By the light irradiation step under the above conditions, electrons are transferred from the excited photooxidation-reduction catalyst component (A) to the transition metal catalyst component (B) at the stage of desorption of halogen anions and reductive desorption of aromatic carboxylic acid. It is passed and it is presumed that the reaction will proceed.

After completion of the reaction, the method for separating the aromatic carboxylic acid is not particularly limited, and for example, it is preferably carried out by a distillation / concentration method. As the means for this distillation / concentration, a conventional distillation / concentration device, for example, a decompression continuous distillation device, a decompression batch type distillation device, or the like can be used.

The aromatic carboxylic acid thus obtained is a compound in which the halogen atom (-X) in the aromatic halogen compound described later is replaced with a carboxy group (-COOH). Along with the aromatic carboxylic acid, a hydrogenation product can also be obtained as a by-product. The hydrogenation product is a compound in which a halogen atom (−X) in an aromatic halogen compound is replaced with a hydrogen atom (−H).

[Aromatic halogen compounds]
The aromatic halogen compound used in the production method of the present embodiment is not particularly limited as long as it contains a structure in which a halogen atom is directly chemically bonded to an atom constituting the ring of the aromatic compound. Here, examples of the "atoms constituting the ring of the aromatic compound" include carbon atoms constituting the benzene ring. The number of benzene rings may be one or two or more, and the benzene rings may have a fused ring structure such as a naphthalene ring. Further, the ring structure is not limited to the benzene ring as long as it has aromaticity, and may be a heterocyclic ring, a five-membered ring other than the six-membered ring, a seven-membered ring, or the like. Further, as the aromatic halogen compound, only one kind may be used, or a plurality of different kinds may be used in combination.

（式中、Ｘはハロゲン原子を表し、ｎ_１は１〜３の整数を表す。ｎ_１が２以上の場合には、Ｘは互いに同一でも異なっていてもよい。Ｒは水素原子、フッ素原子、塩素原子、アルキル基、フッ素原子を含有するアルキル基、アルコキシ基、シクロアルキル基、アリール基、カルボニル基、エステル基、ニトリル基又はシリル基を表し、ｎ_２は１〜３の整数を表す。ｎ_２が２以上の場合にはＲは互いに同一でも異なっていてもよい。またＲは隣接炭素原子に結合し、それらの炭素原子とともに炭化水素環又は複素環を形成してもよい。） For example, the aromatic halogen compound in the case of one benzene ring is preferably represented by the following structural formula (I).

(In the formula, X represents a halogen atom and n ₁ represents an integer of ₁ to 3. When n 1 is 2 or more, X may be the same as or different from each other. R is a hydrogen atom and a fluorine atom. , A chlorine atom, an alkyl group, an alkyl group containing a fluorine atom, an alkoxy group, a cycloalkyl group, an aryl group, a carbonyl group, an ester group, a nitrile group or a silyl group, and n ₂ represents an integer of 1 to 3. When n ₂ is 2 or more, R may be the same as or different from each other. Further, R may be bonded to an adjacent carbon atom to form a hydrocarbon ring or a heterocycle with those carbon atoms.)

From the viewpoint of excellent progress of the catalytic cycle, the halogen atom X is preferably a chlorine atom, a bromine atom or an iodine atom, and more preferably a bromine atom or a chlorine atom. That is, the aromatic halogen compound is preferably an aromatic chloride, an aromatic bromide or an aromatic iodide, and more preferably an aromatic chloride or an aromatic bromide.
Further, from the viewpoint of excellent progress of the catalytic cycle, n ₁ is preferably 1 or 2, more preferably 1 and n ₂ is preferably 1 or 2 in the structural formula (I).

When the halogen atom X is a bromine atom, specific examples of the compound represented by the structural formula (I) are shown below. These are merely examples when the halogen atom X is a bromine atom, and similar aromatic halogen compounds can be exemplified when the halogen atom X is a chlorine atom or an iodine atom. The compounds exemplified below include the o-position, the m-position, and the p-position.

Examples of the hydrogen atom in which R is a hydrogen atom include bromobenzene and the like.

Examples of the fluorine atom and / or chlorine atom in which R is fluorobromobenzene, difluorobromobenzene, chlorobromobenzene, dichlorobromobenzene, fluorochlorobromobenene and the like can be mentioned.

Examples of alkyl groups in which R is bromotoluene, bromoxylene, trimethylbromobenzene, ethylbromobenzene, methylethylbromobenzene, tert-butylbromobenzene, 2-ethylhexylbromobenzene, 2,4,6-triisopropylbromobenzene And so on. Among the alkyl groups, C _{1 to 10} alkyl groups are preferable, and C _{1 to 5} alkyl groups are more preferable.

Examples of the alkyl group in which R contains a fluorine atom include trifluoromethylbromobenzene and the like.

Examples of alkoxy groups in which R is alkoxy groups include bromoanisole, dimethoxybromobenzene, trimethoxybromobenzene, ethoxybromobenzene, methoxyethoxybromobenzene, propoxybromobenzene, ethoxypentoxybromobenzene, phenoxybromobenzene, benzoxibromobenzene and the like. Can be mentioned. Among the alkoxy groups, C _{1 to 10} alkoxy groups are preferable, and C _{1 to 5} alkoxy groups are more preferable.

Examples of the cycloalkyl group in which R is a cycloalkyl group include cyclopentylbromobenzene, cyclohexylbromobenzene, cyclooctylbromobenzene and the like.

Examples of the aryl group in which R is an aryl group include bromobiphenyl and the like.

Examples of the carbonyl group in which R is a carbonyl group include acetylbromobenzene and t-butoxycarbonylaminobromobenzene.

Examples of the ester group in which R is an ester group include methyl bromobenzoate, ethyl bromobenzoate, butyl bromobenzoate, dimethyl bromophthalate and the like.

Examples of the nitrile group in which R is a nitrile group include cyanobromobenzene and the like.

Examples of the silyl group in which R is silyl group include trimethylsilylbromobenzene, triethylsilylbromobenzene, triisopropylsilylbromobenzene, di-t-butylmethylsilylbromobenzene, triisopropylsilylethynylbromobenzene and the like.

Examples of the isopropenyl group, allyl group, and vinyl group in which R is isopropenylbromobenzene, allylbromobenzene, vinylbromobenzene, and the like can be mentioned.

Examples of the hydrocarbon ring or heterocycle in which R is a hydrocarbon ring or a heterocycle include methylenedioxybromobenzene, bromothiophene, N-tert-butoxycarbonylbromoindole, bromoindole and the like.

〔solvent〕
The carboxylation reaction of this embodiment is carried out in a reaction solvent. The reaction solvent is preferably an organic solvent, and is not particularly limited, but for example, dimethyl sulfoxide, toluene, benzene, 1,4-dioxane, ethanol, butanol, xylene, N, N-dimethylformamide (DMF), N. -Methylpyrrolidone (NMP), acetonitrile (MeCN), acetone, tetrahydrofuran (THF) and N, N-dimethylacetamide (DMA) and the like can be mentioned. Among these, DMF, NMP, acetone or DMA is preferable, DMF, NMP or DMA is more preferable, and DMA is particularly preferable, from the viewpoint of excellent yield of aromatic carboxylic acid.

[Esterification reaction]
An aromatic carboxylic acid ester can be obtained by esterifying an aromatic carboxylic acid obtained from the above aromatic halogen compound and carbon dioxide.
For the esterification reaction, a conventionally known esterification method can be adopted, for example, an alkyl esterification method (alkanol + acid catalyst), an aralkyl esterification method (aralkyl alcohol + acid catalyst), or methylation using diazomethane or trimethylsilyldiazomethane. The law etc. can be mentioned.

[Tertiary amine compound]
In the method for producing an aromatic carboxylic acid or an ester thereof in the present embodiment, it is preferable that a tertiary amine compound is present together with the catalyst composition. The tertiary amine compound can hydrate halogen ions as an electron donor and improve the yield of aromatic carboxylic acid.

_{Examples of the tertiary amine compound include N, N, N-tri (C 1-4} alkyl) amines such as trimethylamine, dimethylethylamine, triethylamine, tri (n-butyl) amine, diisopropylethylamine and diisobutylmethylamine; diethyl ( _{N- (C 1-4} alkyl) azacycloalkanes such as tetramethylsilyl) amines, N-methylpyrrolidin, N-methylpiperidine, N-ethyl-2,2,6,6-tetramethylpiperidine; N-methyl _{N- (C 1-4} alkyl) azaoxycycloalkanes such as morpholin, N-ethylmorpholin; N-benzyl-N, such as N-benzyl-N, N-dimethylamine, N-benzyl-N, N-diethylamine, etc. N- di _{(C 1 to 4} alkyl) amine; N, N- dimethylaniline or the like of N, N- di _{(C 1 to 4} alkyl) aniline; diazabicycloundecene, bicyclic amines, such as diazabicyclononene Kind: N, N, N-tri (C _1-4 alcohol) amines such as triethanolamine and the like can be mentioned. These tertiary amine compounds can be used alone or in combination of two or more.
Among these, N, N, N-tri (C _1-4 alkyl) amines are preferable, and diisopropylethylamine is more preferable, from the viewpoint of improving the yield of aromatic carboxylic acid.

The blending amount of the tertiary amine compound is not particularly limited, but is usually 1 equivalent or more, preferably 2 equivalents or more, more preferably 3 equivalents or more, and usually 20 equivalents or less, with respect to the halogen atom in the aromatic halogen compound. It is preferably 15 equivalents or less, more preferably 10 equivalents or less. By setting the blending amount of the tertiary amine compound in the above range, the yield of the aromatic carboxylic acid can be improved.

[Basic compound]
Further, in the method for producing an aromatic carboxylic acid or an ester thereof in the present embodiment, it is preferable that a basic compound is present as an additive together with the catalyst composition. The basic compound can capture the liberated acid component and improve the yield of aromatic carboxylic acid. Further, by blending a basic compound, the formation of by-products can be suppressed.

Examples of the basic compound include alkali metal hydroxides such as lithium hydroxide, sodium hydroxide, potassium hydroxide and cesium hydroxide; alkali metal carbonates such as lithium carbonate, sodium carbonate, potassium carbonate and cesium carbonate; carbonic acid. Alkaline metal hydrogen carbonates such as sodium hydrogen, potassium hydrogen carbonate, and cesium hydrogen carbonate; alkaline earth metal hydroxides such as magnesium hydroxide, calcium hydroxide, and barium hydroxide; alkalis such as magnesium carbonate, calcium carbonate, and barium carbonate. Alkali metal alkoxides such as earth metal carbonates, sodium methoxydos, sodium ethoxydos, potassium t-butoxides; alkali metal organic acid salts such as sodium acetate; amines such as triethylamine, piperidine, N-methylpiperidine, pyridine, picolin And the like, a nitrogen-containing heterocyclic compound and the like can be mentioned. These basic compounds can be used alone or in combination of two or more.
Among these, from the viewpoint of improving the yield of aromatic carboxylic acid, alkali metal carbonate is preferable, sodium carbonate, potassium carbonate or cesium carbonate is more preferable, and cesium carbonate is further preferable.

The amount of the basic compound to be blended is not particularly limited, but is usually 1 equivalent or more, preferably 2 equivalents or more, more preferably 3 equivalents or more, and usually 20 equivalents or less, preferably 20 equivalents or less, with respect to the halogen atom in the aromatic halogen compound. Is 15 equivalents or less, more preferably 10 equivalents or less. By setting the blending amount of the basic compound in the above range, the yield of the aromatic carboxylic acid can be improved.

When a tertiary amine compound and a basic compound are used in combination, the compounding ratio of the basic compound to the tertiary amine compound (calculated as an equivalent ratio to the halogen atom, basic compound / tertiary amine compound) is usually 0.1 or more. It is preferably 0.5 or more, usually 5 or less, and preferably 3 or less.

After the completion of the light irradiation step, the aromatic carboxylic acid or its ester is separated from the reactant by a conventionally known method. After separating the aromatic carboxylic acid or ester thereof, the catalytic composition in the residual liquid can be reused in a new operation and thus subjected to recirculation. The yield of the aromatic carboxylic acid or its ester is usually 2% by mass or more, preferably 10% by mass or more, more preferably 30% by mass or more, still more preferably 30% by mass, based on the total amount of the aromatic halogen compound as a starting material. It is 50% by mass or more, particularly preferably 60% by mass or more. The upper limit of the yield is not particularly limited, but is usually 100% by mass or less.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to the following Examples as long as the gist thereof is not exceeded. The present invention can adopt various conditions as long as the gist of the present invention is not deviated and the object of the present invention is achieved. The values of various manufacturing conditions and evaluation results in the following examples have meanings as preferable values of the upper limit or the lower limit in the embodiment of the present invention, and the preferable range is the above-mentioned upper limit or lower limit value. , The range specified by the combination of the values of the following examples or the values of the examples may be used.

In the following, all operations were performed in an argon, nitrogen or carbon dioxide atmosphere unless otherwise stated.
^{1 1} H-NMR spectrum was measured by a JEOL ECZ-500 and ECX-500 (500 MHz) spectrometer _{in CDCl 3 using residual CHCl 3} (for 1H, δ = 7.26) as an internal standard.
For thin layer chromatography (TLC) for analysis, a Merck silica gel 60 F254 plate (thickness 0.25 mm, ^{coated with 20 × 20 cm 2} glass) was used, and for preparative TLC, the thickness was 0 on the glass. Wakogel B-5F coated with .9 mm was used.
Visible light irradiation was performed using a Relyon Twin LED Light (3 W × 2, λ _irr. = 425 ± 15 nm) for photocatalytic reaction.

_{Et 2} O was dried by passing a column of activated alumina (A-2, Purity) followed by a column of Q-5 scavenger (Engelhard).
Dehydrated acetone, acetonitrile (MeCN), dimethylacetamide (DMA), dimethylformamide (DMF) and methanol (MeOH) were purchased from Kanto Chemical Co., Inc., and N-methylpyrrolidone (NMP) was purchased from Sigma Aldrich, Inc. before use. It was whipped with argon and degassed.
The tertiary amine compound was distilled, degassed by the freeze degassing method (3 times), and stored in a nitrogen atmosphere.
CO ₂ gas was purchased from Taiyo Nippon Sanso.

Pd (OAc) ₂ , XPhos, tBuXPhos, bromobenzene (Compound 1b), acetylbromobenzene (Compound 1r) and methyl 3-chlorobenzoate (Compound 6u) were purchased from Sigma Aldrich.

3,4-Methylenedioxybromobenzene (Compound 1a), 4-bromotoluene (Compound 1c), 4-bromoanisole (Compound 1d), 4-trifluoromethylbromobenzene (Compound 1e), 4-Fluorobromobenzene (Compound 1e) Compound 1f), 4-chlorobromobenzene (Compound 1 g), methyl 4-bromobenzoate (Compound 1i), 4-cyanobromobenzene (Compound 1j), 2-bromotoluene (Compound 1 m), 2,4,6- Triisopropylbromobenzene (Compound 1n), 3-bromothiophene (Compound 1o), chlorobenzene (Compound 6b), 4-chlorotoluene (Compound 6c), 4-trifluoromethylchlorobenzene (Compound 6e), 4-cyanochlorobenzene (Compound 6e). 6j), 4-Acetylchlorobenzene (Compound 6s), 3-chloroanisole (Compound 6t) and 2-chloronaphthalene (Compound 6v) were purchased from Tokyo Kasei Kogyo Co., Ltd.

Cesium carbonate and N-tert-butoxycarbonylbromoindole (Compound 1p) were purchased from Wako Pure Chemical Industries, Ltd.

PhXPhos, Ru (bpy) ₃ (PF ₆ ) ₂ , Ir (dF (CF ₃ ) ppy) ₂ (dtbbpy) (PF ₆ ), Ir (ppy) ₂ (dtbbpy) (PF ₆ ), Ir (ppy) ₂ ( dmobpy) (PF ₆ ), Ir (ppy) ₂ (Me ₄ phen) (PF ₆ ), TMSCHN ₂ , t-butoxycarbonylaminobromobenzene (Compound 1h), 4-triisopropylsilylethynylbromobenzene (Compound 1k), 4-Isopropenylbromobenzene (Compound 1l), 5-bromoindole (Compound 1q), and 4-chloroanisole (Compound 6d) were prepared by a conventionally known method.

Compounds 1a to 1f, 1m, 1o, 1r and 6b to 6e, 6s to 6u, which are liquid materials, were stored in an argon atmosphere after distillation.

(Example 1)
_{Ir (ppy) 2} (dtbbpy) (PF ₆ ) (0.002 mmol, 1.0 mol%) was used as the photooxidation-reduction catalyst component (A). Further, palladium acetate (1.1 mg, 0.005 mmol, 2.5 mol%) was used as a catalyst precursor for obtaining the transition metal catalyst component (B), and the organophosphorus compound (0.01 mmol, 0.01 mmol, shown in Table 1) shown in Table 1 was used as the ligand. 5.0 mol%) was used. In addition, N, N-diisopropylethylamine (iPr ₂ NEt, 0.10 mL, 0.60 mmol, 3.0 eq) was used as the tertiary amine compound. Furthermore, cesium carbonate (Cs ₂ CO ₃ , 195 mg, 0.60 mmol, 3.0 eq) was used as the basic compound.
N of 3,4-methylenedioxybromobenzene (compound 1a, 24 μL, 0.20 mmol) containing the photooxidation-reduction catalyst component (A), transition metal catalyst component (B), tertiary amine compound and basic compound. , N-Dimethylacetamide (DMA) solution (1.0 mL) was prepared in vitro under a nitrogen atmosphere. Note that contain a ^{1 H-NMR} spectrum of the previously prepared transition metal catalyst component (B), was compared with the ^{1 H-NMR} spectrum of the sample in the test tube, the transition metal catalyst component into a test tube (B) is I was able to confirm that it was.

The gas phase was then _{replaced with atmospheric pressure CO 2} and the reaction vessel was placed in a water bath at a distance of 10 mm from the light source. Then, using a blue LED lamp having two sockets, visible light (λ _irr. = 425 nm) was irradiated in a closed system at room temperature (specifically, 25 ° C.) for 6 hours. After irradiation with visible light, _{the reaction was suppressed using H 2} O, and the mixture in the reaction vessel was _{extracted with Et 2} O (diethyl ether) three times.

After washing the organic layer with H _{2 O, Na 2} SO ₄ was added and dehydrated. After filtering, the filtrate was concentrated to obtain a composition. The composition was ^{spectroscopically analyzed using 1} H-NMR, and the recovery rate of the starting material 3,4-methylenedioxybromobenzene (Compound 1a) and the yield of the hydrogenation product (Compound 3a) were measured (. Internal standard: dibromomethane).
Further, the aqueous layer was acidified with aqueous 1N HCl, then three times extracted work by _Et 2 O (diethyl ether). The organic layer was _{dehydrated and filtered through Na 2} SO ₄ and concentrated under reduced pressure to obtain an aromatic carboxylic acid (Compound 2a). The yield of the aromatic carboxylic acid (Compound 2a) ^{was measured by 1} H-NMR (internal standard: 1,4-dioxane).
The conversion rate of compound 1a was calculated from the amount of compound 1a initially blended and the recovery rate of compound 1a. The results are shown in Table 1.

(Examples 2 to 6)
In Example 1, the same operation as in Example 1 was performed except that the ligand was changed to that shown in Table 1. In Example 6, the same operation as in Example 4 was performed except that the component (A) was adjusted to 2.5 mol%. The results obtained are shown in Table 1.

From Table 1, it was shown that various organophosphorus compounds can be used as the ligand for producing the transition metal catalyst component (B). Further, from Example 6, when the content ratio of the photooxidation-reduction catalyst component (A) is increased, the yield of the aromatic carboxylic acid (Compound 2a) increases, and the yield of the hydrogenation product (Compound 3a) decreases. You can see that.

(Example 7)
The same operation as in Example 1 was performed except that the basic compound was not used in Example 1. The results are shown in Table 2.
(Comparative Examples 1 to 5)
The same operation as in Example 7 was performed except that the compounding components, the presence / absence of light irradiation, and the gas phase were changed as shown in Table 2 below (Comparative Examples 1 to 5). The results are shown in Table 2.

From Table 2, in order to obtain an aromatic carboxylic acid (Compound 2a) from an aromatic halogen compound, a photooxidation-reduction catalyst component (A), a transition metal catalyst component (B), carbon dioxide and light irradiation are indispensable. I understand. It was shown that the absence of one of these does not yield an aromatic carboxylic acid (Compound 2a).

(Examples 8 to 25)
As the aromatic bromide, compounds 1a to 1r were used in Examples 8 to 25, respectively. _{Compounds 1a to 1r are compounds in which the carboxylic acid ester moiety (-CO 2} Me) of the aromatic carboxylic acid methyl ester (compounds 5a to 5r in Table 3 below) is replaced with bromine (-Br).
_{Ir (ppy) 2} (dtbbpy) (PF ₆ ) (4.6 mg, 0.005 mmol, 2.5 mol%) was used as the photooxidation-reduction catalyst component (A). In addition, palladium acetate (1.1 mg, 0.005 mmol, 2.5 mol%) was used as a catalyst precursor for obtaining the transition metal catalyst component (B), and PhXPhos (0.01 mmol, 5.0 mol%) was used as a ligand. .. In addition, iPr ₂ NEt (0.10 mL, 0.60 mmol, 3.0 eq) was used as the tertiary amine compound. In addition, Cs ₂ CO ₃ (195 mg, 0.60 mmol, 3.0 eq) was used as the basic compound.
DMA solution (1.0) of aromatic bromide (0.20 mmol, compounds 1a to 1r in Table 3) containing the photooxidation-reduction catalyst component (A), transition metal catalyst component (B), tertiary amine compound and basic compound. mL) was prepared in vitro under a nitrogen atmosphere. Note that contain a ^{1 H-NMR} spectrum of the previously prepared transition metal catalyst component (B), was compared with the ^{1 H-NMR} spectrum of the sample in the test tube, the transition metal catalyst component into a test tube (B) is I was able to confirm that it was.

The gas phase was then _{replaced with atmospheric pressure CO 2} and the reaction vessel was placed in a water bath at a distance of 10 mm from the light source. Then, using a blue LED lamp having two sockets, visible light (λ _irr. = 425 nm) was irradiated in a closed system at room temperature (specifically, 25 ° C.) for 6 hours. After irradiation with visible light, _{the reaction was suppressed using H 2} O, and the mixture in the reaction vessel was _{extracted with Et 2} O (diethyl ether) three times.

The organic layer was washed with _{H 2} O. The aqueous layer was acidified with aqueous 1N HCl, then three times extracted work by _Et 2 O (diethyl ether). The organic layer was _{dehydrated and filtered through Na 2} SO ₄ and concentrated under reduced pressure to obtain an aromatic carboxylic acid. This aromatic carboxylic acid was dissolved in Et ₂ O (2.0 mL) and MeOH (methanol, 0.5 mL), and a solution of trimethylsilyldiazomethane (TMSCHN ₂ , 2.0 eq) in Et ₂ O was added at 0 ° C. The mixture was stirred at 0 ° C. for 30 minutes and the solvent was removed under reduced pressure to give the composition. The obtained composition was purified by preparative thin layer chromatography, and the methyl ester corresponding to the aromatic carboxylic acid (aromatic carboxylic acid methyl ester, in Examples 8 to 25, each of the compounds 5a to 5a in Table 3). 5r) was obtained. The yield of aromatic carboxylic acid methyl ester is shown in Table 3. ^{The yield was measured in 1 1} H-NMR spectrum by the same operation as in Example 1.
In Example 14, the visible light irradiation time was set to 4 hours, and in Example 21, the visible light irradiation time was set to 8 hours. Further, in Examples 15 to 17, 25, tBuXPhos was used instead of PhXPhos.

The "reaction time" in Table 3 means the visible light irradiation time. The results are shown in Table 3.

From Table 3, it was shown that aromatic bromides having various functional groups R can be used as starting materials. Specifically, when an aromatic bromide (compound 1c to 1 g, 1 k, 1 l) having an alkyl group, an alkoxy group, a halogen atom, an internal alkyne or an alkene at the 4-position is used as the functional group R, trimethylsilyldiazomethane (TMSCHN _{2) is used.} ), The yield of the aromatic carboxylic acid methyl ester obtained by the methyl esterification exceeded 80%, and good results were obtained.
In particular, when 4-chlorobromobenzene (1 g of the compound) was used as the substrate (starting material), 4-chlorobenzoate (5 g of the compound) was selectively obtained even though the reaction time was short.

Although the carboxylation reaction of aryltriflate having steric hindrance by cobalt and nickel catalysts is known, carboxylic acid was not obtained from 2,6-diisopropylphenyltriflate in this carboxylation reaction. On the other hand, the carboxylation reaction of 2,4,6-triisopropylbromobenzene (compound 1n) having the same steric hindrance was carried out by the combined use of the photooxidation-reduction catalyst component (A) and the transition metal catalyst component (B) 76. Progressed in% yield. This indicates that it can also be used for bulky substrates.

Methyl esters (compounds 5o-5q) were also obtained from electron-rich heteroarene bromides such as thiophene (compound 1o) and indole (compound 1p, 1q).

(Examples 26 to 34)
The same operations as in Examples 8 to 25 were carried out except that aromatic chloride was used instead of the aromatic bromide and tBuXPhos was used as a ligand for obtaining the transition metal catalyst component (B).

Specifically, as the aromatic chloride, compounds 6b to 6e, 6j, and 6s to 6v were used in Examples 26 to 34, respectively. _{In compounds 6b to 6e, 6j, 6s to 6v, the carboxylic acid ester moiety (-CO 2} Me) of the aromatic carboxylic acid methyl ester (compounds 5b to 5e, 5j, 5s to 5v in Table 4 below) is chlorine (-CO 2 Me). It is a compound substituted with Cl).
_{Ir (ppy) 2} (dtbbpy) (PF ₆ ) (4.6 mg, 0.005 mmol, 2.5 mol%) was used as the photooxidation-reduction catalyst component (A). In addition, palladium acetate (1.1 mg, 0.005 mmol, 2.5 mol%) was used as a catalyst precursor for obtaining the transition metal catalyst component (B), and tBuXPhos (0.01 mmol, 5.0 mol%) was used as a ligand. .. In addition, iPr ₂ NEt (0.10 mL, 0.60 mmol, 3.0 eq) was used as the tertiary amine compound. In addition, Cs ₂ CO ₃ (195 mg, 0.60 mmol, 3.0 eq) was used as the basic compound.
Aromatic chloride (0.20 mmol, compounds 6b to 6e, 6j, 6s ~ in Table 4, containing the photooxidation-reduction catalyst component (A), transition metal catalyst component (B), tertiary amine compound and basic compound. A DMA solution (1.0 mL) of 6v) was prepared in vitro under a nitrogen atmosphere. Note that contain a ^{1 H-NMR} spectrum of the previously prepared transition metal catalyst component (B), was compared with the ^{1 H-NMR} spectrum of the sample in the test tube, the transition metal catalyst component into a test tube (B) is I was able to confirm that it was.

The gas phase was then _{replaced with atmospheric pressure CO 2} and the reaction vessel was placed in a water bath at a distance of 10 mm from the light source. Then, using a blue LED lamp having two sockets, visible light (λ _irr. = 425 nm) was irradiated in a closed system at room temperature (specifically, 25 ° C.) for 6 hours. After irradiation with visible light, _{the reaction was suppressed using H 2} O, and the mixture in the reaction vessel was _{extracted with Et 2} O (diethyl ether) three times.

The organic layer was washed with _{H 2} O. The aqueous layer was acidified with aqueous 1N HCl, then three times extracted work by _Et 2 O (diethyl ether). The organic layer was _{dehydrated and filtered through Na 2} SO ₄ and concentrated under reduced pressure to obtain an aromatic carboxylic acid. This aromatic carboxylic acid was dissolved in Et ₂ O (2.0 mL) and MeOH (methanol, 0.5 mL), and a solution of trimethylsilyldiazomethane (TMSCHN ₂ , 2.0 eq) in Et ₂ O was added at 0 ° C. The mixture was stirred at 0 ° C. for 30 minutes and the solvent was removed under reduced pressure to give the composition. The obtained composition was purified by preparative thin layer chromatography, and the methyl ester corresponding to the aromatic carboxylic acid (aromatic carboxylic acid methyl ester, in Examples 26 to 34, compounds 5b to 4 in Table 4, respectively. 5e, 5j, 5s-5v) were obtained. The yield of aromatic carboxylic acid methyl ester is shown in Table 4. ^{The yield was measured in 1 1} H-NMR spectrum by the same operation as in Example 1.

From Table 4, it was shown that various aromatic carboxylic acid methyl esters can be obtained in good yields from various aromatic chlorides by methyl esterification using _{TMSCHN 2.}

In _{the Pd-catalyzed carboxylation reaction using ZnEt 2} , the aromatic carboxylic acid could not be obtained from the aromatic chloride, which is cheaper than the bromine. On the other hand, in the carboxylation reaction using a catalyst composition containing a photooxidation-reduction catalyst component (A) and a transition metal catalyst component (B), a wide variety of substrates can be used, and aromatics having various functional groups can be used. Aromatic carboxylic acids or esters thereof were obtained from chlorides in good yields and were found to be very useful.

(Examples 35 to 36)
Using the photooxidation-reduction catalyst component (A) shown in Table 5 below, the content ratio of the tertiary amine compound was 6.0 equivalent to the halogen atom in the aromatic halogen compound, and the basic compound was used. The same operation as in Example 1 was performed except that there was no such thing. The results are shown in Table 5.

_{From Table 5, when Ir (ppy) 2} (dmobpy) (PF ₆ ), which has a higher reducing power than _{Ir (ppy) 2} (Me ₄ phen) (PF ₆ ), is used as the photooxidation-reduction catalyst component (A), the substrate is used. It can be seen that the conversion rate of (Compound 1a) and the yield of the aromatic carboxylic acid (Compound 2a) are excellent.

(Examples 37 to 38)
In Example 37, the content ratio of the tertiary amine compound was 6.0 equivalents, and the same operation as in Example 1 was carried out except that the basic compound was not used.
Further, as Example 38, the same operation as in Example 37 was performed except that the content ratio of the photooxidation-reduction catalyst component (A) was changed to 2.5 mol%. The results are shown in Table 6.

From Table 6, it can be seen that the target compound can be obtained in good yield without using a basic compound. Further, it can be seen that by increasing the content ratio of the photooxidation-reduction catalyst component (A), the production of the hydrogenation product (Compound 3a) is suppressed and the yield of the aromatic carboxylic acid (Compound 2a) is improved.

(Examples 39 to 40)
The same as in Example 1 except that the photooxidation-reduction catalyst component (A) shown in Table 7 below was used, the content ratio of the tertiary amine compound was 6.0 equivalents, and no basic compound was used. The operation was performed. The results are shown in Table 7.

From Table 7, it was shown that an aromatic carboxylic acid can be produced from an aromatic halogen compound even when _{Ru (bpy) 3} (PF ₆ ) ₂ is used as the photooxidation-reduction catalyst component (A). Also, since the reducing power of Ir (dF (CF ₃ ) ppy) ₂ (dtbbpy) (PF ₆ ) is superior to the reducing power of Ru (bpy) ₃ (PF ₆ ) ₂ , photooxidation containing an appropriate transition metal It can be seen that the yield of the aromatic carboxylic acid is improved by selecting the reduction catalyst component (A).

The catalyst composition according to the present invention does not use a metal reducing agent containing a transition metal element such as Zn or Mn (transition metal element belonging to Group 7 or Group 12 of the Periodic Table), and carbon dioxide is used under light irradiation conditions. Since the aromatic carboxylic acid or an ester thereof can be produced from the above and the aromatic halogen compound, the environmental load can be reduced.

Claims (5)

A photooxidation-reduction catalyst component (A) containing a transition metal M belonging to groups 8 to 10 of the periodic table and a transition metal catalyst component (B) containing a transition metal M'belonging to groups 8 to 11 of the periodic table and different from the transition metal M. ) And
A catalyst composition for producing an aromatic carboxylic acid or an ester thereof from carbon dioxide and an aromatic halogen compound under light irradiation conditions .
The photooxidation-reduction catalyst component (A) is a compound represented by the general formula (1).
(NC) _3-x (NN) _x M (1)
(N in the general formula (1) represents a nitrogen atom, C represents a carbon atom, and NC represents a bidentate ligand that coordinates the transition metal M with the nitrogen atom and the carbon atom. , N—N represent a bidentate ligand coordinated to the transition metal M with a nitrogen atom and a nitrogen atom, the bidentate ligand of (NC) has a phenylpyridine skeleton, and (N). The bidentate ligand of −N) has a bipyridine skeleton or a phenanthroline skeleton. In addition, x represents an integer of 0 to 3. The transition metal M is iridium or ruthenium.)
The catalyst composition in which the transition metal catalyst component (B) is such that the transition metal M'is palladium and contains an organophosphorus compound as a ligand. A photooxidation-reduction catalyst component (A) containing a transition metal M belonging to groups 8 to 10 of the periodic table and a transition metal catalyst component (B) containing a transition metal M'belonging to groups 8 to 11 of the periodic table and different from the transition metal M. ) and the presence of a catalyst composition comprising, viewed including the step of light irradiation to carbon dioxide and aromatic halogen compounds,
The photooxidation-reduction catalyst component (A) is a compound represented by the general formula (1).
(NC) _3-x (NN) _x M (1)
(N in the general formula (1) represents a nitrogen atom, C represents a carbon atom, and NC represents a bidentate ligand that coordinates the transition metal M with the nitrogen atom and the carbon atom. , N—N represent a bidentate ligand coordinated to the transition metal M with a nitrogen atom and a nitrogen atom, the bidentate ligand of (NC) has a phenylpyridine skeleton, and (N). The bidentate ligand of −N) has a bipyridine skeleton or a phenanthroline skeleton. In addition, x represents an integer of 0 to 3. The transition metal M is iridium or ruthenium.)
A method for producing an aromatic carboxylic acid or an ester thereof, wherein the transition metal catalyst component (B) contains palladium as the transition metal M'and an organophosphorus compound as a ligand. The method for producing an aromatic carboxylic acid or an ester thereof according to claim 2 , wherein the aromatic halogen compound is an aromatic chloride, an aromatic bromide or an aromatic iodine product. The method for producing an aromatic carboxylic acid or an ester thereof according to claim 2 or 3 , wherein a tertiary amine compound is present together with the catalyst composition. The method for producing an aromatic carboxylic acid or an ester thereof according to any one of claims 2 to 4 , wherein a basic compound is present together with the catalyst composition.