Catalyst for cyclic carbonate synthesis reaction and method for producing cyclic carbonate

Abstract

To provide a catalyst for a cyclic carbonate synthesis reaction which exhibits very high activity in the reaction of yielding a cyclic carbonate from an epoxide and carbon dioxide, without using rare metals such as chromium or cobalt, and a method for producing a cyclic carbonate using the catalyst.SOLUTION: The present invention provides a catalyst for a cyclic carbonate synthesis reaction comprising a metal complex, and a method for producing a cyclic carbonate, wherein the method includes using the metal complex as a catalyst in a reaction in which an epoxide and carbon dioxide are reacted to synthesize a cyclic carbonate.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a catalyst for a cyclic carbonate synthesis reaction and a method for producing a cyclic carbonate. [Background technology]

[0002] Cyclic carbonates are important chemicals in the production of many materials in the polymer industry, as they are used as precursors in the production of polycarbonates and polyurethanes. Cyclic carbonates are also the main raw materials for the electrolyte of lithium-ion batteries, which are widely used in portable electronics and electric vehicles, due to their high dielectric constant and good lithium coordination ability. Therefore, there is a growing demand for cyclic carbonates around the world.

[0003] A typical method for producing cyclic carbonates has been to use a method using phosgene. However, from the viewpoint of toxicity and environmental load, a method for synthesizing cyclic carbonates without using phosgene is desired. Among them, the synthesis of cyclic carbonates by the reaction of epoxides with carbon dioxide is attracting attention as a method for synthesizing cyclic carbonates without using phosgene, since carbon dioxide is used as a raw material, which is non-toxic, abundant in nature, and desirable for effective use.

[0004] As a catalyst for promoting the above-mentioned cyclic carbonate synthesis reaction, catalysts using chromium complexes, cobalt complexes, etc. have been reported so far (for example, Non-Patent Document 1). However, chromium and cobalt are rare metals, so they are expensive and the amount of resources is limited.

[0005] In addition, Non-Patent Document 2 describes the synthesis of cyclic carbonates using aluminum phthalocyanine as a catalyst. However, the catalyst described in Non-Patent Document 1 may not have sufficient activity, and a catalyst having better catalytic ability for the cyclic carbonate synthesis reaction has been desired.

[0006] Therefore, there has been a demand for the development of a catalyst that uses inexpensive materials that are abundant in resources and does not use rare metals, and that has high catalytic activity for the cyclic carbonate synthesis reaction. [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] MT Nazeri, et al., Journal of Taiwan Institute of Chemical Engineers 136 (2022), 104428 [Non-Patent Document 2] D. Ji, et al., Applied Catalysis A: General 203 (2000), pp. 329-333 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made to solve the problems of the conventional technology described above, and aims to provide a catalyst for cyclic carbonate synthesis reaction that has extremely high activity in the reaction of synthesizing cyclic carbonate by reacting epoxide with carbon dioxide and does not use rare metals, and a method for producing cyclic carbonate using the catalyst. [Means for solving the problem]

[0009] As a result of extensive investigations into the above-mentioned problems, the present inventors unexpectedly discovered that a metal complex having a specific chemical structure has excellent catalytic activity for a cyclic carbonate synthesis reaction, and thus arrived at the present invention.

[0010] The object of the present invention is to provide a compound of formula (I): [ka] (In the formula, M is an iron atom or an aluminum atom; E1 to E8 each independently represent a carbon atom or a nitrogen atom, and when E1 to E8 each independently represent a carbon atom, the carbon atom each independently represents a hydrogen atom, a halogen atom, or an alkyl group bonded thereto; R1 to R8 are each independently a hydrogen atom, an alkyl group, or an R-SO2 group; In the R-SO group, R is an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, an alkenyloxy group, an acyl group, or an acyloxy group; however, At least one of R1 or R2 is an R-SO2 group; At least one of R3 or R4 is an R-SO2 group; At least one of R5 or R6 is an R-SO2 group; At least one of R7 or R8 is an R-SO2 group. This is achieved by a catalyst for a cyclic carbonate synthesis reaction, which comprises a metal complex of the formula:

[0011] In the formula (I), it is preferred that R1, R3, R5 and R7 are R-SO2 groups, and R2, R4, R6 and R8 are hydrogen atoms.

[0012] In the R-SO2 group, it is preferred that the R group is an alkyl group.

[0013] The alkyl group of the R group is preferably a branched alkyl group having 3 to 12 carbon atoms.

[0014] The alkyl group of the R group is preferably 2-ethylhexyl.

[0015] In the above formula (I), M is preferably an iron atom.

[0016] In the formula (I), E1 to E8 are preferably carbon atoms bonded to a hydrogen atom.

[0017] The metal complex has the formula: [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] It is preferable that the formula is represented by the formula:

[0018] The present invention also relates to a method for producing a cyclic carbonate, which comprises using the metal complex of formula (I) as a catalyst in the reaction of an epoxide with carbon dioxide to synthesize the cyclic carbonate. Effect of the Invention

[0019] According to the present invention, a metal complex having a specific structure is used as a catalyst for the reaction of an epoxide with carbon dioxide to synthesize a cyclic carbonate, thereby making it possible to proceed with the cyclic carbonate synthesis reaction with high efficiency.

[0020] Furthermore, since the present invention does not use rare metals, it is possible to provide a relatively inexpensive and highly active catalyst for the synthesis reaction of cyclic carbonates without being restricted by resource supplies. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Hereinafter, a mode for carrying out the present invention (hereinafter, simply referred to as "embodiment") will be described in detail. The embodiment is an example for explaining the present invention, and the present invention is not limited to the embodiment. In other words, the present invention can be modified in various ways without departing from the gist of the present invention.

[0022] [Catalyst for cyclic carbonate synthesis reaction] The present invention relates to a catalyst for a cyclic carbonate synthesis reaction, which comprises a metal complex having a specific chemical structure.

[0023] The catalyst for cyclic carbonate synthesis reaction of the present invention is a catalyst that promotes the reaction of synthesizing cyclic carbonate by reacting epoxide with carbon dioxide. The catalyst for cyclic carbonate synthesis reaction of the present invention does not use rare metals, and further has a very excellent activity, for example, a high catalyst turnover frequency (the amount of epoxide compound converted to polymer per unit mole of metal in the catalyst per unit time), compared with catalysts using conventional metal complexes.

[0024] <Metal complex> The catalyst of the present invention comprises a metal complex of formula (I). [ka] (In the formula, M is an iron atom or an aluminum atom; E1 to E8 each independently represent a carbon atom or a nitrogen atom, and when E1 to E8 each independently represent a carbon atom, the carbon atom each independently represents a hydrogen atom, a halogen atom, or an alkyl group bonded thereto; R1 to R8 are each independently a hydrogen atom, an alkyl group, or an R-SO2 group; In the R-SO group, R is an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, an alkenyloxy group, an acyl group, or an acyloxy group; however, At least one of R1 or R2 is an R-SO2 group; At least one of R3 or R4 is an R-SO2 group; At least one of R5 or R6 is an R-SO2 group; At least one of R7 or R8 is an R-SO2 group.

[0025] In formula (I), M is an iron atom or an aluminum atom. Iron and aluminum are abundant on earth and are inexpensive metal elements, so that a catalyst for a cyclic carbonate synthesis reaction can be obtained economically without being restricted by resource supply. In one embodiment, M is preferably an iron atom. When M is an iron atom, a catalyst for a cyclic carbonate synthesis reaction having higher activity can be obtained.

[0026] In formula (I), the bond between the nitrogen atom and M means the coordination of the nitrogen atom to M. The valence of M is not particularly limited. A ligand may be further bonded to M so that the metal complex is electrically neutral. Examples of the ligand include a halogen atom, a hydroxyl group, or a hydrocarbon group having 1 to 8 carbon atoms. An anionic counter ion may be present so that the metal complex is electrically neutral. Examples of the anionic counter ion include a halide ion, a hydroxide ion, a nitrate ion, and a sulfate ion. In one embodiment, it is preferable that a ligand is bonded to M, it is more preferable that a halogen atom is bonded to M as a ligand, it is even more preferable that a fluorine atom or a chlorine atom is bonded to M as a ligand, and it is particularly preferable that a chlorine atom is bonded to M as a ligand.

[0027] In formula (I), E1 to E8 are each independently a carbon atom or a nitrogen atom, and when E1 to E8 are carbon atoms, the carbon atoms are each independently bonded to a hydrogen atom, a halogen atom, or an alkyl group. In one embodiment, E1, E3, E5, and E7 are preferably hydrogen atoms, halogen atoms, or carbon atoms bonded to an alkyl group, particularly hydrogen atoms, and E2, E4, E6, and E8 are preferably nitrogen atoms. In another embodiment, E1, E3, E5, and E7 are preferably hydrogen atoms, halogen atoms, or carbon atoms bonded to an alkyl group, particularly hydrogen atoms, and E2, E4, E6, and E8 are preferably hydrogen atoms, halogen atoms, or carbon atoms bonded to an alkyl group, particularly hydrogen atoms, and E2, E4, E6, and E8 are preferably hydrogen atoms, halogen atoms, or carbon atoms bonded to an alkyl group, particularly hydrogen atoms.

[0028] In formula (I), R1 to R8 are each independently a hydrogen atom, an alkyl group, or an R-SO2 group, provided that at least one of R1 or R2 is an R-SO2 group, at least one of R3 or R4 is an R-SO2 group, at least one of R5 or R6 is an R-SO2 group, and at least one of R7 or R8 is an R-SO2 group. That is, the metal complex of formula (I) of the present invention has 4 to 8 R-SO2 groups. In one embodiment, the metal complex of formula (I) of the present invention preferably has 4 or 8 R-SO2 groups, and particularly preferably has 4 R-SO2 groups. By the metal complex of formula (I) having the above-mentioned number of R-SO2 groups, the catalyst of the present invention can have very excellent catalytic activity.

[0029] In formula (I), it is particularly preferred that R1, R3, R5 and R7 are R-SO2 groups, and R2, R4, R6 and R8 are hydrogen atoms. By having the above-mentioned structure of the metal complex, the catalyst of the present invention can have very excellent catalytic activity.

[0030] In the R-SO2 group, the R group is an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, an alkenyloxy group, an acyl group, or an acyloxy group.

[0031] In the present invention, the alkyl group refers to a linear or branched monovalent hydrocarbon group. The number of carbon atoms in the alkyl group is preferably 1 to 20, more preferably 2 to 12, and even more preferably 4 to 8. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, a hexyl group, a 1-ethylbutyl group, a 2-ethylbutyl group, a 3-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, a 4-methylpentyl group, a heptyl group, a 1-methylhexyl group, a 2-methylhexyl group, a 3-methylhexyl group, a 4-methylpentyl group, a 5-methylhexyl group, a 6-methylhexyl group, a 7-methylhexyl group, a 8-methylhexyl group, a 9-methylhexyl group, a 10-methylhexyl group, a 11-methylhexyl group, a 12-methylhexyl group, a 13-methylhexyl group, a 14-methylhexyl group, a 15-methylhexyl group, a 16-methylhexyl group, a 17-methylhexyl group, a 18-methylhexyl group, a 21-methylhexyl group, a 22-methylhexyl group, a 23-methylhexyl group, a 24-methylhexyl group, a 25-methylhexyl group, a 26-methylhexyl group, a 27-methylhexyl group, a 28-methylhexyl group, a 29-methylhexyl group, a 30-methylhexyl group, a 31-methylhexyl group, a 32-methylhexyl group, a 33- ethylhexyl group, 4-methylhexyl group, 5-methylhexyl group, 1-ethylpentyl group, 2-ethylpentyl group, 3-ethylpentyl group, 4-ethylpentyl group, 1,1-dimethylpentyl group, 2,2-dimethylpentyl group, 3,3-dimethylpentyl group, 4,4-dimethylpentyl group, 5,5-dimethylpentyl group, 1,2-dimethylpentyl group, 1,3-dimethylpentyl group, 1,4-dimethylpentyl group, 1,5-dimethylpentyl group, 2,3-dimethylpentyl group, 2,4-dimethylpentyl group, Methylpentyl, 2,5-dimethylpentyl, 3,4-dimethylpentyl, 3,5-dimethylpentyl, 4,5-dimethylpentyl, octyl, 1-methylheptyl, 2-methylheptyl, 3-methylheptyl, 4-methylheptyl, 5-methylheptyl, 6-methylheptyl, 1-ethylhexyl, 2-ethylhexyl, 3-ethylhexyl, 4-ethylhexyl, 5-ethylhexyl, 1-ethylheptyl, 2-ethylheptyl, 3-ethyl heptyl group, 4-ethylheptyl group, 5-ethylheptyl group, 6-ethylheptyl group, 1-methyloctyl group, 2-methyloctyl group, 3-methyloctyl group, 4-methyloctyl group, 5-methyloctyl group, 6-methyloctyl group, 7-methyloctyl group, 1-ethyloctyl group, 2-ethyloctyl group, 3-ethyloctyl group, 4-ethyloctyl group, 5-ethyloctyl group, 6-ethyloctyl group, 7-ethyloctyl group, 3-n-propylheptyl group, nonyl group, decyl group, 3,Examples include 7-dimethyloctyl, 2-n-hexyl-decyl, and groups in which the hydrogen atoms in these groups are substituted with substituents such as halogen, alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, cyano groups, carbonyl groups, ester groups, amino groups, nitro groups, silyl groups, and sulfo groups.

[0032] In the present invention, the alkenyl group refers to a linear or branched monovalent hydrocarbon group containing a double bond. The number of carbon atoms in the alkenyl group is preferably 2 to 20, more preferably 3 to 12, and further preferably 4 to 8. Examples of alkenyl groups include vinyl groups, 1-propenyl groups, 2-propenyl groups, 1-butenyl groups, 2-butenyl groups, 3-butenyl groups, 1-methyl-2-propenyl groups, 2-methyl-2-propenyl groups, 1-pentenyl groups, 2-pentenyl groups, 3-pentenyl groups, 4-pentenyl groups, 1-methyl-2-butenyl groups, 2-methyl-2-butenyl groups, 3-methyl-2-butenyl groups, 1-hexenyl groups, 2-hexenyl groups, 3-hexenyl groups, 4-hexenyl groups, 5-hexenyl groups, 6-heptenyl groups, 7-octenyl groups, and groups in which hydrogen atoms in these groups are substituted with substituents such as halogens, alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, cyano groups, carbonyl groups, ester groups, amino groups, nitro groups, silyl groups, and sulfo groups.

[0033] In the present invention, the alkynyl group refers to a linear or branched monovalent hydrocarbon group containing a triple bond. The alkynyl group preferably has 2 to 20 carbon atoms, more preferably 3 to 12 carbon atoms, and further preferably 4 to 8 carbon atoms. Examples of alkynyl groups include ethynyl, 1-propynyl, 2-propynyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-methyl-2-propynyl, 2-methyl-3-butynyl, 1-pentynyl, 2-pentynyl, 3-pentynyl, 4-pentynyl, 1-methyl-2-butynyl, 2-methyl-3-pentynyl, 1-hexynyl, and 1,1-dimethyl-2-butynyl groups, as well as groups in which the hydrogen atoms in these groups are substituted with substituents such as halogen, alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, cyano groups, carbonyl groups, ester groups, amino groups, nitro groups, silyl groups, and sulfo groups.

[0034] In the present invention, the alkoxy group refers to a monovalent hydrocarbon group to which an alkyl group is bonded via an ether bond. The number of carbon atoms in the alkoxy group is preferably 1 to 20, more preferably 2 to 12, and even more preferably 4 to 8. Examples of the alkoxy group include a methoxy group, an ethoxy group, an n-propoxy group, an n-butoxy group, an n-pentyloxy group, an n-hexyloxy group, an isopropoxy group, an isobutoxy group, a sec-butoxy group, a tert-butoxy group, a hexyloxy group, an octyloxy group, and a decyloxy group, as well as groups in which the hydrogen atom in these groups is substituted with a substituent such as a halogen, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, a cyano group, a carbonyl group, an ester group, an amino group, a nitro group, a silyl group, and a sulfo group.

[0035] In the present invention, the alkenyloxy group refers to a monovalent hydrocarbon group to which an alkenyl group is bonded via an ether bond. The number of carbon atoms in the alkenyloxy group is preferably 1 to 20, more preferably 2 to 12, and even more preferably 4 to 8. Examples of the alkenyloxy group include a vinyloxy group, an allyloxy group, and groups in which the hydrogen atom in these groups is substituted with a substituent such as a halogen, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, a cyano group, a carbonyl group, an ester group, an amino group, a nitro group, a silyl group, and a sulfo group.

[0036] In the present invention, the acyl group refers to a monovalent hydrocarbon group obtained by removing a hydroxyl group from a carboxy group of a carboxylic acid. The number of carbon atoms in the acyl group is preferably 1 to 20, more preferably 2 to 12, and even more preferably 4 to 8. Examples of the acyl group include an acetyl group, a propionyl group, a butyryl group, an isobutyryl group, a valeryl group, a pivaloyl group, a hexanoyl group, a heptanoyl group, an octanoyl group, and a decanoyl group, and groups in which the hydrogen atom in these groups is substituted with a substituent such as a halogen, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, a cyano group, a carbonyl group, an ester group, an amino group, a nitro group, a silyl group, and a sulfo group.

[0037] In the present invention, the acyloxy group refers to a monovalent hydrocarbon group in which the acyl group is bonded to an oxygen atom. The number of carbon atoms in the acyloxy group is preferably 1 to 20, more preferably 2 to 12, and even more preferably 4 to 8. Examples of the acyloxy group include an acetoxy group, a propionyloxy group, and a butyryloxy group, as well as groups in which the hydrogen atom in these groups is substituted with a substituent such as a halogen, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, a cyano group, a carbonyl group, an ester group, an amino group, a nitro group, a silyl group, and a sulfo group.

[0038] In the present invention, the R group is preferably an alkyl group, an alkenyl group, or an alkynyl group, more preferably an alkyl group, more preferably an alkyl group having 1 to 20 carbon atoms, even more preferably an alkyl group having 2 to 15 carbon atoms, even more preferably an alkyl group having 3 to 10 carbon atoms, and particularly preferably an alkyl group having 4 to 8 carbon atoms.

[0039] In the present invention, the R group is preferably a branched alkyl group, more preferably a branched alkyl group having 3 to 20 carbon atoms, even more preferably a branched alkyl group having 4 to 15 carbon atoms, even more preferably a branched alkyl group having 4 to 10 carbon atoms, and particularly preferably a branched alkyl group having 4 to 8 carbon atoms.

[0040] In the present invention, R is an isobutyl group, a sec-butyl group, a tert-butyl group, a 1-methylbutyl group, a 2-methylbutyl group, a 3-methylbutyl group, a 1-ethylbutyl group, a 2-ethylbutyl group, a 3-ethylbutyl group, a 1-methylpentyl group, a 2-methylpentyl group, a 3-methylpentyl group, a 4-methylpentyl group, a 1-ethylpentyl group, a 2-ethylpentyl group, a 3-ethylpentyl group, a 4-ethylpentyl group, a 1-methylhexyl group, a xyl group, 2-methylhexyl group, 3-methylhexyl group, 4-methylhexyl group, 5-methylhexyl group, 1-ethylhexyl group, 2-ethylhexyl group, 3-ethylhexyl group, 4-ethylhexyl group, 5-ethylhexyl group, 2-ethylheptyl group, 2-ethyloctyl group, 3-n-propylheptyl group, propyl group substituted with an ester group, butyl group, pentyl group, or hexyl group, and propyl group substituted with an alkoxy group. , butyl group, pentyl group, or hexyl group, more preferably a group selected from the group consisting of 1-methylbutyl group, 2-methylbutyl group, 3-methylbutyl group, 1-ethylbutyl group, 2-ethylbutyl group, 3-ethylbutyl group, 1-methylhexyl group, 2-methylhexyl group, 3-methylhexyl group, 4-methylhexyl group, 5-methylhexyl group, 1-ethylhexyl group, 2-ethylhexyl group, 3-ethylhexyl group, 4-ethylhexyl group, 5-ethylhexyl group, 2-ethylheptyl group, 2-ethyloctyl group, and 3-n-propylheptyl group, even more preferably a group selected from the group consisting of 2-methylbutyl group, 2-ethylbutyl group, 2-methylpentyl group, 2-methylhexyl group, 2-ethylpentyl group, and 2-ethylhexyl group, and particularly preferably a 2-ethylhexyl group.

[0041] Preferably, the catalyst of the present invention comprises a metal complex represented by the formula: [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka] [ka]

[0042] In the catalyst for cyclic carbonate synthesis reaction of the present invention, the content of the metal complex of formula (I) is preferably 50 mass% or more, more preferably 75 mass% or more, even more preferably 90 mass% or more, particularly preferably 95 mass% or more, and most preferably 99 mass% or more, based on 100 mass% of the total amount of the catalyst. In one embodiment, the catalyst for cyclic carbonate synthesis reaction of the present invention is composed of the metal complex of formula (I).

[0043] In another embodiment, the catalyst for cyclic carbonate synthesis reaction of the present invention may include a metal complex of formula (I) and a carbon material or a metal oxide. The carbon material is not particularly limited, but is preferably selected from the group consisting of carbon nanotubes, graphite, amorphous carbon, activated carbon, graphene, carbon black, carbon fiber, mesocarbon microbeads, microcapsule carbon, fullerene, carbon nanofoam, and carbon nanohorn, more preferably selected from the group consisting of carbon nanotubes, carbon black, and graphene, and even more preferably carbon nanotubes. Examples of metal oxides include SiO2, TiO2, and the like.

[0044] <Metal Complex Manufacturing Method> The method for producing the metal complex of the formula (I) of the present invention is not particularly limited, but may be, for example, a method in which a dicyano compound such as pyridine-2,3-dicarbonitrile and a metal atom (iron or aluminum) are heated in an alcohol solvent in the presence of a basic substance. Examples of the basic substance include inorganic bases such as potassium carbonate, sodium carbonate, calcium carbonate, sodium hydrogencarbonate, and sodium acetate, and organic bases such as triethylamine, tributylamine, and diazabicycloundecene.

[0045] [Method of producing cyclic carbonates] In one embodiment, the present invention relates to a method for producing a cyclic carbonate, comprising using a metal complex of formula (I) as described above as a catalyst in the reaction of an epoxide with carbon dioxide to synthesize the cyclic carbonate.

[0046] In the present invention, the epoxide is represented by the following formula (1): [ka] (In the formula, A4 to A7 are each independently a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms. The monovalent organic group means a monovalent group having a carbon atom. A4 to A7 may be bonded to each other to form a ring). Examples of epoxides include ethylene oxide, propylene oxide, 1-butene oxide, 2-butene oxide, isobutylene oxide, 1-pentene oxide, 2-pentene oxide, 1-hexene oxide, 1-octene oxide, 1-decene oxide, cyclopentene oxide, cyclohexene oxide, styrene oxide, vinylcyclohexane oxide, 3-phenylpropylene oxide, 3,3,3-trifluoropropylene oxide, 3-naphthylpropylene oxide, 3-phenoxypropylene oxide, 3-naphthoxypropylene oxide, butadiene monoxide, 3-vinyloxypropylene oxide, and 3-trimethylsilyloxypropylene oxide. Among them, the epoxide is preferably ethylene oxide or propylene oxide, and more preferably propylene oxide. These epoxides may be used alone or in combination of two or more.

[0047] In the present invention, the cyclic carbonate is represented by the following formula (2): [ka] (wherein A4 to A7 are the same as in the above general formula (1)).

[0048] The method for synthesizing a cyclic carbonate by reacting an epoxide with carbon dioxide is not particularly limited, but an example thereof is a method in which the cyclic carbonate synthesis reaction catalyst of the present invention and an epoxide are added to a pressure vessel such as an autoclave, and then the pressure vessel is filled with carbon dioxide.

[0049] In the method of the present invention, the amount of the catalyst for cyclic carbonate synthesis reaction of the present invention used is not particularly limited, but it is preferably used in an amount of 0.001 to 1 mol % relative to the epoxide, more preferably 0.001 to 0.5 mol %, even more preferably 0.01 to 0.25 mol %, and particularly preferably 0.05 to 0.1 mol %.

[0050] The pressure of carbon dioxide used in the present invention is preferably 0.1 to 6.0 MPa, more preferably 0.2 to 5.0 MPa, even more preferably 0.5 to 3.0 MPa, and particularly preferably 1.0 to 2.0 MPa.

[0051] The reaction temperature is preferably from 20 to 200°C, more preferably from 50 to 180°C, even more preferably from 80 to 160°C, and particularly preferably from 100 to 140°C.

[0052] The reaction time is preferably from 0.1 to 12 hours, more preferably from 0.2 to 6 hours, more preferably from 0.3 to 3 hours, and particularly preferably from 0.5 to 2 hours.

[0053] According to the method of the present invention, even under the mild conditions as described above, a cyclic carbonate can be efficiently synthesized.

[0054] In one embodiment, the contacting of the catalyst of the present invention with the reaction system comprising carbon dioxide and an epoxide is operated under solvent-free conditions, hi another embodiment, the contacting of the catalyst of the present invention with the reaction system comprising carbon dioxide and an epoxide is carried out in the presence of an organic solvent selected from dichloromethane, hexane, benzene, toluene, dimethylformamide or mixtures thereof.

[0055] In the method of the present invention, in addition to the catalyst of the present invention, an additive may be further used. An example of the additive is a promoter.

[0056] In the method of the present invention, the co-catalyst is not particularly limited, but examples thereof include imidazolium chloride, imidazolium bromide, imidazolium iodide, bis(triphenylphosphine)iminium chloride, bis(triphenylphosphine)iminium bromide, bis(triphenylphosphine)iminium iodide, 4-dimethylaminopyridine, tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium iodide, and mixtures thereof. Among them, the co-catalyst is preferably bis(triphenylphosphine)iminium chloride, bis(triphenylphosphine)iminium bromide, or bis(triphenylphosphine)iminium iodide, and more preferably bis(triphenylphosphine)iminium chloride.

[0057] In the method of the present invention, the amount of the co-catalyst used is not particularly limited, but is preferably 0.0001 to 1 mol % relative to the epoxide, more preferably 0.001 to 0.5 mol %, even more preferably 0.01 to 0.25 mol %, and particularly preferably 0.05 to 0.1 mol %. EXAMPLES

[0058] The present invention will be described in more detail below using examples and comparative examples, but the scope of the present invention is not limited to the examples.

[0059] [Synthesis of metal complexes] Synthesis Example 1: Synthesis of metal complex 8 Metal complex 8 was synthesized via the following route. [ka]

[0060] Synthesis Example 1-1 Synthesis of compound (2) 250 mL of methanol was added to 30 g (179.5 mmoL) of compound (1) (quinolinic acid) and stirred. 10 mL of concentrated sulfuric acid was added dropwise, followed by 20 mL of methyl orthoformate, which was then heated and refluxed overnight. 20 mL of methyl orthoformate was added and refluxed overnight. The mixture was cooled to 40°C, and 16 mL of bromine was added dropwise at this temperature. After one day, 8 mL of bromine was added dropwise, and the bath temperature was set to 58°C and the reaction was carried out for two days. After cooling, 300 mL of ethyl acetate and 150 mL of water were added, neutralized with sodium bicarbonate, and the organic phase was washed twice with saturated sodium bicarbonate solution after separation. The organic phase was dehydrated with anhydrous sodium sulfate, concentrated, and then crystallized with cold isopropyl alcohol. The obtained crystals were collected by filtration, washed with cold isopropyl alcohol, and dried to obtain the target product. The yield was 34.4 g and 69.9%.

[0061] Synthesis Example 1-2 Synthesis of compound (3) 10.0g of 2-ethylhexyl mercaptan (68.4mmoL) and 18.7g of compound (2) (68.2mmoL) were added to 80mL of DMF, and 14.7g of potassium carbonate was added. The system was replaced with nitrogen and the reaction was carried out at 80℃ overnight. The solvent was distilled off under reduced pressure, and then water and ethyl acetate were added for extraction. The organic phase was washed twice with dilute hydrochloric acid, then washed with water, dehydrated with anhydrous sodium sulfate, and concentrated under reduced pressure to obtain the target product. The yield was 20.0g, and the yield was 86.1%.

[0062] Synthesis Example 1-3 Synthesis of compound (4) 120mL of acetic acid and 780mg of sodium tungstate dihydrate were added to 15.5g of compound (3) (45.7mmol) and heated to 40℃. Half of 11.4mL of 30% hydrogen peroxide was added dropwise and stirred for 30 minutes. The bath temperature was set to 75℃, and the remaining hydrogen peroxide was slowly added dropwise. After the addition, the reaction was carried out at 75℃ for 2 hours and cooled to room temperature. Ethyl acetate and water were added to separate the liquid. The organic phase was washed three times with an aqueous sodium sulfite solution, then washed three times with a saturated sodium bicarbonate solution, and dehydrated with anhydrous sodium sulfate. The mixture was concentrated and the residue was purified by silica gel column chromatography to obtain the target product as a colorless oil. The yield was 14.5g and 85.4%.

[0063] Synthesis Example 1-4 Synthesis of compound (5) 100 mL of methanol was added to 6.0 g (16.2 mmol) of compound (4) and stirred at room temperature. 3.0 g of lithium hydroxide monohydrate was added to this and reacted at room temperature for 1 hour. After confirming the completion of the reaction by TLC, the mixture was acidified with concentrated hydrochloric acid and the solvent was distilled off under reduced pressure. Ethyl acetate was added to the residue and extracted, then washed three times with water. The organic phase was concentrated to obtain a colorless oily substance, which solidified when left overnight. The yield was 5.0 g and 89.9%.

[0064] Synthesis Example 1-5 Synthesis of metal complex 8 3 g of urea and 25.3 mg of ammonium molybdate hexahydrate were added to 1.0 g of compound (5), and the mixture was stirred at 160°C for 30 minutes under a nitrogen stream. 400 mg of iron(III) chloride hexahydrate and 3 g of urea were added to the reaction mixture, and the mixture was reacted at 200°C for 3 hours. After cooling to room temperature, water was added to precipitate a solid. The solid was washed with water and methanol, dried, and then purified by silica gel column chromatography. The yield was 201 mg, 21.6%.

[0065] Synthesis Example 2: Synthesis of metal complex 9 Metal complex 9 was synthesized via the following route. [ka]

[0066] Synthesis Example 2-1 Synthesis of compound (7) 100 mL of methanol was added to 10.0 g of compound (6) (4-bromophthalic anhydride), and the mixture was heated and refluxed for 1 hour. After cooling, 5.0 g of methyl orthoformate was added, and then 10 mL of acetyl chloride was slowly added dropwise. After the dropwise addition was completed, the mixture was heated and refluxed for 3 days. After concentration, ethyl acetate and water were added to separate the liquid, and the organic phase was washed with an aqueous solution of sodium hydrogen carbonate. Water was removed with anhydrous sodium sulfate, and the mixture was concentrated to obtain the target product. The yield was 10.8 g and the yield was 89.7%.

[0067] Synthesis Example 2-2 Synthesis of compound (8) 4.53g of 2-ethylhexanethiol, 8.45g of compound (7) (dimethyl 4-bromophthalate), and 6.5g of potassium carbonate were added to 60mL of N,N-dimethylformamide, and the reaction was carried out at 100°C for 24 hours under a nitrogen atmosphere. After cooling, ethyl acetate and water were added for extraction, and the mixture was washed twice with dilute hydrochloric acid and once with water, concentrated, and the residue was purified by silica gel column chromatography to obtain the target product. The yield was 5.2g and 49.6%.

[0068] Synthesis Example 2-3 Synthesis of compound (9) 30mL of acetic acid and 250mg of sodium tungstate dihydrate were added to 5.2g of compound (8) and heated to 40℃. 3.7mL of 30% hydrogen peroxide was slowly added dropwise to the mixture. After the addition, the mixture was heated to 75℃ and reacted for 2 hours, after which water and ethyl acetate were added for extraction. The organic phase was washed three times with a sodium sulfite solution and three times with an aqueous sodium hydrogen carbonate solution, concentrated, and the residue was purified by silica gel column chromatography. The yield was 4.78g, 87.2%.

[0069] Synthesis Example 2-4 Synthesis of compound (10) 40 mL of methanol and 2.2 g of lithium hydroxide monohydrate were added to 4.4 g of compound (9), and the reaction was carried out overnight. After confirming the completion of the reaction, dilute hydrochloric acid was added, the mixture was concentrated, and ethyl acetate and water were added for extraction. Upon concentration, the target product was obtained as a solid. The yield was 3.8 g and 93.3%.

[0070] Synthesis Example 2-5 Synthesis of metal complex 9 4.5 g of urea and 40 mg of ammonium molybdate tetrahydrate were added to 1.5 g of compound (10), and the mixture was heated to 165°C under a nitrogen stream. After 30 minutes, 600 mg of iron(III) chloride hexahydrate and 4.5 g of urea were added, and the reaction was carried out at 200°C for 30 minutes and at 185°C for 90 minutes. After cooling, water was added, and the precipitated solid was filtered and purified by silica gel column chromatography to obtain metal complex 9. The yield was 250 mg and 17.9%.

[0071] Synthesis Example 3 Synthesis of metal complex 24 Metal complex 24 was synthesized via the following route. [ka]

[0072] 2.8 g of compound (5) synthesized in Synthesis Example 1-4, 8.4 g of urea, and 70.8 mg of ammonium molybdate tetrahydrate were mixed and heated in an oil bath set at 165°C while stirring. After 30 minutes, 823 mg of iron(II) chloride tetrahydrate and 8.4 g of urea were added and heated in an oil bath set at 195°C for 3 hours. After cooling to 100°C, 200 mL of water was added, stirred for 1 hour, and then cooled to room temperature. The precipitated solid was filtered, washed with water, washed with methanol, and dried. The obtained crude product was purified twice by silica gel column chromatography to obtain the target product. The yield was 1.18 g and 45.3%.

[0073] Synthesis Example 4 Synthesis of metal complex 26 Metal complex 26 was synthesized via the following route. [ka]

[0074] Synthesis Example 4-1 Synthesis of compound (12) 100mL of DMF, 15.0g of 2-ethylhexyl mercaptan, and 20.0g of potassium carbonate were added to 17.3g of 4-nitrophthalonitrile (compound (11)) (100mmol), and the reaction system was replaced with nitrogen, then immersed in an oil bath set at 45°C and reacted for 24 hours with stirring. After confirming the disappearance of the raw materials by TLC, the solvent was distilled off under reduced pressure, and water and ethyl acetate were added for extraction. The organic phase was washed twice with water and then concentrated, and the residue was purified by silica gel column chromatography. The yield was 22.7g, with a yield of 83.3%.

[0075] Synthesis Example 4-2 Synthesis of compound (13) 130 mL of acetic acid and 800 mg of sodium tungstate were added to 20.0 g of compound (12) (73.4 mmoL) and stirred. The mixture was immersed in an oil bath set at 50°C, and half of 16.7 mL of 30% hydrogen peroxide was added dropwise while checking the heat generation. After reacting for 30 minutes at this temperature, the oil bath was set to 70°C, and the remaining hydrogen peroxide was slowly added dropwise. After the addition was completed, the mixture was reacted at 70°C for 2 hours, and then 300 mL of water was added dropwise. The mixture was stirred overnight under water cooling, and a solid precipitated. The solid was collected by filtration under reduced pressure, washed with water, and then dried under reduced pressure at 60°C to obtain compound (13). The yield was 19.9 g and 89.1%.

[0076] Synthesis Example 4-3 Synthesis of compound (14) 40 mL of 1-pentanol was added to 7.3 g of compound (13) and stirred. 5.5 g of 10% lithium methoxide methanol solution was added to this, and the reaction was carried out overnight at 120° C. while distilling off methanol. The solvent was distilled off under reduced pressure, and the mixture was concentrated to dryness to obtain compound (14) as a solid. This solid was used in the next reaction without purification.

[0077] Synthesis Example 4-4 Synthesis of metal complex 26 40 mL of N,N-dimethylformamide and 1.0 g of iron(II) chloride tetrahydrate were added to 5 g of the solid obtained in Synthesis Example 3-3, and the mixture was heated under reflux overnight. The mixture was allowed to cool to 80°C, and 100 mL of methanol was added and stirred for 1 hour. After cooling to room temperature, the precipitated solid was filtered, washed with methanol, and dried to obtain metal complex 26. The yield was 2.5 g.

[0078] Synthesis Example 5 Synthesis of metal complex 30 Metal complex 30 was synthesized via the following route. [ka]

[0079] 3.4 g of compound (13) synthesized in Synthesis Example 4-2 was weighed out, 25 mL of 1,2-dichlorobenzene, 740 mg of aluminum chloride, and 600 mg of ammonium chloride were added, and the mixture was immersed in an oil bath set at 205°C and reacted for 3 hours. After cooling to room temperature, water and hexane were added and stirred, and a solid precipitated. This solid was collected by filtration and washed with water and then hexane. The obtained solid was dissolved in acetone, and the insoluble matter was filtered off, and the mixture was concentrated to obtain the target product as a solid. The yield was 3.4 g and 94.9%.

[0080] <Example 1> A 50 mL stainless steel autoclave was charged with 19 mg (14 mol) of metal complex 8 and 8.4 mg (14 mol) of bis(triphenylphosphoranylidene)ammonium chloride ([PPN]Cl), and the atmosphere in the autoclave was replaced with argon. 2.0 mL (29 mmol) of propylene oxide was charged, and carbon dioxide was added until the pressure inside the autoclave reached 2.0 MPa. The autoclave was then stirred at 120°C for 1 hour to obtain a reaction mixture. After the reaction was completed, the autoclave was depressurized and the reaction mixture was diluted with methylene chloride. After adding phenanthrene as an internal standard and completely dissolving it, a small amount was withdrawn and the propylene carbonate yield and catalyst turnover frequency (the amount of propylene carbonate produced per unit time and per unit amount of metal complex, in h-1 ) was estimated.

[0081] <Example 2> The reaction was carried out in the same manner as in Example 1 except that 19 mg (14 mol) of metal complex 9 was used, and the yield of propylene carbonate and the catalyst turnover frequency were estimated.

[0082] <Example 3> The reaction was carried out in the same manner as in Example 1 except that 9.2 mg (7.0 mol) of metal complex 9, 4.1 mg (7.1 mol) of bis(triphenylphosphoranylidene)ammonium chloride ([PPN]Cl), and 1.0 mL (14 mmol) of propylene oxide were used and the reaction time was changed to 0.50 hours. The yield of propylene carbonate and the catalyst turnover frequency were estimated.

[0083] <Example 4> The reaction was carried out in the same manner as in Example 1 except that 9.2 mg (7.0 mol) of metal complex 9, 2.3 mg (7.1 mol) of tetrabutylammonium bromide (Bu4NBr), and 1.0 mL (14 mmol) of propylene oxide were used, and the yield of propylene carbonate and the catalyst turnover frequency were estimated.

[0084] <Example 5> A reaction was carried out in the same manner as in Example 1 using 9.3 mg (7.1 mol) of metal complex 9, 4.3 mg (7.5 mol) of bis(triphenylphosphoranylidene)ammonium chloride ([PPN]Cl), and 1.0 mL (14 mmol) of propylene oxide, except that the carbon dioxide pressure was 1.0 MPa, and the yield of propylene carbonate and the catalyst turnover frequency were estimated.

[0085] <Example 6> A reaction was carried out in the same manner as in Example 1 using 9.3 mg (7.1 mol) of metal complex 9, 4.1 mg (7.1 mol) of bis(triphenylphosphoranylidene)ammonium chloride ([PPN]Cl), and 1.0 mL (14 mmol) of propylene oxide, except that the carbon dioxide pressure was 5.0 MPa, and the yield of propylene carbonate and the catalyst turnover frequency were estimated.

[0086] <Example 7> The reaction was carried out in the same manner as in Example 1 using 9.3 mg (7.1 mol) of metal complex 9, 4.2 mg (7.3 mol) of bis(triphenylphosphoranylidene)ammonium chloride ([PPN]Cl), and 1.0 mL (14 mmol) of propylene oxide, except that the reaction temperature was 160° C., and the yield of propylene carbonate and the catalyst turnover frequency were estimated.

[0087] <Example 8> The reaction was carried out in the same manner as in Example 1 except that 9.2 mg (7.0 mol) of metal complex 9, 8.4 mg (15 mol) of bis(triphenylphosphoranylidene)ammonium chloride ([PPN]Cl), and 1.0 mL (14 mmol) of propylene oxide were used, and the yield of propylene carbonate and the catalyst turnover frequency were estimated.

[0088] <Example 9> The reaction was carried out in the same manner as in Example 1 except that 9.1 mg (7.1 mol) of metal complex 24, 4.1 mg (7.1 mol) of bis(triphenylphosphoranylidene)ammonium chloride ([PPN]Cl), and 1.0 mL (14 mmol) of propylene oxide were used, and the yield of propylene carbonate and the catalyst turnover frequency were estimated.

[0089] <Example 10> The reaction was carried out in the same manner as in Example 1 except that 9.0 mg (7.1 mol) of metal complex 26, 4.1 mg (7.1 mol) of bis(triphenylphosphoranylidene)ammonium chloride ([PPN]Cl), and 1.0 mL (14 mmol) of propylene oxide were used, and the yield of propylene carbonate and the catalyst turnover frequency were estimated.

[0090] <Example 11> The reaction was carried out in the same manner as in Example 1 except that 9.1 mg (7.1 mol) of metal complex 30, 4.2 mg (7.3 mol) of bis(triphenylphosphoranylidene)ammonium chloride ([PPN]Cl), and 1.0 mL (14 mmol) of propylene oxide were used, and the yield of propylene carbonate and the catalyst turnover frequency were estimated.

[0091] <Example 12> The reaction was carried out in the same manner as in Example 1, except that 8.7 mg (6.6 mol) of metal complex 9, 3.7 mg (6.4 mol) of bis(triphenylphosphoranylidene)ammonium chloride ([PPN]Cl), and 1.0 mL (13 mmol) of epichlorohydrin were used, and the yield of 4-(chloromethyl)-1,3-dioxolan-2-one and the catalyst turnover frequency were estimated.

[0092] <Example 13> The reaction was carried out in the same manner as in Example 1, except that 7.7 mg (5.9 mol) of metal complex 9, 3.6 mg (6.3 mol) of bis(triphenylphosphoranylidene)ammonium chloride ([PPN]Cl), and 1.0 mL (12 mmol) of 1,2-epoxybutane were used, and the yield of 4-ethyl-1,3-dioxolan-2-one and the catalyst turnover frequency were estimated.

[0093] <Example 14> The reaction was carried out in the same manner as in Example 1, except that 5.5 mg (4.2 mol) of metal complex 9, 2.5 mg (4.4 mol) of bis(triphenylphosphoranylidene)ammonium chloride ([PPN]Cl), and 1.0 mL (8.3 mmol) of 1,2-epoxyhexane were used, and the yield of 4-butyl-1,3-dioxolan-2-one and the catalyst turnover frequency were estimated.

[0094] <Comparative Example 1> The reaction was carried out in the same manner as in Example 1 except that 8.2 mg (14 mol) of metal complex C1 having the following structure was used, and the yield of propylene carbonate and the catalyst turnover frequency were estimated. [ka]

[0095] <Comparative Example 2> The reaction was carried out in the same manner as in Example 1 except that 9.2 mg (7.2 mol) of metal complex C2 having the following structure, 4.2 mg (7.3 mol) of bis(triphenylphosphoranylidene)ammonium chloride ([PPN]Cl), and 1.0 mL (14 mmol) of propylene oxide were used, and the yield of propylene carbonate and the catalyst turnover frequency were estimated. [ka]

[0096] <Comparative Example 3> The reaction was carried out in the same manner as in Example 1 except that 9.1 mg (7.1 mol) of metal complex C3 having the following structure, 4.1 mg (7.1 mol) of bis(triphenylphosphoranylidene)ammonium chloride ([PPN]Cl), and 1.0 mL (14 mmol) of propylene oxide were used, and the yield of propylene carbonate and the catalyst turnover frequency were estimated. [ka]

[0097] The results of Examples 1 to 14 are shown in Table 1. The results of Comparative Examples 1 to 3 are shown in Table 2. Note that R shown in Tables 1 and 2 corresponds to R in the following reaction formula. [ka]

[0098] [Table 1]

[0099] [Table 2]

[0100] From the results shown in Tables 1 and 2, it can be seen that the catalysts of Examples 1 to 14 according to the present invention have significantly higher catalyst turnover frequencies than the catalysts of Comparative Examples 1 to 3, and thus have excellent catalytic ability for the cyclic carbonate synthesis reaction. [Industrial Applicability]

[0101] The catalyst for cyclic carbonate synthesis reaction of the present invention is useful because it has high activity in the reaction of synthesizing cyclic carbonate by reacting epoxide with carbon dioxide. In addition, since it does not use rare metals, it is possible to reduce production costs and to design a production process suitable for mass production.

Claims

1. Formula (I): 【Chemistry 1】 (In the formula, M is an iron atom or an aluminum atom; E １ ~E ８ are each independently a carbon atom, an alkyl group, or a nitrogen atom, and when they are carbon atoms, each of the carbon atoms is independently bonded to a hydrogen atom, a halogen atom, or an alkyl group; R １ ~R ８ are each independently a hydrogen atom or R-SO ２ It is based on The R-SO ２ In the group, the R group is an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, an alkenyloxy group, an acyl group, or an acyloxy group, however, R １ Or R ２ At least one of the following is R-SO ２ It is based on R ３ Or R ４ At least one of the following is R-SO ２ It is based on R ５ Or R ６ At least one of the following is R-SO ２ It is based on R ７ Or R ８ At least one of the following is R-SO ２ (Based on A catalyst for a cyclic carbonate synthesis reaction comprising a metal complex of the formula (I).

2. R １ , R ３ , R ５ and R ７ is R-SO ２ group, R ２ , R ４ , R ６ and R ８ The catalyst for a cyclic carbonate synthesis reaction according to claim 1 , wherein is a hydrogen atom.

3. The R-SO ２ 2. The catalyst for cyclic carbonate synthesis reaction according to claim 1, wherein in the group, R group is an alkyl group.

4. 4. The catalyst for a cyclic carbonate synthesis reaction according to claim 3, wherein the alkyl group is a branched alkyl group having 3 to 12 carbon atoms.

5. The catalyst for a cyclic carbonate synthesis reaction according to claim 4, wherein the alkyl group is 2-ethylhexyl.

6. 2. The catalyst for a cyclic carbonate synthesis reaction according to claim 1, wherein M is an iron atom.

7. E １ ~E ８ The catalyst for a cyclic carbonate synthesis reaction according to claim 1 , wherein is a carbon atom to which a hydrogen atom is bonded.

8. The metal complex has the following formula: 【Chemistry 2】 【Chemistry 3】 【Chemistry 4】 【Chemistry 5】 【Chemistry 6】 【Chemistry 7】 【Chemistry 8】 【Chemistry 9】 【Chemistry 10】 【Chemistry 11】 【Chemistry 12】 The catalyst for cyclic carbonate synthesis reaction according to claim 1, wherein the catalyst is represented by the formula:

9. A method for producing a cyclic carbonate, comprising using a metal complex of formula (I) as a catalyst in a reaction between an epoxide and carbon dioxide to synthesize the cyclic carbonate. 【Chemistry 13】 (In the formula, M is an iron atom or an aluminum atom; E １ ~E ８ are each independently a carbon atom or a nitrogen atom, and if a carbon atom, each of the carbon atoms is independently bonded to a hydrogen atom, a halogen atom, or an alkyl group; R １ ~R ８ each independently represents a hydrogen atom, an alkyl group, or R-SO ２ It is based on the R group is an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, an alkenyloxy group, an acyl group, or an acyloxy group; however, R １ Or R ２ At least one of the following is R-SO ２ It is based on R ３ Or R ４ At least one of the following is R-SO ２ It is based on R ５ Or R ６ At least one of the following is R-SO ２ It is based on R ７ Or R ８ At least one of the following is R-SO ２ (Based on

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