JP2007254309A - New carbonic ester - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new carbonic ester advantageous as an industrial carbonyl source. <P>SOLUTION: The new carbonic ester is represented by formula(1). A method for producing an aromatic carbonic ester is also provided, comprising conducting a transesterification between the above carbonic ester and the corresponding aromatic hydroxy compound. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to a novel carbonic acid ester compound, and more particularly, to a carbonic acid ester compound used as a carbonyl source, and particularly useful as an intermediate in a transesterification polycarbonate production process.
Carbonate esters are used as additives such as gasoline additives to improve octane number and diesel fuel additives to reduce particles in exhaust gas, as well as organic compounds such as battery electrolytes, polycarbonate, urethane, pharmaceuticals and agricultural chemicals. This compound is useful as an alkylating agent, a carbonylating agent, a solvent, and the like when synthesizing.

  Conventionally, when carbonate ester is used as a carbonate source, dimethyl carbonate is often used. For example, when dimethyl carbonate is used as a raw material for polycarbonate, a method of simply transesterifying with an aromatic hydroxy compound to obtain arylmethyl carbonate or diaryl carbonate is employed. For example, the following formulas (2) to (4) It is produced by transesterification reaction.

  That is, as shown in the following formula (2), transesterification with phenol gives methylphenyl carbonate, then diphenyl carbonate is obtained using a disproportionation reaction according to the following formula (3), and further according to the following formula (4). A method of transesterifying with bisphenol A to obtain a polycarbonate is widely known.

  When producing methyl carbonate, diphenyl carbonate, and polycarbonate by the above reaction, the above reaction formulas (2) to (4) are all equilibrium reactions, and the equilibrium of reaction formula (2) is particularly biased toward the raw material side. In general, in order to shift the equilibrium to the product side, it is effective to extract one or both of the products out of the system. However, when dimethyl carbonate is used, it is difficult to remove only the product by reactive distillation because methanol as a product is known to have an azeotropic composition with dimethyl carbonate as a raw material. Many efforts have been made to avoid this azeotropy (for example, Patent Document 1). However, the fundamental problem of poor reaction efficiency due to extraction of the starting dialkyl carbonate during the reaction has not been solved. Therefore, a large energy consumption method is employed in which a large amount of dimethyl carbonate is used with respect to phenol as one raw material and is extracted out of the system together with methanol as a product. Furthermore, the process of extracting methanol from the azeotropic mixture of dimethyl carbonate and methanol to concentrate dimethyl carbonate is technically difficult and consumes a lot of energy. From the above, there is a problem that the equilibrium of the reaction for obtaining an alkylaryl carbonate such as methylphenyl carbonate, which is a raw material for diaryl carbonate, is biased to the production system by a simple method.

Methods using phosgene and carbon monoxide as carbonyl sources for alkylaryl carbonates and diaryl carbonates are also known, but these methods are highly toxic to phosgene and carbon monoxide, and facilities for ensuring safety for safe production However, there is a problem that a large investment is required.
As described above, in the prior art relating to the production of diaryl carbonate, the equilibrium is remarkably biased to the original system, or there is azeotropy between the raw material and the product, and the equilibrium is not shifted by a simple method. There were issues such as. Some of the above problems are the same when dimethyl carbonate is used as the battery electrolyte raw material intermediate. Due to the azeotrope of dimethyl carbonate and methanol, there is a problem that the equilibrium cannot be easily deviated even when transesterification with other alcohols to obtain a carbonate ester having a different structure.
On the other hand, there is a carbonate ester developed by the present inventors in order to solve the above-described problems (Patent Document 2). The present invention has been completed by further advancing the invention.
JP 7-330687 A JP 2005-015431 A

  An object of the present invention is to provide a novel carbonate ester that is a raw material that is easy to handle and highly reactive as a raw material for efficiently producing an aromatic carbonate, and an aromatic using the carbonate ester It is providing the manufacturing method of carbonate ester.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have solved the problem that the raw material and the product are azeotropic and cannot easily shift the equilibrium, and further improve the reactivity. Completed the invention.
When the carbonate ester of the present invention was used in place of dimethyl carbonate in the reaction formula (2), it was surprisingly found that the reaction rate was also improved, and the present invention was completed.
That is, the present invention is as follows.
[1] Carbonate represented by the following formula (1).

[2] A method for producing an aromatic carbonate, comprising transesterifying the carbonate ester according to the above [1] with an aromatic hydroxy compound.

  The present invention provides a novel carbonate ester that is a raw material that is easy to handle and highly reactive as a raw material for efficiently producing an aromatic carbonate, and an aromatic carbonate using the carbonate The production method can be provided and the use of a novel carbonate ester improves the productivity and is very useful in the industry.

Hereinafter, the present invention will be described in detail.
The carbonate ester of the present invention is a carbonate ester represented by the following formula (1).

  As the method for producing a carbonate ester of the present invention, a known carbonate ester production method is preferably used. For example, a method obtained from phosgene and alcohol, an oxidative carbonylation method using carbon monoxide, a method obtained from carbon dioxide and alcohol, and the like can be used. When the carbonate ester of the present invention is used as a reaction raw material, it may be very high purity, may contain other impurities, may be a mixture with other carbonate ester, and may be an electrolyte. In the case of using as, the composition which added the required component may be sufficient. However, when manufacturing diphenyl carbonate, it is preferable not to contain a nitrogen-containing compound as much as possible. Nitrogen-containing compounds are undesirable components because they easily react with carbonates and cause the formation of impurities and by-products. There are stoichiometric carbon atoms and hydrogen atoms at unnamed bending points and line ends in each of formulas (1) to (4).

  As a preferred method for producing the carbonate ester of the present invention, carbon dioxide and 4-methyl-2-pentanol are used as raw materials. As such a production method, a method invented by the present inventors (for example, PCT / JP02 / 13809) can be preferably used. Dibutyltin oxide and 4-methyl-2-pentanol are reacted and water is removed by distillation to obtain a tin alkoxide. The obtained tin alkoxide is reacted with carbon dioxide to produce bis (4- Methyl-2-pentyl) can be obtained. By this method, bis (4-methyl-2-pentyl) carbonate containing no urea or the like that generates the above-mentioned undesirable by-products can be obtained. Since (1) has two asymmetric carbons, there are optical isomers and diastereomers, but they may be used alone or as a mixture of these isomers.

If the carbonate ester of the present invention is used, the problem of dimethyl carbonate that has been widely used can be solved. That is, dimethyl carbonate has an azeotrope of dimethyl carbonate and methanol, making it difficult to shift the equilibrium reaction. By reacting the carbonate ester of the present invention with an aromatic hydroxy compound, (4-methyl-2-pentyl) aryl carbonate and diaryl carbonate can be obtained.
The aromatic hydroxy compound used in the present invention is not particularly limited.
The aromatic hydroxy compound used in the present invention is represented by the following general formula (5), and any compound can be used as long as the hydroxyl group is directly bonded to the aromatic group. May be.
ArOH (5)
(In the formula, Ar represents an aromatic group having 5 to 30 carbon atoms.)

Examples of such aromatic hydroxy compounds having Ar include phenol, cresol (each isomer), xylenol (each isomer), trimethylphenol (each isomer), tetramethylphenol (each isomer), and ethylphenol. (Each isomer), propylphenol (each isomer), butylphenol (each isomer), diethylphenol (each isomer), methylethylphenol (each isomer), methylpropylphenol (each isomer), dipropylphenol (Each isomer), methylbutylphenol (each isomer), pentylphenol (each isomer), hexylphenol (each isomer), various alkylphenols such as cyclohexylphenol (each isomer); methoxyphenol (each isomer) , Various aldehydes such as ethoxyphenol (each isomer) Alkoxy phenols and the like. Preferable examples include phenol and cresol (each isomer), and industrially most useful diphenyl carbonate is obtained.
The method for producing an aromatic carbonate from the carbonate ester of the present invention is an equilibrium reaction mainly based on transesterification of a carbonate ester and an aromatic hydroxy compound. It is preferable to carry out the reaction while extracting the alcohol produced by elimination, and in this case, it is preferable that the aromatic hydroxy compound to be used has a boiling point higher than that of the alkyl alcohol constituting the carbonate ester.

The alkyl alcohol constituting the carbonic acid ester of the present invention is 4-methyl-2-pentanol, which is advantageous because it has a lower boiling point than phenol, which is an aromatic hydroxy compound having the lowest boiling point. Surprisingly, it was found that the reaction rate was remarkably improved by using the carbonate ester of the present invention, and the present invention was completed.
When performing the above-described reaction, a catalyst may be added.
As described above, the reaction is mainly a transesterification reaction, and by transesterification, alkylaryl carbonate and some diaryl carbonate are obtained from dialkyl carbonate, but in addition to the fact that the equilibrium is biased toward the original system, the reaction rate is slow. Therefore, when producing aromatic carbonates by this method, several proposals have been made to improve them, and known methods can be preferably used in the present invention.

A number of metal-containing catalysts are known for proposals relating to catalysts for increasing the reaction rate. Known transesterification catalysts can also be used in the present invention.
Compounds that produce Lewis acids or Lewis acids, such as transition metal halides, as catalysts in methods for producing alkylaryl carbonates and / or mixtures containing alkylaryl carbonates and diaryl carbonates by reacting dialkyl carbonates with aromatic hydroxy compounds [Japanese Patent Laid-Open Nos. 51-105032, 56-123948, 56-123949 (West German Patent Publication 2528412, British Patent 1499530, US Pat. No. 4,182,726) Description)], tin compounds such as organotin alkoxides and organotin oxides [Japanese Patent Laid-Open No. 54-48733 (West German Patent Publication No. 2736062), Japanese Patent Laid-Open No. 54-63023, Japanese Patent Laid-Open No. 60-169444] Gazette (U.S. Pat. No. 4,554,110), JP No. 60-169445 (U.S. Pat. No. 4,552,704), Japanese Patent Laid-Open No. 62-277345, Japanese Patent Laid-Open No. 1-265063, alkali metal or alkaline earth metal salts and alkoxides -176932), lead compounds (JP-A 57-176932), metal complexes of copper, iron, zirconium, etc. (JP-A 57-183745), titanates [JP-A 58-185536 (U.S. Pat. No. 4,410,464)], a mixture of Lewis acid and protonic acid [Japanese Patent Laid-Open No. 60-173016 (U.S. Pat. No. 4,609,501)], Sc, Mo, Mn, Bi And compounds such as Te (Japanese Patent Laid-Open No. 1-265064), ferric acetate (Japanese Patent Laid-Open No. 61-172852), and the like have been proposed.

Aromatic carbonates can be produced only by transesterification, but they can also be produced by disproportionation of alkylaryl carbonates produced by transesterification. The disproportionation reaction here is a reaction for producing dialkyl carbonate and aromatic carbonate from two molecules of alkylaryl carbonate.
There also occurs a reaction in which the alkylaryl carbonate further reacts with an aromatic hydroxy compound to become an aromatic carbonate. Both reactions are equilibrium reactions. Therefore, a catalyst for catalyzing the disproportionation reaction may be present together with the above-described transesterification catalyst. Many examples of such catalysts have also been proposed.

  Examples of such catalysts include Lewis acids and transition metal compounds capable of generating Lewis acids [Japanese Patent Laid-Open No. 51-75044 (West German Patent Publication No. 2552907, US Pat. No. 4,045,464)], polymeric properties A tin compound (Japanese Patent Laid-Open No. 60-169444 (US Pat. No. 4,554,110)), a general formula R—X (═O) OH (where X is selected from Sn and Ti, and R is a monovalent hydrocarbon) Selected from the group), [JP-A-60-169445 (US Pat. No. 4,552,704)], a mixture of Lewis acid and protonic acid [JP-A-60-173016 ( U.S. Pat. No. 4,609,501)), lead catalyst (Japanese Patent Laid-Open No. 1-93560), titanium and zirconium compounds (Japanese Patent Laid-Open No. 1-265062), tinization Things (JP-A-1-265063), Sc, Mo, Mn, Bi, compounds such as Te (JP-A-1-265064) have been proposed.

  The reaction for obtaining (4-methyl-2-pentyl) aryl carbonate or diaryl carbonate from the carbonate ester of the present invention and the aromatic hydroxy compound is shifted to the production system side as much as possible by devising the reaction system, and the aromatic carbonate There are also attempts to improve the yield of esters. For example, there is also known a method of distilling off alcohols by-produced from the reaction from the reaction mixture using an apparatus provided with a distillation column at the top of the reactor [Japanese Patent Laid-Open No. 56-123948 (US Pat. No. 4182726), JP-A 56-25138, JP-A 60-169444 (US Pat. No. 4,554,110), JP-A 60-169445. (U.S. Pat. No. 4,552,704), JP-A-60-173016 (U.S. Pat. No. 4,609,501), JP-A-61-272852, Examples of -291545 and Examples of JP-A-62-277345].

A dialkyl carbonate and an aromatic hydroxy compound are continuously supplied to a multistage distillation column, reacted continuously in the column, and low-boiling components including by-produced alcohol are continuously extracted by distillation, and the produced alkyl carbonate A method for extracting an aryl-containing component from the lower part of the column (Japanese Patent Laid-Open No. 3-291257) and a dialkyl carbonate produced as a by-product by continuously supplying alkylaryl carbonate to a multistage distillation column and continuously reacting in the column Proposals such as a method of continuously extracting a low-boiling component containing NO by distillation and extracting a component containing the produced aromatic carbonate from the lower part of the column (JP-A-4-9358) can be preferably used.
These methods are methods for efficiently and continuously producing aromatic carbonates. As a similar continuous production method, a method of catalytic transesterification in a column type reactor (Japanese Patent Laid-Open No. 6-41022). Gazette, JP-A-6-157424, JP-A-6-184058), a method of connecting a plurality of reaction vessels in series (JP-A-6-234707, JP-A-6-263694), bubble column reaction A method using a reactor (Japanese Patent Laid-Open No. 6-298700), a method using a vertically long reaction tank (Japanese Patent Laid-Open No. 6-345697), and the like have been proposed. In the case of producing aromatic carbonates industrially by these methods, a method of stably operating for a long period of time has also been proposed.

  In JP-A-6-157410, when an aromatic carbonate is produced from a dialkyl carbonate and an aromatic hydroxy compound, it is connected to the reactor so that the concentration of the aliphatic alcohol in the reactor is 2% by weight or less. Discloses a method for extracting aliphatic alcohol from a distillation column and describes that stable continuous operation can be performed. This publication is for preventing the problem of catalyst precipitation in the distillation column. In Japanese Patent Application Laid-Open No. 9-11049, an aromatic polyvalent hydroxy compound and / or its residue is kept at a weight ratio of 2 or less with respect to the metal component of the catalyst in the liquid containing the catalyst in the system. A method is disclosed that prevents the precipitation of slag and enables stable operation for a long period of time.

It is also known that high boiling substances are by-produced in the production of aromatic carbonates. For example, in Japanese Patent Application Laid-Open No. Sho 61-172852, when diphenyl carbonate is produced by transesterifying dimethyl carbonate with phenol, an impurity having a boiling point similar to that of diphenyl carbonate is by-produced, and this impurity is mixed into diphenyl carbonate. By doing so, it is described that the final object, for example, polycarbonate, is colored.
Although not specifically described in the publication, aryloxycarbonyl- (hydroxy) -arene, which is an isomer by fleece transition of the aromatic carbonate, is cited as an impurity having a boiling point similar to that of the aromatic carbonate. It is done. For example, when the aromatic carbonate is diphenyl carbonate, phenyl salicylate is exemplified as a compound corresponding to aryloxycarbonyl- (hydroxy) -arene. Phenyl salicylate is a high-boiling substance whose boiling point is 4-5 ° C. higher than that of diphenyl carbonate. When the reaction is carried out for a long time, the high-boiling substance gradually accumulates in the system, so that the high-boiling substance mixed in the aromatic carbonate, which is a product, increases and the product purity is lowered. Further, since the boiling point of the reaction solution increases as the high-boiling substance increases, there is a problem that the by-product of the high-boiling substance is further accelerated. For example, a method such as JP-A-11-92429 Therefore, an aromatic carbonate having high purity can be stably produced without requiring a large amount of the catalyst.

The carbonate transesterification catalyst used in the present invention is a transesterification catalyst that promotes the reaction of the reaction formula (2), and is selected from, for example, the following compounds.
<Lead compounds> Lead oxides such as PbO, PbO ₂ and Pb ₃ O ₄ ; Lead sulfides such as PbS and Pb ₂ S; Lead hydroxides such as Pb (OH) ₂ and Pb ₂ O ₂ (OH) ₂ Ninamates such as Na ₂ PbO ₂ , K ₂ PbO ₂ , NaHPbO ₂ , KHPbO ₂ ; Na ₂ PbO ₃ , Na ₂ H ₂ PbO ₄ , K ₂ PbO ₃ , K ₂ [Pb (OH) ₆ ], _{K 4 PbO 4, Ca 2 PbO} 4, lead-acid salts such as _{CaPbO 3; PbCO 3, 2PbCO 3} · Pb (OH) carbonates ₂ such as lead and its basic _{salts; Pb (OCOCH 3) 2,} Pb ( Lead salts of organic acids such as OCOCH ₃ ) ₄ , Pb (OCOCH ₃ ) ₂ .PbO.3H ₂ O and carbonates and basic salts thereof; Bu ₄ Pb, Ph ₄ Pb, Bu ₃ PbCl, Ph ₃ PbBr, Ph ₃ b (or _{Ph 6 Pb 2), Bu 3} PbOH, Ph 3 organic lead compounds such as PbO (Bu is a butyl group, Ph represents a phenyl _{group.); Pb (OCH 3)} 2, (CH 3 O) Pb (OPh), Pb (OPh) _{2 and} other alkoxyleads, aryloxyleads; Pb-Na, Pb-Ca, Pb-Ba, Pb-Sn, Pb-Sb and other lead alloys; Lead minerals such as ores, and hydrates of these lead compounds;

<Compound of copper group _{metals> CuCl, CuCl 2, CuBr,} CuBr 2, CuI, CuI 2, Cu (OAc) 2, Cu (acac) 2, olefin _{copper, Bu2Cu, (CH 3 O)} 2 Cu, AgNO 3 , AgBr, silver picrate, AgC ₆ H ₆ ClO ₄ , Ag (Burvalene) ₃ NO ₃ , [AuC≡C—C (CH ₃ ) ₃ ] n, copper such as [Cu (C ₇ H ₈ ) Cl] 4 Group metal salts and complexes (acac represents an acetylacetone chelate ligand);
<Alkali metal complexes> Alkali metal complexes such as Li (acac) and LiN (C ₄ H ₉ ) ₂ ;
<Zinc Complex> Zinc complex such as Zn (acac) ₂ ;
<Cadmium Complex> Cd complex such as Cd (acac) ₂ ;
<Compound of iron group metal> Fe (C ₁₀ H ₈ ) (CO) ₅ , Fe (CO) ₅ , Fe (C ₄ H ₆ ) (CO) ₃ , Co (mesitylene) ₂ (PEt2Ph) ₂ , CoC ₅ F A complex of an iron group metal such as ₅ (CO) ₇ , Ni-π-C ₅ H ₅ NO, ferrocene;

<Zirconium complex> Zirconium complex such as Zr (acac) ₄ and zirconocene;
<Lewis Acid Compounds> AlX ₃ , TiX ₃ , TiX ₄ , VOX ₃ , VX ₅ , ZnX ₂ , FeX ₃ , SnX ₄ (where X is a halogen, an acetoxy group, an alkoxy group, or an aryloxy group). Lewis acids and transition metal compounds that generate Lewis acids;
<Organotin _{compounds> (CH 3) 3 SnOCOCH 3} , (C 2 H 5) 3 SnOCOC 6 H 5, Bu 3 SnOCOCH 3, Ph 3 SnOCOCH 3, Bu 2 Sn (OCOCH 3) 2, Bu 2 Sn (OCOC 11 H ₂₃ ) ₂ , Ph ₃ SnOCH ₃ , (C ₂ H ₅ ) ₃ SnOPh, Bu ₂ Sn (OCH ₃ ) ₂ , Bu ₂ Sn (OC ₂ H ₅ ) ₂ , Bu ₂ Sn (OPh) ₂ , Ph ₂ Sn (OCH) ₃ ) ₂ , organotin compounds such as (C ₂ H ₅ ) ₃ SnOH, Ph ₃ SnOH, Bu ₂ SnO, (C ₈ H ₁₇ ) ₂ SnO, Bu ₂ SnCl ₂ , BuSnO (OH);

Of course, even if these catalyst components are reacted with organic compounds present in the reaction system, such as alcohols, aromatic hydroxy compounds, alkyl aryl carbonates, aromatic carbonates, dialkyl carbonates, etc. It may be good or may be heat-treated with raw materials or products prior to the reaction. These transesterification catalysts are preferably those having high solubility in the reaction solution under the reaction conditions. Preferred transesterification catalysts include PbO, Pb (OH) ₂ , Pb (OPh) ₂ ; TiCl ₄ , Ti (OPh) ₄ ; SnCl ₄ , Sn (OPh) ₄ , Bu ₂ SnO, Bu ₂ Sn (OPh) ₂ ; FeCl ₃ , Fe (OH) ₃ , Fe (OPh) _3, etc., or those obtained by treating them with phenol or a reaction solution or the like.

  The reaction for obtaining an aromatic carbonate from the carbonate of the present invention is a process for obtaining an aromatic carbonate by transesterification of bis (4-methyl-2-pentyl) carbonate and an aromatic hydroxy compound as described above. In order to proceed with this equilibrium reaction advantageously, a method of proceeding the reaction while extracting alcohol is an advantageous method. Since the disproportionation reaction is also subject to equilibrium restrictions, bis (4-methyl-2-pentyl) carbonate and aromatics produced by the disproportionation reaction will increase if more diaryl carbonates are obtained from aromatic carbonates. A method in which one of the carbonates is reacted while being extracted out of the system is advantageous, and it is preferable to carry out the reaction while extracting bis (4-methyl-2-pentyl) carbonate out of the system.

In the production of the aromatic carbonate, the catalyst for catalyzing the disproportionation reaction may be added together with the carbonate transesterification reaction catalyst.
Examples of such catalysts include Lewis acids and transition metal compounds capable of generating Lewis acids [Japanese Patent Laid-Open No. 51-75044 (West German Patent Publication No. 2552907, US Pat. No. 4,045,464)], polymeric properties A tin compound (Japanese Patent Laid-Open No. 60-169444 (US Pat. No. 4,554,110)), a general formula R—X (═O) OH (where X is selected from Sn and Ti, and R is a monovalent hydrocarbon) Selected from the group), [JP-A-60-169445 (US Pat. No. 4,552,704)], a mixture of Lewis acid and protonic acid [JP-A-60-173016 ( U.S. Pat. No. 4,609,501)), lead catalyst (Japanese Patent Laid-Open No. 1-93560), titanium and zirconium compounds (Japanese Patent Laid-Open No. 1-265062), tinization Things (JP-A-1-265063), Sc, Mo, Mn, Bi, compounds such as Te (JP-A-1-265064) have been proposed.

The disproportionation reaction catalyst used in the present invention is a disproportionation reaction catalyst that promotes the reaction of the reaction formula (3), and the same catalyst as the carbonate transesterification reaction catalyst can be used.
For example, it is selected from the following compounds.
<Lead compounds> Lead oxides such as PbO, PbO ₂ and Pb ₃ O ₄ ; Lead sulfides such as PbS and Pb ₂ S; Lead hydroxides such as Pb (OH) ₂ and Pb ₂ O ₂ (OH) ₂ Ninamates such as Na ₂ PbO ₂ , K ₂ PbO ₂ , NaHPbO ₂ , KHPbO ₂ ; Na ₂ PbO ₃ , Na ₂ H ₂ PbO ₄ , K ₂ PbO ₃ , K ₂ [Pb (OH) ₆ ], _{K 4 PbO 4, Ca 2 PbO} 4, lead-acid salts such as _{CaPbO 3; PbCO 3, 2PbCO 3} · Pb (OH) carbonates ₂ such as lead and its basic _{salts; Pb (OCOCH 3) 2,} Pb ( Lead salts of organic acids such as OCOCH ₃ ) ₄ , Pb (OCOCH ₃ ) ₂ .PbO.3H ₂ O and carbonates and basic salts thereof; Bu ₄ Pb, Ph ₄ Pb, Bu ₃ PbCl, Ph ₃ PbBr, Ph ₃ P organic lead compounds such as b (or Ph ₆ Pb ₂ ), Bu ₃ PbOH, Ph ₃ PbO (Bu represents a butyl group, Ph represents a phenyl group); Pb (OCH ₃ ) ₂ , (CH ₃ O) Pb (OPh), Pb (OPh) _{2 and} other alkoxyleads, aryloxyleads; Pb-Na, Pb-Ca, Pb-Ba, Pb-Sn, Pb-Sb and other lead alloys; Lead minerals such as ores, and hydrates of these lead compounds;

<Compound of copper group _{metals> CuCl, CuCl 2, CuBr,} CuBr 2, CuI, CuI 2, Cu (OAc) 2, Cu (acac) 2, olefin _{copper, Bu 2 Cu, (CH 3} O) 2 Cu, AgNO ₃ , AgBr, silver picrate, AgC ₆ H ₆ ClO ₄ , Ag (Bulvalene) ₃ NO ₃ , [AuC≡C—C (CH ₃ ) ₃ ] n, [Cu (C ₇ H ₈ ) Cl] 4, etc. And copper group metal salts and complexes (acac represents an acetylacetone chelate ligand);
<Alkali metal complexes> Alkali metal complexes such as Li (acac) and LiN (C ₄ H ₉ ) 2;
<Zinc complex> Zinc complex such as Zn (acac) 2;
<Cadmium Complex> Cadmium Complexes such as Cd (acac) 2;
<Compound of iron group metal> Fe (C ₁₀ H ₈ ) (CO) ₅ , Fe (CO) ₅ , Fe (C ₄ H ₆ ) (CO) ₃ , Co (mesitylene) ₂ (PEt ₂ Ph) ₂ , CoC Complexes of iron group metals such as ₅ F ₅ (CO) ₇ , Ni-π-C ₅ H ₅ NO, ferrocene;

<Zirconium Complex> Zirconium complexes such as Zr (acac) ₄ and zirconocene;
<Lewis Acid Compounds> AlX ₃ , TiX ₃ , TiX ₄ , VOX ₃ , VX ₅ , ZnX ₂ , FeX ₃ , SnX ₄ (where X is a halogen, an acetoxy group, an alkoxy group, or an aryloxy group). Lewis acids and transition metal compounds that generate Lewis acids;
<Organotin _{compounds> (CH 3) 3 SnOCOCH 3} , (C 2 H 5) 3 SnOCOC 6 H 5, Bu 3 SnOCOCH 3, Ph 3 SnOCOCH 3, Bu 2 Sn (OCOCH 3) 2, Bu 2 Sn (OCOC 11 _{H 23) 2, Ph 3 SnOCH} 3, (C 2 H 5) 3 SnOPh, Bu 2 Sn (OCH 3) 2, Bu 2 Sn (OC 2 H 5) 2, Bu 2 Sn (OPh) 2, Ph 2 Sn Organotin compounds such as (OCH ₃ ) ₂ , (C ₂ H ₅ ) ₃ SnOH, Ph ₃ SnOH, Bu ₂ SnO, (C ₈ H ₁₇ ) ₂ SnO, Bu ₂ SnCl ₂ , BuSnO (OH);

Of course, even if these catalyst components are reacted with organic compounds present in the reaction system, such as alcohols, aromatic hydroxy compounds, alkyl aryl carbonates, aromatic carbonates, dialkyl carbonates, etc. It may be good or may be heat-treated with raw materials or products prior to the reaction. These disproportionation reaction catalysts are preferably those having high solubility in the reaction solution under the reaction conditions. Preferred disproportionation reaction catalysts include PbO, Pb (OH) ₂ , Pb (OPh) ₂ ; TiCl ₄ , Ti (OPh) ₄ ; SnCl ₄ , Sn (OPh) ₄ , Bu ₂ SnO, Bu ₂ Sn (OPh ) ₂ ; FeCl ₃ , Fe (OH) ₃ , Fe (OPh) ₃ , or the like, or those treated with phenol or a reaction solution, or the like.

  The amount of the aromatic hydroxy compound used when producing an aromatic carbonate such as (4-methyl-2-pentyl) aryl carbonate or diaryl carbonate from the carbonate ester of the present invention and the aromatic hydroxy compound is determined by the amount of carbonic acid used. It can be used in a range of 0.1 to 10,000 times in terms of molar ratio with respect to the amount of bis (4-methyl-2-pentyl). Since the reaction is mainly an equilibrium reaction, it is advantageous that the amount of the aromatic hydroxy compound is large. However, if the amount used is increased, the reactor becomes large, and a large distillation column or the like is used for the subsequent separation of the product. Therefore, the range of 1 to 1000 times that of bis (4-methyl-2-pentyl) carbonate, which is the carbonate of the present invention, is preferable.

The compound supplied to the reaction is mainly bis (4-methyl-2-pentyl) carbonate, an aromatic hydroxy compound, and if necessary, a catalyst, even if impurities that do not adversely affect the reaction are mixed. It doesn't matter.
The amount of catalyst in the case of using the catalyst in the present invention depends on the type of catalyst used, the type of reactor, and the type and amount ratio of aromatic hydroxy compound, reaction temperature, reaction pressure and other reaction conditions. Although it is different, it is usually used at 0.0001 to 50% by weight, expressed as a ratio to the total weight of bis (4-methyl-2-pentyl) carbonate and aromatic hydroxy compound as feed materials. Moreover, when using a solid catalyst, the catalyst amount of 0.01-75 volume% is preferably used with respect to the empty space of a reactor.

These feed materials may contain products such as alcohol, (4-methyl-2-pentyl) aryl carbonate, and diaryl carbonate. However, since this reaction is a reversible reaction, these products are produced. Among the products, when the concentration is too high, the reaction rate of the raw material is lowered, which may not be preferable.
The amount ratio of the dialkyl carbonate to be supplied and the aromatic hydroxy compound may vary depending on the type and amount of the catalyst and the reaction conditions, but the aromatic hydroxy compound is usually in a molar ratio with respect to the dialkyl carbonate in the feedstock. It is preferable to supply in the range of 0.01 to 1000 times.

The reaction time of the reaction varies depending on the reaction conditions, the type of reactor and the internal structure, but is usually 0.001 to 50 hours, preferably 0.01 to 10 hours, more preferably 0.05 to 5 hours. . The reaction temperature is the temperature in the reactor and varies depending on the types of dialkyl carbonate and aromatic hydroxy compound used as raw material compounds, but is usually 50 to 350 ° C., preferably 100 to 280 ° C. The reaction pressure varies depending on the type of raw material compound used, the reaction temperature, and the like, but may be any of reduced pressure, normal pressure, and increased pressure, and is usually performed in the range of 10 Pa to 20 MPa.
In the present invention, it is not always necessary to use a solvent, but for the purpose of facilitating the reaction operation, a suitable inert solvent such as ethers, aliphatic hydrocarbons, aromatic hydrocarbons, halogen modification, etc. Aliphatic hydrocarbons, halogen aromatic hydrocarbons and the like can be used as the reaction solvent. In addition, an inert gas such as nitrogen, helium, or argon may be present in the reaction system as a substance inert to the reaction, or a continuous multistage distillation column may be used for the purpose of accelerating the distillation of the low-boiling by-product. From the lower part, the above inert gas or a low-melting-point organic compound inert to the reaction may be introduced in the form of a gas.

  After completion of the reaction, the catalyst, bis (4-methyl-2-pentyl) carbonate, aromatic carbonate, aromatic hydroxy compound and alcohol are separated by a known method to obtain an aromatic carbonate. There is no restriction | limiting in particular in the form of the reactor used by the said reaction, Well-known various methods, such as a stirring tank system, a multistage stirring tank system, a system using a multistage distillation column, and a system combining these, are used. These reactors can be used either batchwise or continuously. In terms of efficiently shifting the equilibrium to the production system side, a method using a multistage distillation column is preferred, and a continuous method using a multistage distillation column is particularly preferred. The multi-stage distillation column is a distillation column having a multi-stage of two or more theoretical distillation stages, and any column can be used as long as continuous distillation is possible.

  Examples of such a multistage distillation column include a plate column type using a tray such as a foam tray, a perforated plate tray, a valve tray, a counterflow tray, etc., a Raschig ring, a lessing ring, a pole ring, a Berle saddle, an interlock. Any of those usually used as a multi-stage distillation column, such as a packed column type packed with various packings such as saddle, Dixon packing, McMahon packing, helipak, sulzer packing, and melapack, can be used. Furthermore, a shelf-packed mixed tower type having both a shelf portion and a portion filled with a packing is also preferably used. When a continuous process is carried out using a multistage distillation column, the starting material and the reactant are continuously fed into the continuous multistage distillation column, and the liquid phase or gas-liquid is present in the presence of the metal-containing catalyst in the distillation column. At the same time, a transesterification or disproportionation reaction between the two substances is performed in the phase, and at the same time, the produced high-boiling point reaction mixture containing the aromatic carbonate or aromatic carbonate mixture is extracted from the lower part of the distillation column in a liquid state, Aromatic carbonates are produced by continuously extracting the low-boiling reaction mixture containing the by-product produced from the upper part of the distillation column by distillation.

EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples.
<Analysis method>
1) NMR analysis method apparatus: JNM-A400FTNMR system manufactured by JEOL Ltd. (1) ¹ H, ¹³ C-NMR analysis Sample solution was weighed in the range of 0.1 to 0.5 g, About 0.9 g of chloroform is added to prepare an NMR analysis sample solution.

2) Carbon chromatographic gas chromatographic analysis apparatus: GC-2010 system manufactured by Shimadzu Corporation (1) Preparation of analysis sample solution About 0.20 g of the reaction solution was weighed and dehydrated dimethylformamide or acetonitrile was about 2. Add 5 ml.
Furthermore, about 0.06 g of diphenyl ether is added as an internal standard to obtain a gas chromatography analysis sample solution.
(2) Gas chromatography analysis condition column: DB-1 (J & W Scientific)
Liquid phase: 100% dimethylpolysiloxane Length: 30m
Inner diameter: 0.25mm
Film thickness: 1μm
Column temperature: 50 ° C. (temperature rising at 10 ° C./min) 300 ° C.
Injection temperature: 300 ° C
Detector temperature: 300 ° C
Detection method: FID
(3) Quantitative analysis method Quantitative analysis of an analysis sample solution is performed based on a calibration curve prepared by analyzing a standard sample of each standard substance.

2) Carbon dioxide gas mass spectrometer: Agilent Technologies GC6890A, 5973N Mass
Selective Detector
(1) Preparation of analysis sample solution About 0.02 g of the reaction solution is weighed, and about 2.5 ml of dehydrated dimethylformamide or acetonitrile is added to obtain a gas mass spectrometry sample solution.
(2) Gas mass spectrometry condition column: DB-5 (J & W Scientific)
Liquid phase: 95% methylpolysiloxane, 5% phenylmethylpolysiloxane Length: 30m
Inner diameter: 0.25mm
Film thickness: 0.25 μm
Column temperature: After 5 minutes at 50 ° C., the temperature was raised to 200 ° C. at 10 ° C./minute, and after 5 minutes, the temperature was further raised to 300 ° C.
Injection temperature: 300 ° C
Detector temperature: 300 ° C
Detection method: Electron impact method

"Example 1"
<Production method of bis (4-methyl-2-pentyl carbonate)>
In a 2 L three-necked flask equipped with a thermometer, nitrogen inlet tube, and condenser, dimethyl carbonate (manufactured by Tokyo Chemical Industry Co., Ltd.) 431.6 g (4.8 mol), 4-methyl-2-pentanol 1308 g (12.8 mol) In addition, 3.3 g (0.05 mol) of lead oxide and a stirrer for stirring were put and immersed in an oil bath equipped with a temperature controller. While introducing nitrogen, the liquid temperature was gradually raised to about 90 ° C. to 125 ° C. and stirred for 10 hours for reaction. Dimethyl carbonate, methanol and 4-methyl-2-pentanol are removed by distillation and separation of the reaction solution under reduced pressure using a vacuum pump and a vacuum controller (Okano Seisakusho), and bis carbonate as a transparent product. About 297 g of a liquid containing (4-methyl-2-pentyl) was obtained.
The NMR analysis results are shown in FIG. 1 ( ¹ H-NMR) and FIG. 2 ( ¹³ C-NMR).
¹ H-NMR (CDCl 3) δ: 4.9-4.8 (2H, m), 1.5-1.7 (4H, m), 1.2-1.3 (8H, m), 0. 9 (12H, m), ¹³ C-NMR: 154 ppm, 72 ppm, 44 ppm, 20-24 ppm.
Elemental analysis results: C (70.5%), H (13.8%), O (15.7%)

"Example 2"
Preparation of (4-methyl-2-pentyl) phenyl carbonate from bis (4-methyl-2-pentyl) carbonate and phenol 40 g of phenol and 8 g of lead monoxide are heated at 180 ° C. for 10 hours, and the resulting water is phenol. The catalyst A was adjusted by distilling together. Bis (4-methyl-2-pentyl) carbonate 0.53 g (about 2.3 mmol), phenol 0.46 g (4.9 mmol) in a SUS tube with an inner diameter of 6 mm and a length of 50 mm that can be fixed with Swagelok at both ends Then, 8.4 mg of Catalyst A (amount such that the lead content is about 400 ppm of the total liquid amount) was charged, and the Swagelok cap was tightened and sealed. The temperature of the oil bath provided with the temperature controller was 220 ° C., and the reactor was immersed and reacted for 1.5 hours. After completion of the reaction, the reactor was taken out from the oil bath, allowed to cool, cooled to room temperature (about 22 ° C.), then the cap was opened and the reaction solution was taken out. When the reaction solution was analyzed by gas chromatography (FID detector), 2.6% by weight of carbonic acid (4-methyl-2-pentyl) phenyl and 0.03% by weight of diphenyl carbonate were obtained.

"Comparative example"
Preparation of methylphenyl carbonate from dimethyl carbonate and phenol Catalyst A was prepared by heating 40 g of phenol and 8 g of lead monoxide at 180 ° C. for 10 hours, and distilling off the produced water together with phenol. A SUS tube having an inner diameter of 6 mm and a length of 50 mm, which can be fixed with Swagelok at both ends, 0.21 g (about 2.3 mmol) of dimethyl carbonate, 0.46 g (4.9 mmol) of phenol and 8.4 mg of catalyst A (lead) The amount was about 400 ppm of the total liquid amount), and the Swagelok cap was tightened and sealed. The temperature of the oil bath provided with the temperature controller was 220 ° C., and the reactor was immersed and reacted for 1.5 hours. After completion of the reaction, the reactor was taken out from the oil bath, allowed to cool, cooled to room temperature (about 22 ° C.), then the cap was opened and the reaction solution was taken out. The reaction solution was analyzed by gas chromatography (FID detector). As a result, methylphenyl carbonate was found to be 1.4% by weight and diphenyl carbonate was found to be 0.01% by weight.

It is a NMR analysis (< ¹ > H-NMR) figure of the bis (4-methyl-2-pentyl) carbonate manufactured in Example 1 of this invention. It is a NMR analysis (< ¹³ > C-NMR) figure of the bis (4-methyl-2-pentyl) carbonate manufactured in Example 1 of this invention.

Claims (2)

Carbonate represented by the following formula (1).

  A method for producing an aromatic carbonate, comprising transesterifying the carbonate ester according to claim 1 with an aromatic hydroxy compound.

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