JP2011032222A - Process for producing cyclic carbonate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a process for producing a cyclic carbonate in a high yield by a reaction even at about normal temperature and normal pressure. <P>SOLUTION: The process comprises the production of a cyclic carbonate by the reaction of an epoxy compound with carbon dioxide. The reaction is carried out in the presence of an indium or organophosphorus catalyst. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a novel method for producing a cyclic carbonate.

  Cyclic carbonates (cyclic carbonates) such as ethylene carbonate, propylene carbonate, and butylene carbonate are widely used as electrolytes, plastic raw materials, solvents, and the like for lithium ion secondary batteries.

  Conventionally, various methods for producing cyclic carbonates have been proposed. For example, a production method in which an ammonium salt is used as a catalyst and reacted under high temperature and high pressure is known. Patent Document 1 uses at least one of 3-octahedral smectite and / or alkali metal-containing 3-octahedral smectite as a catalyst in a method for producing alkylene carbonate by reaction of an epoxy compound and carbon dioxide. A manufacturing method is described.

  The production method of Patent Document 1 basically requires a reaction at a high temperature. On the other hand, Patent Document 2 describes that in a method for producing a cyclic carbonate by a reaction between an epoxy compound and carbon dioxide, the reaction conditions are alleviated by using an indium catalyst and a tin catalyst together. . However, Patent Document 2 describes that a cyclic carbonate can be obtained by a reaction near room temperature, but in order to obtain a desirable yield, the pressure of carbon dioxide needs to be several tens of atmospheres. .

  In order to further relax the reaction conditions, various catalysts for producing cyclic carbonates have been developed (Patent Documents 3, 4, etc.). For example, Patent Literature 3 describes a cyclic carbonate production catalyst containing an onium salt compound and mesoporous silica.

  From the viewpoint of energy saving, it is desired that a cyclic carbonate can be produced with high efficiency by a reaction near room temperature and normal pressure. However, at present, no such production method has been developed.

JP 2003-96074 A JP 2006-151891 A JP 2007-209926 A JP 2008-189608 A

  The main object of the present invention is to provide a method capable of producing a cyclic carbonate in a high yield even in a reaction near normal temperature and pressure.

  As a result of repeated studies in view of the problems of the prior art, the present inventor has found that the above object can be achieved by employing a catalyst in a specific combination, and has completed the present invention.

That is, this invention concerns on the manufacturing method of the cyclic carbonate shown below.
1. A method for producing a cyclic carbonate by reacting an epoxy compound with carbon dioxide, wherein the reaction is carried out in the presence of an indium catalyst and an organophosphorus catalyst.
2. The manufacturing method according to Item 1, wherein the indium-based catalyst is at least one of indium halide InX ₃ (where X represents a halogen atom).
3. The manufacturing method according to Item 1, wherein the indium-based catalyst is at least one of InBr ₃ and InI ₃ .
4). The manufacturing method according to any one of Items 1 to 3, wherein the organophosphorus catalyst is at least one of phosphines.
5). Item 4. The method according to any one of Items 1 to 3, wherein the organophosphorus catalyst is at least one selected from the group consisting of triphenylphosphine, tricyclohexylphosphine, and tributylphosphine.
6). The epoxy compound is represented by the following formula (1);

(However, R ^{1 to} R ⁴ are the same as or different from each other, and each represents a hydrogen atom, an alkyl group, or an aromatic hydrocarbon group that may have a substituent.)
A compound represented by
The cyclic carbonate is represented by the following formula (2);

(However, R ^{1 to} R ⁴ are the same as or different from each other, and each represents a hydrogen atom, an alkyl group, or an aromatic hydrocarbon group that may have a substituent.)
The manufacturing method in any one of said claim | item 1-5 which is a compound shown by these.
7). Item 7. The production method according to any one of Items 1 to 6, wherein the reaction is performed at a temperature of 100 ° C or lower.
8). Item 7. The production method according to any one of Items 1 to 6, wherein the reaction is performed at a temperature of 30 ° C or lower.
9. Item 9. The production method according to any one of Items 1 to 8, wherein the reaction is performed in the absence of a solvent.

  According to the production method of the present invention, a cyclic carbonate is produced in a high yield from an epoxy compound under a milder condition (preferably near normal temperature and normal pressure) by using an indium catalyst and an organophosphorus catalyst in combination as a catalyst. be able to.

  The production method of the present invention is a method for producing a cyclic carbonate by a reaction between an epoxy compound and carbon dioxide, wherein the reaction is carried out in the presence of an indium catalyst and an organophosphorus catalyst.

  As a starting material, an epoxy compound which may have a substituent and carbon dioxide are used.

  More specifically, the epoxy compound is represented by the following formula (1).

(However, R ^{1 to} R ⁴ are the same as or different from each other, and each represents a hydrogen atom, an alkyl group, or an aromatic hydrocarbon group that may have a substituent.)
The compound shown by can be used suitably.

  Although it does not specifically limit as an alkyl group, For example, C1-C10 alkyl groups, such as a methyl group, an ethyl group, a propyl group, a butyl group, are especially preferable. More preferably, it is a C4-C8 alkyl group (from a butyl group to an octyl group).

  The alkyl group may have a substituent. Examples of the substituent include various substituents such as methyl group, ethyl group, phenyl group, ether group, nitro group, sulfo group, amide group, amino group, carboxyl group, halogen group, hydroxy group, and ester group. .

  Examples of the aromatic hydrocarbon group include a phenyl group, a tolyl group, a xylyl group, and a mesityl group.

  The aromatic hydrocarbon group may have a substituent. Examples of the substituent include the various substituents mentioned above.

In the present invention, depending on the R ¹ to R ^4, cyclic carbonate to obtain the corresponding.

  That is, the following formula (2);

(However, R ^{1 to} R ⁴ are the same as or different from each other, and each represents a hydrogen atom, an alkyl group, or an aromatic hydrocarbon group that may have a substituent.)
Can be obtained. Accordingly, the R ^{1 to} R ⁴ of the epoxy compound as a starting material may be appropriately selected according to the type of the target cyclic carbonate. In particular, in the present invention, it is preferable that at least 1 to 2 of R ^{1 to} R ⁴ are hydrogen atoms.

  In the present invention, particularly by using propylene oxide, epichlorohydrin, methyl glycidyl ether, vinyl oxirane, methacrylic acid glycidyl ester, etc. as an epoxy compound, it is possible to suitably produce a cyclic carbonate in which an oxirane ring and carbon dioxide are reacted. it can.

  Carbon dioxide may be used in an equivalent amount or more that reacts with the epoxy compound used. In general, carbon dioxide may be introduced into the reaction system so that the partial pressure of carbon dioxide is 1 to 60 atm, preferably 1 to 50 atm. In the production method of the present invention, in a preferred embodiment, the cyclic carbonate can be produced near normal pressure. In the case of the vicinity of normal pressure, it is preferably 1 to 10 atm, more preferably 1 to 5 atm.

  The production method of the present invention is carried out in the presence of an indium catalyst and an organophosphorus catalyst. That is, the reaction is performed under conditions of a mixed system of both catalysts. This makes it possible to obtain a cyclic carbonate in a high yield even in a mild reaction near normal temperature and pressure. If the organophosphorus catalyst is missing, the epoxy compound is ring-opened, and as a result, a polymer is formed by the polymerization reaction. Further, when the indium catalyst is missing, the reaction does not proceed. Therefore, when either one is missing, the target product cannot be obtained.

The indium-based catalyst can be appropriately selected from indium metal or an indium compound. In the present invention, it is particularly desirable to use at least one of indium halide InX ₃ (where X represents a halogen atom). Among these, at least one of InBr ₃ and InI ₃ is preferable, and InBr ₃ is more preferable.

  The form of the indium-based catalyst is not limited, but can be generally used in the form of particles (powder). The particle size in this case is not particularly limited, but in general, it may be appropriately set within a range of an average particle size of about 10 to 200 μm. Further, if necessary, it can be appropriately supported on a known carrier such as alumina, silica, zirconia, activated carbon and the like.

  The amount of the indium-based catalyst used can be appropriately set according to the type of indium-based catalyst used, the type of epoxy compound used, etc., but is generally about 0.01 to 10 mol% with respect to the epoxy compound. In particular, 0.1 to 5 mol% is desirable.

The organophosphorus catalyst is not limited, but phosphines are particularly desirable. Examples of phosphines include tricyclohexylphosphine, tributylphosphine, trioctylphosphine, cyclohexyldiphenylphosphine, dicyclohexylphenylphosphine, butyldiphenylphosphine, dibutylphenylphosphine, octyldiphenylphosphine, and dioctylphenylphosphine. Examples thereof include phosphines having a group bonded thereto. Also, tris- (p-methoxyphenyl) phosphine, tris- (o-methoxyphenyl) phosphine, tris- (m-methoxyphenyl) phosphine, tri-p-tolylphosphine, tri-o-tolylphosphine, tri-m- Tolylphosphine, bis- (p-methoxyphenyl) phenylphosphine, bis- (o-methoxyphenyl) phenylphosphine, bis- (m-methoxyphenyl) phenylphosphine, di-p-tolylphenylphosphine, di-o-tolylphenyl Phosphine, di-m-tolylphenylphosphine, diphenyl (p-methoxyphenyl) phosphine, diphenyl (o-methoxyphenyl) phosphine, diphenyl (m-methoxyphenyl) phosphine, diphenyl-p-tolylphosphine, diphenyl-o-tri Phosphine, diphenyl -m- tolyl phosphine, triaryl phosphines such as triphenyl phosphine. Among these phosphines, at least one of triphenylphosphine (Ph ₃ P), tricyclohexylphosphine (Cy ₃ P), and tributylphosphine (Bu ₃ P) is particularly preferable.

  Although the form of the organophosphorus catalyst is not limited, it can usually be used in a liquid or granular (powdered) form. The particle size in this case is not particularly limited. Further, if necessary, it can be appropriately supported on a known carrier such as alumina, silica, zirconia, activated carbon and the like.

  The amount of the organophosphorus catalyst used can be appropriately set according to the type of the organophosphorus catalyst used, the type of the epoxy compound used, and the like. %, Particularly 0.2 to 10 mol% is desirable.

  Further, the use ratio of the indium-based catalyst and the organic phosphorus-based catalyst is not particularly limited, but in general, the molar ratio of indium-based catalyst: organic phosphorus-based catalyst is preferably about 1: 1 to 3, and about 1: 2. More preferred.

  The reaction phase may be any of a liquid phase reaction, a gas phase reaction, a liquid phase-gas phase, and the like. In general, the production method of the present invention is a two-phase or three-phase reaction because carbon dioxide is a gas phase among the starting materials and the others are a liquid phase or a solid phase.

  In the present invention, raw materials other than carbon dioxide (especially epoxy compounds and catalysts) can be dissolved or dispersed in a solvent. As a solvent, it can determine suitably according to the kind etc. of epoxy compound to be used. In particular, in the present invention, for example, polar solvents (particularly aprotic polar solvents) such as dimethyl sulfoxide (DMSO), N, N-dimethylformamide (DMF), acetonitrile and tetrahydrofuran, and nonpolar solvents such as benzene and hexane are suitable. Can be used. When using a solvent, the concentration of the epoxy compound or the like can be adjusted as appropriate. In the present invention, the reaction can be allowed to proceed without a solvent, and in this case, a cyclic carbonate can be obtained in a shorter time than when a solvent is used.

  The reaction format is appropriately selected from known reaction formats such as continuous, batch, and semi-batch. Further, the catalyst contact method is not limited, and any of a fixed bed, a fluidized bed, a suspension bed and the like can be employed.

  Regarding the reaction conditions, the reaction temperature is not limited, but it can usually be appropriately adjusted within a range of 100 ° C. or less. In particular, in the present invention, a cyclic carbonate can be produced in a desired yield even at 30 ° C. or lower. The lower limit of the reaction temperature may be appropriately determined usually within a range of 0 ° C. or higher. The reaction atmosphere is preferably a carbon dioxide-containing atmosphere, and the carbon dioxide partial pressure is preferably set within the pressure range. In the present invention, in a preferred embodiment, a cyclic carbonate can be produced in a high yield by a reaction near normal temperature and pressure. The reaction time can be appropriately changed depending on the reaction temperature and the like, but it is usually about 5 to 12 hours at room temperature, and the reaction can be proceeded in a shorter time (about 1 to 5 hours) particularly in the absence of a solvent.

  After completion of the reaction, if necessary, the reaction product is purified (extraction, distillation, etc.), separated (centrifugation, filtration, etc.) by a known method and then the target cyclic carbonate is recovered. good.

  The present invention will be specifically described below with reference to examples. However, the present invention is not limited to the examples.

  In the following examples, a cyclic carbonate was produced according to the following reaction.

Examples 1 to 11 (normal temperature and normal pressure)
An epoxy compound (10 mmol), an indium catalyst (Cat-a: InBr ₃ 5 mmol), and an organophosphorus catalyst (Cat-b: PPh ₃ ) in a glass container (capacity 50 cm ³ ) containing a magnetic rotor without solvent. 10 mmol) was added, and a rubber balloon filled with carbon dioxide at 1 atm was connected, followed by stirring reaction at room temperature and normal pressure (20 ° C., 1 atm).

Next, the content after the reaction was taken out by adding diethyl ether and water, and further etherified by adding water and diethyl ether. The component obtained by drying the ether phase with magnesium sulfate and then concentrating was treated by silica gel column chromatography to obtain the desired product with ethyl acetate. After the ethyl acetate was distilled off under reduced pressure, the yield of the main product was determined by ¹ H-NMR. Furthermore, the product was isolated and purified by distillation. The target product was identified by ¹ H-NMR, ¹³ C-NMR and IR. As a result, the target cyclic carbonate was obtained.

  The substituent R, reaction time, and yield of the desired product are shown in Table 1 below.

  As is clear from the results in Table 1, in all of Examples 1 to 11, it can be seen that cyclic carbonates can be obtained from epoxy compounds at normal temperature and pressure. Moreover, it turns out that a cyclic carbonate is obtained with the high yield exceeding 80% in some Examples. Even when using an epoxy compound, a vinyl epoxide, or a glycidyl methacrylate ester having an electron-withdrawing substituent that has a poor reaction or does not proceed when a conventional indium-tin catalyst is used, the production method of the present invention is applicable. Thus, a cyclic carbonate can be easily obtained.

For reference, in Example 8, when the carbon dioxide pressure was changed to 40 atmospheres (using a 50 cm ³ autoclave made of SUS32 as a reaction vessel), the yield was 96% in only 1 hour. In the production method of the present invention, the target cyclic carbonate can be obtained even at room temperature and normal pressure as described above. However, when pressure is applied, a high yield can be achieved in a shorter time.

Examples 12 to 13 (comparison of indium catalysts at room temperature and 40 atm)
In an autoclave (made of SUS32, volume 50 cm ³ ) containing a magnetic rotor, acetonitrile (3 ml), epoxy compound (10 mmol), indium catalyst (Cat-a: 5 mmol) and organophosphorus catalyst (Cat-b: 10 mmol) And filled with 40 atm carbon dioxide, and stirred at room temperature (20 ° C.).

  The method for purification and identification of the target product was the same as in Examples 1-11. Thereby, the target cyclic carbonate was obtained.

  The substituent R, indium catalyst, organophosphorus catalyst, reaction time, and yield of the target product are shown in Table 2 below.

As is apparent from the results in Table 2, it can be seen that the target cyclic carbonate is obtained in any of Examples 12 and 13. When the same organophosphorus catalyst is used, it can be seen that InBr ₃ has a slightly higher yield than InI ₃ as the indium catalyst. As a reference, when the reaction was carried out without using either Cat-a or Cat-b, the yield was almost 0%.

Examples 14 to 18 (Comparison of solvents at room temperature and 40 atm)
A cyclic carbonate was produced in the same manner as in Example 13 except that the solvent was changed from acetonitrile. Table 3 below shows the types and yields of the solvents.

  As is clear from the results in Table 3, it can be seen that the target cyclic carbonate can be obtained in any of Examples 14 to 18. When a conventional indium-tin catalyst is used, a sufficient yield cannot be obtained with a solvent other than acetonitrile, but it can be seen that the production method of the present invention can produce a cyclic carbonate using various solvents. The best yield was obtained in Example 18 without solvent.

Examples 19 to 20 (comparison of organophosphorus catalysts at room temperature and 40 atm)
A cyclic carbonate was produced in the same manner as in Example 14 except that the organophosphorus catalyst was changed from Ph ₃ P. The type and yield of the solvent are shown in Table 4 below.

As is apparent from the results in Table 4, it can be seen that the target cyclic carbonate is obtained in any of Examples 19 to 20. When the same indium-based catalyst is used, it can be seen that Ph ₃ P has a higher yield than Cy ₃ P or Bu ₃ P as the organophosphorus catalyst.

Claims (9)

  A method for producing a cyclic carbonate by reacting an epoxy compound with carbon dioxide, wherein the reaction is carried out in the presence of an indium catalyst and an organophosphorus catalyst. The manufacturing method according to claim 1, wherein the indium-based catalyst is at least one of indium halide InX ₃ (where X represents a halogen atom). The manufacturing method according to claim 1, wherein the indium-based catalyst is at least one of InBr ₃ and InI ₃ .   The said organic phosphorus catalyst is a manufacturing method in any one of Claims 1-3 which is at least 1 sort (s) of phosphines.   The said organophosphorus catalyst is a manufacturing method in any one of Claims 1-3 which is at least 1 sort (s) selected from the group which consists of triphenylphosphine, tricyclohexylphosphine, and tributylphosphine. The epoxy compound is represented by the following formula (1);

(However, R ^{1 to} R ⁴ are the same as or different from each other, and each represents a hydrogen atom, an alkyl group, or an aromatic hydrocarbon group that may have a substituent.)
A compound represented by
The cyclic carbonate is represented by the following formula (2);

(However, R ^{1 to} R ⁴ are the same as or different from each other, and each represents a hydrogen atom, an alkyl group, or an aromatic hydrocarbon group that may have a substituent.)
The manufacturing method in any one of Claims 1-5 which is a compound shown by these.   The manufacturing method in any one of Claims 1-6 which performs the said reaction under the temperature of 100 degrees C or less.   The manufacturing method in any one of Claims 1-6 which performs the said reaction under the temperature of 30 degrees C or less.   The production method according to claim 1, wherein the reaction is performed in the absence of a solvent.