JPH0237907B2 - TANSANESUTERUNOSEIZOHOHO - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a carbonic ester, and more particularly, to a method for producing a carbonic ester by reacting carbon monoxide with an alcohol and/or a formic ester with urea or N-substituted urea. Since carbonate ester is a raw material for polycarbonate, for example, its importance has been recognized as polycarbonate has attracted attention as an excellent plastic. By the way, conventional methods for producing carbonate ester include a method of reacting alcohol and phosgene;
A method of reacting an alcohol with carbon monoxide using a noble metal as a catalyst, a method of reacting an alcohol with methyl chloroformate, etc. are known. However, these methods are not industrially satisfactory because the raw materials are highly toxic or require the use of expensive catalysts. In addition, Japanese Patent Application Laid-Open No. 1986-55 related to the invention of the present inventors
In Publication No. 15154, formic acid ester and urea are
Carbamate esters and formamide are produced by reacting heavy metals such as copper, zinc, iron, cobalt, and nickel with their respective acetates, halides, and nitrates as catalysts or without using catalysts. However, in this invention, no carbonate ester was obtained at all. The present inventors have conducted extensive research to find a method for industrially advantageous and easy production of carbonate esters using inexpensive raw materials and catalysts, and have found that formate esters and urea or N-substituted He discovered that carbonic acid esters can be obtained efficiently by reacting with urea using a specific catalyst, and based on this new fact, he completed his invention and published Japanese Patent Application No. 177952-1983 (Japanese Patent Application No. 140145-1983). (see official bulletin)
has been applied for. The invention of this Japanese Patent Application No. 177952/1986 is based on the combination of formic acid ester and urea or N-substituted urea (a) b, a, b, b, a, b of the periodic table.
Production of a carbonate ester, characterized in that the reaction is carried out in the presence of a compound of an element of group a, group a, or an element of actinide group, and (b) a nitrogen-containing organic compound, a phosphorus-containing organic compound, or an organic compound of group a element. It is the law. As a result of further intensive studies aimed at improving this earlier invention, the present inventors discovered that by further adding an epoxide to the reaction system in this earlier invention, the reaction temperature was 30°C or more lower than that in the earlier invention. Moreover, we obtained new knowledge that the reaction proceeds smoothly even in a short period of time, and that carbonic acid esters can be produced industrially advantageously even when carbon monoxide and alcohol are used as raw materials. Based on this new knowledge, we I have made this discovery. That is, the present invention combines (i) carbon monoxide, alcohol and/or formate, (ii) urea and/or N-substituted urea, (a) epoxide, and (b)
Periodic table b, a, b, b, a, b,
(c) a nitrogen-containing organic compound, a phosphorus-containing organic compound, or an organic compound of a group a element (hereinafter referred to as the second component); ) is a method for producing a carbonate ester, characterized in that the reaction is carried out in the presence of a carbonic acid ester. The alcohol used in the present invention is not particularly limited, but in practice it is usually an aliphatic alcohol represented by the general formula (1) ROH. In addition, in this general formula (1), R represents an alkyl group, such as methyl, ethyl, propyl, isopropyl, butyl,
It is an alkyl group having 1 to 8 carbon atoms such as isobutyl, tert-butyl, amyl, hexyl and octyl. Among these alcohols, methanol and ethanol are practically preferred. Although the carbon monoxide used in the present invention may contain small amounts of other gases such as hydrogen, carbon dioxide, nitrogen, neon, helium, and argon, it is preferable that the content of organic compounds be as low as possible. There are no particular restrictions on the formic acid ester used in the present invention, but in practice, it is usually represented by the general formula (2).
Formate esters designated HCOOR are used.
In addition, R in general formula (1) in this general formula (2)
It is similar to That is, R is, for example, methyl,
It is an alkyl group having 1 to 8 carbon atoms such as ethyl, propyl, isopropyl, butyl, tert-butyl, amyl, hexyl and octyl. Note that the formic acid ester is selected so that its alkyl group is the same as the alcohol used. Among these formic acid esters, methyl formate or ethyl formate is practically preferred. In addition to urea, N-substituted ureas are used in the present invention. Although there are no particular limitations on the N-substituted urea used in the present invention, practically,
Usually general formula (3)

An N-substituted urea of the formula is used. Furthermore, this general formula
In (3), R ¹ to ^{R 4} are a hydrocarbon group or a hydrogen atom. Note that R ¹ to R ⁴ may be the same or different. Examples of the hydrocarbon group include an alkyl group or an aryl group. The alkyl group is usually an alkyl group having 1 to 4 carbon atoms, but from a practical standpoint, methyl group, ethyl group, etc. are preferable. Further, the aryl group includes a phenyl group, a tolyl group, and the like, and a phenyl group is practically preferred. Note that cases where all R ¹ to ^{R 4} are hydrogen atoms are excluded. Furthermore, an alkyl group and an aryl group cannot be contained simultaneously in the same molecule.
Examples of N-substituted ureas include monoalkylureas,
Monoarylurea, N,N-dialkyl urea,
N,N-diarylurea, N,N'-dialkylurea, N,N'-diarylurea, N,N,N'-
Examples include trialkylurea, N,N,N'-triarylurea, N,N,N',N'-tetraalkylurea and N,N-N',N'-tetraalkylurea. Urea and symmetric N-substituted ureas are preferred to reduce the complexity of the reaction product. Suitable N-substituted ureas include symmetrical disubstituted ureas such as N,N'-dialkyl ureas such as N,N'-dimethylurea and N,N'-diarylureas such as N,N'-diphenylurea. can be mentioned. In the method of the present invention, urea or N-substituted urea (hereinafter both may be collectively referred to as ureas)
The molar ratio of formic acid ester or alcohol to
Preferably it is 2-10. In the present invention, the reaction is carried out in the presence of an epoxide, but the epoxide is not particularly limited as long as it is a compound having an epoxy group. For example, ethylene oxide, propylene oxide, and styrene oxide are representative examples.
Practically, propylene oxide is preferably used. The amount of epoxide added is 1 to 1000 mol per 100 mol of formic acid ester or alcohol, but usually 5 to 500 mol, preferably 10 to 200 mol.
It is a mole. The reaction temperature in the present invention is 50 to 400°C. When the reaction temperature is lower than 50°C, the reaction rate is slow, and when the reaction temperature is higher than 400°C, there is an increased risk that side reactions such as polymerization and decomposition will occur simultaneously. The preferred reaction temperature is 100-200°C. When a formic acid ester and a urea are used, the reaction in the present invention can also be carried out under the respective vapor pressures at the reaction temperatures of the urea and formic acid ester used, that is, under self-generating power. Further, in order to suppress the decomposition of the formate ester, the reaction can be carried out in a carbon monoxide atmosphere, and for this purpose, carbon monoxide is usually charged at 0 kg/cm ² G or more prior to the reaction. The carbon monoxide partial pressure is 0.
Kg/cm ² G or more, usually in the range of 0 to 1000 Kg/cm ² G, but it is impractical to use higher pressure than necessary, so the carbon monoxide partial pressure should be 0 to 500 Kg/cm ² G.
is preferred. The reaction can also be carried out under an atmosphere of an inert gas such as nitrogen. In the present invention, when carbon monoxide, alcohol and ureas are used as raw materials, the reaction is carried out under pressure of carbon monoxide. Carbon monoxide partial pressure is 0Kg/
cm ² G or more, usually in the range of 0 to 1000 Kg/cm ² G, but since higher pressure than necessary is not practical, the carbon monoxide partial pressure is preferably 0 to 500 Kg/cm ² G. In the present invention, a solvent is not necessary, but it is possible to use a solvent such as, for example, an amide, ether, ketone or alcohol. Typical solvents include amides such as formamide, N-methylformamide, and N,N-dimethylformamide, ketones such as acetone and methyl ethyl ketone, ethers dimethyl ether, diethyl ether, and diphenyl ether, and alcohols such as methanol and ethanol. can be given. When using alcohol as a solvent, use the same alcohol as the raw material or the same alkyl group as the formate ester.
Preference is given to using an alcohol consisting of OH. The reaction in the present invention can be carried out by any of the batch, semi-batch and flow methods. The catalyst in the present invention contains a first component and a second component. The first component of the catalyst used in the present invention is the periodic table (however, the periodic table is according to Toshizo Chiya, Inorganic Chemistry (New Edition) Volume 1, published by Sangyo Tosho).
b, a, b, b, a, b, a,
a, a compound of a group element or a compound of an actinide group element. Preferred elements are, for example, copper and silver for group B, magnesium for group a,
calcium and barium, zinc and mercury in group b, boron and aluminum in group b;
Zirconium in the a group, silicon, tin and lead in the b group, chromium, molybodene and tungsten in the a group, manganese and rhenium in the a group, iron, cobalt, nickel and palladium in the group a, and thorium, uranium, etc. in the actinide group. be. There are no particular restrictions on the compounds of these elements, but
For example, organic acid salts such as formates, acetates, oxalates and naphthenates, inorganic acid salts such as sulfates, nitrates and carbonates, chelate compounds such as polyaminocarboxylate and acetylacetone salts, halides. and carbonyl compounds. Mixtures of the compounds of the first component can also be used. The second component of the catalyst used in the present invention is a nitrogen-containing organic compound, a phosphorus-containing organic compound, or an organic compound of a group a element. There are no particular restrictions on nitrogen-containing organic compounds, but typical examples include monomethylamine, dimethylamine,
Amines such as trimethylamine, dimethylethylamine, triethylamine, tri-n-propylamine, tri-iso-propylamine and tri-n-butylamine, aniline, alkylanilines, pyridine, pyrrolidine, piperidine, pyrimidine and their N-alkyl These include substituted products and alkylpyridines such as picoline. Although there are no particular limitations on the phosphorus-containing organic compound, trivalent phosphorus organic compounds are generally used in practice. Representative examples include trialkylphosphines such as trimethylphosphine and tributylphosphine, phosphines with an alkyl group such as tris(aminoamyl)phosphine, triarylphosphines such as triphenylphosphine, and trimethylphosphine, trimethylphosphine, etc. Mention may be made of phosphites such as butyl phosphite and triphenyl phosphite. There are no particular limitations on the compound of the group a element, but organic compounds of sodium and potassium, such as sodium alcoholate and potassium alcoholate, are preferably used.
Mixtures of compounds of the second component can also be used. These catalyst component compounds can also be used by being supported on a conventional carrier such as clay, acid clay or activated carbon. The amount of the first component of the catalyst to be used can be selected within the range of 0.01 mol or more per 100 mol of urea, preferably 0.01 to 100 mol (hereinafter expressed in mol per 100 mol of urea unless otherwise specified). However, it is not economically advisable to use more than 100 mol, and if the amount used is less than 0.01 mol, a sufficient reaction rate cannot be obtained. The amount of the first component of the catalyst used is particularly preferably 0.02 to 70 mol,
Most preferred is 0.05-50 moles. The amount of the second component of the catalyst to be used can be selected within the range of 0.01 to 100 moles per 100 moles of urea (hereinafter expressed in moles per 100 moles of urea unless otherwise specified). However, although it is possible to use more than 100 mol, it is not economically advantageous, and if the amount used is less than 0.01 mol, a sufficient reaction rate cannot be obtained. The amount of the second component of the catalyst used is
0.02 to 70 mol is preferred, and 0.05 to 50 mol is particularly preferred. In the present invention, carbamate esters and formamides are co-produced in addition to carbon esters, but these can be separated from each other by simple means such as distillation, and both have high utility value. It's not worth considering. In other words, carbamate esters are heavily used in the medical field and are also used in large quantities as raw materials for urethane.
On the other hand, formamides are not only excellent solvents, but have also recently attracted particular attention as intermediate raw materials in the chemical industry. Formamides also act as a solvent in the reaction of the present invention. When the compounds represented by the above general formulas (1), (2) and general formula (3) are used as the raw materials formate ester and N-substituted urea, the carbonate ester, carbamate ester and formamide, respectively, are as follows. It is represented by general formula (4), general formula (5) and general formula (6). That is, General formula (4) RO・CO・CR General formula (5)

[expression] and

【formula】 as well as General formula (6)

[expression] and

[Formula] In addition, R and in these general formulas (4) to (6)
R ¹ to ^{R 3} are the same as in the above general formulas (1), (2) and general formula (3), respectively. Note that when urea is used, R ¹ to R ⁴ in the above general formulas (5) and (6) all become hydrogen atoms. In the present invention, all raw materials are easy to handle, the catalyst is relatively inexpensive, carbonate esters can be easily obtained industrially, and carbamate esters are co-produced. and formamides have high utility value, and the industrial value of the present invention is extremely high. Next, the present invention will be explained in more detail with reference to Examples. Examples 1 to 12 Into a Hastelloy C autoclave with an internal volume of 100 c.c., ureas, formic acid esters, catalysts (first and second components), and epoxides, as well as predetermined amounts of solvents as necessary, were charged. After closing the autoclave, the air in the autoclave was replaced with carbon monoxide or nitrogen, or after the replacement, carbon monoxide or nitrogen was filled up to a predetermined pressure, and the autoclave was reacted at a predetermined temperature for a predetermined time. After cooling, the gas in the autoclave was purged to return to normal pressure, and the reaction product was taken out and analyzed by gas chromatography. The conditions and results are summarized in Table 1.

【table】

【table】

[Table] Examples 13 to 23 Into a Hastelloy C autoclave with an internal volume of 100 c.c., predetermined amounts of urea, alcohol, catalyst (first component, second component), epoxide, and solvent as necessary are added. After charging the autoclave and closing the lid, the air in the autoclave was replaced with carbon monoxide, then carbon monoxide was filled to a predetermined pressure, and the autoclave was reacted at a predetermined temperature for a predetermined time. After cooling, the gas in the autoclave was purged to return it to normal pressure, and the reaction product was taken out and analyzed by gas chromatography. The conditions and results are summarized in Table 2.

【table】

[Table] Example 24 99.99 mgmol of N,N'-dimethylurea was added to a Hastelloy C autoclave having an internal volume of 100 c.c.
Methanol 437.02mgmol, propylene oxide
73.56mgmol, iron acetylacetonate 3.91mg
mol, N-Methylpyrrolidine 5.15mgmol, methyl formate 171.81mgmol, cover the lid, replace the internal air with carbon monoxide, and then remove carbon monoxide to 145mgmol.
Kg/cm ² G was charged and the reaction was carried out at 130°C for 4 hours.
The product after the reaction contains 34.73 mgmol of dimethyl carbonate,
It contained 53.07 mgmol of methyl N-methylcarbamate and 121.80 mgmol of N-methylformamide. Example 25 In the same autoclave as in Example 24, 99.99 mgmol of N,N'-dimethylurea and 430.28 mg of ethanol were added.
mol, propylene oxide 73.41 mgmol, iron acetylacetonate 3.91 mgmol, tri-n-butylphosphine 4.80 mgmol, ethyl formate 170.53 mgmol, N
-Methylformamide 34.91mgmol, carbon monoxide
Each tube was filled with 148 Kg/cm ² G and reacted at 130° C. for 4 hours. The product after the reaction is diethyl carbonate.
30.80mgmol, ethyl N-methylcarbamate
It contained 57.48 mgmol and 117.94 mgmol of N-methylformamide (the amount produced in the reaction).

Claims (1)

[Claims] 1 (i) carbon monoxide and alcohol and/or formate ester and (ii) urea and/or N-substituted urea, (a) epoxide and (b) periodic table b,
Reaction in the presence of a, b, b, a, b, a, a, a, or group element compound or actinide group element compound and (c) a nitrogen-containing organic compound, a phosphorus-containing organic compound, or an organic compound of a group a element. A method for producing a carbonate ester, characterized by: