JPS5872544A - Manufacturing method of carbonate ester - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a legic acid ester, and more particularly to a method for producing a carbonic acid ester by reacting a formic acid ester with an N-substituted urea. Since polycarbonate is a raw material for polycarbonate, its importance has been recognized as polycarbonate has recently attracted attention as an excellent plastic.

By the way, conventional methods for producing carbonate esters include a method in which alcohol and phosgene are reacted, a method in which alcohol and carbon monoxide are reacted using a noble metal as a catalyst, and a method in which alcohol and methyl chloroformate are reacted. It is being However, these methods are not industrially satisfactory because the raw materials are highly toxic or require the use of expensive catalysts.

Also, Japanese Patent Application Laid-Open No. 55-151 related to the invention of the present inventors
According to Publication No. 540, this invention uses acetates, halides, nitrates, etc. of heavy metals such as copper, zinc, iron, cobalt, and nickel as catalysts, and uses stones and shavings or without using catalysts. This invention involves producing carbamic acid and formalde by reacting formic acid ester and urea, but this method did not yield any carbonic acid ester.

The inventors used raw materials with low toxicity and easy handling,
While continuing research to find a method for easily and industrially advantageous carbonate esters using relatively inexpensive catalysts, we are also further investigating the reaction between formate esters and N-substituted ureas. During the course of this research, he surprisingly obtained the new knowledge that carbonic acid esters are produced when a specific catalyst is used in this reaction, and based on this new knowledge, he completed the present invention.

That is, the present invention applies to periodic table 1m, lb, 1hata, Ib,
This is a method for producing a carbonic acid ester, which is characterized by reacting an acid ester with an N-substituted urea in the presence of a compound of an element of group Ia or group II, a nitrogen-containing organic compound, or a phosphorus-containing compound.

There are no particular restrictions on the formic acid ester used in the present invention, but in practice, a formic acid ester represented by the general formula (1) HCOOR is usually used.
), R represents an alkyl group, for example, an alkyl group having 1 to 8 carbon atoms per gram such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, amyl, hexyl and octyl. Among the formic acid esters of Kowara, methyl formate and ethyl formate are practically preferred.

Particularly suitable for the 7-N-substituted urea used in the present invention. In addition, in this general formula (2), k1 to R4 are hydrocarbon groups or hydrogen atoms.

Note that RR may be the same or different. The hydrocarbon group is, for example, a furkyl group or an aryl group, and the 7SOfuryl group is usually an alkyl group having 1 to 4 carbon atoms, but methyl and ethyl groups are preferred in practice. Further, the aryl group includes phenyl group, tolyl group, etc., and phenyl group is practically preferred. In addition, when R1-R4 are all mohydrogen atoms, that is, urea is excluded. Furthermore, an alkyl group and a 7-aryl group cannot be contained simultaneously in the same molecule.

Examples of N-substituted ureas include monoalkyl urea, diaryl urea, N,N-dialkyl urea, N,N-diaryl urea, N,N'-dialkyl urea, N,N'-diaryl urea, N, , N, N'-) Realkylurea, N, N
, N'-) Realyl urea, N.

N, N', N'-tetraalkylurea $ and N, N,
N'.

Examples include N'-tetraarylurea. Since the complexity of the reaction product can be reduced, the symmetric type N-
Substituted ureas are preferred1. stomach. Examples of suitable N-substituted ureas and 1.
N,N'-dialkyl urea such as N,N'-dimethylurea and N,N'-diphenylurea such as N,N'-diphenylurea.
, N'-diarylurea and other symmetric disubstituted ureas.

In the method of the present invention, the molar ratio of N-substituted urea to formic acid ester (N-substituted urea: formic acid ester) is 1:1 or more, and in practice it is usually 1:1 to 30, preferably 1; 2
~10.

The reaction temperature in the present invention may be 50 to 500°C. When the reaction temperature is lower than 50°C, the reaction rate becomes slow, and when the reaction temperature is higher than 50°C, there is an increased risk that side reactions such as polymerization and decomposition will occur together.

The preferred reaction temperature is 100-300°C.

The reaction in the present invention can also be carried out under the respective vapor pressures at the reaction temperatures of the N-substituted urea and formic acid ester used, that is, under autogenerated pressure. can be carried out in a carbon monoxide atmosphere, and for this purpose, carbon monoxide is usually introduced into the reactor before the reaction begins. /crn2G or more is charged before reacting.0 Note that -carbon oxide partial pressure is Okl
? /z2G or more, usually in the range of O to 1000 to 9/m2G, but in practice, the -carbon oxide partial pressure is O
~500 to 9/z2G is preferred. The reaction can also be carried out in an atmosphere of an inert gas such as nitrogen.

In the present invention, a solvent is not necessary, but a solvent such as, for example, an amide, ether, ketone or alcohol can be used. Typical solvents include formamide, N-methylformamide, and N-methylformamide.

N-dimethylformamide, keto/methyl ethers such as acetone and methyl ethyl ketone, ethers such as dimethyl ether and diethyl ether, and alcohols such as methanol and ethanol.

The reaction in the present invention can be carried out in any of the batch, semi-batch, and flow methods. (New edition) Volume 1, published by Sangyo Tosho Co., Ltd.) Is, Ib% Is, Ib, a compound of an element in Group 1 or ■, or a nitrogen-containing organic compound or a phosphorus-containing organic compound. Preferred elements are, for example, sodium and potassium in the Fa group, copper and silver in the Ib group, magnesium, calcium and barium in the A group, zinc and mercury in the Ib group, and compounds of these elements are not limited to 4T. For example, formate,
organic acid salts such as acetates, oxalates and naphthenates; chelate compounds such as sulfates, carbonate carboxylates and acetylacetone salts; halides and alcoholades. There is no % limit for nitrogen-containing organic compounds, but typical examples include monomethylamine, dimethylamine, trimethylamine, dimethylethylamine, triethylamine/, tri-n-propylamine,
- Amines such as propylamine and trilobylamine, aniline, alkylaniline, pyridine/,
Examples include pyrrolidine, piperidine, pyrimidine, N-alkyl substituted products thereof, and alkylpyridine.

Ru. Representative examples include trialkylphosphines such as trimethylphosphine and tributylphosphine, phosphines with substituted alkyl groups such as tris(7minoamyl)phosphine, triarylphosphines such as triphenylphosphine, and trimethylphosphite and triphenylphosphine. These catalysts can be used by being supported on a common carrier such as clay, acid clay or activated carbon.

The amount of these catalysts used is 10 units wg mo of N-substituted urea.
0.01 to 2004 F moJ per lj (141 moJ per 100 N-substituted urea unless otherwise specified)
However, it is not economically advisable to use more than necessary, and a sufficient reaction rate cannot be obtained if the amount used is too small. The amount used is 0.02-140'mg
moJ is preferred, and moJ of 0.05 to 100 is particularly preferred.

In the present invention, in addition to vertical acid esters, carnoeric acid esters and formamides are co-produced, but these can be separated from each other by a convenient means such as distillation.
Both L and Kamo have high utility value, so there is no need to consider them at all.

That is, carbamate esters are heavily used in the medical field and are used in large quantities as raw materials for urethane, while formamides are not only excellent solvents but have recently attracted particular attention as intermediate raw materials in the chemical industry. Formamides are also used as solvents in the reaction of the present invention.

The carbonate ester, carbamate ester, and formamide obtained in the present invention are of the general formula (1) and the general formula (
When using the compounds shown in 2),
General formula (31, general formula (4) and general formula (5) below)
4 are shown respectively. That is, general formula (3) RO・CO・OR In addition, R and 几～B in these general formulas (3) to (5) are respectively represented by the above general formula (11) and -general formula (
This is the same as in 2).

In the present invention, all raw materials are low in toxicity and easy to handle, the catalyst is relatively inexpensive, and the carbonate ester is industrially advantageous and easily obtained, and can be co-produced. - Rubamic acid esters and formamides also 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 In a Hastelloy CM autoclave with an internal volume of 100 cc,
N, N'-dimethylurea 111.22■mo4
% formic acid ester and a catalyst and the lid is closed, the air inside the autoclave is replaced with carbon monoxide or nitrogen, or after the replacement, carbon oxide or nitrogen is filled up to the specified pressure, and the autoclave is heated to the specified temperature. was allowed to react 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.

Example 13 N in a Hastelloy C autoclave with an internal volume of 100 cc.
, N'-dimethylurea 111.22 ■moA s
Methyl formate 556,76■ moth iron acetylacetonate 1, 411 & 9 molJ and N.

N-dimethylform7mide 80,09Qmo-g was charged, the lid was closed, and the air inside was replaced with carbon oxide. Then - fill 56 with carbon oxide to 9/cm2G,
The reaction was carried out at 175°C for 1 hour.

After cooling, the gas inside the autoclave is purged and returned to normal pressure, and the reaction product is taken out and placed on the gas chromatograph 1.
This was analyzed further. As a result, methyl N-methyl rubamate is 85.67 mO!
-■■■■Example 14 N in a Hastelloy C autoclave with an internal volume of 100cc
, N'-diphenylurea 50,66w1010-
e% methyl formate 335.48qmo & acetate steel
1.26 straw gmo and acetone 160°76q
Charge mo13, cover the container, and replace the air inside with carbon oxide. Then, 55 was filled with carbon oxide to 9/2G and reacted at 175°C for 7 hours. 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 result is that methyl N-phenylcarbamate is 33.2
Example: 6 mo, dimethyl acid was 4.04 m0AII, and formanilide was 41.88 qmoAll.
15 N in a Hastelloy C autoclave with an internal volume of 100 cc.
, N-dimethylurea 111.22111Imo13s
Methyl formate 536.28s9mo-# and zinc acetate 5.63m9moR were charged, the lid was closed, and the air inside was replaced with carbon oxide.
It was filled to a volume of cm2G and reacted at 17℃ for 5 hours.

After cooling, the gas in the autoclave was purged to return to normal pressure, and the reaction product was taken out and analyzed using a gas chromatograph. As a result, formamide was 10.38 μmol
b, 91■■■■■I■■Dimethyl carbonate is 2゜68■
mo-6,11111 ■■■■■l 11 methyl minzaate 54.23 mo 9 mol-■■■■
■■l is 57.24mgmo134■■■■■■■■1
generated.

Example 16 N in a Hastelloy C autoclave with an internal volume of 100 oc.
, N-dimethylurea 111.22 gmo-e, methyl formate 335.81119 moA and triethylamine 11.76 m9 mo13 were charged, the lid was closed and the air inside was replaced with nitrogen, and then the nitrogen was adjusted to 56 #/crn.
It was filled up to 2G and reacted at 175°C for 5 hours. After cooling,
After purging the gas in the autoclave and returning it to normal pressure, react the mob, III■I■■11-membered acid dimethyJ
Shiga2゜57 Ml moJ%1■■■■■■I■-Methicarbamate JL, is 49.66■malt-■■■
■■■I-■- and N,N'-dimethylformamide were produced at 54.57■ mob-■■■■■■Onkaku■-.

Patent applicant: Mitsubishi Gas Chemical Co., Ltd. Representative wear Kazuyoshi Nagano −3σ

Claims (1)

[Claims] Periodic Table 11, Ib, a1 Seal *%l1mProcess for producing carbonic ester, characterized by reacting acid ester with N-substituted urea