JPS6056697B2 - Method for producing glycerin esters - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel method for producing glycerin esters corresponding to lower carboxylic acids by reacting allyl compounds with molecular oxygen in lower carboxylic acids.

Conventionally, manufacturing glycerin esters from petrochemical raw materials requires many complicated steps, and part of the manufacturing process also involves epoxidation using hydrogen peroxide or peracetic acid, which are expensive and difficult to handle. The disadvantage was that a chemical was used. The present inventors have developed various methods for the purpose of providing a novel method for producing glycerin esters with a short process, which does not use epoxidizing agents such as peracids, which are expensive and difficult to handle, and does not require complicated processes. As a result of research, it was found that when a compound having an allyl group, for example allyl acetate, is used as a starting material and is reacted with molecular oxygen in a lower carboxylic acid in the presence of a catalyst such as copper oxide or copper acetate and a halogen molecule or a halogen compound, glycerin They discovered that esters can be obtained and completed the present invention.

That is, the method of the present invention involves molecularly converting an allyl compound into a lower carboxylic acid in the presence of copper oxide or copper acetate and a halogen molecule or halogen compound without using an epoxidizing agent such as peracetic acid or hydrogen peroxide. Glycerin esters are produced directly by reacting with oxygen in one step.

According to the method of the present invention, glycerin esters, which have conventionally been produced from glycerin, can be produced directly from allyl compounds in one step of reaction. Furthermore, since the glycerin esters produced by the method of the present invention are precursors that can be hydrolyzed to produce glycerin with a simple operation, this production process is extremely useful as a method for producing glycerin. Glycerin esters obtained by the method of the present invention are useful compounds that have a wide range of applications such as solvents, plasticizers for synthetic resins, and synthetic intermediates, and are also used as precursors for glycerin production.

The method of the invention carries out the reaction in a lower carboxylic acid, the lower carboxylic acid used acting as a solvent and a reactant.

The lower carboxylic acid has the general formula R2COOH (wherein R2
represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms), and is a carboxylic acid represented by formic acid, acetic acid,
Although propionic acid and the like are used, acetic acid is usually used frequently.

The raw material used in the method of the present invention is a compound having an allyl group, and has the general formula: CH2=CH-CH2-R1
(In the formula, R1 represents -0C0CH3, -0H or a halogen atom).

Typically, compounds such as allyl acetate, allyl alcohol or allyl chloride are used. The glycerin esters obtained by the method of the present invention are more than C.

and/or (wherein R1 is -0C0CH3, -0
R2 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms.

Usually, a mixture of three types of compounds represented by the above general formula is obtained. The amount of the compound represented by XOOO produced is small, and most of it is the compounds represented by the remaining two types of general formulas. These glycerin esters can be hydrolyzed into glycerin by simple operations.

The method of the invention carries out the reaction in the presence of copper oxide or copper acetate and a halogen molecule or compound.

The oxide may be one prepared by thermally decomposing a compound such as a carbonate, hydroxide, or carboxylate, or a commercially available reagent may be used as is. As a halogen molecule,
CI2, Br2 or 12 is used, and as the halogen compound, hydrogen halides such as HCl, HBr, HI, or alkyl halides such as ethyl iodide, ethyl bromide, etc. are used. In the method of the present invention, the amount of copper oxide or copper acetate used is 1 x 10-5rr101/' to 5 m101/' with respect to the carboxylic acid solvent used.
Preferably from 1 x 10-4 m01/' to 5 x 10-
1 m01/', and the amount of the halogen molecule or halogen compound used at the same time is 1 x 10-4 m01/' to 1 m01/' to the carboxylic acid solvent used.
A range of 01/e is preferred.

In the method of the present invention, the reaction is carried out by dissolving the allyl compound in a lower carboxylic acid solvent, and the ratio of the allyl compound to the lower carboxylic acid is usually 0.05 to 10% by weight.
, preferably in the range of 1 to 50% by weight.

The molecular oxygen used in the method of the invention is usually oxygen gas or air.

The method of the invention preferably comprises
The reaction temperature ranges from 110 to 180°C and the reaction pressure required to maintain the reaction solution (carboxylic acid in which the allyl compound is dissolved) within this reaction temperature range is usually 2 to 100k9/C! i
Implemented within the scope of.

The pressure of molecular oxygen (oxygen or air) is 2 to 1 above.
00kg/c! A range of 1i is used. The method of the present invention is actually carried out in a pressurized vessel equipped with a stirrer, but the reaction format may be either batchwise or continuous.

Examples of the method of the present invention are shown below.

Example 1 In a Hastelloy autoclave with an internal volume of 50 cc, 0.1 f1 of copper oxide, 0.5 y of hydrogen chloride (HCl), and 6 ml of acetic acid were added.
, and 2.5f of allyl acetate, and 50k9 of air.
/C7lf (room temperature) was press-fitted.

The autoclave was heated from the outside with an oil bath, the reaction temperature was maintained at 150C, and the reaction was carried out with stirring for 5 hours. After the reaction, the autoclave was cooled, and the reaction solution was quantified by gas chromatography. The yield of glycerin diacetate was 0.65', the yield of glycerin monoacetate was 0.48y, and the conversion rate of allyl acetate was 45.
．． It was 5 mol%. Example 2 A similar reaction was carried out using the same reaction apparatus and reaction method as in Example 1, using copper acetate instead of copper oxide, and using iodine (12) instead of hydrogen chloride.

When the reaction solution was similarly quantified, the yield of glycerin diacetate was 0.86y, the yield of glycerin triacetate was 0.65y, and the conversion rate of allyl acetate was 152.1y.
It was mol%.

Examples 3 to 7 Raw materials used in the same reaction apparatus and reaction method as in Example 1,
Reactions were carried out using various catalysts.

Claims (1)

[Claims] 1 An allyl compound represented by the general formula CH_2=CH-CH_2R_1 (in the formula, R_1 represents -OCOCH_3, -OH or a halogen atom) is an allyl compound represented by the general formula R_2COOH (in the formula, R_2 is hydrogen Atom, or 1 to 5 carbon atoms
Glycerin esters characterized by reacting with molecular oxygen in a lower carboxylic acid represented by (representing an alkyl group) in the presence of copper oxide or copper acetate, and a halogen molecule, hydrogen halide, or alkyl halide. manufacturing method.