DE2521500A1 - TRIESTER OF CARBONIC ACIDS AND THE PROCESS FOR THEIR PRODUCTION - Google Patents

Description

" Triesters of carboxylic acids and process for their preparation ;"

The invention relates to Trieste of the general !Formula:

OCOE

OCOR

-C-

R,

OCOR

wherein R stands for an alkyl, arylalkyl, aryl or cycloalkyl radical, while R _x ., R ^, R ^, which can be identical or different, each represent an alkyl, arylalkyl, aryl or cycloalkyl radical or a hydrogen atom , and to a process for making these compounds. The compounds according to the invention are valuable intermediates in organic syntheses, for example in the preparation of oc-hydroxyaldehydes or

509847/1177

ketones, oC acyloxy (or aroyloxy) aldehydes or ketones and clay β-hydroxy amino acids.

The method according to the invention is carried out by that one has a (/ -Halogeneρoxid of the formula:

where R ₁ , Rp and R ~ have the above meaning and Y represents a halogen atom, in the presence of a Lewis acid with the anhydride of an acid RGOOH, where R has the above meaning, and, preferably in a second stage, with an alkali or alkaline earth salt of the acid RCOOH.

The reaction between the haloepoxide and the acid anhydride is carried out at temperatures between -30 and +70 ⁰ C, with the pressure being so selected, that the reaction mixture remains liquid. If necessary, one works in a suitable aromatic solvent, preferably an aromatic nitro or halogen compound, and the further reaction with the salt ... is carried out at temperatures between +25 and unchanged conditions.

is used at temperatures between +25 and +180 ⁰ C below otherwise

Further details are given in the following, non-limiting Meaningful example.

example 1

Production of 1,1,2-triacetoxyethane from monochlorethylene oxide

To 5.27 g (67.2 mmol) of monochlorethylene oxide were 4-0 ml

- 3 ■ -509847 / 1177

Acetic anhydride and 0.22 g anhydrous ferric chloride added. The mixture was stirred for 1 hour at room temperature under a nitrogen atmosphere, whereupon it received 551 g (67.2 mmol) anhydrous sodium acetate was added. and it, still under nitrogen, stirred for a further 60 hours at room temperature and then under for another 48 hours Was held at reflux.

The reaction mixture was at room temperature with 100 ml Diluted methylene chloride and filtered off the precipitated salts. The precipitate was washed with methylene chloride washed out and the combined filtrates dried under vacuum. After taking up with methylene chloride was the residue treated with activated charcoal, the activated charcoal washed out with a little solvent, the solvent Stripped from the combined filtrates in vacuo and the residue purified by distillation.

The 1,1,2-Triacetoxyäthan proceeds at 112 to 114 ° C under 2 mm Hg pressure (bath 150 ⁰ C). A total of 6.86 g of the pure product in the chromatography test with a melting point of 48 ° to 50 ° C. were obtained; Yield 50%.

PATENT CLAIMS:

7/1177

Claims (1)

OGOR
\
G
/
OGOR wherein R represents an alkyl, alkylaryl, aryl or cyeloalkyl radical, while R ^, Rp, R ₃ ,, which can be the same or different, each represent an alkyl, arylalkyl, aryl or cycloalkyl radical or a hydrogen atom. (2) Process for the production of the triesters according to claim 1, characterized in that that one oc-halogen epoxide of the general formula: R. wherein and R, have the above meaning and represents a halogen atom, in the presence of a Lewis acid with the anhydride of an acid RCOOH, in which R has the above meaning, and reacts with an alkali or alkaline earth salt of such an acid. 509847/1 177 (5) Process according to claim 2 or 3 _5, characterized in that the reaction is carried out in two stages, the a-haloepoxide with the acid anhydride in the first stage and the product thus obtained in the second stage with an alkali or alkaline earth metal sal ζ the acid ROOOH converts. (4) Method according to claim 2 or 5? characterized in that in the first stage "works at a temperature between -50 and +? 0 ° G. (5) The method according to any one of claims 2 to 4 ·, characterized in that it is carried in the second stage at temperatures between +25 and +180 ⁰ G. (6) Method according to one of claims 2 to 5 » characterized in that the reaction is carried out in the presence of an aromatic compound, in particular an aromatic nitro or halogen compound. (7) The method according to any one of claims 2 to 6, characterized in that the Carrying out the reaction at a pressure which ensures that the reaction mixture remains liquid. 86HIV 509847 / Ί 1 77