Two phase preparation of carboxylic acid esters
AssigneeSolvay Fluor und Derivate GmbH
InventorsMax Braun, Kerstin Eichholz, Werner Rudolph
Life of this patent
Estimating the term…
Abstract
The methyl and ethyl esters of trifluoroacetic acid or chlorodifluoroacetic acid can be prepared in a technically simple manner from the corresponding acid chlorides and methanol or ethanol, respectively, in the presence of an “onium” salt of the acid as a catalyst. The alcohol is used in a stoichiometric excess, namely the molar ratio of alcohol to acid chloride is selected such that operation is in the region of a two-phase reaction. One of the phases is formed by the desired ester product, which is obtained in a high purity without any distillation.
Claims8
A method for preparing a methyl or ethyl ester of trifluoroacetic acid or chlorodifluoroacetic acid, comprising:
- reacting an acid chloride of trifluoroacetic acid or chlorodifluoroacetic acid with a stoichiometric excess of methyl or ethalcohol in the presence of an onium salt of the acid as catalyst, wherein the molar ratio of alcohol to acid chloride is selected such that two phases can form;
- allowing an upper phase and a lower phase to form, one phase being an ester phase which contains the ester in a purity, achievable without a distillation stage, of at least 95% by weight;
- and
- separating said ester phase.
Dependencies are inferred from the claim text.