GB613834A - Improvements in and relating to the manufacture of vinyl esters or ethers and their homologues - Google Patents

Abstract

Vinyl esters and ethers are produced by reaction of acetylene or its homologues with carboxylic acids or alcohols using mercury compounds and boron fluoride as catalyst, one or more vinyl compounds, in quantities of about 3 per cent or less on the total reactants, being added to the reaction mixture or a component thereof before reaction begins. Reaction product may be separated and added with the two catalysts to fresh reactants. The boron fluoride may be used as a complex with acids, alcohols or ethers or mixtures of boric acid or oxide and hydrofluoric acid may be employed. The addition of hydrofluoric acid to the catalysts increases their activity. The acids reacted with the acetylene may be mono- or polycarboxylic and the alcohols mono- or polyhydric. Acid esters may also be used. In examples: (1) mercuric oxide is dissolved in anhydrous acetic acid, and boron fluoride, hydrogen fluoride and vinyl acetate added. Acetylene is introduced at 15-20 DEG C. and the solution neutralized and distilled to recover vinyl acetate; (2) acetylene is introduced into a mixture of acetic acid, acetic anhydride, mercuric oxide, boric acid, hydrofluoric acid and vinyl butyrate; (3) a mixture of butyric acid with acetic anhydride, mercuric oxide, boron fluoride-acetic acid and vinyl butyrate is treated with acetylene to yield vinyl butyrate; (4) lauric acid mixed with acetic anhydride, hydrogen fluoride, boron fluoride-acetic acid, mercuric oxide and vinyl acetate is treated with acetylene at 40 DEG C., giving vinyl laurate; (5) oxalic acid monoethyl ester is similarly converted to the vinyl derivative; (6) mercuric oxide is dissolved in a mixture of methanol, boron fluoride-ether and vinyl acetate, and a mixture of methanol and butylacetylene added, methyl a -butyl vinyl ether being recovered.