Patent ID: 7405328

Claim:
A method for preparing an alkenone, corresponding to Formula (I): R 1 —C(O)—C(H)═C(H)—OR 2 (I) in which R 1 represents CF 3 , and R 2 represents aryl, substituted aryl, a C1-C4 alkyl group or a C1-C4 alkyl group, which is substituted by at least one halogen atom; said method comprising reacting a carboxylic acid halide with a vinyl ether in an addition reaction in a first step, and subsequently eliminating hydrogen halide in a second step to form the alkenone, wherein the reaction is carried out in the absence of an acid-capturing agent for the resulting hydrogen halide, and the second step is carried out at a temperature in the range from 30° C. to 90° C. wherein the acid halide corresponds to Formula (II): R 1 —C(O)X (II) in which X represents fluorine, chlorine or bromine, and R 1 has the meaning given above, and the vinyl ether corresponds to Formula (III): CH 2 ═C(H)—OR 2 (III) in which R 2 has the meaning given above.