| abstract |
3-Acylazo-propionic acid esters of the general formula I <IMAGE> and isomers thereof (in which R1 represents C1-C6-alkyl and R2 represents alkoxy or amino), suitable as starting materials for the manufacture of 1,2,3-thiadiazole-5- carboxylic acid derivatives, are prepared by a process which comprises reacting an acrylic acid ester of the general formula H2C=CH-COOR1 with a hydrazine derivative of the general formula H2N-NH-CO-R2 to form a 3- acylhydrazino-propionic acid ester of the general formula <IMAGE> and oxidizing this ester in an inert solvent with an oxidizing agent.n[GB2081265A] |