Acetic Acid → HCID 53921987, compound

Participants

Reaction Steps

42 g of 4-chloroacetoacetic acid ethyl ester, 50 g of 2,4,5-trimethoxybenzaldehyde, 2.5 ml of glacial acetic acid and 1 ml of piperidine were dissolved in 60 ml of benzene and the solution was boiled for two hours using a water separator. Although conversion was not yet complete, the mixture was worked up. It was diluted with 200 ml of ethyl acetate, extracted in each case three times with saturated sodium bicarbonate solution, water, 1 M citric acid solution and again with water, dried and evaporated. On fractional crystallization of the residue from methanol, first 20 g of pure product, as the E/Z mixture, and then 10.5 g of unreacted aldehyde could be crystallized. In addition to a large amount of product, the mother liquor still contained only a little aldehyde and, after preliminary purification by chromatography on silica gel, could likewise be crystallized. A further 25 g of product were obtained.

Provenance & Evidence