Piperidine → 3-(3,4-Dimethoxybenzylidene)-2,4-pentanedione

Participants

Reaction Steps

3-(3,4-dimethoxybenzylidene)-2,4-pentanedione (hereinafter “Compound 2”) was prepared by the condensation of 3,4-dimethoxy benzaldehyde with acetyl acetone in the presence of piperidine and cyclohexane as the reaction medium at reflux temperature under continuous azeotropic water removal. The reaction takes about eight hours to complete. The reaction product was purified by crystallization with methanol. The typical yield of Compound 2 is about 67% with a purity, as determined by GC, of about 99.5%. Compound 2 is an off-white free-flowing powder having a melting point of 104-108° C. with a λmax at 335 nm.

Provenance & Evidence