Piperonal → HCID 23050471, compound

Participants

Reaction Steps

A solution of 5 ml (60 mmol) of methyl propiolate in 60 ml of tetrahydrofuran was treated at -78° under argon with 37.5 ml of n-butyllithium (1.6M in hexane). The mixture was stirred at -78° for 10 minutes and then a solution of 9 g 60 mmol) of 3,4 -methylenedioxybenzaldehyde in 60 ml of tetrahydrofuran was added within 30 minutes. The reaction mixture was stirred at -78° for a further 20 minutes, then brought to room temperature and treated with 80 ml of saturated ammonium chloride solution. The aqueous phase was extracted twice with ether. The combined organic phases were washed in succession with saturated sodium chloride solution and with water, dried over sodium sulphate and concentrated. The residue was purified by flash chromatography on 500 g of silica gel (elution agent methylene chloride/ethyl acetate 9:1). There was obtained methyl 4-hydroxy-4-[3,4-(methylenedioxy) phenyl]-2-butynoate as a brown oil.

Provenance & Evidence