Menthol → 2-(Pyrrol-1-yl)malonic acid ethyl (-)-menthyl ester

Participants

Reaction Conditions

Reaction Steps

To a mixture of 2-(pyrrol-1-yl)malonic acid diethyl ester (300.0 g) and (-)-menthol (417.0 g) was added tetraethyl titanate (10.0 g), and the resulting mixture was stirred at 110° C. for 19 hours. After removal of the (-)-menthol under reduced pressure, the residue was chromatographed on silica gel using n-hexane/ethyl acetate (50:1) as the eluent. Fractions containing the title compound were pooled and evaporated under reduced pressure to give the title compound (142.0 g, 31.8%) as a colorless oil.

Provenance & Evidence