Asymmetric Aldol Condensation of 1-Naphtol and Pyruvates in the Presence of Lewis Acids Preliminary Communication

Lewis acids catalyze teh condensation of methyl pyruvate and l-naphtol to give menthyl 2-hydroxy-2-(l-hydroxy-2-naphtyl)propionate in a ratio of up 96:4 in favor of the levorotatory diastereoisomer. Epimerization, at 25°C for five days, occurs on benzylic carbon atom to give a 30:70 mixture enriched with the dextrorotatory isomer.