Synthesis of the key intermediate of ramelteon

allylcopper 试剂的不对称的结合的增加源于 allyl Grignard 试剂和 CuBr 敮 ???

Asymmetric conjugated addition of allylcopper reagents derived from an allyl Grignard reagent and CuBr·Me_2S to chiralα,β-unsaturated N-acyl oxazolidinones has been achieved.The synthetic procedure was applied to the preparation of the key intermediate of the novel nonbenzodiazepine hypnotic drug,ramelteon.