Summary of main observation and conclusion An enantioselective desymmetric nucleophilic α-addition of cyclohexanone to propiolamide has been developed through a 6-exo-dig cyclization reaction.By employing simple and ...Summary of main observation and conclusion An enantioselective desymmetric nucleophilic α-addition of cyclohexanone to propiolamide has been developed through a 6-exo-dig cyclization reaction.By employing simple and readily available L-proline sodium salt as a bifunctional catalyst,a series of chiral 6,6-bicyclic bridged products bearing morphan scaffold have been isolated in good yields and excellent enantioselectivities.Density functional theory (DFT)calculations elucidated the origins of the enantioselectivity and regioselectivity of this transformation.A salt bridge that links the amide carbonyl group with proline carboxylate in the transition state was proven to be the driving force for the induction of excellent enantioselectivity.展开更多
基金the National Natural Science Foundation of China (Nos.21522207,21702184,and 21772175,YXJ and RXL)the Chinese "Thousand Youth Talents Plan"(XH),and the Chinese "Fundamental Research Funds for the Central Universities" (XH).
文摘Summary of main observation and conclusion An enantioselective desymmetric nucleophilic α-addition of cyclohexanone to propiolamide has been developed through a 6-exo-dig cyclization reaction.By employing simple and readily available L-proline sodium salt as a bifunctional catalyst,a series of chiral 6,6-bicyclic bridged products bearing morphan scaffold have been isolated in good yields and excellent enantioselectivities.Density functional theory (DFT)calculations elucidated the origins of the enantioselectivity and regioselectivity of this transformation.A salt bridge that links the amide carbonyl group with proline carboxylate in the transition state was proven to be the driving force for the induction of excellent enantioselectivity.
