Catalytic asymmetric aza Diels-Alder reactions of hydrazones using a chiral zirconium catalyst

摘要

Catalytic asymmetric aza Diels-Alder reactions of acylhydrazones with Danishefsky's dienes have been developed.A chiral zirconium complex derived from zirconium propoxide and 3,3',6,6'-I_4BINOL was found to be effective in this reaction,and the desired optically active 2,3-dihydro-4-pyridone derivatives were obtained with high enantioselectivities.Asymmetric formal synthesis of a natural product,coniine,was conducted using this catalytic asymmetric reaction as a key step.