Efficient direct asymmetric vinylogous Michael addition reactions of γ-butenolides to chalcones catalyzed by vicinal primary-diamine salts
作者:Junfeng Wang、Chao Qi、Zemei Ge、Tieming Cheng、Runtao Li
DOI:10.1039/b923925a
日期:——
The first directorganocatalytic asymmetric vinylogousMichaeladdition reactions of gamma-butenolides to chalcones have been developed by using chiral 1,2-diaminocyclohexane as a novel organocatalyst via a di-iminium transition state to provide syn-Michael products with good yields, high diastereoselectivities and enantioselectivities (up to 78% yield, >99 : 1 dr and 96% ee).