A catalytic enantioselective synthetic strategy for the aryl-substituted all-carbon quaternary stereocenters of bioactive hydrodibenzofuran alkaloids was achieved by the Michael addition reaction of α-cyano ketones and acrylates using a chiral tertiary amine–thiourea catalyst. This method can tolerate steric bulkiness and multiple functional groups, and 32 Michael adducts were prepared in good to excellent
Asymmetric Synthesis of Bioactive Hydrodibenzofuran Alkaloids: (−)-Lycoramine, (−)-Galanthamine, and (+)-Lunarine
作者:Peng Chen、Xu Bao、Le-Fen Zhang、Ming Ding、Xiao-Jie Han、Jing Li、Guo-Biao Zhang、Yong-Qiang Tu、Chun-An Fan
DOI:10.1002/anie.201103198
日期:2011.8.22
Divergent route: A direct CC bond‐forming approach to the key aryl‐substituted all‐carbon quaternary stereogenic center present in bioactive hydrodibenzofuran alkaloids has been discovered. This approach involves an unprecedented organocatalyticenantioselectiveMichaeladdition of α‐cyanoketones with acrylates (see scheme) and was used in a novel and divergent synthetic strategy for the title compounds