Iron-catalyzed Michael reactions revisited: a synthetically useful process for the preparation of tri-carbonyl compounds and chiral warfarin

HM Yang, YH Gao, L Li, ZY Jiang, GQ Lai, CG Xia…

Index: Yang, Hua-Meng; Gao, Yue-Hua; Li, Li; Jiang, Zhen-Yu; Lai, Guo-Qiao; Xia, Chun-Gu; Xu, Li-Wen Tetrahedron Letters, 2010 , vol. 51, # 29 p. 3836 - 3839

Full Text: HTML

Citation Number: 23

Abstract

The LBAs (Lewis acid-assisted Brønsted acid catalysis) is proposed as possible mechanistic process in the simple FeCl3-catalyzed Michael reactions of chalcones with active methylene compounds in organic solvents. And iron salts were found to be effective promoters in the asymmetric Michael addition of 4-hydroxycoumarin to α, β-unsaturated ketone, which resulted in excellent yield and high level of enantioselectivity (up to 91% ee) in the ...