Lewis Base Catalyzed Aldol Additions of Chiral Trichlorosilyl Enolates and Silyl Enol Ethers
作者:Scott E. Denmark、Shinji Fujimori、Son M. Pham
DOI:10.1021/jo051930+
日期:2005.12.1
diastereodifferentiation in chiral Lewis base catalyzed aldoladditions using chiral enoxysilanes derived from lactate, 3-hydroxyisobutyrate, and 3-hydroxybutyrate have been investigated. Trichlorosilylenolates derived from the chiral methyl and ethyl ketones were subjected to aldolization in the presence of phosphoramides, and the intrinsic selectivity of these enolates and the external stereoinduction
Diastereoselective Aldol Addition Reactions of a Chiral Methyl Ketone Trichlorosilyl Enolate under Lewis Base Catalysis
作者:Scott E. Denmark、Shinji Fujimori
DOI:10.1055/s-2001-14652
日期:——
The trichlorosilylenolate of a chiral methyl ketone bearing an oxygen substituent (OTBS) on the β-position undergoes highly diastereoselective aldoladdition to a variety of achiral aldehydes in good yield. The stereochemical course of the reaction is primarily controlled by the configuration of the chiral phosphoramide which serves as an effective catalyst for this transformation.