MOLECULAR RECOGNITION BY ARTIFICIAL CHIRAL CATALYSTS UTILIZING A METAL CHELATE - A REMARKABLE DIFFERENCE IN REACTIVITY BETWEEN GEOMETRICAL ISOMERS OF SILYL ENOLATES IN ASYMMETRIC ALDOL REACTIONS USING CHIRAL TIN(II) CATALYSTS

摘要

A remarkable difference in reactivity between (E)- and (Z)-enolates in the asymmetric aldol reactions of silyl enolates with aldehydes using chiral tin(II) Lewis acids was found. This difference can be interpreted to mean that the chiral catalyst coordinated by aldehydes via a metal chelate recognizes the geometry of the silyl enolates. [References: 21]