title: A simple and general chiral silicon Lewis acid for asymmetric synthesis: highly enantioselective [3+2] acylhydrazone-enol ether cycloadditions.
abstract: A highly diastereo- and enantioselective [3 + 2] acylhydrazone-enol ether cycloaddition mediated by a simple chiral silane Lewis acid is described. The reactions are highly practical, as demonstrated by a larger scale (5 g of the hydrazone) reaction in which the product was obtained after recrystallization in 93% yield and 99% ee. Evidence for a stepwise mechanism and a model for the asymmetric induction are presented, as well.
authors: Department of Chemistry, Columbia University, New York, New York 10027, USA.
authors: Seiji
authors: S
authors: Shirakawa
authors: Pamela J
authors: PJ
authors: Lombardi
authors: James L
authors: JL
authors: Leighton