Synlett 2004(13): 2411-2416  
DOI: 10.1055/s-2004-834789
CLUSTER
© Georg Thieme Verlag Stuttgart · New York

Lewis Base Activation of Lewis Acids: Vinylogous Aldol Additions of Silyl Dienol Ethers to Aldehydes

Scott E. Denmark*, Jr. John R. Heemstra
Roger Adams Laboratory, Department of Chemistry, University of Illinois, Urbana, IL 61801, USA
Fax: +1(217)3333984; e-Mail: denmark@scs.uiuc.edu;
Further Information

Publication History

Received 1 July 2004
Publication Date:
07 October 2004 (online)

Abstract

Highly regioselective vinylogous aldol additions of silyl dienol ethers derived from simple α,β-unsaturated ketones are ­described. The catalyst system of silicon tetrachloride activated by chiral bisphosphoramide (R,R)-1 effectively promotes the addition of both γ-substituted and unsubstituted silyl dienol ethers to a ­variety of aldehydes with exclusive γ-regioselectivity and good to excellent diastereo- and enantioselectivity.

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Catalyst (R,R)-1 is commercially available from Obiter Research, LLC, contact waboulanger@obiterresearch.com.