A General Organocatalyst for Direct α-Functionalization of Aldehydes: Stereoselective C−C, C−N, C−F, C−Br, and C−S Bond-Forming Reactions. Scope and Mechanistic Insights
journal contributionposted on 2005-12-28, 00:00 authored by Johan Franzén, Mauro Marigo, Doris Fielenbach, Tobias C. Wabnitz, Anne Kjærsgaard, Karl Anker Jørgensen
The development of a general organocatalyst for the α-functionalization of aldehydes, via an enamine intermediate, is presented. Based on optically active α,α-diarylprolinol silyl ethers, the scope and applications of this catalyst for the stereogenic formation of C−C, C−N, C−F, C−Br, and C−S bonds are outlined. The reactions all proceed in good to high yields and with excellent enantioselectivities. Furthermore, we will present mechanistic insight into the reaction course applying nonlinear effect studies, kinetic resolution, and computational investigations leading to an understanding of the properties of the α,α-diarylprolinol silyl ether catalysts.
enamineDirect α- Functionalizationinsightstereogenic formationAldehydeScopenonlinear effect studiesapplicationdiarylprolinoletherinvestigationGeneral Organocatalystaldehydescopeenantioselectivitiereaction coursesilylunderstandingBond-FormingMechanistic InsightsStereoselectiveyieldα- functionalizationorganocatalystbond