Organocatalytic Iminium Ion/Carbene Reaction Cascade for the Formation of Optically Active 2,4-Disubstituted Cyclopentenones
作者:Christian Borch Jacobsen、Kim L. Jensen、Jonas Udmark、Karl Anker Jørgensen
DOI:10.1021/ol2018104
日期:2011.9.16
An organocatalytic iminium ion/N-heterocyclic carbene (NHC) cascade reaction between β-keto phenyltetrazolesulfones and α,β-unsaturated aldehydes, providing direct access to opticallyactive 2,4-disubstituted cyclopent-2-enones, has been developed. The products are isolated in good yields with high enantioselectivities.
Asymmetric Organocatalytic Formal Alkynylation and Alkenylation of α,β-Unsaturated Aldehydes
作者:Martin Nielsen、Christian Borch Jacobsen、Márcio W. Paixão、Nicole Holub、Karl Anker Jørgensen
DOI:10.1021/ja903920j
日期:2009.8.5
stereoselective organocatalytic one-pot protocol for the formal alkynylation and alkenylation of alpha,beta-unsaturated aldehydes using novel chemistry based on beta-keto heterocyclic sulfones is presented. The organocatalytic step is catalyzed by a prolinol derivative and allows for the formation of important optically active compounds. Further transformations of the beta-keto heterocyclic sulfone moiety,