Organocatalytic Asymmetric Conjugate Addition of Aldehydes to Nitroolefins : Identification of Catalytic Intermediates and the Stereoselectivity-Determining Step by ESI-MS.
Date Issued
2013-01-01
Author(s)
DOI
10.1002/anie.201305338
Abstract
Looking back: The asymmetric organocatalytic 1,4-addition of aldehydes to nitroolefins was studied by ESI-MS. Analysis of the back reaction starting from quasienantiomeric mass-labeled 1,4-adducts provided conclusive evidence for an enamine rather than an enol mechanism, and allowed identification of the enantioselectivity-determining step.