Synergistic Peptide and Gold Catalysis: Enantioselective Addition of Branched Aldehydes to Allenamides
作者:Leo D. M. Nicholls、Helma Wennemers
DOI:10.1002/chem.202103197
日期:2021.12.15
A synergistic combination of a tripeptide and a gold complex catalyzes the enantioselectiveaddition between branchedaldehydes and allenamides to furnish synthetically versatile γ,δ-enamide aldehydes with a fully substituted stereogenic center. Mechanistic studies offered key insights into the role of the peptide and acid/base additives.
Organocatalytic Asymmetric Conjugate Addition of Aldehydes to Nitroolefins: Identification of Catalytic Intermediates and the Stereoselectivity-Determining Step by ESI-MS
Looking back: The asymmetricorganocatalytic 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 (see scheme) provided conclusive evidence for an enamine rather than an enol mechanism, and allowed identification of the enantioselectivity‐determining step.