Derailing the Wacker Oxidation: Development of a Palladium-Catalyzed Amidation Reaction
作者:Matthew J. Gaunt、Jonathan B. Spencer
DOI:10.1021/ol0066882
日期:2001.1.1
[figure: see text] A conceptuallynew palladium-catalyzed amidation reaction is described for the synthesis of beta-amido ketones based on derailing the Wacker oxidation of enones. This reaction generates a new carbon-nitrogen bond via a palladium-catalyzed conjugate addition of a carbamate nucleophile to an enone. The regiocontrol, mild and neutral conditions, lack of preactivation of the nucleophile
Evidence That Protons Can Be the Active Catalysts in Lewis Acid Mediated Hetero-Michael Addition Reactions
作者:Tobias C. Wabnitz、Jin-Quan Yu、Jonathan B. Spencer
DOI:10.1002/chem.200305407
日期:2004.1.23
mechanism of Lewis acid catalysed hetero-Michael addition reactions of weakly basic nucleophiles to alpha,beta-unsaturated ketones was investigated. Protons, rather than metal ions, were identified as the active catalysts. Other mechanisms have been ruled out by analyses of side products and of stoichiometric enone-catalyst mixtures and by the use of radical inhibitors. No evidence for the involvement
Convenient synthesis of Cbz-protected β-amino ketones by a copper-catalysed conjugate addition reaction
作者:Tobias C Wabnitz、Jonathan B Spencer
DOI:10.1016/s0040-4039(02)00654-8
日期:2002.5
A convenient synthesis of Cbz-protected β-amino ketones is reported. Benzyl carbamates and α,β-unsaturated ketones furnish the conjugateaddition products in the presence of a Cu(II) catalyst under mild conditions. Other weakly basic nitrogen nucleophiles can also be used in this reaction.
A General, Polymer-SupportedAcid Catalyzed Hetero-Michael Addition
作者:Jonathan B. Spencer、Tobias C. Wabnitz、Jin-Quan Yu
DOI:10.1055/s-2003-39292
日期:——
Hetero-Michael additions of nitrogen, oxygen and sulfur nucleophiles to α,β-unsaturated ketones were efficiently catalyzed by Nafion® SAC-13 perfluorinated resinsulfonic acid.
Reaction of Allylzinc Reagents and Zinc Enolates of Ketones with α-Amidoalkylphenyl Sulfones
作者:Marino Petrini、Roberto Profeta、Paolo Righi
DOI:10.1021/jo025606f
日期:2002.6.1
Alpha-amidoalkylphenyl sulfones behave as N-acylimino equivalents in the reaction with functionalized allylzinc reagents. The addition products obtained using the zinc derivative of ethyl 2-(bromomethyl)acrylate can be readily transformed into alpha-methylene-gamma-lactams using different cyclization procedures. The allylzinc reagent obtained from 3-bromo-1-acetoxy-1-propene directly affords protected