P(NMe<sub>2</sub>)<sub>3</sub>-Mediated Umpolung Alkylation and Nonylidic Olefination of α-Keto Esters
作者:Sunewang Rixin Wang、Alexander T. Radosevich
DOI:10.1021/acs.orglett.5b01784
日期:2015.8.7
A commercial phosphorus-based reagent (P(NMe2)(3)) mediates,umpolung alkylation of methyl aroylformates with benzylic and allylic bromides, leading to either Barer-type addition or ylide-free olefination products upon workup. The reaction sequence is initiated, by a two-electron redox addition of the tricoordinate phosphorus reagent with an alpha-keto ester Compound (Kukhtin-Ramirez addition). A mechanistic rationale is offered for the chemoselectivity upon which the success of this nonmetal mediated C-C bond forming strategy is based.