Anti-Markovnikov Hydroalkylation of Allylic Amine Derivatives via a Palladium-Catalyzed Reductive Cross-Coupling Reaction
作者:Ryan J. DeLuca、Matthew S. Sigman
DOI:10.1021/ja204080s
日期:2011.8.3
Palladium-catalyzed hydroalkylation of allylic amine derivatives by alkylzinc reagents is reported. This reductive cross-coupling reaction yields anti-Markovnikov products using a variety of allylic amine protecting groups. Preliminary mechanistic studies suggest that a reversible β-hydride elimination/hydride insertion process furnishes the primary Pd-alkyl intermediate, which then undergoes transmetalation
metal-catalyzed carbometallation of unsaturated hydrocarbons constitutes one of the most efficient synthetic methodologies for the construction of C—C bond. Recently, the incorporation of organometallic reagent with the CO gas as a nucleophilic acyl synthon could enable the acylmetallation reaction, which greatly increases the horizon of carbometallation chemistry. Herein, we report a nickel-catalyzed
nickel-catalyzed acylation of vinylpyridines with CO at atmospheric pressure is reported, allowing for an expedient approach to synthesize β-acyl pyridine derivatives with high regio- and chemoselectivity. The electron-withdrawing property of pyridine plays pivotal roles in activating the alkenyl group, thereby facilitating this carbonylative process. In addition to vinylpyridines, other alkenylheterocycles
报道了在大气压下镍催化乙烯基吡啶与 CO 的酰化反应,为合成具有高区域选择性和化学选择性的 β-酰基吡啶衍生物提供了一种简便的方法。吡啶的吸电子特性在激活烯基方面发挥着关键作用,从而促进了这一羰基化过程。除乙烯基吡啶外,其他烯基杂环如噻唑和喹啉也适用于该方法。
Palladium-Catalyzed Hydroalkylation of Styrenes with Organozinc Reagents To Form Carbon−Carbon sp<sup>3</sup>−sp<sup>3</sup> Bonds under Oxidative Conditions
作者:Kaveri Balan Urkalan、Matthew S. Sigman
DOI:10.1021/ja908545b
日期:2009.12.23
An unconventional route for the formation of sp(3)-sp(3) C-C bonds from various styrenes and an organozinc reagent in a formal alkene hydroalkylation process is detailed. Mechanistically, this process is proposed to proceed by initial transmetalation followed by formation of a Pd-H species, which is subsequently trapped by the styrene.