Iron-catalysed allylation–hydrogenation sequences as masked alkyl–alkyl cross-couplings
作者:Josef Bernauer、Guojiao Wu、Axel Jacobi von Wangelin
DOI:10.1039/c9ra07604b
日期:——
organomagnesium reagents (alkyl, aryl) with simple allyl acetates proceeds under mild conditions (Fe(OAc)2 or Fe(acac)2, Et2O, r.t.) to furnish various alkene and styrene derivatives. Mechanistic studies indicate the operation of a homotopic catalyst. The sequential combination of such iron-catalysed allylation with an iron-catalysed hydrogenation results in overall C(sp3)–C(sp3)-bond formation that constitutes
在温和条件下(Fe(OAc) 2或 Fe(acac) 2 , Et 2 O, rt),有机镁试剂(烷基、芳基)与简单的乙酸烯丙酯发生铁催化烯丙基化反应,得到各种烯烃和苯乙烯衍生物。机理研究表明了同伦催化剂的运作。这种铁催化烯丙基化与铁催化氢化的顺序组合导致整体C(sp 3 )–C(sp 3 )-键形成,这构成了具有挑战性的与烷基卤化物的直接交叉偶联方案的有吸引力的替代方案。
Ligand Effects on Negishi Couplings of Alkenyl Halides
作者:Arkady Krasovskiy、Bruce H. Lipshutz
DOI:10.1021/ol2010165
日期:2011.8.5
Negishi couplings at olefinic centers do not always occur with the anticipated maintenance of stereochemistry. The source of erosion has been traced to the ligand, and a modified method has been developed that solves the stereochemical issue and significantly improves yields of Negishi couplings in general.
Alkylzirconation of alkynes catalyzed by triphenylcarbenium tetrakis(pentafluorophenyl)borate
[(C6H5)(3)C](+)[B(C6F5)(4)](-) effectively catalyzes the alkylmetallation of alkynes by using the alkylzirconium species, which is generated by the hydrozirconation of alkenes. (C) 1999 Elsevier Science Ltd. All rights reserved.
Cross-Couplings of Alkyl Electrophiles under “Ligandless” Conditions: Negishi Reactions of Organozirconium Reagents
作者:Sheryl L. Wiskur、Alexander Korte、Gregory C. Fu
DOI:10.1021/ja0393729
日期:2004.1.1
This report establishes that simple, "ligandless" palladium complexes can catalyze the first zirconium-Negishi reactions of alkyl electrophiles. In view of the attractiveness of ligandless catalysts (cost, simplicity, and ease of purification), these observations add a significant and intriguing new dimension to the development of effective palladium-based processes for coupling alkyl electrophiles.
Olefin inversion. 1. Reaction of aliphatic epoxides with triphenylphosphine dihalides