Highly Selective Dehydrogenative Silylation of Alkenes Catalyzed by Rhenium Complexes
作者:Yanfeng Jiang、Olivier Blacque、Thomas Fox、Christian M. Frech、Heinz Berke
DOI:10.1002/chem.200802019
日期:2009.2.16
chemicals: Rhenium(I) complexes of type [ReBr2(L)(NO)(PR3)2] (L=H2 (1), CH3CN (2), ethylene (3); R=iPr (a), cyclohexyl (b)) proved to be suitable catalyst precursors for the highlyselectivedehydrogenativesilylation of alkenes. Two types of rhenium(I) hydride species, [ReBrH(NO)(PR3)2] (4) and [ReBr(η2‐CH2CHR1)H(NO)(PR3)2] (5), were found in the [ReBr2(L)(NO)(PR3)2]‐catalyzeddehydrogenative silylation
选择化学药品:[ReBr 2(L)(NO)(PR 3)2 ]类型的R(I)配合物(L = H 2(1),CH 3 CN(2),乙烯(3); R = i Pr (a),环己基(b))被证明是用于烯烃的高度选择性脱氢甲硅烷基化的合适催化剂前体。两种类型的铼(I)氢化物种,[ReBrH(NO)(PR 3)2 ](4)和[ReBr(η 2 -CH 2 CHR 1)H(NO)(PR 3)2 ](5),是在[ReBr 2(L)(NO)(PR 3)2 ]催化的烯烃脱氢甲硅烷基化反应中发现的。
Base-Mediated Defluorosilylation of C(sp<sup>2</sup>
)−F and C(sp<sup>3</sup>
)−F Bonds
作者:Xiang-Wei Liu、Cayetana Zarate、Ruben Martin
DOI:10.1002/anie.201813294
日期:2019.2.11
The ability to selectively forge C–heteroatom bonds by C−F scission is typically accomplished by metal catalysts, specialized ligands and/or harsh reaction conditions. Described herein is a base‐mediated defluorosilylation of unactivated C(sp2)−F and C(sp3)−Fbonds that obviates the need for metal catalysts. This protocol is characterized by its simplicity, mild reaction conditions, and wide scope
A pyridyl-tethered robust azomethine ylidethermallyrearranges to a chelating cyclic(alkyl)(amino)carbene (CAAC) by the mediacy of CuCl in an intriguing fashion. However, without the CuCl, it cyclizes to a chelating aziridine. Both are bidentate ligands giving cationic Rh(I) complexes that are highly active catalysts for olefin hydrosilylation. The aziridine-based catalyst was surprisingly found to