Cp*Ru(II) and Cp*Ru(IV)-catalyzed reactions of CHX with vinyl C–H bonds: competition between double bond homologation and olefin cyclopropanation by alkyl diazoacetate
摘要:
When diazoesters are used as carbene precursors, new Ru(II) and Ru(IV) complexes bearing various substitutents tethered ligands mediate the formal carbene insertion into C-H vinyl bonds of(substituted) styrenes to yield mostly E- and Z-styrylacetic esters (e.g. 4-phenylbut-3-enoates with styrene). This rarely observed reaction competes with the cyclopropanation of the double bond. The influence of steric and electronic factors on the two competitive reactions is reported. The observation that the most efficient C-H insertion catalysts also promote the ROMP of norbornene lend support to the formation of ruthenacyclobutanes as reaction intermediates. (C) 1998 Elsevier Science S.A. All rights reserved.
Reactions of metalloalkynes. New C2 bonding mode in a trimetallic complexElectronic supplementary information (ESI) available: Synthesis and characterisation of complexes 4a and 4b. See http://www.rsc.org/suppdata/cc/b1/b110930h/This paper constitutes Part 4 of the series.
作者:Christopher S. Griffith、George A. Koutsantonis、Brian W. Skelton、Allan H. White
DOI:10.1039/b110930h
日期:2002.9.11
The reaction of the silver complexes [((Ru(CO)2(eta-C5H4R))2(mu-C identical to C))3Ag3][BF4]3 (R = H or Me) with [RuCl(CO)2(eta-C5H4R)] at room temperature gave the new trimetalliccomplexes [(Ru(CO)2(eta-C5H4R))3(eta 1:eta 2-C identical to C))][BF4] which contain the C2(2-) ligand surrounded by ruthenium atoms; these complexes do not contain metal-metal bonds and were characterised by single crystal