Reactivity of Ru(H)(H₂)Cl(PCy₃)₂ with Propargyl and Vinyl Chlorides:  New Methodology To Give Metathesis-Active Ruthenium Carbenes

Abstract

A procedure for generating the ruthenium hydride complex Ru(H)(H2)Cl(PCy3)2 in 95% yield is presented. Following a novel insertion−elimination pathway, this hydride can react with propargyl or vinyl halides to make metathesis-active vinyl and alkyl carbene species with the general formulas (PCy3)2Cl2RuCH−CHCR2 and (PCy3)2Cl2RuCHR, respectively. Tertiary propargyl chlorides work best, giving Ru−vinyl carbenes in extremely high yield.

The First Grubbs-Type Metathesis Catalyst withcis Stereochemistry: Synthesis of [(η2-dtbpm)Cl2Ru=CH−CH=CMe2] from a Novel, Coordinatively Unsaturated Dinuclear Ruthenium Dihydride

“…[4] Hence, an analogous route starting from appropriate hydrido complexes with diphosphanylmethane ligands seemed attractive.…”

“…We therefore hoped that propargyl or vinyl chlorides [4] would be appropriate substrates for 8. At À 70 8C in toluene, 8 reacted smoothly with 3-chloro-3-methyl-1-butyne, and the green vinylcarbene complex [(h 2 -dtbpm)Cl 2 RuCHÀCHCMe 2 ] (2) was isolated in 62 % yield (Scheme 3).…”

“…[2] The accessibility of Grubbs- ] has been continuously improved, and the range of possible carbene ligand precursors extended from cyclopropenes [1] to diazoalkanes, [3] vinyl and propargyl chlorides, [4] 1,1-dihaloalkanes, [5] and finally to 1-alkynes. [6] Recently, ruthenium carbene complexes with bidentate Schiff base [7] and Wanzlick ± Arduengo-type carbene ligands, [8] as well as Ru vinylidene systems with Cp, hydridotris(pyrazolyl)borate, Cp*, [9] and h 6 -arene [10] ligands have extended the range of ruthenium-based metathesis catalysts.…”

A New Class of Ruthenium Carbene Complexes: Synthesis and Structures of Highly Efficient Catalysts for Olefin Metathesis

“…[14] The dinuclear dihydride 3, accessible in a onepot reaction from [(cod)RuCl 2 ] x (cod 1,5-cyclooctadiene), has been shown to be an excellent precursor for 2 a (Scheme 1), [12] and the cyclohexylidene derivative 2 b can be Scheme 1. Synthesis of complexes 2 a ± d from 3 and propargyl, allenyl, and vinyl chlorides.…”

Alkenylcarbyne Complexes Derived from the Reactions of OsXCl-(PPh3)3(X=H,Cl) with Propargyl Chloride and Phosphine Ligand-Controlled Transformation of Hydride-Carbyne to Carbene

“…对于富电子金属中心的配合物, 2 [4a,12,16] , 而钌的类似反应则是生成其还原异构体 卡宾配合物 RuCl 2 (＝CHR)(PR' 3 ) 2 [16,17] . 正因如此, 报道 的锇-氢卡拜 OsHCl 2 (≡CR)(PR' 3 ) 2 [4a,b,5f,12,13c,16,17c,18,19] 和 钌卡宾 RuCl 2 (＝CHR)(PR' 3 ) 2 [17,20] [22] . Hofmann [23] 和 Fogg 小组 [24] 随后也各自分别报道 …”