The dichlorodihydridoruthenium (IV) compound [RuH 2 Cl 2 -were obtained. The phenylvinylidene complex [RuCl 2 (=C= CHPh)(PCy 3 ) 2 ] (15) was prepared from phenylacetylene and (PiPr 3 ) 2 ] (4) was prepared from [RuCl 2 (C 8 H 12 )] n (3), PiPr 3 , and H 2 in 2-butanol via the chlorohydridoruthenium(II) derivative either [RuH 2 Cl 2 (PCy 3 ) 2 ] (14) or one of the carbene derivatives [RuCl 2 (=CHR)(PCy 3 ) 2 ] (16, 17) as starting materials. The [RuHCl(H 2 )(PiPr 3 ) 2 ] ( 5) as an intermediate. The synthesis of 5 was achieved under similar conditions from 3, PiPr 3 , H 2 , X-ray crystal structure analysis of 15 confirms a distorted square-pyramidal geometry with the vinylidene ligand in the and 2-butanol in the presence of NEt 3 . Compound 4, which was characterized by X-ray crystal structure analysis, reacts apical position. The interconversion of 4 to 5 and of the tricyclohexylphosphane counterparts 14 to 13 was achieved with excess phenylacetylene to give the phenylvinylidene complex [RuCl 2 (=C=CHPh)(PiPr 3 ) 2 ] (7) and with propargylic by hydrogen transfer from 2-propanol in the presence of PR 3 .
The reverse reaction occurs upon treatment of 5 or 13 with alcohols or derivatives thereof to afford the vinylcarbene complexes [RuCl 2 (=CHCH=CR 2 )(PiPr 3 ) 2 ] (9, 10), respectively.
the corresponding phosphonium salt [HPR 3 ]Cl or HCl, respectively. From 5 and terminal alkynes RCϵCH the chlorohydridovinylidene compounds [RuHCl(=C=CHR)(PiPr 3 ) 2 ] (11, 12) [᭛] Part 46: H.