Sigma-organyl complexes of ruthenium and osmium supported by a mixed-donor ligand

A series of vinyl, aryl, acetylide and silyl complexes Ru(R)(kappa2-MI)(CO)(PPh3)2] (R = CH=CH2, CH=CHPh, CH=CHC6H4CH3-4, CH=CH(t)Bu, CH=2OH, C(C triple bond CPh)=CHPh, C6H5, C triple bond CPh, SiMe2OEt; MI = 1-methylimidazole-2-thiolate) were prepared from either Ru(R)Cl(CO)(PPh3)2] or Ru(R)Cl(CO)(BTD)(PPh3)2](BTD = 2,1,3-benzothiadiazole) by reaction with the nitrogen-sulfur mixed-donor ligand, 1-methyl-2-mercaptoimidazole (HMI), in the presence of base. In the same manner, Os(CH=CHPh)(kappa2-MI)(CO)(PPh3)2] was prepared from Os(CH=CHPh)(CO)Cl(BTD)(PPh3)2]. The in situ hydroruthenation of 1-ethynylcyclohexan-1-ol by RuH(CO)Cl(BTD)(PPh3)2] and subsequent addition of the HMI ligand and excess sodium methoxide yielded the dehydrated 1,3-dienyl complex Ru(CH=CHC6H9)(kappa2-MI)(CO)(PPh3)2]. Dehydration of the complex Ru(CH=CHCPh2OH)(kappa2-MI)(CO)(PPh3)2] with HBF4 yielded the vinyl carbene Ru(=CHCH=CPh2)(kappa2-MI)(CO)(PPh3)2]BF4. The hydride complexes MH(kappa2-MI)(CO)(PPh3)2](M = Ru, Os) were obtained from the reaction of HMI and KOH with RuHCl(CO)(PPh3)3] and OsHCl(CO)(BTD)(PPh3)2], respectively. Reaction of Ru(CH=CHC6H4CH3-4)(kappa2-MI)(CO)(PPh3)2] with excess HC triple bond CPh leads to isolation of the acetylide complex Ru(C triple bond CPh)(kappa2-MI)(CO)(PPh3)2], which is also accessible by direct reaction of Ru(C triple bond CPh)Cl(CO)(BTD)(PPh3)2] with 1-methyl-2-mercaptoimidazole and NaOMe. The thiocarbonyl complex Ru(CPh = CHPh)Cl(CS)(PPh3)2] reacted with HMI and NaOMe without migration to yield Ru(CPh= CHPh)(kappa2-MI)(CS)(PPh3)2], while treatment of Ru(CH=CHPh)Cl(CO)2(PPh3)2] with HMI yielded the monodentate acyl product Ru{eta(1)-C(=O)CH=CHPh}(kappa2-MI)(CO)(PPh3)2]. The single-crystal X-ray structures of five complexes bearing vinyl, aryl, acetylide and dienyl functionality are reported.