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.

Vilsmair salts have been used to prepare a series of thioaldehyde molecules conjugated with a pyrrole ring (pyrrole substituents:  H, Me, Et). The reaction of 3,5-dimethyl-4-ethylpyrrole-2-carbothioaldehyde (HL4) with [RuHCl(CO)(PPh3)3] or [RuHCl(CO)(BTD)(PPh3)2] (BTD = 2,1,3-benzothiadiazole) in the presence of NaOMe leads to the complex [RuH(κ2-L4)(CO)(PPh3)2], in which the carbothioaldehyde ligand acts as a bidentate, three-electron donor. The same approach yields the aryl, alkenyl, and alkynyl complexes [RuR(κ2-L4)(CO)(PPh3)2] (R = C6H5, CHCH2, CHCHPh, CHCHC6H4Me-4, CHCHtBu, CHCHCPh2OH, CHCH(HO)C6H10, C(C⋮CPh)CHPh, C⋮CPh). The compound [Ru(CHCHCPh2OH)(κ2-L4)(CO)(PPh3)2] can be dehydrated by reaction with HBF4 to yield the vinylcarbene species [Ru(CHCHCPh2)(κ2-L4)(CO)(PPh3)2]BF4. The complexes [RuR(κ2-L6)(CO)(PPh3)2] (R = H, CHCH2, CHCHC6H4Me-4, C(C⋮CPh)CHPh) were prepared from pyrrole-2-carboxaldehyde (HL6), the oxygen analogue of the carbothioaldehyde ligands. Additionally, the osmium ethenyl compounds [Os(CHCH2)(κ2-L4)(CO)(PPh3)2] and [Os(CHCH2)(κ2-L6)(CO)(PPh3)2] were synthesized from [Os(CHCH2)Cl(CO)(BTD)(PPh3)2] with either HL4 or HL6 in the presence of NaOMe. The crystal structures of the principal ligand and three representative complexes are reported.

No abstract