Cleavage of H-C(sp2) and C(sp2)-X bonds (X = alkyl, aryl, OR, NR2):: Facile decarbonylation, isonitrile abstraction, or dehydrogenation of aldehydes, esters, amides, amines, and imines by [RuHCl(PiPr3)2]2

The RuHClL2 fragment (L = (PPr3)-Pr-i) reacts at 25 degrees C with a dozen different G=CHE compounds (G = O, E = R, OR, NR2; G = NR, E = R) to give ct-acid abstraction products, RuHCl(CG)L-2, and E-H. For E-H = C2H5OH, alcohol is decarbonylated in a second step to give an additional CO ligand and CH4. For E-H = HNR(CR'H-2), amine can be dehydrogenated by RuHClL2 to give RuH(H-2)ClL2 and CR'(2)=NR. X-ray crystallographic studies are presented for the DMF decarbonylation intermediate Ru(H)(2)Cl(eta(2)-C(O)NMe2)L-2, where the strong reducing potential of RuHClL2 is manifested in the formally Ru(IV) species obtained from oxidative addition of H-C(O)NMe2. The structure of Ru(H-2)Cl(eta(2)-C6H4CH=NMe)L-2, the product from aryl C-H activation of benzylidenemethylamine, PhHC=NMe, is also presented. This ability to abstract CO, isonitrile, or H-2 is traced to the considerable pi-basicity of RuHCl((PPr3)-Pr-i)(2).