Isocyanide complexes of zerovalent ruthenium. Proton addition to a transition-metal base offering alternative base sites

Ru(CO)2(CNR)(PPh3)2, Ru(CO)(CNR)(PPh3)3, and the dioxygen complex Ru(O2)(CO)(CNR)(PPh3)2, (R =p-tolyl) have been prepared by the action of bases on [RuH(CO)2(CNR)(PPh3)2]+ and [RuH(CO)(CNR)-(PPh3)3]+; protonation of Ru(CO)2(CNR)(PPh3)2 occurs specifically trans to isocyanide.