DINUCLEAR COMPLEXES OF RHODIUM(I) CONTAINING DIISOCYANIDE LIGANDS AND SOME OF THEIR PHOSPHINE DERIVATIVES

A series of organic diisocyanides [(1,3-diisocyanopropane, 1,4-diisocyanobutane, 1,5-diisocyanopentane, 1,6-diisocyanohexane, 1,3-bis(isocyanomethyl)benzene and 1,4-bis(isocyanomethyl)cyclohexane)] was found to rapidly react with [RhCl(CO)2]2 or [RhCl(C8H12)]2 to give the photosensitive complexes [Rh2(diisocyanide)4]2+ (1-6). Reaction between 1,8-diisocyanooctane and [RhCl(C8H12)]2 produces the monomeric cation [Rh(1,8-diisocyanooctane)2]+. Photochemical solvolysis reactions of complexes 1-2 are examined. Reaction of 1-7 with bis(disphenylphosphino)methane (DPM) displaces two diisocyanide ligands to give trans-[Rh2(diisocyanide)2(DPM)2]2+ (8-14), which may also be obtained from the reaction of the diisocyanide and trans-[RhCl(CO)(DPM)]2. Similarly, [Rh2(diisocyanide)2(PPh3)4]2+ (15-19) may be prepared from reaction between [Rh2(diisocyanide)4]2+ and triphenylphosphine or from the reaction of trans-[RhCl(CO)(PPh3)2] or [RhCl(PPh3)3] with the diisocyanide ligand. Complex 7 also reacts with triphenylphosphine and bis(diphenylphosphino)ethane(diphos) producing the complexes cis-[Rh(1,8-diisocyanooctane)(PPh3)2]+ (20) and cis-[Rh(1,8-diisocyanooctane)(diphos)]+ (21), respectively. © 1979.