UNSYMMETRICAL DINUCLEAR RHODIUM COMPLEXES WITH ARSANYL- AND PHOSPHANYLARYLTHIOLATO LIGANDS [Rh(mu-S-2-EPh2C6H4-kappa S-2,E)(2)Rh(cod)] (E = As, P)

The heteroditopic ligands 1-EPh2-2-SHC6H4 (E = P, As) react with [{RhCl(cod)}(2)] to give [Rh(mu-S-2-EPh2C6H4-kappa S-2,E)(2)Rh(cod)] (cod = 1,5-cyclooctadiene, 1: E = As, 2: E = P), in which the two rhodium atoms are bridged by the thiolato groups of the ligands. One rhodium atom is coordinated by both ligands (kappa S-2,E) and the other rhodium atom by an additional 1,5-cyclooctadiene molecule, resulting in square-planar coordination geometry of both rhodium(I) centres. Theoretical studies confirmed the existence of metal- metal interactions between the two rhodium atoms of both 1 and 2. Complex 1 is active in the hydrogenation of olefins.