A rare example of a di-cationic hydrido carbonyl tetra-nuclear cluster, [H2Rh2Pt2(CO)7(PPh3)3]2+

Abstract Addition of excess CF 3 CO 2 H (HTFA) to [Rh 2 Pt 2 (CO) 7 (PPh 3 ) 3 ], I , under nitrogen results in the formation of a salt ( X 2+ Y 2− ) , which contains only the second example of a di-cationic carbonyl hydride tetra-nuclear cluster , [H 2 Rh 2 Pt 2 (CO) 7 (PPh 3 ) 3 ] 2+ , X 2+ , and a presently partially characterized polymetallic anion Y 2− . The di-cation X 2+ has been characterized by mass spectrometry and a variety of multinuclear NMR methods. Since there is no difference in the electron count for I and X 2+ , it is probable that both I and X 2+ adopt similar butterfly metallic frameworks with a Rh–Rh hinge; in X 2+ , there are two bridging hydrides to the same wing-tip Pt but the phosphine site occupancies on the Rh 2 Pt 2 -framework in I and X 2+ are different.