A new series of dimetallic cationic cyclopentadienyl-phosphine-bridged complexes of rhodium(II) and iridium(II)

Abstract

The complexes [M^I(C₅H₄PPh₂)(CO)]₂[M = Rh (1a) or Ir (1b)] were chemically oxidized, affording the synthesis of a novel series of cationic dimetallic bridged complexes of divalent rhodium and iridium, [M^II(C₅H₄PPh₂)₂L]₂²⁺[L = CO (2a, 2b), pyridine (M = Rh)(4a), P(OMe)₃(M = Rh)(7a), solvent (5a, 6a, etc.)]; surprisingly, the new double-bridging system C₅H₄PPh₂ allows both a long metal–metal distance [4.3029(6)Å] in (1a) and a short metal–metal bond [2.7796(9)Å] in (4a) while its change of conformation leads the terminal ligand L on each metal site of (4a) to adopt an interesting cisoid mutual disposition.