COORDINATION CHEMISTRY OF [CH2(PPH2)(P(Y)R2)] AND [CH(PPH2)(P(Y)R2)]-, Y = S OR SE, R = PH OR (T)BU RHODIUM, IRIDIUM AND RUTHENIUM COMPLEXES - C-13, P-31, AND SE-77 NMR-STUDIES - AND THE CRYSTAL AND MOLECULAR-STRUCTURES OF [IR(COD)(CH2(PPH2)(P(S)TBU2)-P,S)]BF4.CHCL3, [RH(COD)(CH2(PPH2)(P(S)TBU2)-P,S)]CLO4.CH2CL2, [RH(COD)(CH(PPH2)(P(S)PH2)-P,S)], AND [RUCL2(P-CYMENE)(CH2(PPH2)(P(S)PH2)-P)].CH2CL2

Reactions of the chloro-bridged complexes, [M2Cl2(cod)2], M = Ir or Rh , COD - cyclooctadiene, with CH2(PPh2)(P(Y)R2), Y = S or Se, R = Ph or (t)Bu, provide a synthetic route to the cations, [M(cod){CH2(PPh2)(P( Y)R2)-P,S}]+, which are isolated as fluoroborate or perchlorate salts. Treatment of these products with sodium hydride results in facile dep rotonation to the neutral complexes, [M(cod){CH(PPh2)(P(Y)Ph2)-P,S}], and when Y = S, the neutral complexes are also accessible via reaction s of [M2Cl2(cod)2] with Li[CH(PPh2)(P(S)R2)]. Reactions of the cations , [M(cod)(CH2(PPh2)(P(S)(t)Bu2)-P,S}]+ with other ligands, Lg = (CO)2, (CN(t)Bu)2, or bis(diphenylphosphino)methane (dppm), result in displa cement of cod to form [M(Lg){CH2(PPh2)(P(S)(t)Bu2)-P,S}]+. Ruthenium c omplexes of CH2(PPh2)(P(S)Ph2) are accessible via similar bridge cleav age reactions using [Ru2Cl4L2], L = benzene or p-cymene. These complex es are characterized by complete C-13, P-31, and Se-77 nuclear magneti c resonance (NMR) studies and by four crystal structure determinations . The complexes [Ir(cod)(CH2(PPh2)(P(S)(t)Bu2)-P,S}]BF4 . CHCl3 (1), [ Rh(cod)(CH2(PPh2)(P(S)(t)Bu2)-P,S}]ClO4 . CH2Cl2-(2), [Rh(cod)(CH(PPh2 )(P(S)Ph2)-P,S}] (3) and [RuCl2(p-cymene)(CH2(PPh2)(P(S)Ph2)-P}] . CH2 Cl2.(4) crystallize in the P1BAR (No. 2) space group (Z = 2) with resp ective unit cells: a = 12.307(7) angstrom, b = 14.743(8) angstrom, c = 10.877(6) angstrom, alpha = 74.42(5), beta = 107.65(6)-degrees, gamma = 105.47(5)-degrees; a = 12.163(1) angstrom, b = 14.56(1) angstrom, c = 10.560(1) angstrom, alpha = 77.69(1), beta = 74.54(1)-degrees, gamm a = 77.01(1)-degrees; a = 10.650(4) angstrom, b = 13.327(4) angstrom, c = 10.419(3) angstrom, alpha = 90.60(3)-degrees, beta = 102.64(3)-deg rees gamma = 83.15(3)-degrees; a = 11.217(2) angstrom, b = 17.124(3) a ngstrom, c = 10.412(2) angstrom, alpha = 90.58(1)-degrees, beta = 112. 29(2)-degrees, gamma = 97.53(2)-degrees. Complexes 1-3 all contain bid entate P,S-bonded ligands occupying two coordination positions of an a pproximately square planar metal centre. In each case, the coordinatio n is completed by two double bonds of a cod ligand. In contrast, compl ex 4 contains a monodentate P-bonded ligand.