Browsing by Author "Bushnell, Gordon W."

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    Coordination chemistry of [CH2(PPh2) (P(Y)R2)] and [CH(PPh2)(P(Y)R2)]−, Y = S or Se, R = Ph or tBu: rhodium, iridium and ruthenium complexes; 13C 31P, and 77 Se 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,SClO4 · CH2Cl2 [Rh(cod)CH(PPh2) (P(S)Ph2)-P,S] and [RuCl2(p-cymene)CH2(PPh2)(P(S) Ph2) -P] · CH2Cl2
    (1992) Browning, Jane; Bushnell, Gordon W.; Dixon, Keith R.; Hilts, Robert
    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 tBu, 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 deprotonation to the neutral complexes, [M(cod)CH(PPh2)(P(Y)Ph2)-P,S)], and when Y  S, the neutral complexes are also accessible via reactions of [M2Cl2(cod)2] with Li[CH(PPh2)(P(S)R2)]. Reactions of the cations, [M(cod)CH2(PPh2)(P(S)tBu2)-P,S)]+ with other ligands, Lg  (CO)2, (CNtBu)2, or bis(diphenylphosphino)methane (dppm), result in displacement of cod to form [M(Lg)(CH2(PPh2)(P(S)tBu2)-P,S]+. Ruthenium complexes of CH2(PPh2)(P(S)Ph2) are accessiblevia similar bridge cleavage reactions using [Ru2Cl4L2], L  benzene or p-cymene. These complexes are characterized by complete 13C, 31P, and 77Se nuclear magnetic resonance (NMR) studies and by four crystal structure determinations. The complexes [Ir(cod)(CH2(PPh2)(P(S)tBu2)-P,S]BF4·CHCl3 (1), [Rh(cod)(CH2(PPh2)(P(S)tBu2)-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]· CH2Cl2 (4) crystallize in the P (No. 2) space group (Z  2) with respective unit cells: a = 12.307(7) Å, b = 14.743(8) Å, c = 10.877(6) Å, α =74.42(5)°, β = 107.65(6)°, γ = 105.47(5)°; a = 12.163(1) Å, b = 14.56(1) Å, c = 10.560(1) Å, α = 77.69(1)°, β = 74.54(1)°, γ = 77.01(1)°; a = 10.650(4) Å, b = 13.327(4) Å, c = 10.419(3) Å, α = 90.60(3)°, β = 102.64(3)°, γ = 83.15(3)°; a = 11.217(2) Å, b 17.124(3) Å, c = 10.412(2) Å, α = 90.58(1)°, β = 112.29(2)°, γ = 97.53(2)°. Complexes 1–3 all contain bidentate P,S-bonded ligands occupying two coordination positions of an approximately square planar metal centre. In each case, the coordination is completed by two double bonds of a cod ligand. In contrast, complex 4 contains a monodentate P-bonded ligand.
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    Coordination chemistry of [CH{P(S)Ph2}2]−: x-ray diffraction studies of S,S-chelate complexes of iridium and rhodium
    (1992) Browning, Jane; Bushnell, Gordon W.; Dixon, Keith R.; Hilts, Robert
    Reactions of the chloro-bridged complexes, [M2Cl2(cod)2], M  Ir or Rh, with CHR(P(S)Ph2)2, R  H or Me, provide a synthetic route to the cations, [M(cod){CHR(P(S)Ph2)2-S,S}]+, which are isolated as fluoroborate or perchlorate salts. Treatment of these products with sodium hydride results in facile deprotonation to the neutral complexes, [M(cod){CR(P(S)Ph2)2-S,S}], and when R  H, the neutral complexes are also accessible via reactions of [M2Cl2(cod)2] with Li[CH{P(S)Ph2)2]. The complexes, [Ir(cod){CH(P(S)Ph2)2-S,S}], and [Rh(cod){CH(P(S)Ph2)2-S,S}], crystallize in the P1 (No. 2) space group (Z = 2) with respective unit cells: a = 11.570(4), b = 15.122(2), c = 9.919(3) Å, α = 79.86(4), β = 64.87(3), γ = 97.94(4)°; and α = 11.571(16), b = 15.078(2), c = 9.869(2) Å, α = 100.16(1), β = 64.97(1), γ = 82.10(1)°. Both structures consist of puckered 6-membered rings formed by coordination of the disulfide ligands via two sulfur atoms to the metal center. The rings lie in distorted boat conformations with the prows occupied by one sulfur and one phosphorus and the metal atoms in one side.