DINUCLEAR CYCLOMETALATED COMPLEXES OF PD-II WITH DIPHOSPHINES. X-RAY CRYSTAL-STRUCTURE OF =N])(2)-C6H4(PH(2)P(CH2)(3)PPH(2)-P,P)(2)][PF6](2)

Treatment of the cyclometallated halide-bridged complexes [1,4-{Pd[2,3 ,4-(MeO)(3)C6HC(H)=N](X)}2C6H4](2) (1a, 2a), [1,4-{Pd[2,4-(MeO)(2)C6H2 C(H)=N](X)}2C6H4](2) (1b, 2b), [1,4-{Pd[3-Me-4-MeOC6H2C(H)=N](X)}2C6H4 ](2) (1c, 2c), [1,4-{Pd[4,5-(OCH2O)C6H2C(H)=N](X)}2C6H4](2) (1d, 2b) ( X=Cl, Br) with ditertiary diphosphines in a complex/diphosphine 1:4 mo lar ratio and ammonium hexafluorophosphate gave the dinuclear cyclomet allated complexes Pd[2,3,4-(MeO)(3)C6HC(H)=N]}2C6H4(L-L)(2)][PF6](2) [ L-L=Ph(2)PCH(CH3)PPh(2), Ph(2)P(CH2)(2) PPh(2), 3a, 4a], Pd[2,4-(MeO)( 2)C6H2C(H)=N]}2C6H4(L-L)(2)][PF6](2), [L-L=Ph(2)PCH(CH3)PPh(2), Ph(2)P (CH2)(2)PPh(2), 3b, 4b] 3-Me-4-MeOC(6)H(2)C(H)=N]}2C6H4(L-L)(2)][Pf(6) ](2) [L-L=Ph(2)PCH(CH3)PPh(2), Ph(2)P(CH2)(n)PPh(2), n=2, 3, 3c, 4c, 5 c], -{Pd[4,5-(OCH2O)C6H2C(H)=N]}2C6H4(L-L)(2)][PF6](2) [L-L=Ph(2)PCH(C H3)PPh(2), Ph(2)P(CH2)(n)PPh(2), n=2, 3, 4, 3d, 4d, 5d, 6d]. The influ ence of ring size on the phosphorus chemical shift is discussed. The c ompounds were characterized by microanalysis (C, H, N), IR and P-31-{H -1} and H-1 NMR spectroscopy. The structure of the dinuclear cyclometa llated palladium(II) complex C(H)=N]}2C6H4{Ph(2)P(CH2)(3)PPh(2)-PP}(2) ][PF6](2) is described. There are two different crystallographic molec ules per asymmetric unit.