NEW BIS(DIPHENYLPHOSPHINO)METHANE-BRIDGED D(10)-D(10) HETEROBINUCLEAR COMPLEXES DERIVED FROM NI(CO)(2)(ETA(1)-PH(2)PCH(2)PPH(2))(2) AND NI-2(MU-CO)(CO)(2)(MU-PH(2)PCH(2)PPH(2))(2) - THE CRYSTAL-STRUCTURE OF NICU(CO)(2) (MU-PH(2)PCH(2)PPH(2))(2)(BH3CN)

Syntheses of the d(10)-d(10) ionic complexes [NiCu(CO)(2)(mu-dppm)(2)(MeCN)(2)]X (dppm = Ph(2)PCH(2)PPh(2), X = ClO4, BPh(4) or PF6), containing four-coordinate copper, and the related complex NiCu(CO)(2)(mu-dppm)(2) (BH3CN) from reactions of Ni(CO)(2)(eta(1)-dppm)(2) with copper(I) species are reported as is the crystal structure of the second of these compounds. This shows a tetrahedral arrangement about nickel(0), a slightly distorted trigonal planar arrangement about copper(I), a Ni-Cu distance [3.171(4) Angstrom] which is too great for significant metal-metal interaction, and a cradle type of arrangement for the Ni-Cu-dppm framework in the solid state. Attempts to prepare related d(10)-d(10) Ni(0)-M(I or II) (M = Ag, Au, Zn or Hg) complexes by similar methods were not successful but a Ni-Au complex of limited stability can be identified in related reactions involving Ni-2(mu-CO)(CO)(2)(mu-dppm)(2).