CRYSTAL AND MOLECULAR-STRUCTURE OF 2,3-ETA2-(1,4-DIMETHOXYBUT-2-YNE)BIS(TRICYCLOHEXYLPHOSPHANE)NICKEL(0), (CY3P)2NI(MEOCH2C=CCH2OME) - INFLUENCE OF PHOSPHANE LIGANDS ON ACETYLENE COMPLEXATION IN NICKEL(0) COMPLEXES

The crystal and molecular structure of 2,3-η2-(1,4-dimethoxybut-2-yne)bis(tricyclohexylphosphane )nickel(0) has been determined by an X-ray diffraction study. The complex crystallizes in the triclinic space group P1 with a 10.523(4), b 11.740(2), c 19.070(5) Å, α 85.21(2), β 86.44(3), γ 65.16(2)°, Z = 2. The structure was solved by the heavy-atom method and refined to R = 0.044. The coordination geometry at the nickel atom is trigonal-planar. The structure of (Cy3P)2Ni(MeOCH2C2CH 2OMe) is compared with that of the previously described triphenylphosphane analog (Ph3P)2Ni(MeOCH2C2CH2 OMe). The influence of different phosphane ligands on acetylene complexation in nickel(0) complexes is discussed. © 1990.