Structural investigations of nickel complexes. Part I. Crystal and molecular structure of cis-dichlorobis(1-benzyl-Δ3-phospholen)nickel(II)

Abstract

The crystal and molecular structure of the title compound has been determined by single-crystal X-ray analysis with 3112 independent reflections and refined to R 0·095. The crystals are monoclinic, space-group P2₁/c, with a= 10·40(2), b= 12·91(2), c= 18·00(3)Å, β= 112·67(10)°; Z= 4. The molecule has approximate C₂ symmetry and co-ordination around the nickel atom is tetrahedrally distorted square planar with mean Cl–Ni–P angles of 164·7°. A high trans-influence of the tertiary phosphine ligands is noted in the complex. The mean Ni–P [2·154(2)Å] and Ni–Cl [2·212(2)Å] bond lengths are respectively 0·12 shorter and 0·05 Å longer than the corresponding values derived from the sum of the covalent radii. The phospholen rings are puckered, mean C–P–C angle 94·0°± 0·4°, and the mean phosphorus atom displacement from the best plane through the ring carbon atoms is 0·385 Å.