STRUCTURAL-ANALYSIS OF ORTHO-PHENYLENEBIS(DIISOPROPYLPHOSPHINE) COMPLEXES OF NICKEL(II), PALLADIUM(II), AND PLATINUM(II)

The o-phenylenebis(diisopropylphosphine) (1) chelated dichloro complexes of group 10 (VIIIB), [o-C6H4(iPr2P)2]MCl2, where M = Ni (2a), Pd (2b), and Pt (2c), were prepared and characterized by NMR spectroscopy and single-crystal X-ray diffraction. The crystal structures of the three complexes are isomorphous. The nickel complex (2a) as typical crystallizes in the monoclinic space group P21/c, with a = 9.376 (2) Å, b = 12.755 (4) A, c = 18.31 (3) Å, β = 104.39 (6)°, and Z = 4. Least-squares refinement of 3191 observed reflections with I > 1.5σ(7) gave final R = 0.034 and Rw = 0.029. The metal is seated at the center of a square-planar disposition with the phosphine in the cis coordination. The benzene plane of 1 and the complex plane are roughly coplanar with their dihedral angle being 0.49 (8)°. The four isopropyl groups of 1 are symmetrically arranged out of the molecular plane and comprise two sets of methyl groups with each set containing four methyls in magnetic equivalence. © 1990, American Chemical Society. All rights reserved.