Kinetic studies on thiolato-ligand substitution reactions with halide ions of square-planar palladium(II) complex with bis(2-(diphenylphosphino)ethyl)phenylphosphine

摘要

The square-planar thiolato palladium(II) complex with a terdentate phosphine bound ligand, [Pd(pt)(p(3))](BF4) (p(3) = bis(2-(diphenylphosphino)ethyl)phenylphosphine, pt = 1-propanethiolate) has been synthesized and characterized by P-31 NMR spectroscopy. The solid state structure of [PdI(P-3)]I was determined by an X-ray crystal structure analysis. The kinetic parameters for the thiolato-ligand substitution reactions with halide ions, [Pd(Pt)(p(3))](+) +X- -->[PdX(p(3))](+) +Pt- (X- = Cl-, Br-, I-), in chloroform were obtained as follows: k(298) = 7.22, 1.68 and 10.1 x 10(-4) s(-1), DeltaHdouble dagger = 67+/-2, 56+/-2 and 63+/-3 kJ mol(-1) and DeltaSdouble dagger = -80+/-7, -128+/-6 and -92+/-11 J mol(-1) K-1, respectively. These kinetic results are compared with those for the corresponding reactions of the trigonal-bipyramidal complex with an analogous phosphine bound ligand, [Pd(Pt)(pp(3))](BF4) (pp(3) = tris(2-(diphenylphosphino)ethyl)phosphine). (C) 2002 Elsevier Science B.V. All rights reserved. [References: 16]