title: Five-coordinate Pd(II) orthometallated triarylphosphite complexes.
abstract: The reaction of the orthopalladated triarylphosphite complexes [{Pd(mu-Cl){kappa(2)-P,C-P(OC(6)H(2)-2,4-R(2))(OC(6)H(3)-2,4-R(2))}(2)] (R = H, (t)Bu) with bis(2-diphenylphosphinoethyl)phenylphosphine leads to a five-coordinate palladium(II) (R = H) and a mixture containing four-and five-coordinate species (R = (t)Bu). The crystal structure of the five-coordinate species [Pd{kappa(2)-P,C-(P(OC(6)H(4))(OC(6)H(5))(2)}{bis(2-diphenylphosphinoethyl)phenylphosphine}][SbF(6)] is presented. This complex reacts with hydrogen peroxide or [AuCl(tht)] to give four-coordinate complexes in which the displaced phosphine residue is either oxidised or coordinated to gold chloride; this demonstrates that the five-coordinate complexes are labile in solution. By contrast, the reactions of the dimeric precursors with 1,1,1-tris(diphenylphosphinomethyl)ethane give four-coordinate complexes in the solid state, although evidence is presented that the smaller phosphite-containing system is five-coordinate at room temperature or higher in solution.
authors.affiliation: School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK. r.bedford@bristol.ac.uk
authors.forename: Robin B
authors.initials: RB
authors.lastname: Bedford
authors.forename: Michael
authors.initials: M
authors.lastname: Betham
authors.forename: Craig P
authors.initials: CP
authors.lastname: Butts
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Coles
authors.forename: Marica
authors.initials: M
authors.lastname: Cutajar
authors.forename: Thomas
authors.initials: T
authors.lastname: Gelbrich
authors.forename: Michael B
authors.initials: MB
authors.lastname: Hursthouse
authors.forename: P Noelle
authors.initials: PN
authors.lastname: Scully
authors.forename: Stephen
authors.initials: S
authors.lastname: Wimperis