Transition of trigonal-bipyramidal to square-planar geometries by oxidation of a coordinated tripodal polyphosphine in Pd(ii) and Pt(ii) complexes†
Abstract
The oxidation reactions of the unusual d8 trigonal-bipyramidal systems [MX(PP3)]X (M = Pd: X = Cl(1), Br(2), I(3); M = Pt: X = Cl(4), Br(5), I(6); PP3 = O functionalities of the resulting products. The oxidations with H2O2 required a higher concentration for Pd than Pt and occurred with formation of both ionic distorted square-planar compounds [MX(PP2PO)]X [M = Pd: X = Cl(7); M = Pt: X = Cl(10), Br(11)], that contain one dangling P
O group, and the less common neutral species [MX2(PP(PO)2] [M = Pd: X = Br(8), M = Pt: X = I(12)] showing MX2P2 environments and two P
O arms, or with release of all bound phosphorus from 3 to give OP(PO)3 (9). Although there was no evidence of the formation of neutral species with two Pt–Cl bonds and dissociation of one bound phosphorus by adding H2O2 or M′Cl (M′ = Cu, Ag) to 10, the interaction with [AuCl(tdg)] (tdg =
O and PAuCl arms and one chiral central phosphorus. Thus, while the
O group predicted by