The synthesis and reactions of metal complexes of bis(diphenylphosphino)amine monoxides.

Chapter 1 reviews the literature concerning the principal synthetic routes to the bis(diphosphino)alkane monoxide ligands, their metal complexes and the use of these complexes in catalysis and formation of heterobimetallic metal complexes. Chapter 2 describes the synthesis of novel bis(diphenylphosphino)amine monoxide ligands, the data indicating both similarities and differences to related ligands. The isolation of a novel triphosphazane monoxide has also been achieved. Chapter 3 is concerned with the preparation and characterisation of transition metal complexes of the bis(diphenylphosphino)amine monoxides with palladium, rhodium, iridium, ruthenium, molybdenum and tungsten. The molecular structures of the complexes cis-[RhCl(CO){lcub}Ph2PN(R)P(O)Ph2{rcub}] (R=C6H4OMe-4) and [Rh(COD){lcub}Ph2PN(Ph)P(O)Ph2{rcub}][PF6] establish the presence of a slightly puckered five-membered chelate ring in both complexes. The complexes cis-[Mo(CO)4[Ph2PN(Ph)P(O)Ph2{rcub}2] and cis-[W(CO)4(pip)(Ph2PN(Ph)P(O)Ph2{rcub}] have been shown to contain non-chelating monodentate ligands from 31P-{lcub}1H{rcub} n.m.r. data. In Chapter 4 the reactions of the bis(diphosphino)amine monoxide metal complexes are discussed with particular reference to the oxidative addition reactions of the rhodium and iridium analogues. Attempts to form water-soluble complexes by the use of the biologically important Etmal and Memal ligands led to an investigation of the novel rhodium(I) complexes of these ligands and comparison with similar complexes in the literature containing the acac ligand. The final chapter describes the preparation of some metal complexes of the triphosphazane monoxide ligand (Ph2PNPh)2P(O)Ph with platinum, palladium, molybdenum and tungsten. Reactions of the platinum complexes and complexes of the type [PtCl2(P-P)] with esters of acetone dicarboxylic acid and amides containing activated hydrogen atoms in the presence of silver(I) oxide, leads to a variety of four-membered ring platinacycles. The 195Pt-{lcub}1H{rcub} n.m.r. spectra of some of the complexes are presented.