| This thesis describes a study of mononuclear and binuclear dimethylplatinum(II) complexes in oxidative addition, protonolysis, and C-H bond activation chemistry.;Oxidation of the complex [PtMe2(DPA)] by H2O 2 generates [Pt(OH)2Me2(DPA)], (DPA = 2,2'-dipyridyl-amine), which undergoes a remarkable form of self-assembly through hydrogen bonding in the solid state. There are cyclic tetramer units formed by head-to-head association between pairs of hydroxyl groups, and cyclic hexamer units formed by head-to-tail association between NH and OH groups. These building blocks then self-assemble to form a complex network structure containing large cavities, occupied by disordered solvent molecules.;The complexes [PtMe2(NN)] (NN = DPK, DPA) are protonated by acids HX at low temperature to give hydridoplatinum(IV) complexes which can exist in two isomeric forms with H trans to X or N. The structure of [PtHClMe2(DPK)] was determined crystallographically. The hydridoplatinum(IV) complexes reductively eliminate methane at room temperature in solution. In CD3OD solution, extensive H/D exchange occurs into the Pt-Me groups and CH4 product at low temperature, indicating very easy reversibility of the exchange between hydrido(methyl)platinum(IV) and (methane)platinum(II) complexes. Similar, but more complex reactions occurred for binuclear complexes [Pt2Me4(1,3-BAIB)] [BAIB = C6H4(CH=NCH 2CH2NMe2)2], and [Pt2Me 4(1,4-BAIB)] when reacted with acids.;The reaction of [PtMe2(DPK)] with excess HOTf gave an aqua complex or a binuclear hydroxo complex depending on the experimental conditions.;The complex [PtMe2(DPK)] (DPK = di-2-pyridyl ketone), undergoes easy oxidative addition with MeI, N-chlorosuccimmide, and [FN(CH2CH 2)2NCH2Cl][BF4]2 to give platinum(IV) complexes. Several oxidation reactions were found to occur with coordination of solvent. In several cases, the ketone group of the DPK ligand took part in the reactions.;The complex [Pt2Me4(1,3-BAIB)] undergoes oxidative addition with MeOTf to give, after recrystallization from moist solvent, the diplatinum(IV) aqua complex [{PtMe3(OH2)}2(1,3-BAIB)](OTf) 2, which has the anti stereochemistry of the two aqua ligands and which forms a dimer of dimers structure in the solid state through hydrogen bonding between aqua ligands and triflate anions.;The reactions of [PtMe2(NN)] and B(C6F5) 3/H2O in CF3CH2OH solution with arenes Ar-H gives [PtAr{O(H)B(C6F5)3}(NN)] if the bis(pyridyl) ligand NN forms a 6-membered ring, but not a 5-membered ring: methyl substituted arenes give selectivity for metallation meta > para >> ortho but methoxy substituted arenes give ortho >> meta, para . |
