Date of Award
1990
Degree Type
Dissertation
Degree Name
Doctor of Philosophy
Abstract
This thesis documents the chemistry of some homo- and heteronuclear cluster complexes of gold and platinum.;The reaction of (AuC{dollar}\equiv{dollar}C{dollar}t{dollar}-Bu) with the diphosphine ligands, CH{dollar}\sb2{dollar}(PR{dollar}\sb2{dollar}){dollar}\sb2{dollar} (R = Me, dmpm; R = Ph, dppm; R = {dollar}-{dollar}OMe, dmopm), yielded a number of complexes. Complexes ({dollar}t{dollar}-BuC{dollar}\equiv{dollar}C-Au-R{dollar}\sb2{dollar}PCH{dollar}\sb2{dollar}OR{dollar}\sb2{dollar}) (R = Me, Ph) were fluxional in solution. The crystal structures of (Au{dollar}\sb2{dollar}({dollar}\mu{dollar}-dmpm){dollar}\sb2{dollar}) X{dollar}\sb2\cdot{dollar}2H{dollar}\sb2{dollar}O (X = C{dollar}\ell{dollar}, I) were determined, as was that of (Au{dollar}\sb2{dollar}(C{dollar}\equiv{dollar}C{dollar}t{dollar}-Bu){dollar}\sb2{dollar}({dollar}\mu{dollar}-dppm)). Complex (CH{dollar}\sb2\{lcub}{dollar}P(MeO){dollar}\sb2{dollar}Au(C{dollar}\equiv{dollar}C{dollar}t{dollar}-Bu){dollar}\{rcub}\sb2{dollar}) oligomerized in chlorinated solvents to give (Au{dollar}\sb2{dollar}(C{dollar}\equiv{dollar}C{dollar}t{dollar}-Bu){dollar}\{lcub}\mu\sb3- {dollar}(MeO){dollar}\sb2{dollar}PCHP(OMe){dollar}\sb2\{rcub}{dollar}) {dollar}\sb3{dollar}, and then (Au{dollar}\sb8{dollar}C{dollar}\ell\sb2\{lcub}\mu\sb3- {dollar}(MeO){dollar}\sb2{dollar}PCHP(OMe){dollar}\sb2\{rcub}\sb2\{lcub}\mu\sb4- {dollar}(MeO){dollar}\sb2{dollar}PCP(OMe){dollar}\sb2\{rcub}\sb2{dollar}) {dollar}\cdot{dollar}CHC{dollar}\ell\sb3{dollar}. The structure of the octagold cage was determined by X-ray crystallography, and was shown to contain the first structurally characterized example of ({dollar}\mu\sb4- {dollar}R{dollar}\sb2{dollar}PCPR{dollar}\sb2{dollar}) {dollar}\sp{lcub}2-{rcub}{dollar} ligand. A reaction pathway to form the octagold complex is postulated.;The chemistry of homo- and heteronuclear complexes of platinum discussed are based on the triplatinum cluster, (Pt{dollar}\sb3{dollar}({dollar}\mu\sb3-{dollar}H)({dollar}\mu-{dollar}dppm){dollar}\sb3{dollar}) {dollar}\sp+{dollar}, 1. Auration of complex 1 with AuPPh{dollar}\sb3\sp+{dollar} gave (Pt{dollar}\sb3{dollar}({dollar}\mu\sb3-{dollar}H)({dollar}\mu\sb3-{dollar}AuPPh{dollar}\sb3{dollar})({dollar}\mu-{dollar}dppm){dollar}\sb3{dollar}) (PF{dollar}\sb6{dollar}){dollar}\sb2{dollar}, which can be deprotonated to (Pt{dollar}\sb3{dollar}({dollar}\mu\sb3-{dollar}AuPPh{dollar}\sb3{dollar})({dollar}\mu-{dollar}dppm){dollar}\sb3{dollar}) (PF{dollar}\sb6{dollar}) and then further aurated to (Pt{dollar}\sb3{dollar}({dollar}\mu\sb3-{dollar}AuPPh{dollar}\sb3{dollar}){dollar}\sb2{dollar}({dollar}\mu-{dollar}dppm){dollar}\sb3{dollar}) (PF{dollar}\sb6{dollar}){dollar}\sb2{dollar}. The reactions of these hetero bimetallic complexes with various main group reagents were also studied.;The reaction of tertiary phosphines and phosphites, L, with 1 yielded the clusters (Pt{dollar}\sb3{dollar}({dollar}\mu\sb3-{dollar}H)(L)({dollar}\mu-{dollar}dppm){dollar}\sb3{dollar}) (PF{dollar}\sb6{dollar}). The cluster complex (Pt{dollar}\sb3{dollar}({dollar}\mu\sb3-{dollar}H){dollar}\{lcub}{dollar}P(OMe){dollar}\sb3\{rcub}{dollar}({dollar}\mu-{dollar}dppm){dollar}\sb3{dollar}) (PF{dollar}\sb6{dollar}) was characterized by X-ray crystallography. These clusters contain an asymmetrically capping hydride ligand for which the spectroscopic parameters were obtained. The phosphine and phosphite ligands displayed a unique fluxionality which was deduced using multinuclear NMR data.;The triplatinum complex 1 can be protonated rapidly and reversibly by aq. HPF{dollar}\sb6{dollar}, to give (Pt{dollar}\sb3{dollar}({dollar}\mu\sb3-{dollar}H){dollar}\sb2{dollar}({dollar}\mu-{dollar}dppm){dollar}\sb3{dollar}) {dollar}\sp{lcub}2+{rcub}{dollar}, and (Pt{dollar}\sb3{dollar}({dollar}\mu\sb3-{dollar}H){dollar}\sb3{dollar}({dollar}\mu-{dollar}dppm){dollar}\sb3{dollar}) {dollar}\sp{lcub}3+{rcub}{dollar}. Use of CF{dollar}\sb3{dollar}COOH yielded an asymmetric complex, (Pt{dollar}\sb3{dollar}({dollar}\mu\sb3-{dollar}H)(H)({dollar}\mu-{dollar}dppm){dollar}\sb3{dollar}({dollar}\mu-{dollar}CF{dollar}\sb3{dollar}COO)) {dollar}\sp+{dollar}. These dihydrido complexes react with CO to quantitatively eliminate hydrogen and form (Pt{dollar}\sb3{dollar}({dollar}\mu\sb3-{dollar}CO)({dollar}\mu-{dollar}dppm){dollar}\sb3{dollar}) {dollar}\sp{lcub}2+{rcub}{dollar}, 2. They also react with various phosphine and phosphite ligands, L, to yield (Pt{dollar}\sb3{dollar}({dollar}\mu-{dollar}H)(H)(L)({dollar}\mu-{dollar}dppm){dollar}\sb3{dollar}) {dollar}\sp{lcub}2+{rcub}{dollar}. Phenyl phosphine, PPhH{dollar}\sb2{dollar}, reacted with 1 to yield (Pt{dollar}\sb3{dollar}({dollar}\mu\sb3-{dollar}PPh)(H)({dollar}\mu-{dollar}dppm){dollar}\sb3{dollar}) {dollar}\sp+{dollar}.;The chemistry of some tetraplatinum clusters was examined. The reaction of complexes 1 and 2 with the Pt(0) reagent, (Pt(CO){dollar}\sb2{dollar}(PPh{dollar}\sb3{dollar}){dollar}\sb2{dollar}), yielded (Pt{dollar}\sb4{dollar}({dollar}\mu- {dollar}H)({dollar}\mu- {dollar}CO){dollar}\sb2{dollar}(PPh{dollar}\sb3{dollar})({dollar}\mu- {dollar}dppm){dollar}\sb3{dollar}) {dollar}\sp+{dollar}, and (Pt{dollar}\sb4{dollar}({dollar}\mu- {dollar}CO){dollar}\sb2{dollar}(PPh{dollar}\sb3{dollar})({dollar}\mu- {dollar}dppm){dollar}\sb3{dollar}) {dollar}\sp{lcub}2+{rcub}{dollar}, respectively. The fluxionality of these clusters was deduced on the basis of variable temperature NMR data and by comparison with the previously characterized cluster (Pt{dollar}\sb4{dollar}({dollar}\mu- {dollar}H)({dollar}\mu- {dollar}CO){dollar}\sb2{dollar}({dollar}\mu- {dollar}dppm){dollar}\sb3{dollar}({dollar}\eta\sp1- {dollar}dppm)) {dollar}\sp+{dollar}.
Recommended Citation
Ramachandran, Ravindranath, "Homo- And Heteronuclear Clusters Of Platinum And Gold" (1990). Digitized Theses. 1899.
https://ir.lib.uwo.ca/digitizedtheses/1899