Date of Award
Doctor of Philosophy
Pt(,2)((mu)-dppm)(,2)Cl(PPh(,3)) ('+) is formed from a rate-limiting bimolec- ular reaction of PPH(,3) with Pt(,2)((mu)-dppm)(,2)Cl(,2) in CH(,2)Cl(,2). Alternatively, it and its bromo and chloro derivatives can be formed from the reaction of halides with Pt(,2)((mu)-dppm)(,2)-PPh(,3))(,2) ('2+) by (a) rate-limiting PPH(,3) dissociation, or (b) rate-limiting Pt(,2)((mu)-dppm) ring opening at a Pt-P bond. Formation of product by (b) occurs after the formation of two observable intermediates, one of which, Pt(,2)((eta)('2)-dppm)((mu)-dppm)-X(PPh(,3)) ('+), is readily characterized by ('31)P ('1)H NMR spectroscopy. Rates of these ligand substitution reactions are very sensitive to the anions present in solution;Atropisomers due to hindered rotation around the Pt-PPh(,3) bond of Pt(,2)((mu)-dppm)(,2)Cl(PPh(,3)) ('+) are caused by phenyl-phenyl repulsions and can be distinguished by ('31)P ('1)H NMR spectroscopy. Such repulsions also retard the rate of positional interchange of axial and equatorial substituents on its Pt(,2)((mu)-dppm)(,2) ring as observed by ('1)H NMR spectroscopy;Several correlations betwee ('195)Pt-('31)P coupling constants and Pt-P and Pt-Pt bond lengths were observed;The synthesis, characterization, and reactivity of Pt(,2)((mu)-dppm)(,2)Cl (,2)(di-(eta)('2)-P(,4)) ('2+) is reported. This complex is a dimer of platinum dimers bridged by tetra-phosphorus. One platinum of each dimer is bound to two phosphorus atoms of P(,4);The formation and reactivity of the metal-carbon bonds in benzylcobalamin and chromium alkyls, (H(,2)O)(,5)CrR('2+); R = CH(,2)Ph, CH(CH(,3)) OC(,2)H(,5), CH(,2)OCH(,3) , were also investigated; ('1)Doe Report IS-T-1165. This work was performed under contract W-7405-Eng-82 with the Department of Energy.
Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/
Reed John Blau
Blau, Reed John, "Formation and reactivity of metal-ligand bonds: platinum(I) dimers and cobalt and chromium alkyls " (1985). Retrospective Theses and Dissertations. 7822.