Yuyang Wu

Date of Award


Degree Type


Degree Name

Doctor of Philosophy


Three new types of chalcogenate-bridged adamantane-like clusters of the zinc-group elements have been studied in detail: those with alkylthiolates as bridging ligands, formulated as (({dollar}\mu{dollar}-{dollar}\rm SAlk)\sb6(MX)\sb4\rbrack\sp{lcub}2-{rcub}{dollar} (Alk = Me, Et, 1-Pr, 2-Pr, 1-Bu, 2-Bu, c-{dollar}\rm C\sb6H\sb{lcub}11{rcub}{dollar}(Cy), or CH{dollar}\sb2{dollar}Ph (Bz); M = Zn, Cd, or Hg; X = Cl, Br, or I); those with phosphines as terminal ligands, formulated as (({dollar}\mu{dollar}-ER){dollar}\sb6{dollar}(CdPPh{dollar}\sb3)\sb{lcub}4-n{rcub}{dollar}(Cd){dollar}\sb{lcub}n{rcub}\rbrack \sp{lcub}2+{rcub}{dollar} (E = S or Se; R = 1-Pr, 2-Pr, 1-{dollar}\rm C\sb5H\sb{lcub}11{rcub}{dollar} (1-Pe), Cy, or Ph; n = 0, 1, or 2); and those with halides as bridging ligands, formulated as (({dollar}\mu{dollar}-ER){dollar}\sb{lcub}6-m{rcub}(\mu{dollar}-X){dollar}\sb{lcub}m{rcub}{dollar}(MX){dollar}\sb4\rbrack\sp{lcub}2-{rcub}{dollar} (E = S or Se; R = Et, 1-Pr, 2-Pr, 1-Bu, Cy, of Ph; m = 0, 1, or 2; X = Cl, Br, or I; M = Cd or Hg). In total, seventy-one new clusters have been isolated analytically pure; more than one hundred species have been characterized in solution by multinuclear magnetic resonance; and three representative crystal structures have been obtained by X-ray analysis (carried out by others).;In general, for the adamantane-like species, the metal chemical shift, {dollar}\delta\sb{lcub}\rm Cd{rcub}{dollar} or {dollar}\delta\sb{lcub}\rm Hg{rcub}{dollar}, varies with R in the order primary alkyl {dollar}>{dollar} secondary alkyl {dollar}>{dollar} phenyl, with X in the order Cl {dollar}>{dollar} Br {dollar}>{dollar} I, and with temperature in the order reduced T {dollar}>{dollar} ambient T. In a study of the mixed-metal clusters, (({dollar}\mu{dollar}-SAlk){dollar}\sb6{dollar}(MX){dollar}\sb{lcub}4-n{rcub}{dollar}(M{dollar}\sp\prime{dollar}X){dollar}\sb{lcub}n{rcub}{dollar}) {dollar}\sp{lcub}2-{rcub}{dollar}, (M/M{dollar}\sp\prime{dollar} = Cd/Zn, Cd/Hg, or Hg/Zn), {dollar}\delta\sb{lcub}\rm Cd{rcub}{dollar} varies with n in the order 0 {dollar}>{dollar} 1 {dollar}>{dollar} 2 {dollar}>{dollar} 3 in Cd{dollar}\sb{lcub}4-n{rcub}{dollar}Zn{dollar}\sb{lcub}n{rcub}{dollar} or Cd{dollar}\sb{lcub}4-n{rcub}{dollar}Hg{dollar}\sb{lcub}n{rcub}{dollar} mixtures, while {dollar}\delta\sb{lcub}\rm Hg{rcub}{dollar} varies with n in the order {dollar}0\ \ 1\ >\ 2\ >\ 3{dollar} in Hg{dollar}\sb{lcub}4-n{rcub}{dollar}Zn{dollar}\sb{lcub}n{rcub}{dollar} mixture. For the mixed-halide clusters, (({dollar}\mu{dollar}-SPr{dollar}\sp{lcub}\rm i{rcub})\sb6{dollar}(CdX){dollar}\sb{lcub}4-n{rcub}{dollar}(CdX{dollar}\sp\prime)\sb{lcub}n{rcub}{dollar}) {dollar}\sp{lcub}2-{rcub}{dollar} (X/X{dollar}\sp\prime{dollar} = I/Br, I/Cl, or Br/Cl), it has been shown that when X is heavier than X{dollar}\sp\prime,\ \delta\sb{lcub}\rm Cd{rcub}{dollar} varies with n in the order {dollar}0\ <\ 1\ <\ 2\ <\ 3{dollar} for CdX site, and in the order {dollar}1\ <\ 2\ <\ 3\ <\ 4{dollar} for CdX{dollar}\sp\prime{dollar} site. In (({dollar}\mu{dollar}-{dollar}\rm ER)\sb6(Cd\sb{lcub}A{rcub}PPh\sb3)\sb{lcub}4-n{rcub}(Cd\sb{lcub}B{rcub})\sb{lcub}n{rcub}\rbrack \sp{lcub}2+{rcub},\ \delta\sb{lcub}Cd{rcub}{dollar} varies with n in the order {dollar}0\ <\ 1\ <\ 2{dollar} for Cd{dollar}\sb{lcub}\rm A{rcub}{dollar} or Cd{dollar}\sb{lcub}\rm B{rcub}{dollar}. Importantly, for Cd{dollar}\sb{lcub}\rm B{rcub}{dollar}, the PPh{dollar}\sb3{dollar}-free site, the terminal position can be occupied by OClO{dollar}\sb3\sp-{dollar} giving tetrahedral coordination geometry about the Cd. In (({dollar}\mu{dollar}-ER){dollar}\sb{lcub}6-m{rcub}(\mu{dollar}-X{dollar}\sb{lcub}m{rcub}{dollar}(MX{dollar}\sb4{dollar}) {dollar}\sp{lcub}2-{rcub}{dollar}, halides participate in bridging. When m = 2, the two bridging halides prefer to form a trans-({dollar}\mu{dollar}-X){dollar}\sb2{dollar} structure. These results provide model data for studies on metallothioneins and other biological systems with metal-cysteine sites.



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.