Item – Theses Canada

​
OCLC number
46496941
Author
Yang, Li Wei.
Title
Coordination chemistry of lanthanides with multidentate ligands.
Degree
Ph. D. -- University of British Columbia, 1995
Publisher
Ottawa : National Library of Canada = Bibliothèque nationale du Canada, 1996.
Description
2 microfiches.
Notes
Includes bibliographical references.
Abstract
A number of potentially heptadentate $\rm N\sb4O\sb3$ and nonadentate/dinucleating $\rm N\sb6O\sb3$ ligands are reported: tris(((2-hydroxy-3-methoxybenzyl)amino)ethyl)amine (H$\sb3$(3-MeOaea)), 2-($2\sp\prime$-hydroxyphenyl)-1,3-di ($3\sp\prime$-aza-$4\sp\prime$-(2$\sp{\prime\prime}$-hydroxy-$5\sp{\prime \prime}$-halophenyl)-prop-$4\sp\prime$-en-$1\sp\prime$-yl) -1,3-imidazolidine (H$\sb3$Xapi, X = H, Cl, Br), N, N$\sp\prime,$ N$\sp{\prime\prime\prime}$-tris(2-hydroxybenzyl)triethylenetetraamine (H$\sb3$(1,2,4-btt)), and its acetone adduct 1-($2\sp\prime$-hydroxybenzyl)-2,2-dimethyl-3- ($3\sp\prime,6\sp\prime$-diaza-$3\sp\prime$-($2\sp{\prime \prime}$-hydroxybenzyl)-$7\sp\prime$-$(2\sp{\prime\prime}$-hydroxy phenyl)-heptyl) -1,3-imidazolidine (H$\sb3$(1,2,4-ahi)), H$\sb3$dha$\sb3$tren, and 1,4,7-tris(((2-hydroxy-5-bromobenzyl)amino)propyl)-1,4,7-triazacyclononane (H$\sb3$Brapt). The Schiff base ligands H$\sb3$Xapi (X = H, Cl, Br) are the products of the condensation reaction of triethylenetetraamine (trien) with 3 equiv of unsubstituted or substituted salicylaldehyde. The Schiff base H$\sb3$(dha$\sb3$tren) is prepared by the reaction of the tripodal tris(2-aminoethyl)amine (tren) and dehydroacetic acid. All the amine phenol ligands H$\sb3$(3-MeOaea), H$\sb3$(1,2,4-btt) and H$\sb3$(1,2,4-ahi), and H$\sb3$Brapt are the KBH$\sb4$ reduction products of the Schiff bases derived from the reactions of tren with 3 equiv of o-vanillin, trien with 3 equiv of salicylaldehyde, and 1,4,7-tris(3-aminopropyl)-1,4,7-triazacyclononane (taptacn) with 3 equiv of 5-bromosalicylaldehyde, respectively. A series of mononuclear, homodinuclear, and heterodinuclear (with copper) lanthanide complexes with the aforementioned ligands were synthesized. The reactions of lanthanide nitrates with one equiv of $\rm N\sb4O\sb3$ ligands produce mononuclear nine-coordinated complexes, (Ln(H$\sb3$L)(NO$\sb3)\sb3$) (H$\sb3$L = $\rm N\sb4O\sb3$ ligands), wherein the ligand adopts a tridentate capping coordination mode. The $\rm N\sb6O\sb3$ ligand H$\sb3$Brapt reacts with lanthanide triflates to give 1:1 complexes. In the presence of a base (sometimes in the absence of a base), other different coordination geometries are formed (depending on the ligand framework, rigidity, cavity size, and donor atom number): the six-coordinate bis(ligand) bicapped complexes (Ln(H$\sb3$(3-MeOaea))$\sb2$) (NO$\sb3)\sb3;$ the mononuclear seven-best viewed as a monocapped square antiprism. The crystal structure of the hydrolyzed H$\sb3$dha$\sb3$tren is also reported, indicating that the ligand has a keto-enamine form.
ISBN
0612060888
9780612060883