Chemistry ETDs

Publication Date

7-9-2009

Abstract

In Chapter 1, a brief literature review on the chemistry of lanthanides (Ln) and actinides (An) is described. In addition, the coordination chemistry of lanthanides/actinides with various ligands comprised of organic backbones has also been described. In Chapters 2 and 3 the syntheses of oxazoline and benzoxazole ligands is described. Both ligands contain a hard donor group (P=O) and the nitrogen (N) atom from the heterocycle as a relatively softer donor atom. In Chapter 2 the oxazoline ligand was synthesized in two steps reaction that involves substitution with Ph2P group and oxidation of the phosphine into P=O by air. The target compound, 2-[(diphenylphosphinoyl)methyl]-4,5-dihydro-oxazole, 19 was fully characterized by spectroscopic methods. Single crystals suitable for X-ray diffraction of the target molecule were grown from a capped hot ethyl acetate solution for several hours. The coordination with lanthanides was demonstrated by isolation of a complex using Nd(III). Single crystal X-ray diffraction analysis of the Nd(III) complex shows bidentate bonding via the P=O group and N donor atom. In Chapter 3, a series of target benzoxazole based ligands 25a-25d are described. All ligands contain the hard P=O and nitrogen (N) donor groups. These ligands have been fully characterized using elemental analysis, mass spectrometry and spectroscopic analysis. Single crystals suitable for X-ray diffraction studies for 25a-25d were grown from different solvents. The coordination complexes were formed with Nd(III) and Yb(III). Single crystal X-ray diffraction studies were completed. Only 25a complex with Nd(III) reveals bidentate coordination via P=O and N groups, the rest show monodentate coordination via P=O group only. In Chapter 4 a syntheses and coordination summary that is described in Chapters 2 and 3 is provided. It is expected that some of the ligands prepared in this study may have the potential toward actinide(III) extraction, and this will be examined in future collaborative studies.

Project Sponsors

University of New Mexico, Chemistry Department and Department of Energy, Office of Basic Energy Sciences (DOE)- USA

Language

English

Keywords

Oxazoline, Benzoxazole, Ligands, Lanthanides, Coordination chemistry, Phosphine oxide

Document Type

Dissertation

Degree Name

Chemistry

Level of Degree

Doctoral

Department Name

Department of Chemistry and Chemical Biology

First Advisor

Paine, Robert Treat

First Committee Member (Chair)

Deck, Lorraine M., Gary W. and Richard A. Cooper, and Kemp

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