All ETDs from UAB

Advisory Committee Chair

Gary M Gray

Advisory Committee Members

Houston Byrd

Tracy P Hamilton

Christopher M Lawson

Aaron L Lucius

Sergey V Vyazovkin

Document Type

Dissertation

Date of Award

2016

Degree Name by School

Doctor of Philosophy (PhD) College of Arts and Sciences

Abstract

The synthesis, characterization, and hard/soft metal binding abilities of a series of novel phosphite- and phosphinite-functionalized transition metal complexes are reported. Many of these compounds have applications as molecular sensors or as alkene hydro-formylation catalysts. The first chapter investigates a series of cis-tetracarbonylmolybdenum(0) com-plexes prepared from α,ω-bis(phosphite)-polythioether ligands. Their syntheses have been optimized, and solid-state structures of the complexes, as well as one of the synthet-ic by-products, are reported. The abilities of the metallathiacrown ethers to bind MCl2 (M = Hg, Pt, Pd) have been assessed using 31P{1H} NMR spectroscopy and X-ray crystallog-raphy. These studies show that the compounds do not bind PdCl2, however most of the compounds do bind HgCl2 and PtCl2 to form 1:1 complexes with various coordination modes and binding mechanisms. The second chapter evaluates the effects of sulfur atoms in the ligands synthesized in Chapter 1 on styrene hydroformylation. Catalysis was carried out with monometallic Rh(I), homobimetallic Rh(I)-Rh(I), and heterobimetallic Rh(I)-Pt(II) complexes. The ob-served effects were highly ligand dependent, and a discussion of these dependencies is outlined based on the structure-property relationships reported in Chapter 1. The third chapter investigates the alkali metal cation binding abilities of a novel class of monodentate phosphite-lariat ether ligands and their cis-tetracarbonylmolybdenum(0) complexes. Their syntheses have been optimized, and Rh(I) complexes of the ligands have been evaluated as catalysts for the hydroformylation of styrene in both the absence and presence of Li+, Na+, and K+ containing salts. The cata-lytic data show distinct trends in salt:ligand ratios that result in increased catalytic activi-ties. These trends are then correlated with 31P{1H} and 1H NMR spectroscopic titration experiments with the cis-tetracarbonylmolybdenum(0) complexes that provide insight into the specific binding mechanisms associated with each complex. The final chapter outlines the total synthesis of a novel molecular gyroscope. The preparation of each synthetic intermediate has been optimized, and solid-state structures for each complex are reported. Eyring analyses of the intramolecular trans-cis isomeriza-tion of two of the intermediates are also reported, along with the attempted binding of Ni(II) to the product complex.

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