Fiber-Optic Infrared Spectroelectrochemistry of Some Dinitrosyl Iron Phosphine Complexes and an NMR Kinetics and Equilibrium Study of an Organic Nitroso Compound in Various Solvents

Abstract

This dissertation describes a study of some of the fundamental chemical properties of some dinitrosyl iron phosphine complexes and a study of the dimer-monomer equilibrium of 2-methyl-2-nitrosopropane in various solvents.

Chapter 2 describes the study of some dinitrosyl iron phosphine complexes. Dinitrosyl iron complexes (DNICs) have been invoked as viable entities that contribute towards the biological action of nitric oxide (NO). DNICs derive their basic functionality from the dinitrosyl Fe(NO)2 moiety. Thus, it is important to understand how ancillary ligands bound to the metal affect the fundamental properties of the Fe(NO)2 unit. We have prepared a homologous series of dinitrosyl iron phosphine complexes and characterized them by FTIR and 31P NMR spectroscopy, X-ray crystallography, cyclic voltammetry and fiber-optic infrared spectroelectrochemistry. We then determine and explain the observed trends in the data as a function of phosphine substitution.

Chapter 3 describes the study of a C-nitroso compound, namely the dimeric 2-methyl-2-nitrosopropane, in various solvents. Interest in the fundamental properties of C-nitroso compounds has been increasing due to the recent recognition of the roles they play in various biological processes (e.g., "shutting down" the activities of various heme enzymes). Our interest in the fundamental chemistry of C-nitroso compounds has led us to study the equilibrium established by the dimer 2-methyl-2-nitrosopropane containing a tertiary C-NO group. We have combined a kinetics and equilibrium study into a single project involving a series of solvents over a sufficient temperature range that allows for the calculation of thermodynamic data. The dependence of the rate and equilibrium constants on various solvent parameters is then determined.