This thesis describes the synthesis and coordination chemistry of self-assembled multidentate iron(II) phosphine complexes. Chapter 1 introduces the background to phosphine ligands, their properties, interactions with transition metals and applications. The chapter then discusses macrocyclic and medium ring P,N-containing ligands, as well as some water soluble phosphines. The chapter also introduces the novel self-assembled macrocyclic phosphine complex [FeL1(H2O)2]SO4 (1) and its tetradentate cyclic phosphine ligand L1. Chapter 2 describes the synthesis of [FeL1(H2O)2]SO4 (1) and its coordination chemistry with a variety of ligands, including halides, pseudo-halides, and CO. 57Fe labelled versions of complex 1 and the related dicarbonyl complex [FeL1(H2O)2]SO4 (9) were synthesised as models for the hydrogenase protein Hmd in a Nuclear Resonance Vibrational Spectroscopy study. Reactions were also undertaken to functionalise the hydroxymethyl groups in order to alter the properties of the complexes. The reaction of 1 with acetic anhydride afforded complex [Fe(L2)(k2-O2SO2)] (13), possessing the acylated ligand L2 and a coordinated sulfate ligand. The coordination chemistry of 13 was explored with a variety of neutral and anionic ligands, including halides, pseudohalides, carbonate, and CO. Electrochemical cyclic voltammetric investigations of L1 and L2 complexes were also explored. Chapter 3 reports the investigations carried out to explore the effect of altering the reagents of the self-assembly reaction. The self-assembly reaction to synthesise complex 1 was also attempted with copper(II), nickel(II), copper(II) and zinc(II) salts, as well as in the absence of a metal template, which all did not lead to the formation of any isolable species. The syntheses of the novel iron(II) complexes [Fe(L3)2(SO4)] (23) and cis-[Fe(L3)2Cl2] (24a) containing the new bidentate phosphine ligand L3 are also reported, as well as the coordination chemistry of 24a with a variety of ligands. The reaction of 24a with NaBH4 gave the trans hydride-chloride complex trans-[Fe(L3)2(H)Cl] (29). Electrochemical investigations of the L3 complexes were also carried out. Chapter 4 provides the experimental details for the reactions described in chapters 2 and 3.
- self assembly