Stabilizing reactive metal-ligand fragments: Development of multidentate monoanionic ligands

Chapter 1. An overview of the use of tetradentate monoanionic (TDMA) ligands in organometallic and bioinorganic chemistry is presented. The potential drawbacks and advantages of different ligand donor groups and motifs are outlined, setting up the foundation for the work to be presented in the following five chapters.;Chapter 2. A series of early transition metal complexes supported by the TDMA ligand BPPA is synthesized. The substitution chemistry of the metal-halide complexes is explored. The thermal stability of a tribenzyl zirconium complex is studied, and the nature of the resulting decomposition product is reported.;Chapter 3. The synthesis of the new multidentate monoanionic ligand [N2P2] is described, and the coordination chemistry of a series of first-row transition metal-halide complexes supported by the [N2P2] ligand is presented. Three distinct coordination modes are observed. Electrochemical and solid-state magnetic susceptibility data are also reported.;Chapter 4. Titanium and zirconium alkyl complexes are synthesized, and the thermal stability of the metal-alkyl compounds is explored. A change in coordination geometry of the [N2P2] ligand upon the formation of a cationic species is outlined. Low-valent titanium and zirconium species are generated, and their reactivity with dinitrogen and other substrates is presented.;Chapter 5. The substitution and reduction chemistry of a [N2P2] cobalt halide complex is presented. A four-coordinate Co(I) compound is isolated, and the results of reactivity studies with arylazides is outlined. The synthesis and resulting changes in coordination and reaction chemistry with the new ligand [N2P2tolyl] is described.;Chapter 6. Manganese and iron alkyl-, hydride-, and low-valent compounds are synthesized. The structural and spectroscopic properties of two new end-on bridging dinitrogen complexes are presented. Changes in reactivity within the reduced iron system are examined following the substitution of [N2P2] for [N2P2tolyl ].