Main group metal complexes supported by N,N'-bidentate ligands: synthetic and catalytic investigations

The work presented in this thesis is divided in to six chapters. Chapter 1 introduces the two main classes of ligands utilised in the research presented here and gives a brief account of the Tishchenko reaction. Chapter 2 describes the synthesis and characterisation of several new examples of amidinate, guanidinate and phosphaguanidinate complexes of magnesium. A number of these compounds are then examined for their activity as pre-catalysts for the Tishchenko reaction in Chapter 3. This chapter includes the screening of pre-catalysts for the synthesis of benzyl benzoate from benzaldehyde, preliminary mechanistic studies and examination of the scope of the reaction using examples of primary, secondary, tertiary and quaternary aliphatic aldehydes. Chapter 4 is a deviation from the main theme of this thesis and reports the synthesis of the first true ‘phospha-Grignard’ reagent. Preliminary reactivity studies with group 4 metallocenes, MCp2Cl2 (M = Ti, Zr), are also described. Chapter 5 explores the reactivity of the cyclic bis(amino)stannylene Sn{NAriPr}2SiMe2 with platinum-chloride species PtCl2(PPh3)2, PtCl2(COD), [PtCl(µ-Cl)(PEt3)]2 and PtCl2. In addition, one of the resultant Pt-Sn complexes is examined for its activity as a catalyst for the hydroformylation of 1-hexene. Finally, Chapter 6 describes the synthesis of the antimony and bismuth complexes supported by the dianionic bis(amido)silane ligand [Me2Si{NAriPr}2]2-.