| Summary: | Masters Degree. University of KwaZulu-Natal, Pietermaritzburg. Chapter 1 setves as an introduction to the synthesis and characterisation of copper(!), silver(!) and gold(!) complexes of the 2,6-bis( diphenylphosphino )pyridine { (Ph2P)2py}, phenylbis(2- pyridyl)phosphine {PhP(py)2 } and 2, 7-bis( diphenylphosphino )-4-methylnaphthyridine { (Ph2P)2menapy} ligands. A review of all the transition metal complexes of these ligands is presented. Particular attention is given to the modes of coordination that these ligands may adopt when coordinating to a transition metal. Chapter 2 describes the reactions of the (Ph2P)2py ligand with [Cu(MeCN)4](PF 6), [Cu( Tl 2- bipy)(MeCN)2J(PF 6), [Ag(COD)2](BF4) and [Ag(ri 2-bipy)(COD)](BF4) which result in the formation of the dinuclear ligand-bridged complexes [Cu2{μ-(Ph2P)2py}3](PF6) 2 (1), [Cu2{μ( P h2P)2PY }z( Tl 2 -bipy )z](PF 6)2 (2 ). [ Agz { μ -(Ph2P)2PY} 3)(BF 4)2 (3) and [ Ag2 { μ-(Ph2P)2PY} z( Tl 2 - bipy)2](BF4 ) 2 (4) respectively. The X-ray crystal structures of 1 and 3 reveal that the three (Ph)>)ipy ligands bridge the two metal atoms coordinating soley through their phosphorus atoms with the result that each metal atom has a trigonal geometry. The nitrogen atoms of the pyridines are left free resulting in a fairly open cavity in the centre of the complex cation. The cavity sizes are calculated to be 4.9 and 5.3 A for the copper and silver complexes respectively. It is suggested that these open cavities should be able to bind metal ions such as Cu~ and Ag+. Absorption and emission spectra were recorded for both complexes 1 and 3 and the effects of the addition of Cu+ and Ag+ ions on the emission spectra are discussed. These studies reveal that the emission spectra are indeed perturbed upon the addition of metal ions. The X-ray crystal structure of2 has been detennined confirming the presence of two bridging (Ph2P)2py ligands and a 2,2'-bipyridyl ligand chelating at each copper atom. Thus each copper atom has a tetrahedral geometry. Based on characterisation ...
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