| dc.description | The synthesis and comprehensive characterization (NMR, FT-IR, FT-Raman, X-ray) of a series of coordination complexes in which an electron-rich (lone pair bearing) phosphorus(III) centre acts as a Lewis acceptor is presented. Previous work has shown that iminophosphines of the type Mes*NPX (Mes* = 2,4,6-tri- t-butylphenyl, X = Cl, OSO2CF3) react with a variety of ligands (e.g., imidazol-2-ylidene, amine, phosphine), which effect nucleophilic displacement of X as an anion. The resulting cations are best described as 1:1 adducts of a neutral ligand on a phosphadiazonium Lewis acceptor (Mes*NP+). This chemistry has now been extended to include complexes of the phosphadiazonium cation with both bidentate- and bidentate-chelating ligands, as well as donor-rich adducts where more than one monodentate ligand coordinates to the acceptor. In a similar fashion, dicationic, acceptor-rich phosphadiazonium complexes have been synthesized through the use of bridging ligands. The isolation and characterization of these coordination complexes has resulted in the observation of a number of novel bonding environments for phosphorus, including hypervalent phosphorus(III) species. The coordination of neutral donors to the phosphadiazonium cation represents a new synthetic methodology in phosphorus chemistry, where phosphorus-element (element = C, N, O, S, Se, P) bonds are formed through donor-acceptor interactions. | en_US |
