Organophosphine ligands: Design and synthesis for organometallic applications

Polyorganophosphines have been synthesized for use as tethers in the formation of one dimensional conductors and multidentate organophosphines have been synthesized as a means of holding metal clusters in close proximity to enhance cluster reactivity cooperativity. Three different methods have been evaluated for the formation of three carbon spaced polyorganophosphines: ring-open polymerization, condensation polymerization and addition polymerization. The four-membered heterocycle, $\beta$-tert-butyl-1-phenylphosphetane, was synthesized by a heteroatom metallacycle transfer reaction. The product was characterized by $\rm \sp{31}P\{\sp1H\}$ and $\sp1$H NMR spectroscopy, and also by complexation to a Pt(II) center. $\beta$-tert-butyl-1-phenylphosphetane was found to be stable to ring-open polymerization. Long P-C bond lengths and the presence of gauche interactions most likely influenced the stability of the heterocycle. The condensation polymerization of alkaliphosphides with dihaloalkanes was examined. The polyorganophosphines were examined by $\rm \sp{31}P\{\sp1H\}$ NMR spectroscopy and also by Fast Atom Bombardment Mass Spectroscopy. Although oligomeric polyorganophosphines were synthesized, LiCl condensate impurity remained a problem. The step addition formation of polyorganophosphine was found to be a simple and clean procedure to forming a variety of polyorganophosphines. The starting materials are commercially available or readily synthesized and purified. Little byproduct formation was observed and the oligomerization occurs in a solventless, one-pot procedure. The polyorganophosphines produced by this method were characterized by $\rm \sp{31}P\{\sp1H\}$ NMR spectroscopy, Plasma Desorption Mass Spectroscopy and also by size exclusion chromatography. Poly(1-phenyl-1-phosphabutylene) synthesized by the step addition formation method was metallated with W(CO)$\sb5,$ and AuCl. Additionally, different inorganic monomers containing the polymerizable ligand bis(allyl)phenylphosphine were synthesized and examined for ligand centered reactivity