Reaction of niobium(V) chloride with dimethylzinc and some Co-ordination compounds of mono- and di-methylnibium(V) chloride

Abstract

The reaction between niobium(V) chloride and dimethylzinc has been shown to involve equilibria with zinc chloride and both the mono- and di-methylniobium(V) chlorides. MeNbCl4 has not been isolated but its complexes with 1,2-diphenylthioethane and 1,4-dioxan have been prepared. Me2NbCl3 has been isolated and a series of complexes formed with a range of monodentate and bidentate ligands containing nitrogen, phosphorus, oxygen, and sulphur donor atoms; these complexes have been characterised through measurements of i.r. and n.m.r. spectra. Monodentate donors (L) yield six-co-ordinate complexes (Me2NbCl3,L) in which the methyl groups are trans. Bidentate ligands (B) give complexes in which the niobium may be seven-co-ordinate (Me2NbCl3,B) or six-co-ordinate (2Me2NbCl3,B) with the ligand linking two niobium atoms.