Reaction of dimethylzinc with tantalum(V) chloride and some co-ordination compounds of methyltantalum(V) chloride, dimethyltantalum(V) chloride and methylniobium(V) chloride

Abstract

It has been shown that the reaction between dimethylzincand tantalum(V) chloride involves equilibria in which zinc chloride takes part. MeTaCl₄ and Me₂TaCl₃ were present in the reaction mixtures and it was possible to prepare and characterise a series of their complexes with a variety of monodentate and bidentate ligands. Some further complexes of MeNbCl₄ have been prepared. The stoicheiometry of the complexes fall into the categories MeNbCl₄,L, MeTaCl₄,L, Me₂TaCl₃,L, 2MeNbCl₄,L, 2MeTaCl₄,L, and 2Me₂TaCl₃,L, apart from 4MeTaCl₄,3diox. Proposed structures based on i.r. and n.m.r. spectra involve six-co-ordinated metal atoms in most instances, although seven-co-ordination seems probable with complexes formed by some bidentate ligands.