Preparation and Structure of Tetraphenylarsonium Bis[1,2-Dicyanoethenedithiolato]oxotechnetate(V)

Abstract

The reaction of sodium 1,2-dicyanoethenedithiolate with [AsPh₄][TcOCl₄] in ethanol yields crystals of [AsPh₄][ TcO ( mnt )₂] (1). Crystals of (1) are monoclinic and belong to the space group P2₁/c with a 12.636(1), b 13.749(1), c 18.484(1)Ǻ, β 93.49(1)° with Z 4. Refinement on 3669 data measured with Cu Kα radiation converged at R 0.063. The structure consists of [ TcO ( mnt )₂]^- anions and [AsPh₄]⁺ cations. The technetium(V) atom is five-coordinate with the four sulfur atoms in the basal positions and the oxo ligand in the apical position, to give a distorted square-pyramidal environment about the technetium. The Tc =O bond distance is 1.655(6)Ǻ.