Preparation and Structure of Dibromobis(N,N-diethyldithiocarbamato)-thionitrosyltechnetium(III)

Abstract

The title compound, [Tc (NS)(S₂CNEt₂)₂Br₂], has been prepared by the reaction of [ TcN (S₂CNEt₂)₂] with SOBr₂, and its crystal structure has been determined by single-crystal X-ray diffraction methods at 23±1°C. Crystals are orthorhombic, space group Pnma , with a 14.864(7), b 15.857(7), c 8.938(4)Ǻ, and Z 4. Full-matrix least-squares refinement gave a final R value of 0.047 for 1685 independent reflections. The technetium atom is seven-coordinate with a distorted pentagonal- bipyramidal coordination geometry. The thionitrosyl ligand and a bromo ligand occupy the axial positions, with the thionitrosyl group exerting a small trans influence with Tc-Br_trans 2.595(1) and Tc-Br_cis 2.564(1)Ǻ. The coordination of the thionitrosyl group is essentially linear with Tc -N=S 177.2(7)°, Tc -N 1.754(9), and N=S 1.504(9)Ǻ.