ChemInform Abstract: Synthesis, Structure, and Electronic Properties of Tris(propane-1,3-dithiolato) and Tris(ethylene-1,2-dithiolato) Complexes of Niobium(V) and Tantalum(V).

ChemInform Abstract

The title complexes (IIIa)-(IIIe) are prepared as shown for the example (IIIa) and characterized by spectroscopic (IR, Raman, UV/VIS, ¹H NMR) studies and for (IIIa) by X-ray structure analysis (space group Pn, Z=2). Analysis of the IR and Raman spectra of these species as well as of the analogous ethanedithiolate complexes (IIIf) reveals that the degree of trigonal twist of the MS₆ polyhedron varies in a complicated fashion depending on minute perturbation of crystal-packing forces and electronic factors. Of them the ethylenedithiolate complexes (IIId) and (IIIe) have a geometry closest to the trigonal-prismatic limit. Electronic properties of the dithiolate complexes are examined in terms of cyclic voltammetry results and electronic spectra and extended Hueckel calculations.