X-ray crystal structure of azoxybenzene oxotetrachlorotungsten(VI), (C6H5N)2OWVIOCl4

The crystal and molecular structure of azoxybenzene oxotetrachlorotungsten(VI) has been determined from X-ray diffractometer data. The structure was solved by Patterson and Fourier methods and refined by least-squares techniques to R = 0.058 for 1869 independent reflections.The crystals are monoclinic, space group P2₁/c, with Z = 4, in a unit cell of dimensions: a = 8.314(3), b = 15.100(5), c = 12.901(7) Å, α = 95.31(5)°. The azoxybenzene residue, the structure of which resembles that of free trans azobenzene, is linked to the tungsten atom through its oxygen atom. The coordination at the metal (two oxygen atoms and four chlorine atoms) corresponds to a distorted octahedron.This distortion is very similar to those observed in similar tungsten compounds. There is a intramolecular C?O distance of 2.77 Å between two atoms four bonds apart, of the azoxybenzene residue.