SYNTHESIS AND CRYSTAL-STRUCTURE OF THE TETRAMERIC NITRIDO COMPLEX [CU(CH3CN)4]2[W4N4CL14(CH3CN)2]

The title compound has been prepared by the reaction of CuCl with WNCl3, in acetonitrile solution, forming red, moisture sensitive crystals. They were characterized by IR spectroscopy and by an X-ray structure determination. Space group I2/a, Z = 4, 2027 observed unique reflections, R = 0.049. Lattice dimensions at - 80-degrees-C: a = 2527.0, b = 971.9, c = 2137.5 pm, beta = 106.01-degrees. The compound consists of [Cu(CH3CN)4]+ ions, which are arranged to form strands, and of anions [W4N4Cl14(CH3CN)2]2-, in which the tungsten atoms were located at the vertices of a square and are linked with one another via linear W=N-W bridges. Two of the four tungsten atoms have four chlorine atoms as terminal ligands, the other two tungsten atoms have three chlorine atoms and an acetonitrile molecule as terminal ligands.