Die Kristallstrukturen der Cyclothiazenokomplexe [MoCl3(N3S2)(Pyridin)] und [MoCl3(N3S2)(Tetrahydrofuran)] / The Crystal Structures of the Cyclothiazeno-Complexes [MoCl3(N3S2)(Pyridine)] and [MoCl3(N3S2)(Tetrahydrofurane)

Abstract

An improved method of synthesis for MoCl3(N3S2) from molybdenum pentachloride and trithiazylchloride is given. Its reaction with pyridine and tetrahydrofuran in a CH2Cl2 suspension yields the donor-acceptor complexes [MoCl3(N3S2)(C5H5N)] and [MoCl3(N3S2)(C4H8O)], respectively. Both are soluble in CH2Cl2 and can be obtained in form of black, moisture sensitive crystals. Their IR spectra are reported and their crystal structures were determined by X-ray diffraction. Both compounds have nearly the same structure (monoclinic, space group P21/c, Z = 4). Lattice constants: [MoCl3(N3S2)(C5H5N)], a = 1102.2, b = 997.7, c = 1134.9 pm, α = 94.19° (1582 observed, independent reflexions, R = 0.023); [MoCl3(N3S2)(C4H8O)], a = 1069.7, b = 1002.5, c = 1122.0 pm, β = 93.77° (1440 reflexions, R = 0.024). In the molecules, the Mo atoms are members of nearly planar MoN3S2 rings with MoN bond distances between 178 and 185 pm , which correspond to double bonds. The sixfold coordination of the Mo atoms is completed by three chlorine atoms and the N or O atom of the pyridine or tetrahydrofuran ligand, respectively. The solvate molecules are in trans positions to one of the N atoms and form dihedral angles of 34.0° and 41.4° with the M oN3S2 rings, respectively.