The crystal and molecular
structures of the aryldiazenato complexes of molybdenum, [Mo(N2C6H5)(S2CNMe2)3],CH2Cl2
(1), and the m-nitro derivative [Mo{N2C6H4(m-NO2)}-(S2CNMe2)3]2,�CH2Cl2,�H2O
(2), have been determined by single-crystal X-ray diffraction methods at 294 K.
Crystals of (1) are monoclinic, P21/n, a 13.056(1), b 13.366(1), c
15.350(1) Ǻ, β 93.80(1)°, Z 4. Crystals of (2) are monoclinic, C2/c,
a 32.442(8), b 17.670(4), c 17.867(3) Ǻ, β 99.03(1)°, Z 8. Automatic
diffractometry has provided significant Bragg intensities for 2849 (1) and 3898
(2) independent reflections and the structures have been refined by
least-squares methods to R 0.036 (1) and 0.053 (2). The two unique molybdenum
complexes in (2) are essentially chemically equivalent. The complexes in (1)
and (2) possess the expected seven-coordinate pentagonal bipyramidal structures
with the aryldiazenato ligands, singly bent, occupying axial positions. The
N=N-Mo units are linear, and the bonding can be represented by N=N→Mo with the aryldiazenato ligands three-electron
donors. The m-nitro substituent in (2) interacts with a dithiocarbamate
(dtc) nitrogen atom, thereby affecting the redox
behaviour of this compound. The possible significance of this O(nitro)...N(dtc) interaction to the mechanism, whereby included
nitrobenzene solvent in the crystal lattice lowers the magnetic moments of
ferric dithiocarbamates, is discussed.
