Complexes of Dioxomolybdenum(VI) with Acylhydrazones. Crystal Structures of Nicotinoylhydrazone 5-Nitrosalicylic Aldehyde (H2L) and Solvate Complex МоО2(L)·Me2SO

Nicotinoylhydrazone 5-nitrosalicylic aldehyde (H2L) and solvate complex МоО2(L)⋅Me2SO (I) have been synthesized and their structures have been studied by IR spectroscopy and X-ray diffraction. According to X-ray diffraction data, the molybdenum atom in I has an octahedral coordination built of two cis-O2(oxo) ligands, N(L),O(Solv) atoms in trans-positions to O(oxo) and two O(L) atoms in cis-positions to O(oxo) and in trans-positions to each other. The Mo atom coordinates ligand L2– in the tridentate (2O, N) bis-chelate manner. Average bond lengths in I are: Mo–O(oxo) 1.690 Å, Mo–N(L) 2.249 Å, Mo–O(L) 1.965 Å, Mo–O(Me2SO) 2.260 Å, the O(oxo)MoO(oxo) bond angle is 105.1°. Changes in the geometric parameters of ligand L2– when passing from H2L and coordination by the Mo atom in complex I are considered. Adduct МоО2Сl2⋅2H2L (II) has been obtained, and its structure is discussed based on IR spectroscopy data.