Structural study of molybdenum(VI) complexes containing bidentate ligands: Synthesis, characterization and DFT calculations

A series of molybdenum(VI) complexes containing bidentate ligands: toluene-3,4-dithiol (1), 2-mercaptophenol (2), 2-aminothiophenol (3), ethane-1,2-dithiol (4), dithiooxamide (5) and 2-thiopheno-carboxamide (6) are reported. The hexacoordinated molybdenum tris-chelates compounds: tris-(toluene-3, 4-dithiolate)molybdenum(VI) (7), tris-(2-mercaptophenolate)molybdenum(VI) (8), tris-(2-aminothiophenolate)molybdenum(VI) (9), tris-(ethane-1,2-dithiolate)molybdenum(VI) (10). and the bis-chelates, which also contain coordinated oxo ligands: bis-(dithiooxamidate)dioxomolybdenum(VI) (11) and bis(2-thiopheno-carboxamide)dioxomolybdenum(VI) (12), were characterized by H-1 and C-13 NMR and IR spectroscopies, as well as elemental analyses and mass spectrometry. The structures of minimum energy of the coordination compounds were calculated using OFT (B3LYP/def2-TZVPP). Solid state structures of analogous compounds, as well as calculations indicated that the minimum energy structures correspond to those of trigonal prismatic geometry. (C) 2012 Elsevier Ltd. All rights reserved.