Oxovanadium(V) complexes of salicylaldehyde and 3-methoxysalicylaldehyde 4-phenylthiosemicarbazones. formation of two new thiazoline compounds

In the reaction of tris(2, 4-pentandionato)vanadium(III) with salicylaldehyde 4-phenylthiosemicarbazone (in complex 1) and 3-methoxy-salicylaldehyde 4-phenylthiosemicarbazone (in complex 3), two new mononuclear complexes of vanadium(V), [VO(SNO)(OCH3)] (1, 3) and thiazoline derivatives, {; ; ; ; ; ; R-CHNN[CNC(C6H5)C(CH3)C(O)(CH3)S]}; ; ; ; ; ; [R = -C6H4(OH) (L1cycl, 2) or -C6H3(OCH3)(OH) (L2cycl, 4)] have been prepared. The isolation of the thiazoline derivatives is the first example of cyclization reactions of thiosemicarbazones with an appropriate β -diketone involving vanadium. In vanadium(V) complexes, 1 and 3 vanadium is coordinated by one doubly bonded oxygen atom, ONS atoms from the salicylaldehyde thiosemicarbazone ligand and by an oxygen atom from methoxo ligand. All compounds have been characterized by means of chemical analyses and IR spectroscopy. The crystal and molecular structures of 1-4 have been determined by single-crystal X-ray diffraction method.