Reactions of chromium, molybdenum and tungsten carbonyls with a tetradentate Schiff base

Interaction of metal carbonyls M(CO)(6) (M = Cr, Mo and W) with the tetradentate Schiff base bis(salicylaldehyde)phenylenediimine (salphenH(2)) was studied in THE Under reduced pressure, reaction of salphenH(2) with M(CO)(6) (M = Cr, Mo) yielded Cr(CO)(2)(salphen) 1 and MoO(CO)(salphen) 2. The complexes MoO2(salphenH)(2) 3 and W2O6(salphenH(2)) 4 were isolated from reactions in air. All the complexes were characterized by elemental analysis, mass spectrometry and IR and H-1 NMR spectroscopy. Spectroscopic studies of the reported complexes revealed the proposed structures. The UV-vis spectra of the complexes in different solvents showed bands due to either metal-to-ligand or ligand-to-metal charge transfer. Thermal properties of the chromium and molybdenum complexes were investigated by thermogravimetric techniques.