Molybdenum and Tungsten Carbonyl Complexes With N2 Schiff Base Donors: Syntheses, Spectral, Electrochemical, Thermal, Catalytic Epoxidation, and Biological Activity Studies

Abstract

Thermal reactions of Mo(CO)6 with the Schiff base 4-nitro-N-(pyridine-2-yl-methylene)aniline (NPMA) in THF in absence and presence of triphenyl phosphine (PPh3), pyridine (py) or thiourea (Tu) gave the four carbonyl complexes, [Mo(CO)4(NPMA)] (1), [Mo(CO)3(NPMA)(PPh3)] (2) [Mo2(O)2(CO)2(NPMA)2(Py)2] (3), and [Mo2(O)2(CO)4(NPMA)(Tu)2] (4), respectively. Thermal reaction of W(CO)6 with NPMA in THF gave the two complexes [W2(O)6(NPMA)] (5) and [W2(O)6(NPMA)(Py)2] (6) in absence and presence of pyridine, respectively, while under sunlight irradiation the complex [W2(CO)6(NPMA)2] (7) was isolated. Magnetic susceptibility, elemental analyses, and IR, mass, and 1H NMR spectroscopy were studied. Thermal, cyclic voltammetry, catalytic epoxidation, and biological activity were also investigated.