Oxidation reactions, coordination chemistry and antibacterial activities with ligand 2-{(diphenylphosphino)methyl}-N,N-dimethylaniline

Abstract N,N-dimethyl-o-toluidine was treated with n-butyllithium-tmeda in diethylether/hexane solution to give (2-(dimethylamino)benzyl)lithium which reacts with chlorodiphenylphosphine to form the corresponding hemilabile N,P-ligand 2-PPh2CH2-1-NMe2C6H4 (1). Oxidation of 1 with elemental sulfur or gray selenium gave the corresponding sulfide and selenide 2-(E)PPh2CH2-1-NMe2C6H4 (E = S (2), Se (3)), respectively. The reaction of 1 with M(CO)6 (M = Mo, W) afforded cis-[Mo(CO)4{2-PPh2CH2-1-NMe2C6H4 }2](4) and trans-[W(CO)4{2-PPh2CH2-1-NMe2C6H4 }2](5), respectively. The treatment of 1 with copper(I) iodide in 1:1 mol ratio produced [CuI{2-PPh2CH2-1-NMe2C6H4 }]2 (6). The complexes 4–6 have been screened for antibacterial activity and the results were compared with the activity of the free ligand 1 against four bacterial strains. Complexes 4 and 6 had the highest antibacterial activity and can be considered as promising antimicrobial agents. Compounds 1–6 were characterized by multinuclear NMR spectroscopy (1H, 13C, 31P, 77Se NMR), IR and elemental analysis. Crystal structure determinations of 1, 2, 4, and 6 were carried out.