A study of the reaction of halocarbonyls, [M(CO)4X2L2,(M=Mo,W;X=CL,Br) with monocyclic secondary and tertiary alkylamines

Abstract

The molybdenum and tungsten halocarbonyls [M(CO)4X2]2 (M=MO, W; X=C1, Br) react with a large excess of I-methylpyrrolidine, I-methylpiperidine, 1-ethylpiperidne, 2-ethylpiperidine and piperidine to give amine-substituted complexes of the type M(CO)4L2 or M(CO)3L3, aminium salts and dimerized enamines. As there was no evidence for any molybdenum(III) or tungsten(III) species, the reaction is interpreted as taking place via a redox mechanism. Piperazine reacted with these halocarbonyls to form substituted halocarbonyls of the type M(CO)3D2X2, (D=piperazine). In the case of molybdenum complexes, the same products were obtained even when the reaction mixture was refluxed in boiling n-propanol which boils at 97.10C. The reaction products were characterized by Elemental analysis, IR., UV and 1H NMR spectroscopy.