Thermal degradation of transition metal carbonyl complexes. Part IV: Thermogravimetric studies of various stoichiometric mixtures of trimethylamine N-oxide dihydrate and hexacarbonyl molybdenum

Abstract

The effect of (CH3)3NO·2H2O on the thermal degradation of Mo(CO)6 in nitrogen was studied by thermogravimetry (TG) and derivative thermogravimetry (DTG). Pure Mo(CO)6 and (CH3)3NO readily sublime without decomposition. On mixing and heating, oxidative decarbonylation readily occurs, followed by substitution. This yields Mo(CO)6-n[(CH3)3N]n and CO2. The substituted carbonyl complexes undergo further ligand cleavage and disintegrate into metal residue. In a stoichiometric ratio of greater than 3:1 for (CH3)3NO· 2H2O:Mo(CO)6, free and excess amine oxide are detected in the TG profile, which lends strong support to the formation of the tricarbonyl Mo(CO)3[(CH3)3N]3, but not the higher substituted analogues. © 1989.