Thermal degradation of the transition metal carbonyl complexes - I. TG and DSC of monodentate bis-(diphenylphosphino)-methane substituted carbonyl complexes of chromium, molybdenum and tungsten

Abstract

The thermal degradation of three monosubstituted hexacarbonyl complexes, M(CO)5(dppm) (where M=Cr, Mo and W;dppm=Bis-(diphenylphosphino)-methane) has been studied using TG and DSC technics and their results reported. All the complexes facilely lose a carbonyl ligand (CO) below 200 °C. The kinetic analysis on the molybdenum complex suggested a first order dissociation pathway for this decarbonylation process. Dephosphination occurred at high temperature, followed by further decarbonylations. The enthalpy changes associated with the first decarbonylation are reported. The measured kinetic parameters are in good agreement with the literature values on similar systems obtained from solution studies. © 1987 Wiley Heyden Ltd., Chichester and Akadémiai Kiadó.