Thermal stability and kinetic studies of new cobalt(III) complexes with a tetraazamacrocyclic and dithiocarbamate ligands

Abstract

The thermal properties of four cobalt(III) complexes with cyclam (1,4,8,11-tetraazacyclotetradecane) and the heterocyclic dithiocarbamates Rdtc-[2-, 3-, 4-methylpiperidine (2-, 3-, 4-Mepipdtc-) or 4-thiomorpholine (Timdtc-) dithiocarbamates], of the general formula [Co(Rdtc)cyclam](ClO4)2, have been investigated by thermogravimetry (TG) and differential scanning calorimetry (DSC). The thermal decomposition pathways of these complexes were also proposed. The following thermal stability order can be recognized for the examined complexes, depending on the position of the methyl group on the piperidine ring coordinating dithiocarbamates: 2- >3- >4-Mepipdtc-. Generally, the same order was found to affect the decrease in kinetic and activation parameters.