Solvent-Free Solid State Dechlorination of C60Cl6 and C60Cl12 with Cesium Iodide

The complete dechlorination of C60Cl6 or C60Cl12 to C-60 was achieved smoothly and at ambient temperature in a compressed pellet of cesium iodide (CsI). The progress of the dechlorination reaction was followed by FT-IR spectroscopy. The pseudofirst order kinetic rate constants of dechlorination of both compounds were determined from the nu(C-Cl) bands leading to the following values: k = 7.26 x 10(-5) s(-1) for C60Cl12 and k' = 6.61 x 10(-5) s(-1) for C60Cl6. Furthermore, both C60Cl6 and C60Cl12 were studied with thermogravimetric and derivative analysis (TGA-DTG) to confirm their composition and their thermal stability. Only for C60Cl12, the activation energy for the thermal decomposition was determined at 163 kJ/mol with differential scanning calorimetry (DSC) and the decomposition enthalpy was determined at 381.5 +/- 55 kJ/mol. From the latter value, the enthalpy of formation of C60Cl12 was estimated at 1498 +/- 136 kJ/mol.