Reflection-absorption infrared spectroscopy determined the coexistence of surface-bound trifluoromethyl (CF3) and difluorocarbene (CF2) moieties, resulting from C-I and subsequent C-F bond scission reactions below 160 K after the CF3I adsorption on Cu(111). Upon further heating, concomitant with the depletion of Cu-CF3 and Cu=CF2, a new surface intermediate was identified unequivocally as the pentafluoroethyl (CuCF2CF3) groups. This observation provides evidence for the reaction of CF2 migratory insertion into the carbon-copper bond. At about 300 K, together with the CF2 coupling pathway, the Cu-CF2CF3 species undergo a beta-fluoride elimination reaction to liberate tetrafluroethylene (CF2=CF2) into the gas-phase as the final product.