Process for preparing perfluoroalkyl iodides

Perfluoroalkyl iodides are obtained by reacting iodine, iodine pentafluoride and tetrafluoroethylene at 0-110 DEG C. in the presence of SbF5,SbF3 or anhydrous SnF2 as catalyst. When the mol. ratio I2: IF5 is at least 2: 1 and the ratio C2F4: IF5 is at least 5: 1, the product is essentially C2F5I; when the above ratios are less than 2: 1 and at least 1: 1 respectively, products of the formula C2F5 (CF2CF2)nI, where n is an integer, are obtained. The amount of catalyst used is usually 0.007-0.2 mol. per mol. of IF5. Specifications 885,007 and 930,758 are referred to.