A process for preparing fluoro-olefins

A process for synthesizing an olefinic composition represented by the formula: CF2=CF(CF2CF2)nSO2F where n = 1 to 5 comprising (a) contacting CF2ClCFCl(CF2CF2)nI, wherein n = 1 to 5, with Na2S2O4 and NaHCO3 in a mixture of water and an aprotic polar solvent at a temperature in the range of room temperature to 110 DEG C, to form CF2ClCFCl(CF2CF2)nSO2Na; (b) contacting the said CF2ClCFCl(CF2CF2)nSO2Na with Cl2 in water or a mixture of water and an aprotic polar solvent at a temperature in the range of 0-200 DEG C to form CF2ClCFCl(CF2CF2)nSO2Cl; (c) contacting the said CF2ClCFCl(CF2CF2)nSO2Cl with a univalent metal fluoride in an anhydrous aprotic polar solvent to form CF2ClCFCl(CF2CF2)nSO2F; (d) contacting said CF2ClCFCl(CF2CF2)nSO2F with Zn in an alcohol or mixture of acetic acid and alcohol to form CF2=CF(CF2CF2)nSO2F; and, (e) separating the product.