Abstract The four 3H, 4H-2-difluoromethylpentafluoro-oxolans reacted with powderedpotassium hydroxide in suspension in benzene to give 3H-(1) and 4H-(2) 2- difluoromethyltetrafluoro-3, 4-oxolen, different proportions being formedfrom each stereoisomer. 3H/4H-and 4H/JH-2-Trifluoromethylpentafluoro-oxolanslikewise afforded different proportions of 3H-(3) and 4H-(4) 2-trifluoromethyltetrafluoro-3, 4-oxolen. From ...