trifluoroethyl difluoromethyl ether and chlorine gas was slowly bubbled therethrough at 10 u00b0 during which the reaction vessel was irradiated with a 250 watt incandescent light the introduction of chlorine was continued until analysis showed no starting material remaining in the reaction vessel 10 hours the reaction mixture was analyzed at 60 minute intervals by gas chromatography gc utilizing a hewlett packard model 5790a analyzer the crude reaction mixture weighed 264 g at the conclusion of chlorination and was comprised of in area percents 1 4 of cf 3 ch 2 o cf 2 cl 35 5 of isoflurane 56 0 of cf 3 ccl 2 o cf 2 h and 6 4 of cf 3 chcl o cf 2 cl this experiment was carried out in a one liter pyrex 3 neck flask equipped with a magnetic stirrer a gas introduction tube and a dry ice condenser connected to a trap 78 u00b0 three hundred grams of isopropanol was introduced into the reaction flask and 100 g of the crude mixture formed in example 1 was added thereto without purification the reaction mixture was irradiated for 1 hour at 10 cm distance at room temperature with a 450 watt medium pressure.