drop by drop after the addition the mixture was brought to room temperature for about six hours and then poured into about 100 ml of ice water the organic layer was washed with an about 5 sodium hydroxide solution the crude mixture was flash chromatographed with hexane providing an about 60 yield of u03b1 u03b1 u03b1 u2032 u03b1 u2032 tetrafluoro 2 3 5 6 tetrafluoroxylene the 1 h nmr resonance of the u03b1 u03b1 u03b1 u2032 u03b1 u2032 tetrafluoro 2 3 5 6 tetrafluoroxylene product in cdcl 3 was u03b4 6 952 t 2h and the 19 f nmr resonance was u03b4 u2212 115 19 4f d j 50 hz u2212 115 282 2f d u2212 142 17 s 4f the melting point of the product was about 70 u00b0 c about 26 g about 0 104 mol of u03b1 u03b1 u03b1 u2032 u03b1 u2032 tetrafluoro 2 3 5 6 tetrafluoroxylene was dissolved in about 400 ml of carbon tetrachloride chlorine gas was bubbled through the mixture for about 56 hours at 60 u00b0 c the reaction was monitored by checking the 19 f nmr resonance the residue was distilled under vacuum at about 0 2 mm hg and about 3 u00b0 c to yield u03b1 u03b1 u2032 dichloro u03b1 u03b1 u03b1 u2032 u03b1 u2032 tetrafluoro 2 3 5 6 tetrafluoroxylene product which was found to have a 19 f nmr resonance in cdcl 3 of u03b4 u2212 47 61 m 4f u2212 137 88 m 4f the product was further analyzed by gc ei ms to be c 8.