FLUORINATED ACETYLENES .3. SOME REACTIONS OF 3,3,3-TRIFLUORO-NN-BISTRIFLUOROMETHYLPROP-1-YNYLAMINE AND PERFLUORO-1,2-BISDIMETHYLAMINOACETYLENE

3,3,3-Trifluoro-NN-bistrifluoromethylprop-1-ynylamine reacts with bromine or hydrogen bromide under photochemical conditions to give the corresponding trans-addition product in high yield. Hydrogen bromide reacts with the acetylene in the dark in the presence of aluminium bromide to give the same trans-addition product and another 1:1 adduct, probably 1-bromo-3,3,3-trifluoro- NN-bistrifluoromethylprop-1-enylamine, present in the ratio 93:7. The acetylene undergoes hydrogenation and acid-catalysed hydration to yield cis-3,3,3-trifluoro-NN-bistrifluoromethylprop-1-enylamine and 3,3,3-trifluoro-NN-bistrifluoromethylpropionamide respectively, and the reaction of sodium methoxide in methanol yields a mixture of trans-3,3,3-trifluoro-1- methoxy-NN-bistrifluoromethylprop-1-enylamine and cis- or trans-3,3,3-trifluoro- 2-methoxy-NN-bistrifluoromethylprop-1-enylamine in the ratio 96:4. Perfluoro-1,2-bisdimethylaminoacetylene reacts with bromine in the dark or under photolytic conditions to give 1,2-di(bistrifluoromethylamino)-1,2- dibromoethylene (probably trans). The photochemical reaction with hydrogen bromide gives 1,2-di(bistrifluoromethylamino)-1-bromoethylene and hydrogenation yields cis-1.2-di(bistrifluoromethylamino)ethylene. Attempted acid-catalysed hydration, reaction with methanol under neutral or acid-catalysed conditions, and reaction with sodium methoxide in methanol were unsuccessful. N-Bromobistrifluoromethylamine reacts with 3,3,3-trifluoropropyne to give four 1:1 adducts of which cis- and trans-2-bromo-3,3,3-trifluoro-NN- bistrifluoromethylprop-1-enylamine are the major products.