UNSATURATED NITROGEN-COMPOUNDS CONTAINING FLUORINE .8. THE REACTION OF 2,5-DICHLORO-1,1,1,6,6,6-HEXAFLUORO-3,4-DIAZAHEXA-2,4-DIENE WITH TRIETHYLAMINE AND RELATED REACTIONS

Exposure of a mixture of the title azine (1) and triethylamine (1:2 molar ratio) to daylight gives as major products, triethylamine hydrochloride and the DELTA-2-azetine CF3 activated C = CH-CH(NEt2)-N-N = CClCF3 (3), together with trifluoroacetonitrile and tar; a single electron transfer (SET) mechanism is proposed involving the intermediacy of the enamine Et2NCH = CH2. In contrast the reaction of azine (1) with tri-n-propylamine in light affords the amine hydrochloride, the substituted azine CF3CCl = N-N = C(NPr(n)2)CF3 (14) and tar. Treatment of the heterocycle (3) with diethylamine results in replacement of CI by NEt2 to give the azetine (6) which is also formed when the azine CF3CCl = N-N = C(NEt2)CF3 (7) is heated with triethylamine.