UNSATURATED NITROGEN-COMPOUNDS CONTAINING FLUORINE .14. A REINVESTIGATION OF THE REACTION OF 2,5-DICHLORO-1,1,1,6,6,6-HEXAFLUORO-3,4-DIAZAHEXA-2,4-DIENE WITH TRIETHYLAMINE AND SOME RELATED REACTIONS

The reaction of triethylamine with the title azine 1 (2:1 molar ratio) in light gives, as the major product, an orange liquid considered previously to be the DELTA2-azetine CF3CCl=N-N-C(CF3)=CHCHNEt2 (3), but now shown to be the open-chain isomer, i.e. the triazadecatriene CF3CCl=NN=C(CF3)CH=CHNEt3 (4) by a comparison of its H-1, C-13 and F-19 NMR spectra with those of its solid amino derivative CF3C(NH2)=NN=C(CF3)CH=CHNEt2 (6) (made in 96% yield by reaction of compound 4 with ammonia) the structure of which has been established by X-ray crystallography. A second reaction using a large excess of triethylamine (6:1 molar ratio in light followed by heating at 115-degrees-C) affords compound 4 (17%), its diethylamino derivative CF3C(NEt2)=NN=C(CF3)CH=CHNEt2 (8) (12%), the tetra-azatetradecatetraene Et2NCH=CHC(CF3)=NN=C(CF3)CH=CHNEt2 (9) (6%) and the hydrolysis product of compound 9, the dienol N=C(CF3)CH2CHNC(CF3)=CHCH(OH)O (10) (2%). Treatment of compound 9 with silica gel gives the dienol 10 (84%). The reaction of the triazadecatriene 4 with 1-diethylaminocyclopentene (5) (1:2 molar ratio) affords the 2-substituted enamine CH2(CH2)2C(NEt2)=C-C(CF3)=NN=C(CF3)CH=CHNEt2 (17) (74%) and this on hydrolysis (silica gel) gives the corresponding 2-substituted ketone O=(CH2)3CHC(CF3)=NN=C(CF3)CH=CHNEt2 (18) (75%) and the pyrazole derivative O=(CH2)3=C(CF3)NN=C(CF3)CH=CH (19) (15%).