نبذة مختصرة : The simultaneous presence of an ethoxycarbonyl group on the nitrogen atom and of a C-trichloromethyl group in the N-ethoxycarbonyl-N-(2,2,2-trichloroethylidene)amine, confers some particular properties to the double bond C=N which were highlighted during this work. The cycloaddition reactions of diarylnitrilimines allow to access with good yields to some 1,3-diphenyl-5-trichloromethyl-4-ethoxycarbonyl-∆2-1,2,4-triazoline derivatives. These compounds can be easily transformed in 1,3-diaryl-1,2,4-triazoles. The reactions of arylnitriloxyde precursors present a competition between the 1,3-dipolar cycloaddition leading to 3-phenyl-5-trichloromethyl-4-ethylcarboxylate-∆2-1,2,4-oxadiazoline derivatives, and a nucleophile addition yielding ethyl 1-O-(-chlorobenzaldoximino)-2,2,2-trichloro-ethylcarbamate derivatives. By the way of nucleophile addition, the reaction of ethyldiazoacetate leads to a new diazocompound which then revealed an 1,3-dipolar reactivity towards the acetylenic esters and maleimides. In the case of acetylenic esters , the cycloaddition reaction is accompagnied by an evolution leading to very substituted pyrazoles due to [1,5] sigmatropic transposition. With the maleimides, a diastereospecific cycloaddition reaction is observed which has been rationalized by an endo-anti approach mode of reactants. The diphenyldiazomethane gives a new 2-azabuta-1,3-diene with a good yield. A mechanism has been proposed: it requires thermic opening of an aziridine leading to an azomethine ylure which is stabilized through an elimination of ethylchloroformiate giving a strongly conjugated azadiene. The presence of ester groups and chlorine atoms on the imine seems to play an important role to enable this evolution. ; La presence simultanee sur le substrat n-ethoxycarbonyl-n-(2,2,2-trichloroethylidene)amine des groupes carboxylate d'ethyle sur l'atome d'azote et trichloromethyle sur l'atome de carbone confere au motif iminique des proprietes particulieres qui ont ete mises en evidence au cours de ce travail. Les ...
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