SYNTHESIS AND CHARACTERIZATION OF TAUTOMERIC TRIAZOLIUM YLIDES

In this paper, for the first time, it is announced the synthesis and c haracterization of tautomeric equilibrium in the class of cycloimmoniu m ylides. The synthesis of tautomeric triazolium ylides 10, 11 and 12 have been realized by the ''salt method'' in their 1,2,4-triazolium sa lt 7, 8 and 9 respectively, in the presence of a base (K2CO3 or TEA). Theoretically by the MINDO/3 procedure method and experimentally by th e sybthesis of disubstituted triazolium ylides 14, 15 and 16 it has be en verified that the tautomeric phenacylide forms 10b, 11a and 12a are more reactive than their carbethoxymethylide form 10a, 11b and 12b, r espectively, in reaction with picryl chloride. All structures obtained in this paper have been established using elemental analysis, mass-, ir-, H-1-NMR- and C-13-NMR-spectra.