Valence Bond Isomerization of Fused [1, 2, 3] Triazolium Salts with Bridgehead Nitrogen Atom. Fused Azolium Salts. 19

…, Z Riedl, T Soós, G Timári, A Messmer

Index: Beres, Mariann; Hajos, Gyoergy; Riedl, Zsuzsanna; Timari, Geza; Messmer, Andras Monatshefte fur Chemie, 1998 , vol. 129, # 8-9 p. 897 - 908

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Citation Number: 14

Abstract

[1, 2, 3] Triazolo [1, 5-a] quinolinium (7),[1, 2, 3] triazolo [1, 5-b] isoquinolinium (8), and [1, 2, 3] triazolo [1, 5-a] pyrazinium salts (9) when heated in trifluoroacetic acid and/or 1, 2- dichlorobenzene undergo valence bond isomerization to ring-opened reactive intermediates (eg, 8 gave 13) which can participate in (i) electrophilic substitution as nitrenium cations to yield pyrazole-and indazole-fused new heterocycles (eg, from 13, 14, and 15 are formed),( ...