Synthesis of 7-aryl-2-cinnamyl-8-toxycarbonyl[1,2,4]triazolo[1,5-a]pyridine via 2-etoxycarbonylcinnamonitriles With 2‾-cinnamoyl-2-cyanoacetohydrazide

Abstract EN

A series of 7-aryl-2-cinnamyl-8-etoxycarbonyl [1, 2, 4]triazolo [1, 5-a]pyridine have been prepared by the reaction of 2-etoxycarbonylcinnamonitriles with 2‾-cinnamoyl-2-cyanoacetohydrazide.

An alternative cyclization leading to the formation of piperidinium pyrazolo [3, 4-b] pyridinides.

This compounds were isolated from the reaction mixture as the corresponding piperidinium salts due to the high stability of the heterocyclic anion.

Acidification with dilute hy- drochloric acid yielded the neutral 7-aryl-2-cinnamyl-8-etoxycarbonyl [1, 2, 4] triazolo [1, 5-a] pyridine.

Depending on the reaction conditions.