CYCLOCONDENSATION OF 2-PHENACYL-1H-BENZIMIDAZOLE WITH ACYLHYDRAZINES: SYNTHESIS AND TAUTOMERISM OF 2-(PYRAZOL-4-YL)-1H-BENZIMIDAZOLES
DOI:
https://doi.org/10.1007/1071Abstract
The previously unknown 2-(pyrazol-4-yl)benzimidazoles containing aryl groups in the pyrazolyl ring have been obtained by the reaction of 2-phenacyl-1H-benzimidazole with aroylhydrazines. The compounds with nitrophenyl and pyridyl substituents in the pyrazole ring show pyrazolyl tautomerism with differences in the 1H NMR spectra. A semi-empirical method is proposed to determine the tautomeric composition of the synthesized pyrazoles.
Authors: I. B. Dzvinchuk, A. V. Vypirailenko, V. V. Pirozhenko, and M. O. Lozinsky.
English Translation in Chemistry of Heterocyclic Compounds, 1999, 35 (11), pp 1319-1324