Structure of a 4-nitroso-5-aminopyrazole and its salts: Tautomerism, protonation, and E/Z isomerism

M H Holschbach, D Sanz, R M Claramunt, L Infantes, S Motherwell, P R Raithby, M L Jimeno, D Herrero, L Alkorta, N Jagerovic, J Elguero

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

The structures of 1-benzyl-4-nitroso-5-aminopyrazole (1) and its hydrochloride (1H(+)) have been determined in the solid state and in solution in DMSO, methanol, and ethanol. The free base exists in solution as a mixture of amino/nitroso tautomers 2a and 2b rather than in the imino/oxime tautomers 3. The conjugated cation 1H(+) results from the protonation of the nitroso group. X-ray crystallography showed that both amino hydrogen atoms of 2a form NH...O=N hydrogen bonds: one is intramolecular, the other links adjacent molecules in an infinite chain.
Original languageEnglish
Pages (from-to)8831-8837
Number of pages7
JournalJournal of Organic Chemistry
Volume68
Issue number23
DOIs
Publication statusPublished - 2003

Fingerprint Dive into the research topics of 'Structure of a 4-nitroso-5-aminopyrazole and its salts: Tautomerism, protonation, and E/Z isomerism'. Together they form a unique fingerprint.

  • Cite this

    Holschbach, M. H., Sanz, D., Claramunt, R. M., Infantes, L., Motherwell, S., Raithby, P. R., Jimeno, M. L., Herrero, D., Alkorta, L., Jagerovic, N., & Elguero, J. (2003). Structure of a 4-nitroso-5-aminopyrazole and its salts: Tautomerism, protonation, and E/Z isomerism. Journal of Organic Chemistry, 68(23), 8831-8837. https://doi.org/10.1021/jo034833u