N‑Heterocyclic Olefins of Pyrazole and Indazole

Deprotonation of 3-methylpyrazolium and 3-methylindazolium salts yielded N-heterocyclic olefins (NHOs) in excellent yields, which reacted with isocyanates, halogens, and carbon disulfide. Calculated proton affinities are 261 kcal/mol (indazole NHOs) and 272 kcal/mol (pyrazole NHOs). The calculated pK a values are between 14.8 and 25.2, and bond lengths of the exocyclic double bond are slightly shorter than those of imidazole NHOs. As expected, the highest occupied molecular orbitals show significant atomic orbital coefficients at the exocyclic carbon atom.

• Publication year

  2025

• Venue

  Organic Letters

• Publication date

  2025-05-28

• Fields of study

  Medicine, Chemistry

• Identifiers
  DOI 10.1021/acs.orglett.5c00775PMID 40435496PMCID 12150313
• External record

  Open on Semantic Scholar

• Source metadata

  Semantic Scholar, PubMed

• No claims are published for this paper.

• No concepts are published for this paper.

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