Synthesis of Spirobicyclic Pyrazoles by Intramolecular Dipolar Cycloadditions/[1s, 5s] Sigmatropic Rearrangements.

The formation of fused pyrazoles via intramolecular 1,3-dipolar cycloadditions of diazo intermediates with pendant alkynes is described. A subsequent thermal [1s, 5s] sigmatropic shift of these pyrazole systems resulted in a ring contraction, forming spirocyclic pyrazoles. The limitations of this rearrangement were explored by changing the substituents on the nonmigrating aromatic ring and by using substrates lacking an aromatic linkage to the propargyl group.

• Publication year

  2019

• Venue

  Organic Letters

• Publication date

  2019-09-05

• Fields of study

  Medicine, Chemistry

• Identifiers
  DOI 10.1021/acs.orglett.9b02124PMID 31486651PMCID PMC6955098
• 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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