Organocatalytic synthesis of densely functionalized oxa-bridged 2,6-epoxybenzo[: B] [1,5]oxazocine heterocycles

Ramani Gurubrahamam, Koppanathi Nagaraju, Kwunmin Chen

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Metal-free addition of salicylhydrazones to electron deficient internal alkynes catalyzed by 1,4-diazabicyclo[2.2.2]octane (DABCO) to yield oxa-bridged 2,6-epoxybenzo[b][1,5]oxazocine heterocycles was achieved. The demonstrated protocol proceeds through an o-quinone methide formation, aza-Michael addition, stereoselective protonation, enamine promoted aromatization, O,O-acetalization and O,N-aminalization sequence to provide privileged heterocycles in good yields with high diastereoselectivities.

Original languageEnglish
Pages (from-to)6048-6051
Number of pages4
JournalChemical Communications
Volume54
Issue number47
DOIs
Publication statusPublished - 2018 Jan 1

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Oxazocines
Aromatization
Alkynes
Protonation
Metals
Electrons
triethylenediamine
quinone methide

ASJC Scopus subject areas

  • Catalysis
  • Electronic, Optical and Magnetic Materials
  • Ceramics and Composites
  • Chemistry(all)
  • Surfaces, Coatings and Films
  • Metals and Alloys
  • Materials Chemistry

Cite this

Organocatalytic synthesis of densely functionalized oxa-bridged 2,6-epoxybenzo[ : B] [1,5]oxazocine heterocycles. / Gurubrahamam, Ramani; Nagaraju, Koppanathi; Chen, Kwunmin.

In: Chemical Communications, Vol. 54, No. 47, 01.01.2018, p. 6048-6051.

Research output: Contribution to journalArticle

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