Reaction of 2-methoxy-3H-azepine with NBS: Efficient synthesis of 2-substituted 2H-azepines

Christopher E.J. Cordonier, Kyosuke Satake, Mikihiko Atarashi, Yousuke Kawamoto, Hideki Okamoto, Masaru Kimura

Research output: Contribution to journalArticle

10 Citations (Scopus)

Abstract

(Chemical Equation Presented) The reaction of 2-methoxy-3H-azepines, in the presence or absence of a nucleophile, with N-bromosuccinimide (NBS) gave a regioselective 1,4-adduct from which the corresponding 2H-azepine derivatives were formed via base-promoted hydrogen bromide elimination, generally in moderate to quantitative yield. Competitive formation of 4-bromo-2-methoxy-3H- azepine by electrophilic substitutuion or 3H-azepin-2-yl 2H-azepin-2-yl ether by transetherification was minimized at lower reaction temperatures. Quantitative substitution of 2-(2′,4′,6′-trichlorophenoxy)-2H-azepine derivatives, formed in moderate yield from the respective 3H-azepine and NBS in the presence of 2,4,6-trichlorophenol (TCP), by various nucleophiles gave the corresponding 2-substituted 2H-azepine. Among these nucleophiles were alkanethiol and alkylamine that are not tolerated in the reaction of 3H-azepine and NBS.

Original languageEnglish
Pages (from-to)3425-3436
Number of pages12
JournalJournal of Organic Chemistry
Volume70
Issue number9
DOIs
Publication statusPublished - Apr 29 2005

ASJC Scopus subject areas

  • Organic Chemistry

Fingerprint Dive into the research topics of 'Reaction of 2-methoxy-3H-azepine with NBS: Efficient synthesis of 2-substituted 2H-azepines'. Together they form a unique fingerprint.

Cite this