A facile one-pot synthesis of 2-(prop-2-yn-1-ylidene)-2,3-dihydro-1,4-thiazepines


YILMAZ E. S. , ZORA M.

SYNTHETIC COMMUNICATIONS, vol.51, no.5, pp.709-719, 2021 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 51 Issue: 5
  • Publication Date: 2021
  • Doi Number: 10.1080/00397911.2020.1850795
  • Title of Journal : SYNTHETIC COMMUNICATIONS
  • Page Numbers: pp.709-719

Abstract

An unprecedented method for the synthesis of 2-(prop-2-yn-1-ylidene)-2,3-dihydro-1,4-thiazepines from N-(2,4-pentadiynyl) beta-enaminones is reported. Upon treatment with Lawesson's reagent, N-(2,4-pentadiynyl) beta-enaminones were thionated to furnish N-(2,4-pentadiynyl) beta-enaminothiones, which immediately underwent 7-exo-dig cyclization to generate 2-(prop-2-yn-1-ylidene)-2,3-dihydro-1,4-thiazepines in one-pot. A general trend was observed for various N-(2,4-pentadiynyl) beta-enaminones and cyclization proceeded with broad functional group tolerance. This operationally easy method may provide quick access to a library of functionalized 1,4-thiazepines in the field of pharmaceutical chemistry.