Enantioselective Michael Addition of Nitroalkanes to Nitroalkenes Catalyzed by Chiral Bifunctional Quinine-Based Squaramides

KANBEROĞLU E., TANYELİ C.

ASIAN JOURNAL OF ORGANIC CHEMISTRY, vol.5, no.1, pp.114-119, 2016 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 5 Issue: 1
  • Publication Date: 2016
  • Doi Number: 10.1002/ajoc.201500339
  • Journal Name: ASIAN JOURNAL OF ORGANIC CHEMISTRY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Index Chemicus (IC)
  • Page Numbers: pp.114-119
  • Keywords: asymmetric catalysis, enantioselectivity, Michael addition, nitro compounds, organocatalysis, CONJUGATE ADDITION, ORGANOCATALYSTS
  • Middle East Technical University Affiliated: Yes

Abstract

A family of chiral bifunctional acid-/base-type quinine/squaramide organocatalysts is shown to be highly active promoters of the conjugate addition of 1-nitropropane to various trans--nitroalkenes. The cooperation of the quinine and the sterically encumbered squaramide moieties catalyzed the Michael addition reactions at 0 degrees C by using a catalyst loading of only 2mol% to afford the 1,3-dinitro Michael adducts with excellent enantioselectivity and diastereoselectivity (up to 95%ee and syn/anti isomers up to 96:4).