Bifunctional squaramide catalyzed stereoselective Mannich reaction of alpha-azido ketones with isatin-derived ketimines


KARAHAN S. , TANYELİ C.

ORGANIC & BIOMOLECULAR CHEMISTRY, vol.18, no.3, pp.479-487, 2020 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 18 Issue: 3
  • Publication Date: 2020
  • Doi Number: 10.1039/c9ob02208b
  • Title of Journal : ORGANIC & BIOMOLECULAR CHEMISTRY
  • Page Numbers: pp.479-487

Abstract

Asymmetric organocatalytic Mannich reaction of alpha-azido ketones and N-Boc protected isatin-derived ketimines were investigated for the first time. Examination of both 2-adamantyl and 3,5-bis(trifluoromethyl)aniline substituted quinine-based squaramides afforded chiral Mannich bases with two contiguous stereogenic centers in high yields (up to 97%) and stereoselectivity (up to dr = 24 : 1 syn : anti and 96% ee). Azido and masked amino functionalities of the potent heterocycle precursor adducts were utilized in representative examples.