Asymmetric aldol addition of alpha-azido ketones to ethyl pyruvate mediated by a cinchona-based bifunctional urea catalyst

Okumus S., TANYELİ C., DEMİR A. G.

TETRAHEDRON LETTERS, vol.55, no.31, pp.4302-4305, 2014 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 55 Issue: 31
  • Publication Date: 2014
  • Doi Number: 10.1016/j.tetlet.2014.06.018
  • Journal Name: TETRAHEDRON LETTERS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.4302-4305
  • Middle East Technical University Affiliated: Yes

Abstract

The first asymmetric synthesis of ethyl 4-aryl-3-azido-2-hydroxy-2-methyl-4-oxobutanoates via a cinchona organocatalyst induced aldol addition of alpha-azido ketones to ethyl pyruvate has been developed. The coupling reaction under optimized conditions was carried out to furnish tetrafunctionalized synthons with enantioselectivities of up to 91:9 and enriched diastereoselectivities of up to 95:5 (syn:anti). (C) 2014 Elsevier Ltd. All rights reserved.