Catalytic asymmetric 1,4-additions of beta-keto esters to nitroalkenes promoted by a bifunctional homobimetallic Co2-Schiff base complex

Molecules. 2010 Jan 22;15(1):532-44. doi: 10.3390/molecules15010532.

Abstract

Catalytic asymmetric 1,4-addition of beta-keto esters to nitroalkenes is described. 2.5 mol % of a homobimetallic Lewis acid/Brønsted base bifunctional Co2-Schiff base complex smoothly promoted the reaction in excellent yield (up to 99%), diastereoselectivity, and enantioselectivity (up to >30:1 dr and 98% ee). Catalyst loading was successfully reduced to 0.1 mol %. Mechanistic studies suggested that intramolecular cooperative functions of the two Co-metal centers are important for high catalytic activity and stereoselectivity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalysis
  • Cobalt / chemistry*
  • Esters / chemistry*
  • Kinetics
  • Nitro Compounds / chemistry*
  • Schiff Bases / chemistry*

Substances

  • Esters
  • Nitro Compounds
  • Schiff Bases
  • Cobalt