Mechanistic study on hydrogenation of enamides
Title: Mechanistic study on hydrogenation of enamides
SNIC Project: SNIC 2020/13-79
Project Type: SNIC Small Compute
Principal Investigator: Yangjianping Yang <yang.jianping@su.se>
Affiliation: Stockholms universitet
Duration: 2020-09-15 – 2021-10-01
Classification: 10405
Homepage: http://www.organ.su.se/pga/pga_group.html
Keywords:

Abstract

We have developed an efficient hydrogenation of enamides catalyzed by N,P-Iridium complexes. Significantly, the hydrogenation of (E) and (Z) isomers converge to the same absolute configuration of the product. This allowed the hydrogenation of a wide range of E/Z mixtures of trisubstituted enamides with excellent enantioselectivity, up to 99% ee. Deuterium and kinetic experiments suggest multiple pathways for the observed enantioconvergence: for α-aryl enamides a fast isomerization of the double bond can take place. on the other hand for α-alkyl enamides the double bond isomerization cannot be detected, rather a substrate chelation could prevail on steric hindrance effects. We are now exploring this reaction using DFT to explain the formation of the products.