Mechanistic study on hydrogenation of enamides
Title: |
Mechanistic study on hydrogenation of enamides |
DNr: |
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: |
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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.