Enantioselective synthesis of α-aryl-β2-amino-esters by cooperative isothiourea and Brønsted acid catalysis
Abstract
The synthesis of α‐aryl‐β2 ‐amino esters through enantioselective aminomethylation of an arylacetic acid ester in high yields and enantioselectivity via cooperative isothiourea and Brønsted acid catalysis is demonstrated. The scope and limitations of this process are explored (25 examples, up to 94% yield and 96:4 er), with applications to the synthesis of (S)‐Venlafaxine·HCl and (S)‐Nakinadine B. Mechanistic studies are consistent with a C(1)‐ammonium enolate pathway being followed rather than an alternative dynamic kinetic resolution process. Control studies indicate that (i) a linear effect between catalyst and product er is observed; (ii) an acyl ammonium ion can be used as a precatalyst; (iii) reversible isothiourea addition to an in situ generated iminium ion leads to an off‐cycle intermediate that can be used as a productive precatalyst.
Citation
Zhao , F , Shu , C , Young , C M , Carpenter-Warren , C , Slawin , A M Z & Smith , A D 2021 , ' Enantioselective synthesis of α-aryl-β 2 -amino-esters by cooperative isothiourea and Brønsted acid catalysis ' , Angewandte Chemie International Edition , vol. 60 , no. 21 , pp. 11892-11900 . https://doi.org/10.1002/anie.202016220
Publication
Angewandte Chemie International Edition
Status
Peer reviewed
ISSN
1433-7851Type
Journal article
Description
Funding: The research leading to these results has received funding from the Royal Society (Newton Fellowship Programme, F. Z.; C. S.). A.D.S. thanks the Royal Society for a Wolfson Research Merit Award.Collections
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