Scalable Synthesis of a Chiral Selenium π-Acid Catalyst and Its Use in Enantioselective Iminolactonization of β,γ-Unsaturated AmidesT.H. thanks the Japan Society for the Promotion of Science (KAKENHI Grant Numbers JP16H01021 and JP18H04256 in Precisely Designed Catalysts with Customized Scaffolding, and JP19H02710). K.M. thanks the Japan Society for the Promotion of Science (KAKENHI Grant Numbers JP26220803 and JP17H06450).
Received: 13 May 2019
Accepted after revision: 18 June 2019
28 June 2019 (online)
Published as part of the Cluster Organosulfur and Organoselenium Compounds in Catalysis
Chiral selenium π-acid catalysis has for a long time been lagging behind other areas of asymmetric catalysis due to a lack of highly enantioselective catalysts. In this regard, we recently developed the first chiral selenium π-acid catalyst which performs the oxidative cyclization of β,γ-unsaturated carboxylic acids with high enantioselectivities. We report herein our improved synthesis of this chiral selenium catalyst, which allows access to a large quantity of the catalyst as the diselenide. In addition, the catalyst is tested in the oxidative cyclization of N-methoxy β,γ-unsaturated amides to give iminolactones with high enantioselectivities.
References and Notes
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