Enantioselective Pictet-Spengler Reaction of Acyclic α-Ketoesters Using Chiral Imidazoline-Phosphoric Acid Catalysts.

Org Lett

The Institute of Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki-shi, Osaka 567-0047, Japan.

Published: February 2022

The first enantioselective Pictet-Spengler reaction of acyclic α-ketoesters with tryptamines has been developed. Excellent yields and enantioselectivity were obtained for the reaction using chiral imidazoline-phosphoric acid catalysts. Density functional theory calculations suggested possible transition states that explain the origin of chiral induction. This process provides an efficient route for the synthesis of tetrahydro-β-carboline derivatives.

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http://dx.doi.org/10.1021/acs.orglett.1c04316DOI Listing

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