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Updated: Jul 8, 2026

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Direct asymmetric alpha-amination of cyclic ketones catalyzed by siloxyproline
Yujiro Hayashi1, Seiji Aratake, Yoshinaga Imai
1Department of Industrial Chemistry, Faculty of Engineering, Tokyo University of Science, Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan. hayashi@ci.kagu.tus.ac.jp
Abstract:
trans-tert-Butyldimethylsiloxy-L-proline displays greater catalytic activity and affords higher enantioselectivity than the parent proline in the alpha-amination reaction of carbonyl compounds with azodicarboxylate. A quantum mechanical calculation reveals the structure of the transition state. In the presence of a catalytic amount of siloxyproline and water (3-9 equiv), alpha-amino carbonyl derivatives, which are important synthetic intermediates, are obtained in good yield and with excellent enantioselectivity.
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