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Updated: Dec 5, 2025

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A Bispidine-Based Chiral Amine Catalyst for Asymmetric Mannich Reaction of Ketones with Isatin Ketimines
Gonglin Li1, Mohuizi Liu1, Sijia Zou1
1Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China.
Abstract:
A unique chiral amine organocatalyst with a bispidine structure was found to be efficient for the diastereo- and enantioselective Mannich reaction of isatin ketimines with ketones. A series of 3-substituted 3-amino-2-oxindoles bearing vicinal tertiary and quaternary chiral stereogenic centers were obtained in excellent yields with excellent dr and ee values. The gram-scale synthesis and transformation of the product showed the practicability of this methodology. In addition, a possible transition state model was proposed to explain the origin of the stereoselectivity.
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