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Updated: May 27, 2026
Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)
Published on: January 17, 2020
Well-defined binuclear chiral spiro copper catalysts for enantioselective N-H insertion
Shou-Fei Zhu1, Bin Xu, Guo-Peng Wang
1State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, China.
Abstract:
An asymmetric N-H insertion of α-diazoesters with anilines catalyzed by well-defined copper complexes of chiral spiro bisoxazoline ligands was studied in detail. The copper-catalyzed asymmetric N-H insertion of a wide range of α-alkyl-α-diazoacetates with anilines was accomplished with excellent enantioselectivity (up to 98% ee) and provided an efficient method for the preparation of optically active α-amino acid derivatives. A correlation study of the electronic properties of the substrates with the enantioselectivity of the N-H insertion reaction supports a stepwise insertion mechanism, and the significant first-order kinetic isotope effect proves that the proton transfer is most likely the rate-limiting step. A binuclear chiral spiro copper catalyst having 14-electron copper centers, a trans coordination model, a perfect C(2)-symmetric chiral pocket, and significant Cu-Cu interaction was isolated and extensively studied. The novel structure of the binuclear chiral spiro copper catalyst leads to unique reactivity as well as enantioselectivity in the N-H insertion reaction.
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