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Updated: Aug 9, 2026

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Structurally well-defined, recoverable C3-symmetric tris(beta-hydroxy phosphoramide)-catalyzed enantioselective
Da-Ming Du1, Tao Fang, Jiaxi Xu
1Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China. dudm@pku.edu.cn
Abstract:
[reaction: see text] A series of new chiral C(3)-symmetric tris(beta-hydroxy phosphoramide) ligands have been synthesized via the reaction of trisphosphoramide ester and Grignard reagents. The catalytic asymmetric borane reduction of ketones with these new C(3)-symmetric chiral tris(beta-hydroxy phosphoramide)s was investigated. Structurally well-defined, recoverable ligand 1d is an efficient catalyst for the enantioselective borane reduction of both electron-deficient and electron-rich ketones, and high enantioselectivities were achieved (up to 98% ee).
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