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Updated: Jul 10, 2025

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Protocol for stereodivergent asymmetric hydrogenation of quinoxalines
Mingyang Wang1, Chenguang Liu1, Qiang Liu1
1Center of Basic Molecular Science (CBMS), Department of Chemistry, Tsinghua University, Beijing 100084, China.
Abstract:
Chiral 1,2,3,4-tetrahydroquinoxalines are ubiquitous in natural products and bioactive molecules. Herein, we disclose a protocol for stereodivergent asymmetric hydrogenation of disubstituted quinoxalines for the preparation of both cis- and trans-enantioenriched disubstituted tetrahydroquinoxalines (up to >20:1 d.r. and 99% ee). We describe steps for synthesis of ligands and substrate, setup of hydrogenation of disubstituted quinoxalines, and purification of products. Additionally, we provide detailed diagrams of the hydrogenation installation. For complete details on the use and execution of this protocol, please refer to Liu et al.1.
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