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Updated: Aug 6, 2026

Preparation of Enantiopure Non-Activated Aziridines and Synthesis of Biemamide B, D, and epiallo-Isomuscarine
Published on: June 13, 2022
Alkyne Migratory Insertion Enabled Dynamic Kinetic Asymmetric Dearomatization of Unactivated Racemic Biaryls
Yongjian Yang1, Xuening Li2, Qianyong He1
1Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education), Key Laboratory of Phytochemistry R&D of Hunan Province, and Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, Institute of Interdisciplinary Studies, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, Hunan, 410081, China.
Abstract:
Catalytic asymmetric dearomatization has emerged as an effective approach for transforming planar aromatic compounds into valuable three-dimensional chiral architectures. Herein, we report a palladium-catalyzed enantioconvergent dearomatization of non-activated naphthalene derivatives via alkyne migratory insertion. Unlike existing methods that convert racemic biaryl substrates into enantiopure compounds, this work represents a rare strategy for dynamic kinetic asymmetric dearomatization of racemic unactivated biaryl systems. A custom-designed asymmetric polyfluorinated phosphoramidite ligand enables high reactivity and stereocontrol. Mechanistic studies confirmed an enantioconvergent pathway, converting configurationally labile biaryl substrates into enantioenriched spiro frameworks. A linear correlation between product and ligand enantiopurity supports a 1:1 Pd/ligand ratio in the active catalytic species, with density functional theory calculations offering further mechanistic insight. The synthetic utility was further demonstrated through scale-up reactions and downstream derivatizations, including a central-to-axial chirality transfer process.
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