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Updated: Dec 30, 2025

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Cu(I)-Catalyzed Enantioselective Alkynylation of Thiochromones
Ling Meng1,2, Ka Yan Ngai1, Xiaoyong Chang1
1Shenzhen Grubbs Institute and Department of Chemistry , Southern University of Science and Technology , Shenzhen 518055 , China.
Abstract:
A highly efficient asymmetric synthesis of chiral thiochromanones is developed via Cu(I)/phosphoramidite catalyzed asymmetric alkynylation of thiochromones under mild reaction conditions. The catalyst system is tolerant of various thiochromone precursors and terminal alkynes. The established asymmetric transformation provides different enatiomeric-enriched thiochromanones with more molecular complexity and enables access to chiral thioflavanones, a subgroup of flavonoid by further functionalization.
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