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Updated: Nov 29, 2025

Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
Published on: September 8, 2013
Synthesis of 2,2'-Dihalobiaryls via Cu-Catalyzed Halogenation of Cyclic Diaryliodonium Salts
Kai Zhu1, Zongqiang Song1, Yi Wang1
1College of Pharmaceutical Science, Zhejiang University of Technology, Hangzhou 310014, P. R. China.
Abstract:
We report an efficient method for the preparation of various 2,2'-dihalobiaryls from cyclic diaryliodonium salts. With cheap halogen sources as starting materials, a broad range of 2,2'-diiodobiaryls, 2-bromo-2'-iodobiaryls, and 2-chloro-2'-iodobiaryls were obtained under mild reaction conditions. More importantly, a chiral copper-bisoxazoline catalyst system was further developed for the preparation of axially chiral 2,2'-dihalobiaryls in excellent yields and enantioselectivities, which can serve as versatile precursors for the synthesis of various chiral ligands.
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