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Updated: Sep 25, 2025

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Solvent-Free Strategy for Direct Access to Versatile Quaternary Ammonium Salts with Complete Atom Economy
Weibin Fan1,2, Yuan Zhang1, Yinghua Li1
1State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian 350002, P. R. China.
Abstract:
A solvent-free method for the synthesis of quaternary ammonium salts (QAS) by iodoquaternization of alkenes with N-heteroarenes was reported. Its advantages lie in energy-saving and clean production by using iodine as the oxidant and manual grinding the starting materials, together with the complete atom economy and low process mass intensity (PMI) value. Demonstrated by 50 examples, the generated QAS was proved to be able to produce valuable chemicals, such as biological protease inhibitors, anti-cancer agents, and organic fluorescent materials.
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