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Updated: Sep 24, 2025

Efficient Synthesis of Polyfunctionalized Benzenes in Water via Persulfate-promoted Benzannulation of α,β-Unsaturated Compounds and Alkynes
Published on: December 16, 2019
Dehydrative amination of benzhydrols with electron-withdrawing group-substituted 2-aminopyridines utilizing
Hidemasa Hikawa1, Taku Nakayama1, Shunki Nakamura1
1Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan. hidemasa.hikawa@phar.toho-u.ac.jp.
Abstract:
We report a method for gold(III)/sodium diphenylphosphinobenzene-3-sulfonate (TPPMS)-catalyzed direct amination of benzhydrols using 2-aminopyridines with poor nucleophilic character in water. Various functional groups such as electron-withdrawing nitro, cyano and halogen groups were tolerated well to form the desired N-benzylated 2-aminopyridine compounds. On the basis of mechanistic studies including kinetic profiles, Hammett study and isotope effects, we propose a pathway in which a Lewis acidic gold cation species activates the sp3 C-O bond of the alcohol in the rate-determining step.
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