A Dication-Mediated Rapid 4-Amination of Methoxy Pyridine
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Updated: Oct 31, 2026

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Yang Liu1, Daniel Brüx2, Florian Kleemiss2
1Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074Aachen, Germany.
Abstract:
4-Aminopyridines are key structures in pharmaceuticals. SNAr reactions typically require electron-deficient starting materials, and it remains difficult to overcome this limitation without the use of transition metals. Herein, we report the urea-based organic dication as a highly effective reagent for the activation of 4-methoxypyridine with respect to amination reactions. This method broadly tolerates functional groups, including electron-withdrawing and -donating substituents and even free nucleophiles. This method allows chromatographic procedures to be bypassed during workups, ultimately leading to a more sustainable profile.
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