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Updated: Sep 27, 2025

A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
TMSOTf-mediated Kröhnke pyridine synthesis using HMDS as the nitrogen source under microwave irradiation
Chieh-Kai Chan1, Yi-Hsiu Chung1, Cheng-Chung Wang1
1Institute of Chemistry, Academia Sinica Taipei 115 Taiwan ckc@gate.sinica.edu.tw wangcc@gate.sinica.edu.tw.
Abstract:
An efficient protocol for the preparation of pyridine skeletons has been successfully developed involving the TMSOTf/HMDS (trifluoromethanesulfonic acid/hexamethyldisilane) system for the intermolecular cyclization of chalcones under MW (microwave) irradiation conditions. This method provides a facile approach to synthesize 2,4,6-triaryl or 3-benzyl-2,4,6-triarylpyridines in good to excellent yields. Interestingly, the 2,6-diazabicyclo[2.2.2]oct-2-ene core was obtained by changing the acid additive to Sn(OTf)2, and the desired product was also confirmed using X-ray single-crystal diffraction analysis.
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