A Metal-Free Strategy for the Synthesis of Symmetrical 2,3,5,6-Tetrasubstituted Pyridines Using Triethyl Orthoformate as a Carbon Source

Abstract

A simple and efficient method for the synthesis of symmetric 2,3,5,6-tetrasubstituted pyridines from enaminones and triethyl orthoformate, catalyzed by pyridinium p-toluenesulfonate, has been established in which triethyl orthoformate was applied as a carbon source. The procedure was smoothly executed, culminating in the synthesis of symmetrical 2,3,5,6-tetrasubstituted pyridines with moderate to exceptional yields across a diverse array of substrates.

Key words

pyridines - triethyl orthoformate - pyridinium toluenesulfonate - metal-free reaction

Publication History

Received: 14 June 2024

Accepted after revision: 15 August 2024

Article published online:
02 October 2024

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