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Improved methodologies for the preparation of highly substituted pyridines. | LitMetric

Improved methodologies for the preparation of highly substituted pyridines.

J Org Chem

Department of Chemistry, University of York, Heslington, York YO10 5DD, UK.

Published: November 2005

[reaction: see text] Two separate strategies have been developed for the preparation of highly substituted pyridines from 1,2,4-triazines via the inverse-electron-demand Diels-Alder reaction: a microwave-promoted, solvent-free procedure and a tethered imine-enamine (TIE) approach. Both routes avoid the need for a discrete aromatization step and offer significant advantages over the classical methods, giving a wide variety of tri-, tetra-, and penta-substituted pyridines in high, optimized yields.

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Source
http://dx.doi.org/10.1021/jo0518304DOI Listing

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