Ionic-Liquid Salt-Mediated Synthesis of 4′-(Pyridyl)-terpyridines

Abstract

One-pot reactions to produce isomeric 4′-(pyridyl) 2,2′:6′,2″-terpyridine under moderate conditions are described using imidazolium-based ionic liquid and quaternary ammonium-based molten salts as solvent media. The use of eutectic molten salts as a reaction media proved effective in sequential aldol and Michael addition reactions, leading to substituted terpyridines. The desired product was obtained in reasonable yield via a simple, one-pot reaction.

Keywords:

• Green chemistry
• ionic liquid
• quaternary ammonium salts
• terpyridines

ACKNOWLEDGMENTS

We gratefully acknowledge the Council of Scientific and Industrial Research, New Delhi, India, for funding under the network project NWP-0010. We also thank the Analytical Sciences Discipline of the institute for analysis facilities.

Notes

^a IL 1, 1-butyl 3-methyl imidazolium tetrafluoroborate; salt 1, di-ethylenetriamine sulfate; salt 2, n-propylamine sulfate.

^b Theoretically calculated elemental analysis results are C = 77.4%, H = 4.55%, and N = 18.05%.