Preparation of isopropyl- and t-butyl-pyridines from methylpyridines by phase-transfer catalysed alkylation

Abstract

Methyl groups in the 2,4, and 6 positions of pyridine rings have been converted into isopropyl (2 and 6 positions) and t-butyl (4 position) groups by alkylation of the N-methylpyridinium iodides with methyl iodide, using a phase-transfer catalyst; attempts to prepare 2,6-diethylpyridine, or to alkylate 3-methylpyridine, by this technique were unsuccessful.