Studies on Fusaric Acid and Analogous Compounds. III.

Synthesis of 5-Propylpicolinic Acid and 5-Pentylpicolinic Acid

Abstract

It was found by admixture that 5-butylpicolinic acid synthesized by the present writer was identical with fusaric acid, extracted from the culture filtrate of Gibberella fijikuroi of rice plant. 5-Propyl- and 5-pentylpicolinic acids were prepared from 2-methyl-5-ethylpyridine by its derivation to the 5-cyano compound, to 5-propionyl and 5-valeroyl derivatives by the Grignard reaction, to 5-propyl and 5-pentyl derivatives by the Wolff-Kishner reduction, reacted with benzaldehyde to change the 2-methyl to 2-styryl, and finally oxidized with potassium permanganate in acetone. It was found by the examination of the reaction of the cyano group in 3-cyano- and 2-methyl-5-cyanopyridine with the Grignard reagents that there was no great difference in the yield of the ketone formed when the alkyl group of the reagent was methyl, ethyl, propyl, or butyl.