The methyl group in 2- and 4- picolines is reactive; e.g., 2-picolines condenses with acetaldehyde in the presence of warm aqueous sodium hydroxide to form 2-propenylpyridine.
[2] In 1849, the Scottish chemist Thomas Anderson (1819 – 1874) prepared picoline in pure form, from coal tar and via the pyrolysis of bones.
[4][5] By 1870, the German chemist Adolf von Baeyer had synthesized picoline in two ways: by the dry distillation of acroleïnammoniak (CH2=CH-CH=N-CHOH-CH=CH2)[6] and by heating tribromallyl (1,2,3-tribromopropane) with ammonia in ethanol.
Weidel then subjected each isomer of picoline to oxidation by potassium permanganate, transforming each into a carboxylic acid.
[14] However, Weidel did not determine, for any of the three isomers, the position of the methyl group in relation to the nitrogen atom of the pyridine nucleus.