Thermal interaction of linoleic acid and its esters with valine

When linoleic acid or its esters were heated in the presence of valine a number of interaction products were formed. The major product was 2‐pentylpyridine which is thought to be produced by the reaction of 2,4‐decadienal with ammonia. Also formed were two secondary amides, isobutyloctanamide and isobutyllinoleylamide. Additional interaction products found include alkylpyridines and alkylpyrroles. The formation of these compounds is similar to the formation of 2‐pentylpyridine. They can result by reaction of an aldehyde with an amine or ammonia to form a Schiff base intermediate, followed by cyclization and rearrangement to form either the pyridine ring or the pyrrole ring. In addition, a branched nitrile compound was produced. This compound is considered to be formed by cleavage of the pyridine ring in 2‐pentylpyridine.