Alkali isomerization of linoleate isomers: Characterization of products

Abstract Geometrical isomers of methyl linoleate were reacted with alakli, and the resulting conjugated isomers were separated intotrans,trans;cis,trans; andcis,cis fractions. The position of double bonds in the various fractions was determined by reductive ozonolysis.trans‐9,trans‐12‐Isomer of linoleate formedtrans,trans‐ andcis,trans‐conjugated dienes, whereascis‐9,trans‐12‐ andtrans‐9,cis‐12‐isomers in addition formedcis,cis‐conjugated dienes. The formation of the products is in accordance with the theoretical predictions. During conjugationtrans double bonds shifted to form atrans bond preferentially. During conjugation ofcis‐9,trans‐12‐ andtrans‐9,cis‐12‐linoleate isomers, thecis double bond shifted preferentially over thetrans double bond. A small amount of diene not conjugated was probably a geometrical and positional isomer of the starting material.