As the h-st step in a systematic study of the more important n-octadecenoic acids, the cis isomers of 7-through 12-octadecenoic acids were prepared by partial hydrogenation of the corresponding synthetic octadecynoic acids. Isomerization of the cis acids in the presence of selenium yielded the trans forms. 17-Octadecenoic acid was obtained by condensing the Grignard reagent of 10-undecenyl bromide with 6-carbethoxycaproyl chloride to form ethyl ...
