Hydrogenation of linolenate. X. Comparison of products formed with platinum and nickel catalysts

One mole of hydrogen/mole of ester was added to methyl linolenate over a platinum catalyst at 20C and atmospheric pressure. The product was separated into trienoic, dienoic and monenoic esters by countercurrent distribution (CCD) with acetonitrile and hexane. Bach of these ester fractions was further separated by CCD with methanolic silver nitrate and hexane. Comparison with hydrogȳnations, in which a commercial nickel catalyst at 140C and atmos‐pheric pressure was used, shows that with plati‐num more stȳarate is formed; i.e., the platinum hydrogȳnation was less selective. Also, a smaller amt of trans esters was formed with platinum, and there was less shift of double bonds from the original 9, 12 and 15 positions.