Deuterium‐hydrogen exchange during the catalytic deuteration of methyl oleate

Extensive exchange of deuterium for carbonbonded hydrogen takes place during the catalytic reduction of methyl oleate with gaseous deuterium. Mass spectrometric analysis of the deuterated stearate shows that it is composed as follows: a small part of one molecular species contains no deuterium; the largest contains 1 atom of deuterium; nearly as much contains 2 atoms; and progressively smaller numbers of molecules contain 3,4,5, and up to 11 atoms of deuterium per molecule. No appreciable exchange occurred with the hydrogen of methyl stearate in the presence of active palladium catalyst and deuterium. Methyl oleate, containing up to 9 atoms of deuterium in one species and 11/2 moles of deuterium average per mole, has been separated from the partially deuterated ester. This octadecenoate has 60舑65% of its double bonds intrans configuration and only 18% of its double bonds in the original 9,10‐position.