Large-scale preparation of linoleic acid-d2-enriched triglycerides fromCrepis alpina seed oil

Catalytic deuteration ofCrepis alpina seed oil provided a convenient one-step method for the direct synthesis of large quantities of triglycerides enriched with deuteriumlabelled linoleic acid.Crepis alpina seed (19 kg) was crushed, and the oil [74% crepenynic acid (cis-9-octadecen-12-ynoic acid)] was extracted with hexane. After purification by column chromatography (silica gel), > 170-g batches of oil were deuterated with Lindlar catalyst and deuterium (D2) gas. Purification (silica gel) resulted in > 150-g samples of triglyceride containing 74%cis-9,cis-12-octadecadienoic acid-12,13-d2 (18:2-d2) and 14% unlabelled linoleic acid. Pure (> 99%) tricrepenynin was recovered by further fractionation of theCrepis alpina triglycerides on silica gel. Deuteration of this sample produced deuteriumlabelled trilinolein containing linoleic acid-d2 of > 98% isotopic purity.