Large‐scale preparation of linoleic acid‐d 2 ‐enriched triglycerides from Crepis alpina seed oil

Catalytic deuteration of Crepis 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 (D 2 ) gas. Purification (silica gel) resulted in > 150‐g samples of triglyceride containing 74% cis ‐9, cis ‐12‐octadecadienoic acid‐12,13‐d 2 (18:2‐d 2 ) and 14% unlabelled linoleic acid. Pure (> 99%) tricrepenynin was recovered by further fractionation of the Crepis alpina triglycerides on silica gel. Deuteration of this sample produced deuteriumlabelled trilinolein containing linoleic acid‐d 2 of > 98% isotopic purity.