Chromatographic separation of the stereoisomers of α‐tocopherol

The diastereoisomers of2‐ambo‐α‐tocopherol were completely separated as TMS ethers by gas chromatography on a 115 m × 0.25 mm glass capillary column coated with SP2340, at a column temperature of 195 C. In the same way,all‐rac‐α‐tocopherol was separated into four peaks, corresponding to the four racemates present, and having the same retention ratios as the four diastereoisomers of 4′‐ambo‐8′‐ambo‐α‐tocopherol (produced by the hydrogenation of natural α‐tocotrienol). Retention data and relative peak areas for the diastereoisomers of the synthesized α‐tocopherols and several commercial products were determined. Limited data on the isomers of other tocopherols also are reported.