DL-alpha-Tocopherol → Alpha-Tocopherol Acetate

Participants

Reaction Steps

2.283 g of TMHQ and 0.236 g of metallic zinc powder were suspended in 11.8 ml of ligroin in an atmosphere of nitrogen. A solution of 4.943 g of phytyl chloride [purity 95.7%] in 7.9 ml of ligroin was dripped into said suspension under agitation and refluxed for a period of 2 hours 15 minutes. The suspension was heated and subjected to reflux for another 3 hours to obtain a reaction mixture of dl-α-tocopherol. 11.5 ml of acetic anhydride and 0.218 g of γ-picoline were added to the reaction mixture, which was then refluxed for 5 hours, to obtain 7.118 g of dl-α-tocopheryl acetate which reflected a pale yellow coloring. The absorbance of this dl-α-tocopheryl acetate was determined to be E415 mμ40%EtOH =0.098. Estimation of the dl-α-tocopheryl acetate by high pressure liquid chromatography with the use of n-nonane as the standard substance indicated that its purity was 84.4% and the yield was 84.7%.

Provenance & Evidence