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ChemicalBook CAS DataBase List D-alpha-Tocopheryl acetate
58-95-7

D-alpha-Tocopheryl acetate synthesis

12synthesis methods

A method of preparing vitamin E acetate, characterized in that it comprises the steps of:

(1) add 2,3,5-trimethylhydroquinone and catalyst composed of concentrated sulfuric acid, copper sulfate, tin chloride to the reaction solvent, stir until

-

Yield:58-95-7 99.37%

Reaction Conditions:

with dmap in toluene at 65; for 5 h;Large scale;Solvent;

Steps:

2 Example 2

To 4650 kg of tocopherol (97.0%), 4650 kg of toluene, 1700 kg of acetic anhydride and 6.6 kg of DMAP were used for the esterification reaction, the reaction temperature was 65 , the reaction time was 5 h, the residual tocopherol was 0.09% (Toluene, acetic acid, acetic anhydride) was added to the residue, and the pH was adjusted to 6 to 7 by adding 35% hydrochloric acid to the residue after distilling off the solvent. 200 kg of hot water was further added and the mixture was stirred to dissolve and the resulting aqueous layer was concentrated After the concentrated treatment, the test basically does not contain tocopherol or vitamin E acetate, mainly DMAP hydrochloride. The upper layer was further washed with 500 kg of hot water and the toluene was further removed to recover the toluene to the condensation reaction of the synthetic tocopherol. After removal of the toluene VE crude oil, 5148 kg of vitamin E acetate with a content of 98.5% was obtained by distillation and the residual amount of tocopherol was 0.44%. According to the yield of vitamin E acetate, the yield was 99.37%. The appearance of vitamin E acetate product was clear and transparent, and the retention time of the product was consistent with the standard after HPLC detection.

References:

CN105801551,2016,A Location in patent:Paragraph 0026; 0027

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