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ChemicalBook CAS DataBase List Ascorbyl Palmitate
137-66-6

Ascorbyl Palmitate synthesis

10synthesis methods
Ascorbyl palmitate is prepared synthetically by the reaction of ascorbic acid with sulfuric acid followed by reesterification with palmitic acid.
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Yield:137-66-6 91.3%

Reaction Conditions:

Stage #1:1-hexadecylcarboxylic acid;ascorbic acid with sulfuric acid at 18; for 15 h;
Stage #2:palmitic anhydride at 28; for 20 h;Temperature;

Steps:

2
(1)500g of concentrated sulfuric acid was added to the three-necked flask, add 50g of palmitic acid, stirring to dissolve Solution in concentrated sulfuric acid was added 50gL- ascorbic acid, 18 ° C reaction 15h; (2)50g palmitic anhydride was added to the reaction mixture, the temperature was raised to 28 ° C, the reaction 20h, then After adding 10g of activated carbon and stirred for 15min; (3)The step (2) in the resulting mixture is added to 1250ml10 ° C cold water, filtered The filter cake is too crude, the crude product was rinsed with 100ml water, then washed with water after the crude product was dissolved in 750ml of butyl acetate, 50 ° C incubation decolorization 30min. Filtered and allowed to stand, stratification, the upper organic layer (Product containing layer) 50 ° C, washed twice with water, water per 500ml. After washing to the water layer, The organic layer was distilled off under reduced pressure to 400ml of butyl acetate, allowed to stand for cooling to 15 ° C, the solid was filtered off with 50ml The resulting solid was rinsed with ethyl acetate, drained, placed in a vacuum drying oven at 50 ° C. L-ascorbic acid-6-palmitate was obtained as a white flake with a purity of 98. 1% and a yield of 91.3%.

References:

Zhejiang Tianxin Pharmaceutical Co Ltd;Zhang, genbao;Xu, YongZhi;Dang, DengFeng CN105315244, 2016, A Location in patent:Paragraph 0047-0050

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