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ChemicalBook CAS DataBase List 2,3,4,6-TETRA-O-PIVALOYL-ALPHA-D-GLUCOPYRANOSYL BROMIDE
81058-27-7

2,3,4,6-TETRA-O-PIVALOYL-ALPHA-D-GLUCOPYRANOSYL BROMIDE synthesis

8synthesis methods
-

Yield:81058-27-7 83%

Reaction Conditions:

with trimethylsilyl bromide;zinc dibromide in dichloromethane at 10 - 25;Inert atmosphere;Temperature;

Steps:

Preparation of intermediate IV:
In a 20L four-necked reaction flask,Access N2,750 g of pentaacetate triamine,Dichloromethane,Zinc bromide, stirring evenly.The reaction solution was cooled to 10 ° C,A mixture of trimethylbromosilane and methylene chloride was added dropwise,1.5h drop is completed.Control temperature 20-25 ,The reaction was stirred for 1.5 h. HPLC to the end of the reaction. The zinc bromide was filtered off, yielding a yellow clear liquid. Cooling to 0 ° C, dropping sodium bicarbonate aqueous solution, monitoring pH value of 7-8. The organic layer was dried over anhydrous Na? SO? And filtered. The organic layer was concentrated under reduced pressure to give 700 g of pale yellow solid, 88% pure. Isopropanol to obtain 599.7 g of product, yield 83%, purity 97.5%. The total yield was 68.06%.

References:

Haimen Rui Pharmaceutical Technology Co., Ltd;Xue, Song CN103980263, 2016, B Location in patent:Paragraph 0062

FullText

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