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ChemicalBook CAS DataBase List Arbutin
497-76-7

Arbutin synthesis

7synthesis methods
-

Yield:497-76-7 90%

Reaction Conditions:

with ammonium chloride in water at 70; for 2 h;Concentration;

Steps:

1 Example 1

Tetraacetyl arbutin 44g (0.1mol) into the three-necked flask with stirring, was added 200ml of toluene, stirringDissolved, warmed to 60 ° C, 112 g (0.11 mol) of acetic anhydride was slowly added dropwise, and the addition was completed within half an hour. Stirring was continued for 1 hour, and the toluene was distilled off under reduced pressure to obtain pentacetyl arbutin solid. Then directly add 80g (0.15mol) of 10% ammonium chloride aqueous solution to the flask, raise the temperature to 70 ° C, stir for 2 hours, cool down to room temperature, precipitate crystals, filter and dry to obtain arbutin 24.5g, yield 90 %.

References:

CN107216359,2017,A Location in patent:Paragraph 0022; 0023; 0024; 0025; 0026; 0027

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