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ChemicalBook CAS DataBase List 3,4-DIHYDROXY-5-METHOXYBENZOIC ACID METHYL ESTER
3934-86-9

3,4-DIHYDROXY-5-METHOXYBENZOIC ACID METHYL ESTER synthesis

10synthesis methods
Methyl 3,4-dihydroxy-5-methoxybenzoate is synthesizede by esterified with gallic acid and then etherified with dimethyl sulfate.
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Yield: 92%

Reaction Conditions:

with potassium carbonate in acetone at 22; for 4.5 h;Temperature;

Steps:

1.2; 2.2; 3.2 2. Synthesis of methylated compounds:
Add 20g (102.0mmol) of carbonate, 100ml of acetone, and 28.2g (204.2mmol) of potassium carbonate to the reaction flask.25.7g (204.2mmol) of dimethyl sulfate was added dropwise at a controlled temperature of 22 ° C. After the addition was completed, it was kept at 22 ° C for 4.5 hours.Concentrate the acetone under negative pressure, add 150ml of water, heat up to 50 ± 2 and hold for 2.5 hours,Cool to 8 for 1 hour, filter, rinse with a small amount of ice water, and dry to obtain 18.6g of methylated compound, yield 92%.

References:

Suzhou Chenghe Pharmaceutical And Chemical Co., Ltd.;Chen Xiaoqiang CN111004206, 2020, A Location in patent:Paragraph 0016-0017; 0021-0022; 0026-0027

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