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ChemicalBook CAS DataBase List 3,4-Dimethoxy-2-Methylpyridine
107512-35-6

3,4-Dimethoxy-2-Methylpyridine synthesis

9synthesis methods
3-HYDROXY-2-METHYL-4(1H)-PYRIDINONE

17184-19-9

Dimethyl sulfate

77-78-1

3,4-Dimethoxy-2-Methylpyridine

107512-35-6

General procedure: 38 g of 3-hydroxy-2-methylpyridin-4(1H)-one was added to a reaction flask and dissolved in a mixed solution of 90 g of water and 35 g of potassium hydroxide with stirring. The reaction temperature was controlled at 10~20°C. 75 g of dimethyl sulfate was slowly added dropwise, and the reaction was held at the same temperature for 20 hours after the dropwise addition. After completion of the reaction, 80 g of dichloromethane was added to the reaction mixture, stirred for 15 minutes and left to stratify. The aqueous layer was extracted once more with 20 g of dichloromethane, stirred for 15 minutes and left to stratify. The two dichloromethane layers were combined and concentrated under reduced pressure. The product was dried under reduced pressure to give 44 g of 3,4-dimethoxy-2-methylpyridine.

-

Yield: 44 g

Reaction Conditions:

with potassium hydroxide in water at 10 - 20; for 20 h;

Steps:

5 Example 5: Preparation of 3,4-dimethoxy-2-methylpyridine.
38 g of 3-hydroxy-2-methyl-4-pyridone was added to the reaction flask, 90 g of water, and 35 g of potassium hydroxide were stirred and dissolved.Add 75g of dimethyl sulfate at 10~20°C, and keep warm for 20h.After adding 80 g of dichloromethane and stirring for 15 minutes, the layers were separated, and the aqueous layer was stirred with 20 g of dichloromethane for 15 minutes and then layered.The methylene chloride layers were combined and evaporated under reduced pressure to dryness to give 44 g of 3,4-dimethoxy-2-methylpyridine.

References:

Shouguang Fukang Pharmaceutical Co., Ltd.;Dong Liangjun;Sun Jiguo;Liu Jie;Guo Jianhui;Jia Zongqing;Yang Dawei;Wang Haipeng;Wang Hongming;Hou Junjie CN104557692, 2018, B Location in patent:Paragraph 0030; 0031

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