ChemicalBook CAS DataBase List 3-Chloropyridin-2-ol

3-Chloropyridin-2-ol synthesis

5synthesis methods

Product Name:3-Chloropyridin-2-ol
CAS Number:13466-35-8
Molecular formula:C5H4ClNO
Molecular Weight:129.54

675-20-7 Synthesis

675-20-7
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$5.00/1g

13466-35-8
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$8.00/250mg

Yield: 93.3%

Reaction Conditions:

Stage #1:piperidin-2-one with triphenyl phosphite;chlorine at 70 - 75;
Stage #2: with sodium hydroxide in water at 40 - 45; for 3 h;Reagent/catalyst;Solvent;Temperature;

Steps:

1-3 Example 3: Preparation of 3-chloro-2-hydroxypyridine (IV)
There is stirring,thermometer,Reflux condenser,In a 500 ml four-necked flask with an air duct and a 30 wt% sodium hydroxide aqueous solution absorption device,Add 150 grams of trichloroethane,49.5 g (0.5 mole) of 2-piperidone (II),0.9 g triphenyl phosphite,Heat and keep between 70-75 ,Slowly introduce 115.0 grams (1.62 moles) of chlorine,Access is completed in about 3-4 hours,Thereafter, the reaction was stirred at 70-75 ° C for 3 hours,Cool to 20-25 Add 170.0 grams (1.7 moles) of 40wt% aqueous sodium hydroxide solution, Stir the reaction at 40-45 for 3 hours,Cool to 20-25 The pH value of the 30wt% hydrochloric acid acidification system is 3.0-4.0,The layers were separated, and the aqueous layer was extracted three times with trichloroethane,50g each time, combine the organic phases, distill the solvent to recover,Drying to obtain 60.4 g of 3-chloro-2-hydroxypyridine solid (IV),The yield was 93.3% and the gas phase purity was 99.6%.

References:

Xin Fa Pharmaceutical Co., Ltd.;Qi Yuxin;Zhang Mingfeng;Ju Lizhu;Wang Quanlong CN110818621, 2020, A Location in patent:Paragraph 0046-0051; 0061-0062

13466-43-8 Synthesis