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ChemicalBook CAS DataBase List Parecoxib
198470-84-7

Parecoxib synthesis

9synthesis methods
-

Yield:198470-84-7 97.7%

Reaction Conditions:

with benzenesulfonic acid at 50; for 2 h;Reagent/catalyst;Temperature;

Steps:

1.3; 2.3; 3.3; 4.3; 5.3 3. Preparation of parecoxib (formula 4 compound)
Weighed 15g (47.7mmol, 1e.q) of valdecoxib (compound of formula 3),Add to 22.5ml of propionic anhydride (238.5mmol, 5e.q), stir and heat to raise the temperature to 50 ° C,Add 0.076 g (4.8 mmol, 0.1 e.q) benzenesulfonic acid, react for 120 minutes, and cool to room temperature (15-30 ° C).Crystallization, filtration, vacuum drying at 55±5°C, vacuum degree -0.070-0.082Mpa for 4-6h,17.27 g of parecoxib was obtained, the yield was 97.7%, and the purity was 99.9% by HPLC.

References:

Kunyao Group Co., Ltd.;Xi Liang;Zhu Changcheng;Jin Yi;Ba Dewei;Wen Na;Hu Yanchao CN110256370, 2019, A Location in patent:Paragraph 0043; 0048-0049; 0052; 0057-0058; 0061; 0066-0067

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