The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 05, 2023
Filed:
Feb. 22, 2023
Fudan University, Shanghai, CN;
Fener Chen, Shanghai, CN;
Dang Cheng, Shanghai, CN;
Lulu Wang, Shanghai, CN;
Ge Meng, Shanghai, CN;
Yingtang Ning, Shanghai, CN;
Fudan University, Shanghai, CN;
Abstract
This application relates to pharmaceutical engineering, and more particularly to a continuous-flow preparation method of diclofenac sodium. The continuous-flow preparation method includes: subjecting aniline and chloroacetic acid to amidation to obtain 2-chloro-N-phenylacetamide (3); subjecting 2-chloro-N-phenylacetamide (3) and 2,6-dichlorophenol to continuous condensation to obtain N-(2,6-dichlorophenyl)-2-hydroxy-N-phenylacetamide (5); subjecting N-(2,6-dichlorophenyl)-2-hydroxy-N-phenylacetamide (5) and thionyl chloride to chlorination to obtain N-(2,6-dichlorophenyl)-2-chloro-N-phenylacetamide (6); subjecting N-(2,6-dichlorophenyl)-2-chloro-N-phenylacetamide (6) to Friedel-Crafts alkylation in the presence of aluminum chloride to obtain 1-(2,6-dichlorophenyl)-1,3-dihydro-2H-indol-2-one (7); and subjecting 1-(2,6-dichlorophenyl)-1,3-dihydro-2H-indol-2-one (7) to hydrolysis to obtain the diclofenac sodium.