2-氯-4-氟-5-硝基苯甲酸的制备方法
By using the nitration-hydrolysis reaction of 2-chloro-4-fluorobenzonitrile with sulfuric acid and nitric acid, the problems of poor selectivity and high cost in the existing technology have been solved, and the synthesis of 2-chloro-4-fluoro-5-nitrobenzoic acid with high selectivity has been achieved, which is suitable for industrial production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NUTRICHEM LAB CO LTD
- Filing Date
- 2024-07-26
- Publication Date
- 2026-07-17
AI Technical Summary
Existing technologies exhibit poor selectivity in the synthesis of 2-chloro-4-fluoro-5-nitrobenzoic acid, generating a 3-position mononitrated isomer, and are costly and difficult to effectively separate and purify.
A one-pot synthesis of 2-chloro-4-fluoro-5-nitrobenzoic acid was achieved by nitrification of 2-chloro-4-fluorobenzonitrile with sulfuric acid and nitric acid, followed by hydrolysis. By controlling the reaction conditions and solvent ratio, the formation of the 3-position mononitrated isomer was avoided.
It significantly improves the selectivity of 2-chloro-4-fluoro-5-nitrobenzoic acid, hardly generates the 3-position mononitrated isomer, simplifies the purification process, saves recrystallization solvent, is easy to operate, and is suitable for industrial production.
Smart Images
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