2-Methoxy-5-sulfonamide ethyl benzoate is an important intermediate for the antipsychotic drugs sulpiride and levosulpiride. Sulpiride, chemically named N-[(1-ethyl-2-pyrrolyl)methyl]-2-methoxy-5-(aminosulfonyl)benzamide, was synthesized by the French in 1967. Due to its therapeutic effects on mental disorders and few adverse reactions, it has been used clinically both domestically and internationally for many years.
In a 1000ml reaction flask equipped with reflux device will be added 300g tetrahydrofuran, 0.25mol2-methoxy-5-chlorobenzoic acid ethyl ester, 1.8g of copper bromide (0.0125mol), 25.7g (0.25mol) of sodium sulfamate, heating to 65 C, and maintained at this temperature for 12 hours, the end of the insulation, in the reaction solution added 2g of activated carbon Filtered while hot, the filtrate was concentrated to dry under reduced pressure, dried in vacuum at 60 to obtain 2-methoxy-5-sulfamoylbenzoic acid ethyl ester white crystalline powder foam 57.9g (0.236mol), yield 94.5%, content 99.51% (HPLC). Among the HPLC detection conditions: mobile phase: 700 ml of water; methanol 200 ml. Detection wavelength: 240 nm, flow rate 1.0 ml/min, sample 0.01 g, diluted to 25 ml with mobile phase, injection volume 5 l.
