4-Methoxyphenylacetic Acid CAS 104-01-8

The method uses p-methoxyphenylacetic acid and 2-(cyclohexenyl)ethylamine as starting materials through acylation condensation, Bischler-Napieralski ring formation reaction, imine reduction, ether bond hydrolysis, resolution, N-alkane A total of nine steps including alkylation, Grewe cyclization and salt formation. The method obtains levolorphanol tartrate and various intermediates with high yield and high purity, and can be used as an industrial method for large-scale production.

Condensate first, add resorcinol, p-methoxyphenylacetic acid, and boron trifluoride ethyl ether in a dry reactor, heat the reaction, after the reaction is complete, add water, heat to reflux, cool to precipitate crystals, filter, and wash with water until neutral , dry to obtain the intermediate; recyclization, in the dry reaction tank, add the intermediate, triethyl orthoformate, morpholine, DMF and glacial acetic acid, separate the reaction by-product ethanol, heat to reflux, the reaction is completed, and the pressure is reduced Recover the DMF reagent, cool it down, add saturated sodium bicarbonate solution to the residue to reflux, lower the temperature, and precipitate crystals. The crude product formononetin is obtained by conventional treatment, and the refined formononetin is obtained by refining with methanol. The problem of lack of pedicelin resources has the advantages of easy-to-obtain raw materials, high-efficiency reaction, and convenience, and has high application value.

It includes the following steps: (1), adding resorcinol, zinc chloride, and p-methoxyphenylacetic acid into the drying container, vacuuming to within -0.06Mpa, stirring and reacting at 120°C~140°C for 30~120min; (2) After the reaction, cool down to below 100°C, add water to dissolve the material, stir for 30-100 minutes, cool down to 5-30°C, and crystallize; (3) Filter, wash the filter cake with water until neutral, and dry it. product. The invention has a reasonable design, uses zinc chloride as a catalyst, and can prepare the key intermediate of formononetin by adjusting the temperature and pressure, that is, under mild reaction conditions and negative pressure conditions, without special equipment and corrosion to equipment Small safety, fast safety, easy operation, small waste liquid, and little pollution.