METHOD FOR PREPARING LEVO-BETAXOLOL HYDROCHLORIDE

摘要

A method for preparing levo-betaxolol hydrochloride is provided. The method includes using p-hydroxyl phenyl ethanol as starting material and obtaining the pure levo-betaxolol hydrochloride by selectively esterifying alcoholic hydroxyl, etherifying phenolic hydroxyl, aminating isopropyl amine and finally etherifying by cyclopropylmethanol and leading HCl to be salified. An important intermediate compound 2(2S)-3-(4-p-toluene sulfonyloxy ethyl phenoxy)-1,2-propylene oxide which is used for preparing the levo-betaxolol hydrochloride, and the preparation method thereof are also provided. Bromotoluene cyclopropane is not used, which is higher in price, unstable and very irritant, the final products are easy to be separated and purified, and the obtained product has higher chemical purity (99.0-100.0%) and optical purity (99.0-100.0%) as well as high yield (total yield is 62%), and is suitable for industrialized production.