| abstract |
The present invention relates to a method for the efficient preparation of chiral carvedilol of high optical purity. According to the present invention, chiral oxazolidin-2-ones or oxazolidines having the formula (II) prepared using N-protected 2- (2-methoxyphenoxy) ethylamine and chiral glycidol derivatives 2-thione compounds are used as key intermediates in the preparation of chiral carvedilols. Specifically, the method for preparing chiral carvedilol according to the present invention comprises: a) reacting a compound having Formula 2 with a halogenating agent, sulfonating agent or mizunobu reagent to activate the hydroxy group present in the compound of Formula 2, and then 9H. Subjecting to 4-nucleophilic substitution with hydroxy carbazole to obtain a compound having formula (7), b) applying the obtained compound of formula (7) to deprotection in the presence of an inorganic base to provide the desired chiral carvedilol It comprises a step. In the method for preparing chiral carvedilol according to the present invention, the reaction conditions are mild, no special purification process is required, and the optical purity decrease caused by racemization of chiral carvedilol does not occur. Thus, the process according to the invention provides a chiral carvedilol of high optical purity simply and efficiently. |