Process for the preparation of highly optical pure carvedilol

Provided is a process for the preparation of highly optical pure chiral carvedilol, which is able to perform the process under mild condition, eliminate a special purification process, and inhibit lowering of optical purity caused by racemization of chiral carvedilol. The process for the preparation of highly optical pure chiral carvedilol represented by the formula(1) comprises the steps of: (a) reacting amine compounds represented by the formula(4) with chiral glycidol represented by the formula(5) to induce cycle opening and cyclization of the chiral glycidol, and deprotecting a hydroxyl-protecting group of the resulting product to prepare compounds represented by the formula(2); (b) reacting the compounds represented by the formula(2) with halogenizing agent, sulfonating agent or Mitsunobu reagent to activate the hydroxy group and nucleophilic substituting the resulting product with 9H-4-hydroxy carbazole to prepare compounds represented by the formula(7); and (c) deprotecting the compounds represented by the formula(7), wherein X is oxygen or sulfur, Y is a leaving group, and R1 is a hydroxy-protecting group.