PROCESS FOR THE PREPARATION OF 2,2'-[5-(1,2,4-TRIAZOLE-1-YLMETHYL) -1,3-PHENYLENE] DI (2-METHYLPROPIONITRILE).

摘要

The present invention discloses a process for the preparation of Anastrozole of the formula I in high purity and in high yield. 3,5-bis(halomethyl)toluene is prepared by reacting mesitylene with N-halosuccinimide in the presence of light or dibenzoyl peroxide or azobis isobutyronitrile as a catalyst and in a chlorinated solvent. 3,5-bis(halomethyl)toluene is cyanated with metal cyanide in the presence of a catalyst and in water, organic solvent or mixture thereof at temperature of 40 to 60° C to obtain 2,2'-(5-methyl-l,3 phenylene)diacetonitrile which is further methylated with iodomethane in the presence of base and an organic solvent at temperature of 0 to 15° C to obtain 2,2'-(5-methyl-l,3-phenylene)di(2-methyl-propiononitrile). The product obtained is treated with N-halosuccinimide in the presence of a catalyst and in a chorinated solvent at temperature of 60 to 100° C to obtain 2,2'-(5-halomethyl-l,3-phenylene)di(2-methyl propionitrile) which was further treated with potassium or sodium salt 1,2,4-triazole at temperature of 20 to 50° C in dimethyl formamide to obtain crude 2,2'-[5-(lH-l,2,4-triazole-l-ylmethyl)-l,3-phenylene]di(2- methylpropionitrile). The crude product is purified by column chromatography using a stationary phase and a mobile phase followed by recrystallization with a solvent or mixture of solvents to obtain highly pure Anastrozole.