4-Fluorobenzonitrile → Letrozole

Participants

Reaction Steps

U.S. Pat. No. 4,978,672 discloses 4-[alpha-(4-cyanophenyl)-1-(1,2,4-triazolyl)-methyl]benzonitrile and a process for its preparation comprising reacting 4-bromomethyl benzonitrile with 1,2,4-triazole to yield 4-[1-(1,2,4-triazol-1-yl)methyl]benzonitrile. 4-[1-(1,2,4-triazol-1-yl)methyl]benzonitrile is then reacted with 4-fluorobenzonitrile to give 4-[1-(4-cyanophenyl)-1-(1,2,4-triazol-1-yl)methyl]benzonitrile (letrozole).

Provenance & Evidence