112809-26-4

Basic information

• Product Name: Benzonitrile, 4-(1H-1,2,4-triazol-1-ylmethyl)-, monohydrochloride
• CAS NO: 112809-26-4
• Molecular Formula: C10H8N4.ClH
• Molecular Weight: 220.661
• Mol File: 112809-26-4.mol
• Article Data: 4

Chemical Properties

• CAS DataBase Reference: Benzonitrile, 4-(1H-1,2,4-triazol-1-ylmethyl)-, monohydrochloride(CAS DataBase Reference)
• NIST Chemistry Reference: Benzonitrile, 4-(1H-1,2,4-triazol-1-ylmethyl)-, monohydrochloride(112809-26-4)
• EPA Substance Registry System: Benzonitrile, 4-(1H-1,2,4-triazol-1-ylmethyl)-, monohydrochloride(112809-26-4)

Safety Data

• Hazardous Substances Data: 112809-26-4(Hazardous Substances Data)

Upstream product

• 288-88-0 1,2,4-Triazole 
• 17201-43-3 4-cyanobenzyl bromide 
• 112809-27-5 4-[(1-(1,3,4-triazolyl)-methyl)]benzonitrile 
• 112809-25-3 4-((1H-1,2,4-triazole-1-yl)methyl)benzonitrile 

Downstream Products

• 112809-51-5 letrozol 
• 112809-25-3 4-((1H-1,2,4-triazole-1-yl)methyl)benzonitrile 

Relevant articles and documents

PROCESS FOR PREPARATION OF LETROZOLE AND ITS INTERMEDIATES

The present invention relates to an improved process for preparation of the non-steroidal aromatase inhibitor drug, Letrozole of formula (I) and its intermediates, 4-[1-(1,2,4-triazolyl)methyl]-benzonitrile of formula (IV) and 4-[1-(1,2,4-triazolyl)methyl]-benzonitrile hydrochloride of formula (VII), all having a purity of ≧99%, which is simple, convenient, economical, does not use hazardous chemicals and industrially viable.

Process for the preparation of letrozole

The invention provides a high-yield process for the preparation of letrozole having a high purity, without the need for removal of the 4-[1-(1,3,4-triazolyl)methyl]benzonitrile impurity at the intermediate stage. The invention also provides a process for the synthesis of letrozole in which formation of the impurity 4-[1-(1,3,4-triazolyl)methyl]benzonitrile during the first stage is minimized. In the process, a 4-(halomethyl)benzonitrile is reacted with a salt of 1H-1,2,4-triazole, reducing the formation of the impurity. Preferably, the preparation is conducted as a one-pot process.