A practical, two-step synthesis of 1-alkyl-4-aminopyrazoles

✍ Scribed by Anna A. Zabierek; Kaleen M. Konrad; Andrew M. Haidle

• Publisher: Elsevier Science
• Year: 2008
• Tongue: French
• Weight: 153 KB
• Volume: 49
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/j.tetlet.2008.02.169

✦ Synopsis

A novel synthesis of N1 alkyl-substituted pyrazoles with a free amino group at the C4 position is described. Commercially available 4nitropyrazole was found to readily undergo Mitsunobu reactions with primary and secondary alcohols. Subsequent reduction of the nitro group via hydrogenation affords 1-alkyl-4-aminopyrazoles, which are valuable intermediates in the synthesis of pharmaceutically active compounds.