EFFICIENT ONE-POT SYNTHESIS OF 3-(POLYFLUOROALKYL)PYRAZOL-4-AMINES

Abstract

A simple convenient one-pot protocol for the synthesis of 5-alkyl/hetaryl-4-amino-3-(polyfluoroalkyl)pyrazoles (4-aminopyrazoles) has been suggested. The method is based on using readily available lithium 3-polyfluoroalkyl-1,3-diketonates and sodium nitrite as starting materials and hydrazine hydrate for cyclization into 4-nitroso-3-(polyfluoroalkyl)pyrazoles, followed by reduction of the latter into target products. Molecular structures of 5-methyl-, 5-(thiophen-2-yl)-, 5-(4-methylphenyl)-, and 5-(pyridin-2-yl)-substituted 3-trifluoromethyl-1H-pyrazol-4-amines have been established by X-ray analysis.