jo300176f_si_001.pdf (2.96 MB)
Synthesis of Imidazo[4,5-c]pyrazoles via Copper-Catalyzed Amidine Cyclization
journal contribution
posted on 2016-02-21, 15:21 authored by Kostiantyn Liubchak, Andrey Tolmachev, Kostiantyn NazarenkoA new synthetic approach to 4-substituted imidazo[4,5-c]pyrazoles
is proposed on the basis of the N′-(4-halopyrazol-5-yl)amidine
cyclization under the conditions of copper-catalyzed cross-coupling
reactions. Using 5-aminopyrazoles and copper catalysts as starting
materials, the method is inexpensive and convenient and allows a wide
range of substituents at all positions of the imidazo[4,5-c]pyrazole
nucleus.