[Bmim][InCl₄]-Catalyzed Addition of Hydrazones to β-Diketones: An Efficient Regioselective Synthesis of Pyrazoles and Pyrazole-Fused Cyclohexanones

Abstract

The Lewis acidic room-temperature ionic liquid, [bmim][InCl₄], was found to be an efficient catalyst for the regio­selective synthesis of fully substituted pyrazoles and pyrazole-fused cyclohexanones through condensation of hydrazones with symmetrical and unsymmetrical 1,3-diketones. This procedure is simple, ­affording the corresponding products in good to high yields.

Key words

pyrazoles - arylhydrazones - Lewis acid room-temperature ionic liquid - regioselective

• References and Notes

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