An Efficient One-Pot Synthesis of 1,3,5-Substitutec-1 H -Pyrazoles Derivatives

Abstract

One-pot reaction between dialkyl acetylendicarboxylates and different hydrazide acids in the presence of triphenylphosphine leds to 1,3,5-substituted-1H-pyrazoles derivatives in excellent yields. In the absence of triphenylphosphine, dialkyl acetylenedicarboxylate adds to hydrazide acids to produce dialkyl 2-(arylhydrazono)succinates were obtained in good yields.