A method of making a pyrazole compound includes mixing a diazonium salt with a reactant in the presence of a solvent, thereby coupling a diazo group of the diazonium salt to an -carbon atom of the reactant to form a reaction intermediate having a formula of (I) or (II); mixing the reaction intermediate and hydrazine in the presence of a superparamagnetic iron oxide nanoparticles catalyst thereby cyclizing the hydrazine with an ester group of the reaction intermediate to form the pyrazole compound having a formula of (III) or (IV).

##STR00001##

A method of making a pyrazole compound includes mixing a diazonium salt with a reactant in the presence of a solvent, thereby coupling a diazo group of the diazonium salt to an a-carbon atom of the reactant to form a reaction intermediate having a formula of (I) or (II); mixing the reaction intermediate and hydrazine in the presence of a superparamagnetic iron oxide nanoparticles catalyst thereby cyclizing the hydrazine with an ester group of the reaction intermediate to form the pyrazole compound having a formula of (III) or (IV).

##STR00001##

A method of making a pyrazole compound includes mixing a diazonium salt with a reactant in the presence of a solvent, thereby coupling a diazo group of the diazonium salt to an a-carbon atom of the reactant to form a reaction intermediate having a formula of (I) or (II); mixing the reaction intermediate and hydrazine in the presence of a superparamagnetic iron oxide nanoparticles catalyst thereby cyclizing the hydrazine with an ester group of the reaction intermediate to form the pyrazole compound having a formula of (III) or (IV).

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