An atom efficient, green synthesis of 2-pyrazoline derivatives under solvent-free conditions using grinding technique

A simple, rapid, efficient, and environmentally benign procedure for synthesis of 2-pyrazoline derivatives has been achieved by reacting 2′-hydroxychalcones with hydrazine hydrate under solvent-free grinding technique. The short reaction time, cleaner reaction, easy workup, higher yields, and mild reaction conditions make this protocol practical and economically attractive in comparison with the classical reaction.