An efficient and green one-pot three-component synthesis of 4,4′-(arylmethylene)bis(1H-pyrazol-5-ol)s catalyzed by 2-hydroxy ethylammonium propionate

Abstract

A simple and efficient one-pot synthetic protocol for the 4,4′-(arylmethylene)bis(1H-pyrazol-5-ol)s was developed by condensation reaction of aromatic aldehydes, ethyl acetoacetate, and phenylhydrazine/hydrazine hydrate catalyzed by 2-hydroxy ethylammonium propionate under solvent-free conditions. The remarkable features of this new protocol are high yields, short reaction times, easy workup, reusability of inexpensive ionic liquid, and environmentally benignancy.