Greener Synthetic Approach for 4,4?-(Arylmethylene)bis(3-methyl-1H-pyrazol-5-ol) Derivatives in an Aqueous Medium using Theophylline as a Catalyst

Abstract

Herein, we report an efficient, convenient and environmentally benign method for the synthesis of 4,4?-(arylmethylene)bis(3-methyl-1H-pyrazol-5-ol) derivatives. The reaction of aromatic aldehydes with 3-methyl-1-phenyl-5-pyrazolone or 5-methyl-2,4-dihydro-3H-pyrazol-3-one in the presence of theophylline catalyst delivered the series of bis-pyrazole compounds in very high yields. The method has successfully demonstrated the utility of theophylline as an expedient, eco-friendly and green catalyst in an aqueous medium. � 2023 Wiley-VCH GmbH.