Sodium gluconate: An efficient organocatalyst for the synthesis of dihydropyrano[2,3-c] pyrazole derivatives

Sodium gluconate presented as a category of biomolecule found to be a proficient and recyclable organocatalyst for the synthesis of dihydropyrano[2,3-c]pyrazole derivatives via one-pot multicomponent reaction of aryl aldehyde, malononitrile, ethyl acetoacetate and hydrazine hydrate in water as a solvent. The catalyst is non-toxic in nature, commercially available, biodegradable and easily separated from the reaction mixture. Present protocol avoids the use of the heavy metal catalyst, harsh reaction condition and the reusability of catalyst, broad substrate scope, simple work-up procedure and excellent yield of products make this protocol greener. KEY WORDS: Pyrano[2,3-c]pyrazole, Sodium gluconate, Multicomponent reaction (MCR), Knovenagel condensation, Bio-based organocatalyst Bull. Chem. Soc. Ethiop. 2019, 33(2), 331-340.DOI: https://dx.doi.org/10.4314/bcse.v33i2.1