One‐Pot Multicomponent Synthesis of Pyrano[2,3 c]pyrazole Derivatives Using CMCSO3H as a Green Catalyst

Abstract

AbstractA promising application of sulfonated carboxymethylcellulose (SCMC) as a green heterogeneous catalyst in the synthesis of pyrano[2,3c]pyrazole derivatives has been studied here. Sulfonated carboxymethyl cellulose was synthesized through a new, green and efficient pathway. The synthesized SCMC catalyst was characterized using Fourier transform infrared (FT‐IR) spectroscopy, energy dispersive X‐ray (EDX) analysis, X‐ray diffraction (XRD) pattern, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Its catalytic ability was then investigated in the pyranopyrazole synthesis. The SCMC as a biopolymer‐derivative solid acid catalyst indicated catalytic activity in the one‐pot multi‐component synthesis of pyrano[2,3c]pyrazole derivatives using the reaction of ethyl acetoacetate, hydrazine hydrate, malononitrile, and various aldehydes in ethanol as a green solvent. The key features of this methodology are operational simplicity, use of a stable, recoverable, and non‐toxic catalyst, simple purification of the product by non‐chromatographic methods, high yields, environment‐friendly reaction, and economically lucrative.