EcoScale MCR sustainability to impart rapid access to pyrrolo[1,2-b]pyrazoles scaffolds assisted by recyclable HClO4•SiO2 heterogeneous catalytic system

Abstract

Present work elicits an account of synthesizing a new series of pyrrolo[1,2-b]pyrazole scaffolds involving multi component reaction (MCR) strategy, assisted by silica-supported perchloric acid HClO4ꞏSiO2 as the heterogeneous catalyst. It embraces methyl 2-cyano-2-(phenyldiazenyl)acetate as the key precursor. The reusability of the catalyst up to five synthetic cycles is the value-added advantage of the protocol. Moreover, feasibility of the strategy has been endorsed on the basis of EcoScale values in the sustainable limits. Structural corroboration of all the newly synthesized compounds and catalyst have been ascertained by different spectro analytical data viz., IR, 1H NMR, mass, XRD, TG/DTA and FE-SEM.