Chitosan‐ZnO: An Efficient and Recyclable Polymer Incorporated Hybrid Nanocatalyst to Synthesize Tetrahydrobenzo[b]pyrans and Pyrano[2,3‐d]pyrimidinones under Microwave Expedition

Abstract

The innovation of facile, efficient and mild procedures utilizing contemptible, conveniently separable and reusablesolid catalysts that overcome obstacles are invariably in demand. Hence, a straightforward one-pot multicomponent reaction (MCR) and an expedient procedure for the synthesis of pyran annulated heterocycles 5 a-k and 6 l-v is developed using Chitosan-Zinc oxide (CS-ZnO) hybrid nanocatalyst. Use of aqueous medium is one of the major highlight of the present protocol. This protocol renders ease of operation, facile work up and magnified yields (90-95 %) as well as explores the use of modified polymeric substrates in the organic synthesis.

Cu (Ι) catalyzed A3 cascade coupling via C‐H functionalization followed by cyclization: Synthesis, in silico, in vitro, and toxicity studies of imidazo[2,1‐b]thiazoles

“…Fluconazole was used as the reference compound. [ 36–39 ] Figure 12 illustrates the zone of inhibition owing to the consequence of synthesized compounds on the fungi. Figures 13 and 14 correspond to the graph concerning the comparative antifungal activities of the compounds 7j–x exhibiting different MICs and ZOIs, respectively.…”

“…Fluconazole was used as the reference compound. [36][37][38][39] Figure 12 illustrates the zone of inhibition owing to the consequence of synthesized compounds on the fungi. 6).…”

Fe3O4@nano-almondshell/Si(CH2)3/2-(1-piperazinyl)ethylamine as an effective magnetite almond shell-based nanocatalyst for the synthesis of dihydropyrano[3,2-c]chromene and tetrahydrobenzo[b]pyran derivatives

“…Dihydropyrano[3,2- c ]chromene and tetrahydrobenzo[ b ]pyran are heterocyclic organic compounds containing oxygen and are very attractive. For this reason, so far, many catalysts including ZnO NPs 30 , t-ZrO 2 NPs 31 , SB-DABCO@eosin 32 , Fe 3 O 4 @GO-NH 2 33 , [PEMIM][OH] 34 , [(EMIM)Ac] 35 , L-Proline 36 , Chitosan-ZnO 37 , CESA 38 , Glycine 39 , rGO@Fe 3 O 4 @ZrCp 2 Cl 2 40 , Fe 3 O 4 @ G.tea /Cu 41 , etc. have been used for the synthesis of this class of compounds.…”

Microwave-assisted copper(i) catalyzed A3 cascade coupling of imidazo[1,2-a]pyridines via C–H bond functionalization as selective COX-2 inhibitors and antioxidants, and in silico studies

“…23 Owing to their simplicity, high yield and particularly synthetic feasibility and efficiency, multicomponent reactions (MCRs) have acquired a lot of interest. 24,25 There is continuous widespread interest in the synthesis of imidazopyridines because of the diverse biological properties associated with this system. Many efforts have been developed during the last decade for accomplishing multicomponent reactions using environmentally benign protocols to synthesize these kinds of molecules.…”