Aqua one-pot, three-component synthesis of dihydropyrano[3,2-c]chromenes and amino-benzochromenes catalyzed by sodium malonate

Ag3[PMo12O40]: An efficient and green catalyst for the synthesis of highly functionalized pyran‐annulated heterocycles via multicomponent reaction

“…To reveal the advantages of this catalyst, its catalytic activity in the model reaction involving benzaldehyde, malononitrile and 4‐hydroxycoumarin was compared with those of previously reported systems (Table ). As evident from Table , the catalytic activity of Ag 3 PMo 12 O 40 was compared with other catalysts such as [DMAP‐PEG 1000 ‐DI L][BF 4 ], nano‐ZnO, crown ether complex cation ionic liquids (CECILs), ammonium acetate, titanium dioxide nanowires, nanomagnetic double‐charged diazoniabicyclo[2.2.2]octane dichloride silica hybrid (Fe 3 O 4 @SiO 2 /DABCO), surfactant‐modified bentonite (CTMAB‐bentonite), hexamethylenetetramine, SiO 2 /H 3 PW 12 O 40 nanohybrid, RuBr 2 (PPh 3 ) 4 , sodium malonate, NaCl, (NH 4 ) 42 [MoVI 72 MoV 60 O 372 (CH 3 COO) 30 (H 2 O) 72 ], a Keplerate‐type giant‐ball nanoporous isopolyoxomolybdate, silica‐supported molybdic acid, KNaC 4 H 4 O 6 ⋅4H 2 O (potassium sodium tartrate) and polypyrrole/Fe 3 O 4 /CNT that were previously used as catalysts in the same reaction. The results showed that compared to the other catalysts, our designed catalyst can catalyse the reaction in an appropriate manner.…”

Design, preparation, and characterization of Fe3O4 nanoparticles encapsulating β‐cyclodextrin‐bearing guanidine as a highly efficient and reusable heterogeneous base catalyst for synthesis of 3,4‐dihydropyrano[3,2‐c]chromenes

“…Therefore, the development of efficient methods for the synthesis of these important heterocycles has attracted researchers' attention. Various methods have been reported for the synthesis of these compounds in the presence of a variety of catalysts, such as thiourea dioxide, [13] DABCO, [14] DBU (1,8-Diazabicyclo[5.4.0]undec-7-ene), [15] dehydroabietylamine-cinchonine-squaramide, [12] magnetic nanoparticles tag: piperidinium benzene-1,-3-disulfonate ionic liquid, [16] polypyrrole/Fe 3 O 4 /Carbon nanotube (CNT), [17] ammonium acetate, [18] Ni(II)functionalized Li + -montmorillonite, [19] sodium benzenesulfinates, [20] sodium malonate, [21] nano-SiO 2, [22] o-benzene disulfonimide, [23] potassium phthalimide, [24] crown ether complex cation ionic liquids, [25] and N,N-dimethylbenzylamine. [26] Cyclodextrins (CDs) are cyclic oligomers made up of α-(1,4)-linked D-glucopyranose units.…”

A one‐pot green synthesis of 2‐amino‐4H‐benzo[h]chromenes catalyzed by a dioxomolybdenum Schiff base complex supported on magnetic nanoparticles as an efficient and recyclable nanocatalyst

“…Hence, the use of green solvents and heterogeneous reusable catalysts with economical, eco‐friendly, and efficient method represents one of the more powerful green chemical technology procedures. Hence, much effort has been devoted to the synthesis of 4 H ‐chromenes using different catalytic systems …”

“…Hence, much effort has been devoted to the synthesis of 4H-chromenes using different catalytic systems. [17][18][19][20][21][22][23] Because heterogeneous catalysts could be separated easily and reused, much attention is focused on development of these types of catalysts. [24] There has already been a vast literature about the usage of many supports for the heterogenization of homogeneous catalysts, such as organic polymers, [25] mesoporous silica, [26] and carbon-based compounds such as graphene oxide, [27] zeolites, [28] and so on.…”