Three‐Component One‐Pot Synthesis of 1,4‐Dihydropyrano[2,3‐c]pyrazole Derivatives in Aqueous Media

H14[NaP5W30O110] catalyzed one-pot three-component synthesis of dihydropyrano[2,3-c]pyrazole and pyrano[2,3-d]pyrimidine derivatives

“…We also examined the reaction of 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one with chalcone, but the desired product was not obtained even after prolonged reaction times ( Table 2, entry 13). When 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one was replaced by barbituric acid the related products (III) were obtained in good yields ( Table 2, entries [14][15][16][17][18].…”

“…Moreover, the biological activity of fused azoles has led to intensive research on their synthesis [11][12][13]. Recently, three component one-pot condensation of 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one, aldehydes and malononitrile for the construction of 1,4-dihydropyrano [2,3-c]pyrazole derivatives has been reported under different conditions [14][15][16][17][18]. However, most of the reported methods have their drawbacks.…”

1,10‐Phenanthrolin‐1‐ium Trinitromethanide (1,10‐PHTNM) as a Nano Molten Salt Catalyst With Y‐Aromatic Counter Ion: Applications for Synthesis of Organic Compounds

“…The synthesis of organic compounds include 1,4‐dihydropyrano[2,3‐ c ]pyrazoles, tetrahydrobenzo[ b ]pyran, pyrano[4,3‐ b ]pyrans, bispyrazole, 1 H ‐pyrazolo[3,4‐ b ]quinolones, hexahydroacridine‐1,8‐diones and methylenebis(3‐hydroxy‐5,5‐dimethylcyclohex‐2‐enones) has been considerable attention of organic chemists due to their broad range of pharmaceutical and biological properties include arisugacins, anti‐multidrug‐resistant, anti‐inflammatory, photodynamic therapy, inhibitors of human Chk1 kinase, spasmolytic and anti‐filarial agents . Literature survey shows that various processes and catalysts for the synthesis of these compounds include {[HIM]C(CN) 3 }, {[HMIM]C(CN) 3 },, [nano‐Fe 3 O 4 @SiO 2 @(CH 2 ) 3 ‐Imidazole‐SO 3 H]Cl, 2‐carbamoylhydrazine‐1‐sulfonic acid or carbamoylsulfamic acid, L ‐proline, eggshell (ES)‐supported Cu(OH) 2 nanoribbons, triethylbenzylammonium chloride, [2‐MPyH]OTf, ZnCl 2 , hexadecyltrimethylammonium bromide, phosphomolybdic acid and sodium acetate trihydrate urea …”

Applications of a novel nano magnetic catalyst in the synthesis of 1,8-dioxo-octahydroxanthene and dihydropyrano[2,3-c]pyrazole derivatives

“…The first method has been reported by using the base-catalyzed cyclization of 4-aryliden-5-pyrazolone [32]. New approaches for the production of pyrazole include synthesis based process of β-cyclodextrin [33], cinchona alkaloid derivatives [34], Sc(OTf) 3 [35], triethylamine [36], water or ethanol media [37,38], imidazole [39], CuO/ZrO 2 [40] and triethylbenzylammonium chloride [41].…”