Potassium sodium tartrate as a versatile and efficient catalyst for the one-pot synthesis of pyran annulated heterocyclic compounds in aqueous media

Efficient tandem synthesis of a variety of pyran-annulated heterocycles, 3,4-disubstituted isoxazol-5(4H)-ones, and α,β-unsaturated nitriles catalyzed by potassium hydrogen phthalate in water

“…Several synthetic methods have been widely applied for synthesis of pyran-based heterocyclic compounds, using many homogeneous or heterogeneous organic, inorganic, and nanomaterial catalysts, for example hexamethylenetetramine (HMT) [40], heteropolyacid [41], diammonium hydrogen phosphate [42], DBU [43], piperidine [44][45][46][47], tetrabutylammonium bromide (TBAB) [48], ionic liquids [49], morpholine [50], 4-(dimethylamino)pyridine (DMAP) [51], urea [52], 3-hydroxypropanaminium acetate (HPAA) [53], N-propylpiperazine sodium n-propionate (SBPPSP) [54], silica gel [55], sulfonic acid-functionalized silica [ [60], meglumine [61], I 2 /K 2 CO 3 [62], cetyltrimethylammonium bromide (CTABr) [63], nano-sized MgO [64], nano-structured Na 2 CaP 2 O 7 [65], NaHCO 3 [66], Na 2 CO 3 [67], triazine-functionalized ordered mesoporous organosilica [68], potassium phosphate tribasic trihydrate [69], Mg/Al hydrotalcite [70], Amberlyst A21 [71], DABCO [72], CeO 2 /CaO nanocomposite oxide [73], triton B [74], tetrabutylammonium chloride (TBAC) [75], nano-eggshell powder [76], basic alumina [77], [bmim]OH [78,79], LiBr [80], glycine [81], silica nanoparticles [82], ionic liquid choline chlorid...…”

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.…”

Zr@IL-Fe3O4 MNPs as an efficient and green heterogeneous magnetic nanocatalyst for the one-pot three-component synthesis of highly substituted pyran derivatives under solvent-free conditions

“… 38 Also, 4 H- benzo-[ b ]-pyrans are other derivatives of heterocycles with a common structural motif in a diversity of natural and synthetic products. The acceleration of the synthesis of these compounds via the condensation reactions of dimedone, malononitrile, and aldehyde has been accomplished using numerous homogeneous or heterogeneous catalysts; for example, [DMImd-DMP], 39 KNaC 4 H 4 O 6 ·4H 2 O, 40 K 2 CO 3 /cyanuric acid, 41 nano-kaoline/BF 3 /Fe 3 O 4 , 42 TMGT, 43 and [γ-Fe 2 O 3 @Hap-Si-(CH 2 ) 3 -AMP]. 44 Even though most of these methods offer distinct advantages, some of them have one or more limitations, such as low yields of the desired product, generation of a large amount of waste, long reaction times, poor recovery of the catalyst, and hard reaction conditions.…”