Fe3O4@THAM-piperazine: a novel and highly reusable nanocatalyst for one-pot synthesis of 1,8-dioxo-octahydro-xanthenes and benzopyrans

Recent trends in synthetic strategies using magnetic nanostructures as green catalysts in synthesis of pyran analogues

“…Hazeri and his group [69] designed a novel magnetically heterogeneous nanocatalyst by immobilization of piperazine on tris (hydroxymethyl)aminomethanecovered Fe 3 O 4 magnetic nanoparticles (Fe 3 O 4 @THAMpiperazine) (Figure 3) for one-pot synthesis of derivatives of tetrahydrobenzo[b]pyran and 1,8-dioxo-octahydro- Noteworthy features of this user-friendly catalytic system integrated viz; extreme catalytic activity, easy operation, non-toxicity, and quick workup. Also, nanocatalysts could be easily retrieved and reused six times without losing their effectiveness.…”

“…Hazeri and his group [ 69 ] designed a novel magnetically heterogeneous nanocatalyst by immobilization of piperazine on tris (hydroxymethyl)aminomethane‐covered Fe 3 O 4 magnetic nanoparticles (Fe 3 O 4 @THAM‐piperazine) ( Figure 3 ) for one‐pot synthesis of derivatives of tetrahydrobenzo[ b ]pyran and 1,8‐dioxo‐octahydro‐xanthene through a reaction of dimedone, aldehydes with of dimedone or malononitrile using H 2 O: EtOH (1:1) as a solvent system at 100 °C ( Scheme 25 ) . Noteworthy features of this user‐friendly catalytic system integrated viz; extreme catalytic activity, easy operation, non‐toxicity, and quick workup.…”

[Ch][TAPSO] As an Efficient Ionic Liquid Catalyst for One‐Pot Synthesis ofTetrahydro‐4H‐chromenes and 3,4‐Dihydropyrano[c]chromenes

“…[21][22][23] Therefore, the synthesis of tetrahydro-4H-chromenes and 3,4-dihydropyrano[c]chromenes compounds have received considerable interest among the researchers. A number of synthetic methods for tetrahydro-4H-chromenes have been developed so far employing metal catalyst, [24,25] organocatalyst, [26][27][28][29][30] immobilized heterogenous catalyst, [31] magnetic nanocatalyst, [32][33][34][35][36] ionic liquids, [37] and nanostructured molten salt [38] etc. The synthesis of 3,4-dihydropyrano[c] chromene derivatives have also been reported by using various catalysts such as organocatalyst, [39] magnetic nanocatalyst, [40,41] ionic liquids, [42,43] and metal catalyst.…”

Application of salicylic acid as an eco‐friendly and efficient catalyst for the synthesis of 2,4,6‐triaryl pyridine, 2‐amino‐3‐cyanopyridine, and polyhydroquinoline derivatives

“…[ 2 ] Hence, most investigations have focused on the design of synthetic strategies containing environmentally friendly conditions such as using a green catalyst, low temperature, using the green solvents or solvent‐free condition. [ 3–7 ]…”