124557-95-5Relevant articles and documents
Silica supported sodium hydrogen sulfate (NaHSO4-SiO 2): A novel, green catalyst for synthesis of pyrazole and pyranyl pyridine derivatives under solvent-free condition via heterocyclic β-enaminones
Siddiqui, Zeba N.,Farooq, Farheen
, p. 451 - 459 (2012/10/29)
NaHSO4-SiO2 is used as an efficient, mild and reusable catalyst for the synthesis of novel heterocyclic pyrazole (5a-h) and pyranyl pyridine (7a-h) derivatives via heterocyclic β-enaminones (3a-d) under thermal solvent-free conditions. The remarkable features of this green, new methodology are high conversions, cleaner reaction profile, simple experimental and work-up procedures. Structures of the newly synthesized compounds have been elucidated on the basis of elemental analysis and spectral data (IR, 1H NMR, 13C NMR and mass spectrometry). The catalyst is characterized for the first time by using scanning electron microscopy-energy dispersive X-ray (SEM-EDX) and powder XRD. The catalyst can be reused several times without significant loss of its catalytic activity.