Design, Preparation and Identification a Mesoporous Bi-functional Organic–inorganic Hybrid Magnetic Catalyst for Selective and Effectual Synthesis 10,11-Dihydrochromeno[4,3-b]chromene-6,8(7H,9H)-dione Derivatives

In the current work, N,N′-bipyridyl (N- sulfonic acid) (N′- silica-n-propyl) propane mesylate/chloride bonded to Fe₃O₄ coated with bilayer silica ([BPSSPMCFS]) was used as a novel bi-functional inorganic-organic hybrid magnetic nanocatalyst to manufacture 10,11-dihydrochromeno[4,3-b]chromene-6,8(7H,9H)-diones under solvent-free conditions. The methods of field emission scanning electron microscopy (FE SEM), energy-dispersive X-ray spectroscopy (EDX), elemental mapping, Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) analyses, thermal gravimetric analysis (TGA), vibrating sample magnetometry (VSM) and Brunauer-Emmett-Teller (BET) were used to identify this nanohybrid. The [BPSSPMCFS] produced the mentioned derivatives with great selectivity without producing side products, and besides this important feature, which has always been one of the main problems on the way to the synthesis of these compounds, it has significant advantages such as simple synthesis, the use of green media, large surface area, simple separation and workup, very suitable turnover number (TON) and turnover frequency (TOF) values, great reuse for several consecutive cycles without noticeably changing its catalytic activity, and short reaction time. Moreover, the hot filtration technique was used to examine and confirm the heterogeneous nature of [BPSSPMCFS]. Graphical abstract: [Figure not available: see fulltext.]