Periodic mesoporous organosilica containing bridged N‐sulfonic acid groups : promotion of the synthesis of N,N’‐diarylformamidines, benzoxazoles, benzothiazoles and benzimidazoles

In this study, the successful synthesis of periodic mesoporous organosilica containing bridged N-sulfonic acid groups (SA-PMO) is demonstrated. The formation and morphology of the reagent were confirmed by N-2 adsorption-desorption isotherms and pH measurement, X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared (FT-IR) analysis. After identification, the catalytic activity of this reagent was investigated in the synthesis of N,N'-diarylformamidines, benzoxazoles, benzothiazoles and benzimidazoles. Eco-friendly protocol, excellent yields, short reaction times, ease of preparation, reusability of the catalyst and easy isolation of the products are the main advantages of this protocol. The considerable efficiency of the catalyst can be related to its high surface area, large pore volume and high acidity

Nano Rice Husk Ash Modified with Acidic Ionic Liquid Bridge: An Efficient Promoter for the Synthesis of 1,2,4-Triazolo Quinazolinones

In this study, a new heterogeneous catalyst was obtained easily and simply from the preparation and consolidation of bis-3-(trimethoxysilylpropyl)-ammonium hydrogen sulfate on nano rice husk ash [RHA-[bip]-NH2+ HSO4–]. After identification this reagent using different techniques including FT-IR, XRD, FESEM, TEM, and TGA, its application as an efficient catalyst was investigated in the acceleration of the preparation of 1,2,4-triazolo quinazolinones. All reactions using this catalyst were performed under solvent-free conditions and all products were obtained in suitable times with high isolated yields without the formation of any by-products. Furthermore, the reusability of the catalyst was investigated during successive three runs.</p

Synthesis of tetrahydrobenzo[b]pyran and pyrano[2, 3-d]pyrimidinone derivatives using Fe3O4@Ph-PMO-NaHSO4 as a new magnetically separable nanocatalyst

Immobilized NaHSO4 on core/shell phenylene bridged periodic mesoporous organosilica magnetic nanoparticles (Fe3O4@Ph-PMO-NaHSO4) as a new acidic magnetically separable nanocatalyst was successfully prepared in three steps: (i) preparation of Fe3O4 nanoparticles by a precipitation method, (ii) synthesis of an organic-inorganic periodic mesoporous organosilica structure with phenyl groups on the surface of Fe3O4 magnetic nanoparticles (MNPs) and (iii) finally adsorption of NaHSO4 on periodic mesoporous organosilica (PMO) network. The prepared organic-inorganic magnetic reagent was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), N-2 adsorption-desorption and energy-dispersive X-ray (EDX) techniques. Finally, it was used as a reusable and new catalyst to promote the synthesis of tetrahydrobenzo[b]pyran and pyrano[2,3-d]pyrimidinone derivatives as important biologically active compounds. Eco-friendly protocol, high yields, short reaction times and easy and quick isolation of the products are the main advantages of this procedure

Periodic Mesoporous Organosilica Containing Bridged N

In this study, the successful synthesis of periodic mesoporous organosilica containing bridged N-sulfonic acid groups (SA-PMO) is demonstrated. The formation and morphology of the reagent were confirmed by N-2 adsorption-desorption isotherms and pH measurement, X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared (FT-IR) analysis. After identification, the catalytic activity of this reagent was investigated in the synthesis of N,N'-diarylformamidines, benzoxazoles, benzothiazoles and benzimidazoles. Eco-friendly protocol, excellent yields, short reaction times, ease of preparation, reusability of the catalyst and easy isolation of the products are the main advantages of this protocol. The considerable efficiency of the catalyst can be related to its high surface area, large pore volume and high acidity

Periodic mesoporous organosilica containing bridges with N-sulfonic acid groups : a new catalyst for the efficient formylation of amines and alcohols

In this study, periodic mesoporous organosilica containing bridges withN-sulfonic acid groups (SA-PMO), was easily prepared in two steps: (i) preparation of periodic mesoporous organosilica containing amine-bridges (AM-PMO) via co-condensation of bis[3-(trimethoxysilyl)propyl] amine and tetraethoxysilane and (ii) functionalization of AM-PMO with sulfonic acid. The formation and morphology of the reagent were confirmed by N(2)adsorption-desorption isotherms, pH measurement, X-ray diffraction (XRD), transmission electron microscopy (TEM) and Fourier transform infrared FT-IR analysis. After identification, the catalytic ability of this reagent was investigated in the formylation of amines and alcohols using formic acid. Eco-friendly protocol, excellent yields, short reaction times, reusability of the catalyst and easy and quick isolation of the products are the main advantages of the presented method