Periodic Mesoporous Organosilica Containing Bridged N‐Sulfonic Acid Groups: Promotion of the Synthesis of N,N’‐Diarylformamidines, Benzoxazoles, Benzothiazoles and Benzimidazoles

Abstract 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.