Covalently bonded zwitterionic sulfamic acid onto the SBA-15 (SBA-15/PrEn-NHSO3H) reveals good Bronsted acidity behavior and catalytic activity in N-formylation of amines

Abstract

Ethylenediamine-functionalization of SBA-15 with N1-(3-(trimethoxysilyl)propyl)ethane-1,2-diamine (PrEn) was then underwent covalent sulfonation over secondary and primary amine groups (SBA-15/PrEn-NHSO3H) on the surface of the mesoporous SBA-15 pore walls. Scanning electron microscope (SEM), transmission electron microscope (TEM), SEM-energy dispersive X-ray (SEM-EDX), BET surface are analysis, thermal gravimetric (TG), FT-IR spectrums and CHNS were recorded for the characterization of SBA-15/PrEn-NHSO3H. This material was studied as a novel catalyst for N-formylation of amines. Based on the results, SBA-15/PrEn-NHSO3H acted as zwitterionic IL-type heterogeneous catalyst with simple separation feature from the reaction mixture. Moreover, it exhibited excellent recyclability at least for 12 times, and a higher catalytic activity toward N-formylation.