Synthesis of novel pyrrole derivatives from the multicomponent reaction using the new N-sulfonic acid modified poly (styrene-diethylenetriamine) as a solid acid catalyst

An efficient acid-catalyzed synthesis of 1,5-diaryl-3-(arylamino)-1H-pyrrol-2(5H)-ones is reported using novel N-sulfonic acid modified poly (styrene-diethylenetriamine) through three-component reaction between aldehyde, amine, and ethyl pyruvate in high yields and short times. This heterogeneous solid catalyst is produced by reacting amine-modified chloromethyl polystyrene with neat chlorosulfonic acid. The structure of the synthesized catalyst was examined with Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction (XRD), dynamic light scattering (DLS), thermogravimetric analysis (TGA), differential thermal analysis (DTA), scanning electron micrograph (SEM), Brunauer–Emmett–Teller (BET), energy dispersive spectroscopy (EDS), and elemental analyses. The heterogeneous catalyst has many advantages, including an easy work-up procedure, a high product yield, and the capability to be easily regenerated and reused for at least five cycles without losing its activity.