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Herein, we report a green, sustainable, and metal‐free, one‐pot three‐component protocol for the synthesis of indeno [1, 2‐b] quinoxalin‐11‐ylidenamine derivatives using a novel, effective, and recyclable mesoporous heterogeneous organocatalyst [MTP−IL]. [MTP−IL] was constructed by immobilizing an imidazolium‐cation‐based ionic liquid on a melamine−terephthalaldehyde covalent organic polymer and was thoroughly characterized using several analytical techniques. It displayed high thermochemical stability and catalytic efficacy, offering title compounds with 90–94 % yields in a short reaction time, and was recyclable for up to six cycles. The synthesized compounds were characterized through FTIR, 1H, and 13C Nuclear Magnetic Resonance (NMR), and the molecular structure of N′‐(11H‐indeno[1,2‐b]quinoxalin‐11‐ylidene)benzohydrazide (7) was confirmed by the Single Crystal XRD (SCXRD) analysis. The key features of the present protocol are the use of ethanol as a green solvent, easy catalyst recovery, a simple work‐up procedure, and zero involvement of any metal. [ABSTRACT FROM AUTHOR]

A novel series of heteropoly ionic liquids [HMIm]3[PW12O40], [HMIm]3[PMo12O40], and [HMIm]4[SiW12O40] were synthesized and supported on magnetic γ-Fe2O3 NPs to get magnetic heterogeneous catalysts, Fe2O3-[HMIm]3[PW12O40], Fe2O3-[HMIm]3[PMo12O40], and Fe2O3-[HMIm]4[SiW12O40]. The materials were characterized using various techniques such as FTIR, EDX, XRD, TEM, SEM, elemental mapping, EPR, TGA, and VSM analyses. Among the three heteropoly ionic liquids, [HMIm]3[PW12O40] had very strong acidic sites, as confirmed by potentiometric titration. Fe2O3-[HMIm]3[PW12O40] had also very strong acidic property as analyzed by potentiometric titration. Further, thermal stability of Fe2O3-[HMIm]3[PW12O40] was assessed using TGA analysis, and the catalyst was found stable up to 500 °C. The catalytic prospect of the materials was examined through selective oxidation of benzyl alcohol to benzaldehyde using H2O2 as a green oxidant. The reaction was monitored using GC–MS analysis. Among the three magnetic materials, Fe2O3-[HMIm]3[PW12O40] had the highest catalytic activity in terms of conversion of benzyl alcohol (98%) and benzaldehyde selectivity (100%). A recyclability study of Fe2O3-[HMIm]3[PW12O40] was done and found that the material was recyclable up to 7 cycles without any significant loss in its catalytic performance. [ABSTRACT FROM AUTHOR]

The present study used silica functionalized bovine serum albumin as a bio‐support for γ‐Fe2O3 nanoparticles (NPs) to synthesize a magnetically recoverable heterogeneous catalyst (BSA‐Si@Fe2O3). The structure of the catalyst was well established by various techniques such as Fourier transform infrared (FT‐IR) spectroscopy, Scanning Electron Microscope/Energy Dispersive X‐ray (SEM/EDX), elemental mapping, Transmission Electron Microscope (TEM), Thermogravimetric (TG), Powder X‐ray diffraction (XRD), X‐ray Photoelectron Spectroscopy (XPS), Brunauer–Emmett–Teller (BET), and Electron Paramagnetic Resonance (EPR) analyses. The catalyst also possesses magnetic properties as shown by Vibrating Sample Magnetometer (VSM). The strong acidic properties of the catalyst was calculated using potentiometric titration showing Ei value in the range of 0 < Ei < 100 mV. The catalyst was found to be highly efficient for the synthesis of pyrroles affording high yield (87%–94%) in short reaction time period under environmentally feasible reaction conditions (high atom economy and low E‐factor). The BSA‐Si@Fe2O3 could be recycled up to six cycles with insignificant loss in catalytic potential. [ABSTRACT FROM AUTHOR]