AB rønsted-acidic ionic liquid gel was prepared from 1-(4-sulfonic acid)butyl-3-methylimidazolium hydrogen sulfate and tetraethoxysilane. Its structural characterization was accomplished by FTIR, TGA, SEM, EDS, and ICP-OES. The ionic liquid gel promotes the synthesis of bis(indolyl)methanes. Interestingly,t his catalyst allowst he preparation of bis(indolyl)methanes in good to excellenty ields within a short reaction time, through ac lean and straightforward procedure. Moreover,t he ionic liquid gel can be recovered by filtration and can be reused up to 5t imes without any detectable loss of catalytic performance. Additionally,t he methodh as aw ide substrate scope and provides an accessible route for the large-scale direct synthesis of bis(indolyl)-methanes.

A green and efficient method for Paal–Knorr pyrrole synthesis has been developed under mild conditions.

A novel magnetically separable catalyst can be used as a green solid Lewis acid catalyst in the synthesis of benzoxanthenes and pyrroles under solvent-free sonication.

Metal‐triflate‐catalyzed intramolecular Friedel–Crafts acylation of 3‐arylpropanoic and 4‐arylbutanoic acids in triflate‐anion ionic liquids under monomodal microwave irradiation is reported. The environmentally benign synthetic procedure allows the formation of cyclic ketones in good yields within a short reaction time. The catalytic metal triflate in triflate‐anion ionic liquids can be easily recovered and reused several times without significant loss of the catalytic performance.