Ultrasound promoted and SiO2/CCl3COOH mediated synthesis of 2-aryl-1-arylmethyl-1H-benzimidazole derivatives in aqueous media: An eco-friendly approach

Water compatible silica supported iron trifluoroacetate and trichloroacetate: as prominent and recyclable Lewis acid catalysts for solvent-free green synthesis of hexahydroquinoline-3-carboxamides

Silica supported iron trifluoroacetate and iron trichloroacetate green Lewis acid catalysts were developed by a novel, cheap, environment-friendly approach and utilized in the synthesis of hexahydroquinoline-3-carboxamide derivatives. The structure and morphology of the prepared Lewis acid catalysts were studied by FTIR, PXRD, FE-SEM, HR-TEM, EDX, BET, TGA and NH3-TPD techniques. The present catalysts shows maximum conversion efficiency in hexahydroquinoline-3-carboxamide derivatives synthesis at 70 °C in solvent free reaction condition with best product yield in a short reaction time. Both catalysts are reusable and simple to recover, and perform meritoriously in water as well as in a variety of organic solvents. The key advantages of the current synthetic route are permitting of a variety of functional groups, quick reaction time, high product yield, mild reaction condition, recyclability of catalyst and solvent-free green synthesis. This makes it more convenient, economic and environmentally beneficial.

Silica supported lanthanum trifluoroacetate and trichloroacetate as an efficient and reusable water compatible Lewis acid catalyst for synthesis of 2,4,5-triarylimidazoles via a solvent-free green approach

In the present research article, we have developed solid heterogenous silica supported lanthanum trifluoroacetate and trichloroacetate as green Lewis acid catalysts. These catalysts were synthesized by a novel, simple, cheap, clean, and environment friendly method. The physicochemical properties of the prepared catalysts were well studied and characterized by sophisticated spectroscopic techniques such as FTIR, TGA, XRD, EDX, SEM, TEM and BET analysis. The catalyst was utilized in the synthesis of arylimidazole derivatives via green protocols under solvent-free conditions at 70 °C with a higher yield, mild reaction conditions and a short reaction time. The catalyst works superiorly in water as well as in various organic solvents as a reusable and easily recoverable catalyst.

Green Protocol: Catalyst-Free Synthesis of 2-Substituted Benzimidazoles under Ultrasound Irradiation

The synthesis of 2-substituted benzimidazoles from the reaction of o-phenylenediamine and an imino ester hydrochloride with ultrasound irradiation is reported. The procedure has an eco-friendly and simple workup with good yield in a short time.