Montmorillonite K10: An Efficient Organo-Heterogeneous Catalyst for Synthesis of Benzimidazole Derivatives

Abstract

The use of toxic solvents, high energy consumption, the production of waste and the application of traditional processes that do not follow the principles of green chemistry are problems for the pharmaceutical industry. The organic synthesis of chemical structures that represent the starting point for obtaining active pharmacological compounds, such as benzimidazole derivatives, has become a focal point in chemistry. Benzimidazole derivatives have found very strong applications in medicine. Their synthesis is often based on methods that are not convenient and not very respectful of the environment. A simple montmorillonite K10 (MK10) catalyzed method for the synthesis of benzimidazole derivatives has been developed. The use of MK10 for heterogeneous catalysis provides various advantages: the reaction yields are decidedly high, the work-up procedures of the reaction are easy and suitable, there is an increase in selectivity and the possibility of recycling the catalyst without waste formation is demonstrated. The reactions were carried out in solvent-free conditions and in a short reaction time using inexpensive and environmentally friendly heterogeneous catalysis. It has been shown that the reaction process is applicable in the industrial field.

In situ preparation of a ferric polymeric aluminum chloride–silica gel nanocatalyst by mechanical grinding and its solid-phase catalytic behavior in organic synthesis

“…Four classes of nitrogen-containing compounds such as 3alkylindole derivatives, 21,22 quinoxaline derivatives, 23,24 benzimidazole derivatives, 25,26 and b-amino alcohol derivatives 27,28 are widely used in the synthesis of pharmaceutical intermediates. The research on the green and efficient synthesis of these products from simple chemical raw materials has great practical value, and the use of mechanochemical methods to produce the above compounds will greatly reduce the generation of toxic waste during the production process.…”

Clay based heterogeneous catalysts for carbon–nitrogen bond formation: a review

“…Bonacci et al 111 addressed a procedure for the preparation of benzimidazole derivatives using a montmorillonite K10 heterogeneous catalyst. Benzimidazole has numerous biological applications, and the earlier method of synthesis of the compound has some drawbacks.…”

An Iminostilbene Functionalized Benzimidazoline for Enhanced n‐Type Solution Doping of Semiconducting Polymers for Organic Thermoelectrics

“…This procedure was inspired by the protocol devised by Bonacci et al to prepare a benzimidazoline derivative. [36] The starting diamine (2) was obtained following a procedure previously reported by our group, while the aldehyde (1) was synthesized adapting a palladium catalyzed Buchwald-Hartwig amination reaction. [22,37] The condensation reaction was performed under inert atmosphere using Montmorillonite clay (MM-K10) as heterogeneous acid catalyst, and the product was isolated by dry-flash chromatography performed in the dark.…”