[01] Rohit Gupta, Department of Chemical Sciences, Indian Institute of Science Education and Research-Kolkata (IISER-K), Mohanpur, Nadia,West Bengal, India. [02] Savita Ladage, Department of Chemistry, Homi Bhabha Centre for Science Education, Tata Institute of Fundamental Research, Mumbai, Maharashtra, India. [03] Lakshmy Ravishankar, Department of Chemistry, KET’s V.G. Vaze College of Arts, Science & Commerce, Mulund (East), Mumbai, Maharashtra, India.

An environment friendly synthesis of 2-amino-3-cyano-4-aryl-7,7-dimethyl-5-oxo-4H-5,6,7,8-tetra¬hydrobenzo[b]pyran, 2- aryl benzimidazole and 2-aryl-4,5-dihydro-1H-imidazole derivatives using Mg-Al hydrotalcite as an efficient catalyst has been developed. The excellent efficiency of the catalyst can be attributed to its Lewis acidic sites which resulted in higher reaction yields for different substituted benzaldehydes and shorter reaction time compared to conventional synthetic procedures. An added advantage is reusability of the catalyst, which demonstrates consistent activity over significant number of cyclesafter filtration and washing with ethanol.

Multicomponent Reactions, Green Reactions, Mg-Al Hydrotalcite, Pyrans, Benzimidazole, Imidazole, Lewis Acid

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