Catalytic efficiency of β-cyclodextrin hydrate-chemoselective reaction of indoles with aldehydes in aqueous medium

The catalytic efficiency of beta-cyclodextrin hydrate has been investigated towards the eco-compatible synthesis of bis-(indolyl)methanes in aqueous medium by the chemoselective reaction of indoles with differently substituted aryl and alkyl aldehydes under mild reaction conditions. The catalytic attributes of beta-cyclodextrin hydrate were also demonstrated through molecular docking and DFT studies. Reactions were slower in D2O than in H2O. Aryl and alkyl ketones remained unaffected under the present condition. Excellent chemoselectivity has been established through intermolecular as well as intramolecular competition experiments. Calculation of Green Chemistry Metrices showed high atom economy and small E-factor for the reaction. (C) 2020 Elsevier Ltd. All rights reserved.