Ultrasound assisted N-bromosuccinimde catalyzed one pot condensation approach for synthesis of Bis(indolyl)methanes from primary alcohols

A simple, efficient protocol for one pot synthesis of bis(indolyl)methanes from primary alcohols is investigated with N-bromosuccinimde as a catalyst under ultrasound irradiation. Alcohols can be converted into carbonyl compounds by removal of hydrogen in presence of N-bromosuccinimde as an oxidant and can react in situ with indole to give desired bis(indolyl)methanes. In the reported one pot multicomponent condensation reaction N-bromosuccinimde promotes the oxidation of alcohol to aldehyde, facilitating the subsequent condensation with indole to afford bis(indolyl) methanes in good to excellent yields. The inexpensiveness and easy handling are some of important feature of N-bromosuccinimde. The by-product N-succinimide can be easily recovered and recycled to N-bromosuccinimide.