RED MUD CATALYZED ONE-POT SYNTHESIS OF 3-SUBSTITUTED COUMARINES UNDER MICROWAVE IRRADIATION

One-pot synthesis of 3-substituted coumarines using Red mud (RM) which emerges as a by-product from the alumina producing process as catalyst via Knoevenagel condensation of 2- hydroxybenzaldehyde derivatives and malonate derivatives investigated. Reaction carried out undervarious conditions and the best results obtained when the reaction done under microwave irradiation. RM showed an efficient catalytic activity in this reaction. The catalyst can be used for at least four times after reactivation without remarkable losing in its efficiency

Keywords:

3-Substituted coumarines , Red mud , Microwave irradiation , 2-Hydroxybenzaldehyds , Knoevenagel condensation , Malonate ester