n-Dodecylbenzene Sulfonic Acid (DBSA) as a Novel Brønsted Acid Catalyst for the Synthesis of Bis(indolyl)methanes and Bis(4-hydroxycoumarin-3-yl)methanes in Water

Copyright © 2013 Balu Pawar et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. n-Dodecylbenzene sulfonic acid (DBSA) as a novel, biodegradable, and efficient Brønsted acid catalyst used for the reaction of indoles/4-hydroxy coumarin with aldehydes to obtain a bis(indolyl)methanes/bis(4-hydroxycoumarin-3-yl)methanes, respectively. The catalyst exhibited remarkable activity, and tolerated a wide variety of functional groups providing the desired bis(indolyl)methanes and bis(4-hydroxycoumarin-3-yl)methanes in good to excellent yield (70 %-96%) in water