Chitosan supported ionic liquid (CSIL): An excellent catalyst for one-pot synthesis of bis(indolyl)methanes

In this present communication, one-pot synthesis of bis(indolyl)methane derivatives (3a-t) achieved from the condensation of indole (1) with various substituted benzaldehydes (2a-t) using [DSIM][AlCl3]x-@CS chitosan supported ionic liquid (CSIL) as catalyst in ethanol at mild reaction was reported. The main advantage of this present methodology using chitosan supported ionic liquid was leads to effective formation of products were achieved under optimized condition without an inert atmosphere. In addition to this, shorter reaction time, simple work-up procedure, easy preparation of the catalyst and chemoselectivity were significantly noted. Further, the newly synthesized compounds were fully characterized by the spectroscopic methods.