Introduction of a novel Brønsted acidic ionic liquid for the promotion of the synthesis of quinolines

3,3′-(Butane-1,4-diyl) bis (1-methyl-1H-imidazol-3-ium)·dibromide·disulfuric acid (C4(mim)2-2Br 18 Q4 −-2H2SO4)as a new ionic liquid was prepared and efficiently used for the promotion of the one-pot synthesis of quinoline polycyclic compounds via the condensation of 2-aminoaryl ketones and β-ketoesters/ketones. All reactions are performed in the absence of solvent in high to excellent yields during short reaction times

Ionic liquid, Reusable catalyst, Quinolines, Friedländer synthesis, Solvent-free conditions