Protic pyridinium ionic liquid as a green and highly efficient catalyst for the synthesis of polyhydroquinoline derivatives via Hantzsch condensation in water

► [2-MPyH]OTf catalyzed one-pot synthesis of polyhydroquinoline derivatives in water. ► This method was the mild reaction conditions. ► This reaction was the requirement lower catalytic. ► This method has the ability to tolerate a wide variety of substitutions. ► This method has the high yield and the shorter reaction times.