Silica sulfuric acid as an inexpensive and recyclable solid acid catalyzed efficient synthesis of quinolines

Silica sulfuric acid as an inexpensive and recyclable solid acid efficiently catalyzes the Fridedlander synthesis of quinolines through a condensation reaction of a 2-aminoaryl ketone with an activated alpha-CH acid compound under solvent-free conditions in high yields at 100 degrees C.