One-Pot Synthesis of Quinoline Derivatives Directly from Terminal Alkynes via Sequential Ruthenium(II) and Acid Catalysis

A convenient one-pot synthesis of, 2,3-disubstituted, 2,3,6-trisubstituted. and 2,3,6,7-tetrasubstituted quinoline analogues from terminal alkynes via sequential ruthenium(II) and para-toluenesulfonic acid (p-TSA) co-catalyzed reactions is described The catalytic process is shown to take place first via intermediate formation of an allyl ketone and then addition of an aniline derivative to the allyl ketone The p-TSA is a catalyst for both allyl ketone and quinoline synthetic steps The method allowed us to synthesize a wide range of quinoline derivatives and introduce different substituents by employing various simple starting materials. The reaction allows the synthesis of halogen-containing, products.