Synthesis of polycyclic quinolines using SiO2/H2SO4 via Friedlӓnder synthetic method

Graphical Abstract Abstract An attention to the novel synthetic route for the polycyclic quinolines ( 3 & 5 ) from cyclic-diketones, with o-aminoarylketones ( 1 ) in the presence of SiO 2 /H 2 SO 4 yielded via Friedlӓnder synthetic method. The catalytic efficiency of the SiO 2 /H 2 SO 4 was discussed through their utilization in the synthesis of biologically active substituted polycyclic quinoline derivatives ( 3 & 5 ) and the mechanism has been proposed. The SiO 2 /H 2 SO 4 was found as a effective catalyst for the Friedlӓnder reaction and gave considerable isolated yield of the targeted products under the mild reaction condition. The synthesized polycyclic quinolines ( 3 & 5 ) were characterized through diverse analytical techniques like FT-IR, NMR spectroscopy and single crystal X-ray diffraction studies.