Synthesis of polysubstituted 1,2-dihydroquinolines and indoles via cascade reactions of arylamines and propargylic alcohols catalyzed by FeCl3·6H2O.

An efficient, environmentally friendly and high-yielding route from inexpensive starting materials to 1,2-dihydroquinolines has been developed. This procedure proceeded via a cascade Friedel-Crafts-type reaction and 6-endo-trig hydroamination under the catalysis of FeCl3·6H2O, involving the formation of two new σ (C-C and C-N) bonds in a single operation for the construction of a 1,2-dihydroquinoline skeleton in good to excellent yields.