Bismuth triflate catalyzed condensation of δ-hydroxy-α,β-unsaturated aldehydes with aryl amines

α,β-Unsaturated aldehydes bearing a δ-hydroxyl group undergo a tandem Michael and intramolecular Friedel–Crafts type cyclization with arylamines in the presence of 5 mol % of Bi(OTf)3 under mild conditions to afford a new class of chiral tetrahydroquinolines in good yields with high stereoselectivity. Structural assignments and the stereochemistry of the products was achieved using various 1D and 2D-NMR experiments.