Stannous chloride mediated one pot synthesis of functionalized indole-3-yl pyridines using 3-cyanoacetylindoles and 3-formylchromones

An efficient one-pot synthesis of functionalized indole-3-yl pyridines by condensation of 3-formylchromones, cyanoacetylindoles and ammonium acetate has been achieved. A series of 17 new compounds were synthesized and all of them were characterized by FT-IR and NMR. The crystal structure of a typical compound was determined by X-ray diffraction. A variety of substrates can participate in the process resulting in high purity and good yields, making this methodology suitable for library synthesis in drug discovery.