Green One‑Pot Photocatalytic Synthesis of Quinolines Using a CuO/TiO ₂ Nanocomposite Under Visible Light

The synthesis of 2‐ or 2,3‐substituted quinolines was carried out using nitrobenzaldehyde and methyl ketones using visible light induced by copper oxide‐titanium dioxide nanocomposites (CuO/TiO 2 NC) and CuI and isopropanol as cocatalysts to activate the starting material and reduce the nitro group. The synthesis of quinolines via visible light reduction of the ortho‐nitrochalcone intermediate formed in situ by direct photoexcitation using copper iodide and isopropanol as a green and renewable hydrogen source at room temperature has been developed. CuO/TiO 2 NC is a stable photocatalyst and can be reused several times without losing its catalytic properties. The eco‐friendly, cost‐effective method, and easy isolation along with high product yields are the advantages of this method. All synthesized quinolines were characterized using NMR spectroscopy.