Three-component reactions of nitroarenes, aldehydes, and phenylacetylene in the presence of indium in dilute hydrochloric acid produce the corresponding quinoline derivatives under reflux. The conversion in this one-potsynthesis involves the following steps: (i) reduction of the nitroarenes to anilines, (ii) coupling of the anilines, aldehydes, and phenylacetylene, (iii) cyclization of the resulting