Carbon Nanotube–Ruthenium Hybrids for the Partial Reduction of 2‐Nitrochalcones: Easy Access to Quinoline N ‐Oxides

A ruthenium–carbon nanotube nanohybrid was employed as a catalyst in the tandem transformation of nitrochalcones into quinoline N ‐oxides. Partial reduction of the nitro group to a hydroxylamine, followed by in situ intramolecular condensation to the carbonyl afforded the quinoline‐ N ‐oxides in satisfactory to good yields. Reduction of the nitro group was selective and independent of changes in the reaction conditions. Highlights of this method include a very low catalyst loading relative to that required for conventional methods for the synthesis of quinoline N ‐oxides and mild reaction conditions.