Direct reductive coupling of nitroarenes and alcohols catalysed by Co–N–C/CNT@AC

A non-noble heterogeneous catalyst – a Co, N and C composite encapsulated carbon nanotube grown in situ on the surface of activated carbon (Co–N–C/CNT@AC) – was fabricated via the pyrolysis–reduction process. Co–N–C/CNT@AC catalyzed the reductive coupling of structurally diverse nitroarenes and alcohols to imines and secondary amines under exogenous base- and solvent-free conditions. BET, TEM, SEM, XRD and XPS characterization showed that the exceptional catalytic property of Co–N–C/CNT@AC could be explained by its nanostructure, Co–N and basic N species. Our protocol had advantages of low cost, environment-friendliness, and good applicability. Furthermore, a reaction route of nitroarenes, amines and alcohols as the starting materials was proposed to improve the atom economy of the reductive coupling of nitroarenes with alcohols.