Selective\nCatalytic Hydrogenation of Heteroarenes\nwith <i>N</i>‑Graphene-Modified Cobalt Nanoparticles\n(Co₃O₄–Co/NGr@α-Al₂O₃)

Abstract

Cobalt\noxide/cobalt-based nanoparticles featuring a core–shell\nstructure and nitrogen-doped graphene layers on alumina are obtained\nby pyrolysis of Co­(OAc)₂/phenanthroline. The resulting\ncore–shell material (Co₃O₄–Co/NGr@α-Al₂O₃) was successfully applied in the catalytic hydrogenation\nof a variety of <i>N</i>-heteroarenes including quinolines,\nacridines, benzo­[<i>h</i>], and 1,5-naphthyridine as well\nas unprotected indoles. The peculiar structure of the novel heterogeneous\ncatalyst enables activation of molecular hydrogen at comparably low\ntemperature. Both high activity and selectivity were achieved in these\nhydrogenation processes, to give important building blocks for bioactive\ncompounds as well as the pharmaceutical industry.