Dehydrogenation of Nitrogen Heterocycles Using Graphene Oxide as a Versatile Metal-Free Catalyst under Air

Graphene oxide (GO) has been developed as an inexpensive, environmental friendly, metal-free carbocatalyst for the dehydrogenation of nitrogen heterocycles. Valuable compounds, such as quinoline, 3,4-dihydroisoquinoline, quinazoline, and indole derivatives, have been successfully used as substrates. The investigation of various oxygen-containing molecules with different conjugated systems indicated that both the oxygen-containing groups and large p-conjugated system in GO sheets are essential for this reaction.