Sustainable synthesis of azobenzenes, quinolines and quinoxalines viaoxidative dehydrogenative couplings catalysed by reusable transition metal oxide–Bi(iii) cooperative catalystsElectronic supplementary information (ESI) available: Quantitative analysis of the as-prepared catalysts, optimization procedure for the synthesis of azobenzene, selectivity tests of the CoBi2O2CO3, supporting tests for the catalytic quinoxaline synthesis, comparative tables with the catalytic performance of benchmark catalysts, XRD patterns of the CoBi2O2CO3used, NMR data of the products. See DOI: https://doi.org/10.1039/d3cy00327b

Oxidative dehydrogenative coupling (ODC) is a useful tool for the formation of new C–C, C–O and NN bonds in an atom-economic and sustainable manner. Although this strategy is versatile, it is much less introduced to prepare N-heterocycles. Herein, we report the oxidative dehydrogenative coupling of anilines and 2-aminoanilies with vicinal diols to selectively produce azobenzenes (34–95% yield), quinolines (65–100% yield) and quinoxalines (78–100% yield) utilizing an environmentally friendly synthesis strategy. The reactions were catalysed by cooperative bifunctional catalysts based on transition metal oxides/Bi(iii) which allow solvent-, additive-, oxidant- and base-free cyclisations/couplings. In addition, the catalysts were proven to be highly robust and reusable.