Rh-catalysed direct cyclisation of 1,4-naphthoquinone and 9,10-phenanthraquinone with alkyne: facile access to 1,8-dioxapyrenes and 1,12-dioxaperylenes as orange and red-emitting luminophores

Rh-catalysed direct cyclisation of 1,4-naphthoquinones and 9,10-phenanthraquinones with alkynes has been accomplished for the first time through the C–H activation strategy to forge 1,8-dioxapyrenes and 1,12-dioxaperylenes. Starting from readily available substrates, a variety of dipyran-containing PAHs are obtained in one step and exhibit orange/red-emitting performance, large Stokes shifts and high thermal stability.