Synthesis of azahelicene N-oxide by palladium-catalyzed direct C-H annulation of a pendant (Z)-bromovinyl side chain.

Driving benzene round the twist: Azahelicene derivatives were synthesized in high yields by utilizing palladium-catalyzed C-H annulation reactions. Functionalization at the C5 position in 6-azahelicene by using palladium-catalyzed C-H arylation also gave coupling products in good yields. A tandem intra- and intermolecular double C-H coupling reaction was performed to give a functionalized helicene in a one-pot procedure.