Tandem Electro-Oxidative C-C and C-N Coupling and Aromatization for the Construction of Pyrazine-Fused Bis - aza[7]helicene.

Repeated tandem electro-oxidative C-C and C-N coupling and aromatization were employed for the efficient construction of aza[7]helicene ( BA7 ) as a key intermediate and the targeted pyrazine-fused bis - aza[7]helicene ( PBBA7 ) derivatives in 90.0-93.2% isolated yields under a controlled potential. The electrosynthetic protocol showed high selectivity and enabled rapid access to functionalized organic conjugated materials from readily available polycyclic aromatic amines. A synthetic mechanistic study along with an investigation of the photoelectrical properties and application of PBBA7-C16 as a potential hole-transporting material for perovskite solar cells were performed.