Palladium-Catalyzed Double N -Arylation to Access Unsymmetric N , N '-Bicarbazole Scaffolds.

Herein, the palladium-catalyzed double C-N coupling of 9-carbazol-9-amines and 2,2'-dibromo-1,1'-biphenyl is reported. This protocol offers access to ,'-bicarbazole scaffolds, which have frequently been used as linkers in the construction of functional covalent organic frameworks (COFs). A variety of substituted ,'-bicarbazoles were synthesized in moderate to high yields based on this chemistry, and the potential application of this method was showcased by the synthesis of COF monomers like tetrabromide and tetraalkynylate .