Azaindolo[3,2,1-jk]carbazoles: New Building Blocks for Functional Organic Materials.

The preparation and characterization of 12 azaindolo[3,2,1-jk]carbazoles is presented. Ring-closing C-H activation allowed for the convenient preparation of six singly and six doubly nitrogen-substituted indolo[3,2,1-jk]carbazole derivatives in which ten of the materials have not been described in the literature before. The detailed photophysical and electrochemical characterization of the developed materials revealed a significant impact of the incorporation of pyridine-like nitrogen into the fully planar indolo[3,2,1-jk]carbazole backbone. Furthermore, the nitrogen position decisively impacted intermolecular hydrogen bonding and thus the solid-state alignment. Ultimately, the versatility of the azaindolo[3,2,1-jk]carbazoles scaffold makes this class of materials an attractive new building block for the design of functional organic materials.