Investigating carbazole jacketed precursor dendrimers: sonochemical synthesis, characterization, and electrochemical crosslinking properties

Precursor carbazole terminated dendrons and dendrimers up to generation four (G4-D) were synthesized using a convergent approach. Sonication as a means of facilitating organic reactions in dendrimer chemistry was explored resulting in very facile and very fast (up to 50x) reaction times compared to those using traditional reflux conditions. The limits of peripheral group functionality were explored as a function of generation. The electrochemical cross-linking of the dendrimers as thin films revealed unusual cyclic voltammetry (CV) behavior depending upon the generations, which were significantly different from their linear counterpart, Poly(N-vinylcarbazole) (PVK). G1-D showed a higher extent of intermolecular cross-linking while G4-D showed a higher extent of intramolecular cross-linking. The formed films were optically clear and possess superior energy band gap properties making them an alternative candidate over PVK for future hole-transport layer materials in electro-optical devices.