Synthesis of unsymmetrical triarylamines for photonic applications via one-pot palladium-catalyzed aminations

Syntheses of unsymmetrically substituted triarylamines have been achieved by a one-pot procedure using C-N bond-forming reactions, where two aryl bromides are sequentially added to an arylamine in the presence of a palladium catalyst. This methodology has been utilized to synthesize a number of substituted analogs of 4,4'-bis(m-tolylphenylamino)-biphenyl, which may be useful as the hole transport component of vapor-deposited organic light-emitting diodes. The variations in the substitution are anticipated to lead to a variety of band gaps, band offsets, and glass transition temperatures in this class of materials.