Organic high-spin systems of oligoarylamines: Properties of tetraaryl-m-phenylendiamine oligocations as examined by electron transfer stopped-flow method

Three types of N,N,N′,N′-tetraaryl-1,3-phenylenediamines with bromo atoms as protecting groups were designed and synthesized. Electrochemical and novel electron transfer stopped-flow (ETSF) methods were invoked for characterizing the absorption spectra of the corresponding short-lived mono- and dicationic states. Useful molecular design rules for stabilizing the dicationic states of N,N,N′,N′-tetraaryl-1,3-phenylenediamines as precursors for positively charged high-spin systems were elucidated. An extended system, 3,3′-bis(diphenylamino)triphenylamine in the tricationic state with four bromo groups was also examined, being confirmed to give a ground-state triplet dication by ESR spectroscopy.

Graphical abstractTriarylamine-based diamines and triamines were synthesized as precursors of positvely charged high-spin systems. Their electrochemical and spectroscopic prooerties were examined.Figure optionsDownload full-size imageDownload as PowerPoint slide