New derivatives of indazole as electronically active materials

Synthesis and thermal, optical, electrochemical and photoelectrical properties of new indazole-based electroactive materials are reported. 1-Phenyl-5(6)-[N,N-(bisphenyl)]aminoindazoles and their methoxy-substituted analogues exhibit high thermal stabilities with the onset temperatures of thermal degradation ranging from 352 to 424 °C. The synthesized indazole derivatives form glasses with glass transition temperatures ranging from 35 to 39 °C. The synthesized compounds are electrochemically stable: their cyclic voltammograms show one reversible oxidation couple and no reduction waves. The ionization potentials of the solid samples of the synthesized materials are in the range of 5.3–5.9 eV. Methoxy-substituted derivatives show lower ionization potentials. Time-of-flight hole drift mobilities of 50% solid solution of 1-(4-methoxyphenyl)-5-{N,N-[bis(4-methoxyphenyl)]}aminoindazole in bisphenol Z polycarbonate reach 10−5 cm2/V s at high electric fields.

► 1-Phenyl-5(6)-[N,N-(bisphenyl)]aminoindazoles exhibit high thermal stabilities.
► They form glasses with glass transition temperatures ranging from 35 to 39 °C.
► The ionization potentials of the solid samples are in the range of 5.3–5.9 eV
► Hole mobilities of the molecular mixtures with inert polymer reach 10−5 cm2/V s.