BN-Benzo[b]fluoranthenes: facile synthesis, characterization, and optoelectronic properties

A series of BN-benzo[b]fluoranthenes have been synthesized through straightforward N-directed borylative cyclization. Their photophysical properties were investigated by the combination of experimental and theoretical studies, revealing significant electronic modifications in comparison with their carbonaceous analogues. In particular, BN-benzo[b]fluoranthenes with amino groups exhibit blue emission which is largely red-shifted compared to that of other title compounds. TD-DFT calculations reveal that the installation of amino groups led to the origin of emission behavior from the local excited-state (LE) to the charge-transfer state (CT) transition. Moreover, organic light-emitting diodes were fabricated using 2 as emitters, demonstrating the potential applications of BN-benzo[b]fluoranthenes as OLED emitting materials.