Bis-BN-Embedded [4]helicenes: Synthesis, Structures and Properties

Abstract

A series of bis-BN-embedded [4]helicenes were successfully synthesized through a sequential nitrogen-directed electrophilic borylation strategy. Single-crystal X-ray diffraction unequivocally confirmed their highly twisted helical frameworks. Additionally, BN embedding allows precise modulation of frontier orbital energy levels and significantly enhances the fluorescence quantum yields of these compounds. Preliminary results show that blue organic light-emitting diodes (OLEDs) can be fabricated using 4a and 4b as the emissive layers.