AIE‐Active Difluoroboron Complexes with N,O‐Bidentate Ligands: Rapid Construction by Copper‐Catalyzed C−H Activation
Guangying Tan, Iván Maisuls, Felix Strieth‐Kalthoff, Xiaolong Zhang, Constantin G. Daniliuc, Cristian A. Strassert, Frank Glorius
Abstract
Abstract The development of organic materials with high solid‐state luminescence efficiency is highly desirable because of their fundamental importance and applicability in optoelectronics. Herein, a rapid construction of novel BF 2 complexes with N,O‐bidentate ligands by using Cu(BF 4 ) 2 •6H 2 O as a catalyst and BF 2 source is disclosed, which avoids the need for pre‐composing the N,O‐bidentate ligands and features a broad substrate scope and a high tolerance level for sensitive functional groups. Moreover, molecular oxygen is employed as the terminal oxidant in this transformation. A library of 36 compounds as a new class of BF 2 complexes with remarkable photophysical properties is delivered in good to excellent yields, showing a substituent‐dependency on the photophysical properties, derived from the π – π * character of the photoexcited state. In addition, aggregation‐induced emission (AIE) is observed and quantified for the brightest exemplars. The excited state properties are fully investigated in solids and in THF/H 2 O mixtures. Hence, a new series of photofunctional materials with variable photophysical properties is reported, with potential applications for sensing, bioimaging, and optoelectronics.