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AIE-Active Difluoroboron Complexes with N,O-Bidentate Ligands: Rapid Construction by Copper-Catalyzed C-H Activation.

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 BF₂ complexes with N,O-bidentate ligands by using Cu(BF₄ )₂ •6H₂ O as a catalyst and BF₂ 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 BF₂ 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/H₂ O mixtures. Hence, a new series of photofunctional materials with variable photophysical properties is reported, with potential applications for sensing, bioimaging, and optoelectronics.

SUBMITTER: Tan G

PROVIDER: S-EPMC8456238 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Tunable intramolecular multicenter H-bonding interactions in first-row metal complexes bearing bidentate redox-active ligands.

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