Gon Masayuki, Tanaka Kazuo, Chujo Yoshiki
Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto, 615-8510, Japan.
Angew Chem Int Ed Engl. 2018 May 28;57(22):6546-6551. doi: 10.1002/anie.201803013. Epub 2018 Apr 26.
Fused azobenzene-boron complexes (BAzs) show highly efficient near-infrared (NIR) emission from the nitrogen-nitrogen double bond (N=N) containing π-conjugated copolymer. Optical measurements showed that BAz worked as a strong electron acceptor because of the intrinsic electron deficiency of the N=N double bond and the boron-nitrogen (B-N) coordination which dramatically lowered the energy of the lowest unoccupied molecular orbital (LUMO) of the azobenzene ligand. The simple donor-acceptor (D-A) type copolymer of bithiophene (BT) and BAz exhibited intense photoluminescence (PL) in the NIR region both in the dilute solution (λ =751 nm, Φ =0.25) and in the film (λ =821 nm, Φ =0.038). The BAz monomer showed slight PL in the dilute solution, and aggregation-induced emission (AIE) was detected. We proposed that N=N double bonds should be attractive and functional building blocks for designing π-conjugated materials.
稠合偶氮苯-硼配合物（BAzs）在含氮氮双键（N=N）的π共轭共聚物中表现出高效的近红外（NIR）发射。光学测量表明，由于N=N双键固有的电子缺乏以及硼氮（B-N）配位显著降低了偶氮苯配体最低未占据分子轨道（LUMO）的能量，BAz作为强电子受体发挥作用。双噻吩（BT）和BAz的简单供体-受体（D-A）型共聚物在稀溶液（λ =751 nm，Φ =0.25）和薄膜（λ =821 nm，Φ =0.038）中均在近红外区域表现出强烈的光致发光（PL）。BAz单体在稀溶液中表现出轻微的PL，并检测到聚集诱导发光（AIE）。我们提出，N=N双键对于设计π共轭材料应是有吸引力的功能性结构单元。
