红光区双效发光材料BODIPY的制备及其光谱性质

Preparation and photophysical properties of red region dual-state emission BODIPY

通过吲哚衍生物与1,8-萘内酰亚胺缩合及氟硼化反应,得到meso位无取代和甲基取代的两种配体(Ⅰ、Ⅲ)及两种氟硼二吡咯(BODIPY)染料(Ⅱ、Ⅳ)。其结构和光学性能经NMR、HRMS、单晶、UV-Vis吸收光谱、荧光发射光谱和固体荧光光谱进行了表征。结果表明,meso位引入甲基后配体Ⅲ较配体Ⅰ的固体荧光发射峰红移了34 nm。BODIPY染料具有较强的双效荧光(溶液和固体荧光),其中BODIPY染料Ⅳ的溶液和固体荧光量子产率分别高达65.8%和76.3%,其固体荧光量子产率较meso位无取代BODIPY染料Ⅱ(14.6%)提高了4.2倍。BODIPY染料Ⅳ较强的双效发光可归因于其固体堆积方式中无C—H…π作用以及层与层之间存在的“头-尾”π-π堆积。不同于其他提高固态荧光的策略,在母体meso位引入小位阻甲基的策略使BODIPY具有双效红光发射性能,也丰富了双效有机发光材料的种类。

Two meso-unsubstituted ligands(Ⅰ,Ⅲ)and two methyl group substituted N,N-fluoroborate complex(BODIPY)dyes(Ⅱ,Ⅳ)were synthesized from condensation and coordination reactions of indole derivatives and 1,8-naphthalenimide.The structures and spectral properties of products obtained were characterized by NMR,HRMS,single crystal,UV-Vis absorption spectrum,fluorescence emission spectrum and solid fluorescence spectrum.The results indicated that the introduction of methyl group at meso-position made the solid emission spectra of ligandⅢred-shift 34 nm compared with that of ligandⅠ.BODIPY dyes displayed high intensity fluorescence in dual state(solution state and solid state),especially,the corresponding fluorescence quantum yields ofⅣwere as high as 65.8%and 76.3%,with solid fluorescence quantum yield 4.2 times higher than that ofⅡ(14.6%).The excellent optical properties ofⅣcould be attributed to the absence of C—H…πinteraction and different"head to tail"π-πstacking between layers.Different from other strategies in solid-state fluorescence improvement,the strategy of introducing small steric methyl group in the parent meso site made BODIPY exhibit dual-effect red light emission performance,and enriched the types of dual-effect organic luminescent materials as well.