meso -RNH(R = C 3 H 7、C 4 H 9、PhCH 2、H 和 Ph)取代的 BODIPY 化合物已被制备出来以检测它们的光物理性质和光敏能力。我们已经测量了紫外-可见吸收、稳态和时间分辨荧光、使用激光闪光光解的激发三重态形成、使用化学捕获方法的单线态氧生成能力。结果表明,meso的存在-RNH导致吸收和发射波长发生较大的蓝移,荧光量子产率和寿命值显着降低,单线态氧形成量子产率显着增加。量子化学计算还揭示了光致电荷转移 (PCT) 机制。我们得出结论,属性变化归因于:1) S 0和 S 1几何结构,2) 基态结构异构化,以及 3) 分子内 PCT。这些结果和机制有助于设计新的功能材料。
8-Amino-BODIPYs: Structural Variation, Solvent-Dependent Emission, and VT NMR Spectroscopic Properties of 8-R<sub>2</sub>N-BODIPY
作者:Robinson I. Roacho、Alejandro Metta-Magaña、Michelle M. Portillo、Eduardo Peña-Cabrera、Keith H. Pannell
DOI:10.1021/jo302758a
日期:2013.5.3
New 8-NR2-BODIPYs, R-2 = (HPr)-Pr-i (3a) (HBu)-Bu-i (3b), and Et-2 (4), are reported. Restricted rotation about the C8-N bond in such molecules has been observed for the first time (3a and 3b) and evaluated using VT NMR. The fluorophores 3a and 3b are blue emitters, and the efficiency of the emission is closely related to the polarity of the solvent, e.g., hexane > toluene > DCM > THF > MeOH > H2O, an effect also noted by emission variation in alcohol solvents H(CH2)(n)OH, n = 1-6. In mixed-solvents systems, addition of 10-15% of the more polar solvent results in transformation of the emission properties to those of the bulk polar solvent. Compound 4 has zero emission in all solvents. The crystal structures of 3a, 3b and 4 are reported, along with that of the present 8-NH2-BODIPY (2). Compounds 2, 3a, and 3b exhibit trigonal planar N atoms which are coplanar with the BODIPY core; 4 exhibits a very significant distortion that breaks the planarity of the extended BODIPY pi system due to the steric impact of the two ethyl groups, and observation that explains the lack of emission for 4.