Lin Liangbin, Lin Xiaoru, Guo Hongyu, Yang Fafu
College of Chemistry and Chemical Engineering, Fujian Normal University, Fuzhou 350007, P. R. China.
Org Biomol Chem. 2017 Jul 19;15(28):6006-6013. doi: 10.1039/c7ob01270e.
This study focuses on the construction of novel diphenylacrylonitrile-connected BODIPY dyes with high fluorescence in both solution and an aggregated state by combining DRET and FRET processes in a single donor-acceptor system. The first BODIPY derivatives with one, two, or three AIE-active diphenylacrylonitrile groups were designed and synthesized in moderate yields. Strong fluorescence emissions were observed in the THF solution under excitation at the absorption wavelength of non-emissive diphenylacrylonitrile chromophores, implying the existence of the DRET process between the dark diphenylacrylonitrile donor and the emissive BODIPY acceptor. In the THF/HO solution, the fluorescence intensity of the novel BODIPY derivatives gradually increased under excitation at the absorption wavelength of diphenylacrylonitrile chromophores, suggesting a FRET process between diphenylacrylonitrile and BODIPY moieties. A greater number of diphenylacrylonitrile units led to higher energy-transfer efficiencies. The pseudo-Stokes shift for both DRET and FRET processes was as large as 190 nm.
本研究聚焦于通过在单一供体 - 受体体系中结合DRET和FRET过程，构建在溶液态和聚集态均具有高荧光的新型二苯丙烯腈连接的BODIPY染料。设计并合成了具有一个、两个或三个AIE活性二苯丙烯腈基团的首批BODIPY衍生物，产率适中。在非发射性二苯丙烯腈发色团的吸收波长激发下，在THF溶液中观察到强荧光发射，这意味着暗二苯丙烯腈供体与发射性BODIPY受体之间存在DRET过程。在THF/H₂O溶液中，新型BODIPY衍生物在二苯丙烯腈发色团的吸收波长激发下荧光强度逐渐增加，表明二苯丙烯腈与BODIPY部分之间存在FRET过程。更多数量的二苯丙烯腈单元导致更高的能量转移效率。DRET和FRET过程的伪斯托克斯位移均高达190 nm。
