Chen Xiao-Fei, El-Khouly Mohamed E, Ohkubo Kei, Fukuzumi Shunichi, Ng Dennis K P
Department of Chemistry, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, P. R. China.
Department of Chemistry and Nano Science, Ewha Womans University, Seoul, 120-750, Korea.
Chemistry. 2018 Mar 12;24(15):3862-3872. doi: 10.1002/chem.201705843. Epub 2018 Feb 15.
A series of light-harvesting conjugates based on a zinc(II) phthalocyanine core with either two or four boron dipyrromethene (BODIPY) or porphyrin units have been synthesized and characterized. The conjugation of BODIPY/porphyrin units can extend the absorptions of the phthalocyanine core to cover most of the visible region. Upon addition of an imidazole-substituted C (C Im), it can axially bind to the zinc(II) center of the phthalocyanine core through metal-ligand interactions. The resulting complexes form photosynthetic antenna-reaction center mimics in which the BODIPY/porphyrin units serve as the antennas to capture the light and transfer the energy to the phthalocyanine core by efficient excitation energy transfer. The excited phthalocyanine is then quenched by the axially bound C Im moiety by electron transfer, which has been supported by computational studies. The photoinduced processes of the assemblies have been studied in detail by various steady-state and time-resolved spectroscopic methods. By femtosecond transient absorption spectroscopic studies, the lifetimes of the charge-separated state of the bis(BODIPY) and bis(porphyrin) systems have been determined to be 3.2 and 4.0 ns, respectively.
一系列基于锌（II）酞菁核心、带有两个或四个硼二吡咯亚甲基（BODIPY）或卟啉单元的光捕获共轭物已被合成并表征。BODIPY/卟啉单元的共轭作用可扩展酞菁核心的吸收范围，以覆盖大部分可见光区域。加入咪唑取代的C（C Im）后，它可通过金属 - 配体相互作用轴向结合到酞菁核心的锌（II）中心。所得配合物形成光合天线 - 反应中心模拟物，其中BODIPY/卟啉单元充当天线捕获光，并通过高效的激发能量转移将能量转移到酞菁核心。然后，通过电子转移，轴向结合的C Im部分猝灭激发态的酞菁，这已得到计算研究的支持。通过各种稳态和时间分辨光谱方法详细研究了组装体的光诱导过程。通过飞秒瞬态吸收光谱研究，双（BODIPY）和双（卟啉）体系电荷分离态的寿命分别测定为3.2和4.0纳秒。
