ICMUB, UMR CNRS 6302, Université de Bourgogne, 9 Avenue Alain Savary, BP 47870, 21078 Dijon Cedex, France.
J Phys Chem A. 2012 Apr 19;116(15):3889-98. doi: 10.1021/jp300415a. Epub 2012 Apr 5.
Novel zinc porphyrin tweezers in which two zinc porphyrins were connected with π-conjugated boron dipyrromethenes (BDP meso-Por(2) and BDP β-Por(2)) through triazole rings were synthesized to investigate the photoinduced energy transfer and electron transfer. The UV-vis spectrum of BDP β-Por(2) which has less bulky substituents than BDP meso-Por(2) exhibits splitting of the Soret band as a result of the interaction between porphyrins of BDP β-Por(2) in the excited state. Such interaction between porphyrins of both BDP β-Por(2) and BDP meso-Por(2) is dominant at room temperature, while the coordination of the nitrogen atoms of the triazole rings to the zinc ions of the porphyrins occurs at low temperature. The conformational change of the BDP-porphyrin composites was confirmed by the changes in UV-vis and fluorescence spectra depending on temperature. Photodynamics of BDP meso-Por(2) and BDP β-Por(2) has also been investigated by laser flash photolysis. Efficient singlet-singlet energy transfer from the ZnP to the π-conjugated BDP moiety of both BDP meso-Por(2) and BDP β-Por(2) occurred in opposite direction as compared to energy transfer from conventional BDP to ZnP due to the π-conjugation in nonpolar toluene. In polar benzonitrile, however, additional electron transfer occurred along with energy transfer.
合成了通过三唑环连接两个锌卟啉的新型锌卟啉镊子，其中两个锌卟啉通过π-共轭硼二吡咯甲川（BDP meso-Por(2) 和 BDP β-Por(2)）连接。研究了光诱导能量转移和电子转移。BDP β-Por(2) 的紫外可见光谱由于 BDP β-Por(2) 的卟啉在激发态下的相互作用而出现 Soret 带分裂，BDP β-Por(2) 的取代基比 BDP meso-Por(2) 少。这种相互作用在室温下是占主导地位的，而三唑环的氮原子与卟啉的锌离子的配位在低温下发生。BDP-porphyrin 复合材料的构象变化通过随温度变化的紫外可见和荧光光谱得到证实。还通过激光闪光光解研究了 BDP meso-Por(2) 和 BDP β-Por(2) 的光动力学。与从常规 BDP 到 ZnP 的能量转移相比，由于非极性甲苯中的π-共轭，来自 ZnP 的能量有效地从 BDP meso-Por(2) 和 BDP β-Por(2) 的 π-共轭 BDP 部分向相反方向发生单重态-单重态能量转移。然而，在极性苯腈中，随着能量转移发生额外的电子转移。
