磺酰脒基桥连的锌卟啉-富勒烯化合物构型对光诱导电子转移机理的影响

Influence of Configuration on Photoinduced Electron-transfer Mechanism in Sulfonyl Amidine Linked Porphyrin-fullerene Dyad

通过"一锅法"多组分偶联反应合成了一种新型磺酰脒基桥连的卟啉-富勒烯化合物ZnP-H-C60.该化合物具有Z式和E式2种异构体,其中Z式异构体中含有分子内氢键.光物理研究结果表明,2种异构体中的卟啉与富勒烯之间都可以发生光诱导电子转移,但其相应的电子转移机理却完全不同.在Z式异构体中,卟啉或富勒烯被激发后直接发生电荷分离而形成电荷分离态,其电荷分离机理是通过氢键进行电子传递;在E式异构体中,由于卟啉和富勒烯之间存在空间电子相互作用,被激发后先形成卟啉-富勒烯激基复合物,再进一步发生电荷分离形成电荷分离态,电荷分离通过空间电子转移实现.

A novel sulfonyl amidine linked porphyrin-fullerene dyad ZnP-H-C60 was facilely synthesized via a three components one-pot coupling reaction. There are two isomers （Z- and E-） in the dyad solution in low- polarity solvents, such as chloroform and toluene. We found that the photoinduced electron-transfer （PET） process could occur in two isomers, but the electron-transfer mechanism was different from each other. The electron transfer process was mediated by the intramolecular hydrogen-bond in （Z-）ZnP-H-C60; and in （E-） ZnP-H-Cr0, the porphyrin-fullerene exciplex was the precursor of the charge separation（CS） state due to the closer distance between porphyrin and fullerene entities.