关键词: 香豆素, 碘鎓盐, 电子转移

Abstract: The fluorescence quenching of three coumarin derivatives by three iodonium Salts was studied in this work. It is found that the quenching curves follow the Stern-Volmer equation and the quenching processes are controlled by diffusion. The results are thoroughly discussed. An electron transfer mechanism of the quenching was proposed and was proved by the ability of coumarin-iodonium salt systems to initiate the polymerization of MMA under irradiation. Due to the low redox potentials of iodonium salts’ and excellent ability to accept electrons, the electron transfer rates between coumarins and iodonium salts are very fast when they are irradiated in spite of coumarins’ tendency of intramolecular charge-transfer.

Key words: coumarin, iodonium salt, electron-transfer