光氧化反应的研究 II: 9-苯甲叉芴的电子转移光氧化反应

芳香族烯烃, 芳烃以及稠环芳烃是光氧化反应中的重要研究对象, 本文以9-苯甲叉芴(BF)作为底物, 发现它在9,11-二氰蒽(DCA)敏化作用下易发生电子转移反应, 反应生成芴酮和BF的相应环氧化物, 用紫外光谱测出BF的电荷转移配合物的络合物稳定常数,用循环伏安法测定BF的氧化电位. 由Rehm-Weller方程计算出DCA敏化的单电子转移过程的自由能变化, 并观察到BF对DCA有明显的荧光猝灭作用.

Studies on photooxidations II: Electron transfer photooxidation of 9-benzylidene fluorene

Some sensitizers were used to initiate the photooxidn. of 9-benzylidenefluorene(BF). The sensitizer 9, 10-dicyanoanthracene (DCA) was particularly effective on the reaction, leading to the formation of fluorenone and the corresponding epoxide of BF. The photooxidn. was proposed to proceed via electron transfer (ET) mechanism. Some evidences were given from UV spectrometry, cyclic voltammetry as well as Rehm-Weller theory for ET processes. Furthermore, an apparent quenching effect of BF on the fluorescence of DCA followed the Stern-Volmer equation, which indicated that the ET photooxidn. was diffusion-controlled and was consistent with the ET mechanism suggested.