Photophysics and photochemistry of nitroanthracenes. Part 1.—Primary processes in the photochemical reactions of 9-benzoyl-10-nitroanthracene and 9-cyano-10-nitroanthracene studied by steady-state photolysis and nanosecond laser photolysis
作者:Kumao Hamanoue、Toshihiro Nakayama、Kiminori Ushida、Kanji Kajiwara、Shigenobu Yamanaka
DOI:10.1039/ft9918703365
日期:——
The genuine phosphorescence spectra of the title compounds (XNA) have been clearly observed at 77 K in EPA (diethyl ether–isopentane–ethanol 5 : 5 : 2 volume ratio). Also, the time-resolved absorption spectra obtained at the end of nanosecond laser pulse at 77 K (in EPA) and at room temperature (in ethanol and benzene) have been ascribed to the superposition of the absorptions of the lowest triplet
在EPA中(二乙醚–异戊烷–乙醇5:5:2体积比)在77 K下可以清楚地观察到标题化合物(XNA)的真正磷光光谱。另外,在纳秒激光脉冲结束时在EPA(在77 K下)和室温(在乙醇和苯中)所获得的时间分辨吸收光谱已归因于最低的三重态XNA [ 3 XNA (T 1)]上的相应的烷氧基基团(XAO 3)。3 XNA(T 1的衰减)不伴随有XAO˙的形成,得到以下结果。(1)在室温下的乙醇中,XAO˙的一阶衰变对应于XAO˙从溶剂中夺取氢原子,从而形成相应的蒽酚(XAOH),而XAO的二阶反应˙用氮气(II)氧化物(NO)产生,其分解速度非常慢进XAO和没有相应nitrosoanthrones(XNSAN),接着迅速形成XAOH的。(2)在室温下的苯中未观察到XAOH的形成,但XAO˙(+NO˙)和XNSAN之间存在平衡。所有这些结果支持我们先前的结论,即对于ππ的最低三重态,不会发生XNA的亚