Direct and ketone-sensitized photoconversion of 1-nitro-9,10-anthraquinone to 1-amino-9,10-anthraquinone mediated by donor radicals
作者:Helmut Görner、Henry Gruen
DOI:10.1016/j.chemphys.2009.12.004
日期:2010.2
and kinetic characteristics. The short-lived triplet state (⩽20 ns) of N2 can be intercepted by 2-propanol or TEA, thereby forming the spectroscopically hidden donor radicals and the nitroAQ radicals which absorb at 400 and 540 nm; the latter band is due to the radical anion. The triplet state of N1 was not observed at room temperature, but the radical properties and decay in the nitrosoAQ are similar
在2-丙醇和三乙胺(TEA)存在下,在苯,乙腈和乙腈-水混合物中研究了1-硝基-2-R-9,10-蒽醌(R = H:N1,甲基:N2)的完全光还原)。主要的光产物是发荧光的1-氨基-2-R-AQ(A1,A2)。完全还原的量子产率与供体浓度的增加,接近Φ NH 2 =0.1ΦNH2= 0.1。所涉及的中间体是根据光谱和动力学特性进行分配的。N 2的短寿命三重态(约20 ns)可以被2-丙醇或TEA截获,从而形成了光谱上隐藏的供体自由基以及在400和540 nm处吸收的nitroAQ自由基。后一个带是由于自由基阴离子。在室温下未观察到N1的三重态,但是N1和N2的自由基性质和亚硝基AQ的衰减相似。在较低浓度的供体Φ NH 2 ΦNH2在二苯甲酮,苯乙酮或丙酮的存在强烈的增加,接近0.22。比较了直接和敏化条件下的结果,并概述了主要的依赖性以及乙腈与水的混合物的影响。