Korth Hans-Gert
Institut für Organische Chemie, Universität Duisburg-Essen, Universitätsstr. 7, 45117, Essen, Germany.
Chemistry. 2020 Oct 6;26(56):12747-12750. doi: 10.1002/chem.202003437. Epub 2020 Sep 16.
EPR spectroscopic evidence for intramolecular electron transfer in anionic N-substituted naphthalimides to yield persistent diradical anions and intermolecular electron transfer from a variety of carbanions to 6-bromo-N-phenyl-naphthalimide to yield persistent radical-radical anion pairs was recently claimed in two papers by Zhang et al. In this comment, it is shown that the EPR spectra published in both papers do not agree with the proposed triplet-state species. Rather, the spectra are due to various doublet-state radicals, deriving from minor side reactions. The misinterpretations invalidate the general conclusions of the papers.
张等人最近在两篇论文中声称,有电子顺磁共振(EPR)光谱证据表明,阴离子型N-取代萘二甲酰亚胺中存在分子内电子转移,生成持久的双自由基阴离子;以及各种碳负离子向6-溴-N-苯基萘二甲酰亚胺发生分子间电子转移,生成持久的自由基-自由基阴离子对。在本评论中,我们表明这两篇论文中发表的EPR光谱与所提出的三重态物种不一致。相反,这些光谱是由各种双态自由基产生的,这些自由基源于次要的副反应。这些错误解读使论文的总体结论无效。