Intramolecular Photoredox Reaction Mechanism of Naphthoquinone Compounds: Combined Time-Resolved Spectroscopies and DFT Calculations
作者:Mingdong Dai、Mei Duan、Xuyang Li、Yan Guo、Jiani Ma
DOI:10.1021/acs.jpcb.2c05845
日期:2023.1.26
2-methyl-3-(3-methylbut-2-en-1-yl) 1,4-naphthoquinone (MNQ) were excited to singlet excited species (labeled NQ(S1) and MNQ(S1), respectively). NQ(S1) underwent intersystem crossing to produce a triplet NQ, which further underwent hydrogen atom transfer to form a biradical intermediate. The biradical underwent electron transfer to form a zwitterion, followed by cyclization and proton transfer to generate a photoproduct
利用时间分辨光谱和 DFT 计算来研究萘醌化合物的光氧化还原机制。5-Methoxy-8-tetrahydropyrane-1,4-naphthoquinone (NQ) 和 2-methyl-3-(3-methylbut-2-en-1-yl) 1,4-naphthoquinone (MNQ) 被激发到单线态激发物种(分别标记为 NQ(S 1 ) 和 MNQ(S 1 ))。NQ(S 1 )经历系统间交叉产生三重态NQ,其进一步经历氢原子转移形成双自由基中间体。双自由基经历电子转移形成两性离子,然后环化和质子转移产生光产物。MNQ(S 1) 经过 1,4-质子转移过程,产生具有两性离子特性的醌甲基中间体 (1,3-QM),互变异构为 1,2-QM。然后,1,2-QM 进行电环化。母体萘醌上的取代基是导致NQ和MNQ反应过程不同的关键因素。