Electrophotocatalysis with a Trisaminocyclopropenium Radical Dication
Electrophotocatalysis with a Trisaminocyclopropenium Radical Dication
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DOI：
10.1002/anie.201906381
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发表时间：
2019-08-02
影响因子：
16.6
通讯作者：
Lambert, Tristan H.
中科院分区：
文献类型：
--
作者：
Huang, He;Strater, Zack M.;Lambert, Tristan H.
可见光催化和电催化是促进化学反应的两种强有力的策略。在这里，这两种模式结合在一个电光催化氧化平台。该化学方法采用三氨基环丙烯鎓（TAC）离子催化剂，其被电化学氧化以形成环丙烯鎓自由基二价阳离子中间体。自由基的二价阳离子进行光激发与可见光产生的激发态物种的氧化能力（3.33 V vs. SCE）足以氧化苯和卤代苯通过单电子转移（SET），导致C-H/N-H偶联与唑。的光激发物种的强氧化行为的理由提供，而催化剂的稳定性是合理化的顺式-2，6-二甲基哌啶部分的特定构象。
Visible-light photocatalysis and electrocatalysis are two powerful strategies for the promotion of chemical reactions. Here, these two modalities are combined in an electrophotocatalytic oxidation platform. This chemistry employs a trisaminocyclopropenium (TAC) ion catalyst, which is electrochemically oxidized to form a cyclopropenium radical dication intermediate. The radical dication undergoes photoexcitation with visible light to produce an excited-state species with oxidizing power (3.33 V vs. SCE) sufficient to oxidize benzene and halogenated benzenes via single-electron transfer (SET), resulting in C-H/N-H coupling with azoles. A rationale for the strongly oxidizing behavior of the photoexcited species is provided, while the stability of the catalyst is rationalized by a particular conformation of the cis-2,6-dimethylpiperidine moieties.