Cationic DABCO-Based Catalyst for Site-Selective C-H Alkylation via Photoinduced Hydrogen-Atom Transfer
Cationic DABCO-Based Catalyst for Site-Selective C-H Alkylation via Photoinduced Hydrogen-Atom Transfer
复制标题
基于 DABCO 的阳离子催化剂通过光诱导氢原子转移进行位点选择性 C-H 烷基化
DOI：
10.1021/acscatal.1c05484
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发表时间：
2022
期刊：
影响因子：
12.9
通讯作者：
Keiji Maruoka
中科院分区：
文献类型：
--
作者：
Akira Matsumoto;Masanori Yamamoto;Keiji Maruoka
设计了一系列基于1，4-二氮杂双环[2.2.2]辛烷（DABCO）结构的光诱导氢原子转移（HAT）催化剂，并对其光诱导HAT催化性能进行了研究。我们的HAT催化剂与吖啶鎓基有机光氧化还原催化剂的组合能够实现从未活化的烃到复杂分子的底物的有效和位点选择性C-H烷基化。值得注意的是，具有与氮原子相邻的额外取代基的HAT催化剂进一步改善了位点选择性。机理研究表明，催化剂的N-取代基起着至关重要的作用，有助于产生一个双阳离子铵自由基作为HAT过程的活性物种。
A series of hydrogen-atom transfer (HAT) catalysts based on the readily available and tunable 1,4-diazabicyclo[2.2.2]octane (DABCO) structure was designed, and their photoinduced HAT catalysis ability was demonstrated. The combination of our HAT catalyst with an acridinium-based organophotoredox catalyst enables efficient and site-selective C–H alkylation of substrates ranging from unactivated hydrocarbons to complex molecules. Notably, a HAT catalyst with additional substituents adjacent to a nitrogen atom further improved the site selectivity. Mechanistic studies suggested that theN-substituent of the catalyst plays a crucial role, assisting in the generation of a dicationic aminium radical as an active species for the HAT process.