Photocatalyst size controls electron and energy transfer: selectable E/Z isomer synthesis via C-F alkenylation.
Photocatalyst size controls electron and energy transfer: selectable E/Z isomer synthesis via C-F alkenylation.
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DOI：
10.1039/c6sc02422j
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发表时间：
2016-11-18
期刊：
影响因子：
8.4
通讯作者：
Weaver JD
中科院分区：
文献类型：
--
作者：
Singh A;Fennell CJ;Weaver JD
这项工作突出了光催化剂体积在控制光猝灭事件中的作用，并被用来控制反应结果。光催化烯烃合成涉及电子和能量转移过程。光催化剂的结构可用于控制能量转移的速率，从而提供对这两个过程的机械处理。联合考虑催化剂体积和发射能量提供了一个高度敏感的策略，预测哪种机制途径将占主导地位。该模型是在炔烃和高度氟化的芳烃作为伴侣的光催化Caryl-F烯基化反应的途中开发的。通过明智地选择光催化剂，即使在合成具有挑战性的三取代烯烃的情况下，也可以获得E-或Z-烯烃。该模型的通用性和可转移性进行了测试，通过评估建立的光催化反应，导致缩短反应时间和获得互补的Z-肉桂胺的光催化[2 + 2]和C-H乙烯化胺，分别。这些结果表明，考虑光催化剂的尺寸提供了光化学猝灭事件中的预测能力和控制。
This work highlights the role of photocatalyst volume in controlling photoquenching events and is exploited to control the reaction outcomes. Photocatalytic alkene synthesis can involve electron and energy transfer processes. The structure of the photocatalyst can be used to control the rate of the energy transfer, providing a mechanistic handle over the two processes. Jointly considering catalyst volume and emissive energy provides a highly sensitive strategy for predicting which mechanistic pathway will dominate. This model was developed en route to a photocatalytic Caryl–F alkenylation reaction of alkynes and highly-fluorinated arenes as partners. By judicious choice of photocatalyst, access to E- or Z-olefins was accomplished, even in the case of synthetically challenging trisubstituted alkenes. The generality and transferability of this model was tested by evaluating established photocatalytic reactions, resulting in shortened reaction times and access to complimentary Z-cinnamylamines in the photocatalytic [2 + 2] and C–H vinylation of amines, respectively. These results show that taking into account the size of the photocatalyst provides predictive ability and control in photochemical quenching events.