Electrochemistry offers a sustainable synthesis route to value-added fine chemicals but is often constrained by competing electron transfer between the electrode and redox-sensitive functionalities distinct from the target site. Here, we describe an ion-shielding heterogeneous photoelectrocatalysis strategy to impose mass-transfer limitations that invert the thermodynamically determined order of electron transfer. This strategy is showcased to enable decarboxylative trifluoromethylation of sensitive (hetero)arenes by using trifluoroacetate, an inexpensive yet relatively inert trifluoromethyl group (CF 3 ) source. An ion-shielding layer, formed by trifluoroacetate anions electrostatically adsorbed on a positive molybdenum-doped tungsten trioxide (WO 3 ) photoanode, prevents undesired electron transfer between substrates and photogenerated holes. The practicality of the developed method was demonstrated with robust photoanode stability (approximately 380 hours), a good substrate scope, and scaling capability to achieve 100-gram synthesis by using photoelectrochemical flow cells.

中文翻译：

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离子屏蔽多相光电催化可扩展脱羧三氟甲基化

电化学为增值精细化学品提供了可持续的合成途径，但通常受到电极和不同于目标位点的氧化还原敏感功能之间的竞争电子转移的限制。在这里，我们描述了一种离子屏蔽异质光电催化策略，以施加传质限制，从而反转热力学确定的电子转移顺序。该策略展示了通过使用三氟乙酸酯（一种廉价但相对惰性的三氟甲基基团（CF3） 来源。离子屏蔽层，由三氟乙酸根阴离子静电吸附在正钼掺杂的三氧化钨（WO3）光电阳极，防止基板和光生空穴之间不需要的电子转移。所开发方法的实用性得到了证明，具有强大的光阳极稳定性（约 380 小时）、良好的底物范围以及使用光电化学流通池实现 100 克合成的缩放能力。