Accelerated Direct Hydroxylation of Aryl Chlorides with Water to Phenols via the Proximity Effect in a Heterogeneous Metallaphotocatalyst,ACS Catalysis

当前位置： X-MOL 学术 › ACS Catal. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Accelerated Direct Hydroxylation of Aryl Chlorides with Water to Phenols via the Proximity Effect in a Heterogeneous Metallaphotocatalyst
ACS Catalysis ( IF 11.3 ) Pub Date : 2022-05-06 , DOI: 10.1021/acscatal.1c05070
Kaixuan Wang ₁ , Huating Jiang ₁ , Helong Liu ₁ , Huiying Chen ₁ , Fang Zhang ₁

Affiliation

The proximity of different active sites in multi-catalytic systems is crucial in influencing the catalytic reactions, that is, to occur or to be accelerated. Here, we reported a heterogeneous metallaphotocatalyst prepared by embedding Ni(II) species in a photosensitive covalent organic framework (COF). A concerted triad catalytic behavior executed by electrons, holes, and Ni species triggered a dramatic catalytic enhancement in the activation of aryl chlorides with water to phenols. It demonstrated a 50-fold increment in its activity when compared to the homogeneous analogy, for example, Ni(BPDA)Br₂. Also, it was able to efficiently activate a variety of aryl chlorides to the corresponding phenols with moderate to high yields. Interestingly, it was effective even for base-sensitive substituents or chlorobenzene bearing NH or NH₂ groups. On the basis of the detailed experiments, the proximity of the photoactive COF and Ni(II) sites facilitates rapid electron transfer to produce Ni(I) active sites for the oxidative addition. Meanwhile, the photogenerated holes oxidized water to the hydroxyl radical, which then attacked Ni(III) intermediates to complete the catalytic cycle.

中文翻译：

通过非均相金属光催化剂中的邻近效应加速芳基氯与水直接羟基化生成酚类

多催化系统中不同活性位点的接近性对于影响催化反应的发生或加速至关重要。在这里，我们报道了一种通过将 Ni(II) 物种嵌入光敏共价有机框架 (COF) 中制备的非均相金属光催化剂。由电子、空穴和 Ni 物种执行的协同三元催化行为引发了用水将芳基氯化物活化为苯酚的显着催化增强。与同质类比，例如 Ni(BPDA)Br _{2相比，它的活性增加了 50 倍}. 此外，它能够以中等至高产率有效地将多种芳基氯化物活化为相应的酚类。有趣的是，它甚至对碱敏感的取代基或带有 NH 或 NH ₂基团的氯苯也有效。在详细实验的基础上，光活性 COF 和 Ni(II) 位点的接近有助于快速电子转移以产生用于氧化加成的 Ni(I) 活性位点。同时，光生空穴将水氧化成羟基自由基，然后攻击Ni(III)中间体完成催化循环。

更新日期：2022-05-06

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南