Reaction Chemistry at Discrete Organometallic Fragments on Black Phosphorus
Reaction Chemistry at Discrete Organometallic Fragments on Black Phosphorus
复制标题
黑磷上离散有机金属碎片的反应化学
DOI：
10.1002/anie.202311575
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Velian, Alexandra
中科院分区：
文献类型：
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作者：
Mitra, Kendahl L. Walz;Riehs, Michael;Draguicevic, Andrei;Swann, William A.;Li, Christina W.;Velian, Alexandra
黑磷（bP）是一种二维货车德瓦尔斯材料，由于其与分子膦（均相催化中的典型配体）的相似性，其独特的潜力可用作单中心催化剂的载体。然而，有一个稀缺的合成方法来安装单金属中心的bP晶格。在这里，我们展示了分子Re和Mo配合物的bP纳米片的功能化。一套表征技术，包括红外，X射线光电子和X射线吸收光谱以及扫描透射电子显微镜证实，功能化纳米片含有高密度的离散金属中心直接结合到bP表面。此外，负载的金属中心是化学上可接近的，并且可以在不从表面脱离的情况下进行配体交换转化。作为配体的空间和电子性质的bP估计相对于分子膦。在空间上，bP类似于三（甲苯基）膦时，单齿的金属中心，和双（二苯基膦基）丙烷时，双齿，而电子bP是一个σ-供体一样强的三烷基膦。这项工作是阐明黑磷作为配体的性质的基础，并强调了使用bP作为单中心催化剂基础的可行性。
Black phosphorus (bP) is a two‐dimensional van der Waals material unique in its potential to serve as a support for single‐site catalysts due to its similarity to molecular phosphines, ligands quintessential in homogeneous catalysis. However, there is a scarcity of synthetic methods to install single metal centers on the bP lattice. Here, we demonstrate the functionalization of bP nanosheets with molecular Re and Mo complexes. A suite of characterization techniques, including infrared, X‐ray photoelectron and X‐ray absorption spectroscopy as well as scanning transmission electron microscopy corroborate that the functionalized nanosheets contain a high density of discrete metal centers directly bound to the bP surface. Moreover, the supported metal centers are chemically accessible and can undergo ligand exchange transformations without detaching from the surface. The steric and electronic properties of bP as a ligand are estimated with respect to molecular phosphines. Sterically, bP resembles tri(tolyl)phosphine when monodentate to a metal center, and bis(diphenylphosphino)propane when bidentate, whereas electronically bP is a σ‐donor as strong as a trialkyl phosphine. This work is foundational in elucidating the nature of black phosphorus as a ligand and underscores the viability of using bP as a basis for single‐site catalysts.