Repp Stefan, Remmers Moritz, Rein Alexandra Stefanie Jessica, Sorsche Dieter, Gao Dandan, Anjass Montaha, Mondeshki Mihail, Carrella Luca M, Rentschler Eva, Streb Carsten
Institute of Inorganic Chemistry I, Ulm University, Albert-Einstein-Allee 11, 89081, Ulm, Germany.
Department of Chemistry, Johannes Gutenberg University Mainz, Duesbergweg 10-14, 55128, Mainz, Germany.
Nat Commun. 2023 Sep 9;14(1):5563. doi: 10.1038/s41467-023-41257-y.
The introduction of metal sites into molecular metal oxides, so-called polyoxometalates, is key for tuning their structure and reactivity. The complex mechanisms which govern metal-functionalization of polyoxometalates are still poorly understood. Here, we report a coupled set of light-dependent and light-independent reaction equilibria controlling the mono- and di-metal-functionalization of a prototype molecular vanadium oxide cluster. Comprehensive mechanistic analyses show that coordination of a Mg ion to the species {(NMeH)[VOCl]} results in formation of the mono-functionalized {(NMeH)[(MgCl)VOCl]} with simultaneous release of a NMeH placeholder cation. Irradiation of this species with visible light results in one-electron reduction of the vanadate, exchange of the second NMeH with Mg, and formation/crystallization of the di-metal-functionalized [(MgCl)VVOCl]. Mechanistic studies show how stimuli such as light or competing cations affect the coupled equilibria. Transfer of this synthetic concept to other metal cations is also demonstrated, highlighting the versatility of the approach.
将金属位点引入分子金属氧化物（即所谓的多金属氧酸盐）中，是调节其结构和反应活性的关键。然而，目前对于多金属氧酸盐金属功能化的复杂机制仍知之甚少。在此，我们报道了一组耦合的光依赖和光独立反应平衡，它们控制着原型分子钒氧化物簇的单金属和双金属功能化。全面的机理分析表明，镁离子与{(NMeH)[VOCl]}物种配位会导致形成单功能化的{(NMeH)[(MgCl)VOCl]}，同时释放出一个NMeH占位阳离子。用可见光照射该物种会导致钒酸盐发生单电子还原，第二个NMeH与镁进行交换，并形成/结晶出双金属功能化的[(MgCl)VVOCl]。机理研究展示了光或竞争性阳离子等刺激因素如何影响耦合平衡。此外，还证明了将这种合成概念转移到其他金属阳离子上，突出了该方法的通用性。
