Cao Chun-Shuai, Xia Shu-Mei, Song Zhen-Jun, Xu Hang, Shi Ying, He Liang-Nian, Cheng Peng, Zhao Bin
Key Laboratory of Advanced Energy Material Chemistry (Ministry of Education), College of Chemistry, Nankai University, Tianjin, 300071, China.
College of Environmental Science and Engineering, Nankai University, Tianjin, 300350, China.
Angew Chem Int Ed Engl. 2020 May 25;59(22):8586-8593. doi: 10.1002/anie.201914596. Epub 2020 Mar 20.
The reaction of propargylic amines and CO can provide high-value-added chemical products. However, most of catalysts in such reactions employ noble metals to obtain high yield, and it is important to seek eco-friendly noble-metal-free MOFs catalysts. Here, a giant and lantern-like [Zn ] nanocage in zinc-tetrazole 3D framework [Zn (Trz) (OH) (H O) ⋅8 H O] Trz=(C N O) (1) was obtained and structurally characterized. It consists of six [Zn O ] clusters and eight [Zn O ] clusters. To our knowledge, this is the highest-nuclearity nanocages constructed by Zn-clusters as building blocks to date. Importantly, catalytic investigations reveal that 1 can efficiently catalyze the cycloaddition of propargylic amines with CO , exclusively affording various 2-oxazolidinones under mild conditions. It is the first eco-friendly noble-metal-free MOFs catalyst for the cyclization of propargylic amines with CO . DFT calculations uncover that Zn ions can efficiently activate both C≡C bonds of propargylic amines and CO by coordination interaction. NMR and FTIR spectroscopy further prove that Zn-clusters play an important role in activating C≡C bonds of propargylic amines. Furthermore, the electronic properties of related reactants, intermediates and products can help to understand the basic reaction mechanism and crucial role of catalyst 1.
炔丙基胺与一氧化碳的反应能够提供高附加值的化学产品。然而，此类反应中的大多数催化剂都使用贵金属以获得高产率，因此寻找环保型无贵金属的金属有机框架（MOF）催化剂具有重要意义。在此，我们获得了一种位于锌-四唑三维框架[Zn₄(Trz)₆(OH)₂(H₂O)₂·8 H₂O]（Trz = C₂N₂H₂）中的巨大灯笼状[Zn₄₀]纳米笼（1），并对其结构进行了表征。它由六个[Zn₄O₆]簇和八个[Zn₄O₅]簇组成。据我们所知，这是迄今为止以锌簇为构建单元构建的核数最高的纳米笼。重要的是，催化研究表明，1能够有效催化炔丙基胺与一氧化碳的环加成反应，在温和条件下专一性地生成各种2-恶唑烷酮。它是首例用于炔丙基胺与一氧化碳环化反应的环保型无贵金属MOF催化剂。密度泛函理论（DFT）计算表明，锌离子可通过配位相互作用有效活化炔丙基胺的C≡C键和一氧化碳。核磁共振（NMR）和傅里叶变换红外光谱（FTIR）进一步证明，锌簇在活化炔丙基胺的C≡C键中起着重要作用。此外，相关反应物、中间体和产物的电子性质有助于理解基本反应机理以及催化剂1的关键作用。
