metal-organic polyhedra

  • 文章类型: Journal Article
    使用配位驱动的自组装设计和合成多面体一直是合成化学家感兴趣的研究领域。金属有机多面体是一类复杂的分子结构,由于其不同的结构和潜在的应用,在文献中引起了极大的关注。特此,我们报道了Cu-MOP,在室温下使用2,6-二甲基吡啶-3,5-二羧酸和乙酸铜构建的双功能金属有机立方体。Lewis碱性吡啶基和Lewis酸性铜位点的存在都为串联的一锅脱缩醛-Knoevenagel/Henry反应赋予了Cu-MOP催化活性。研究了溶剂体系和持续时间对反应收率的影响,结果说明了这些金属有机立方面体的潜力,也称为纳米球在催化中的应用。
    The design and synthesis of polyhedra using coordination-driven self-assembly has been an intriguing research area for synthetic chemists. Metal-organic polyhedra are a class of intricate molecular architectures that have garnered significant attention in the literature due to their diverse structures and potential applications. Hereby, we report Cu-MOP, a bifunctional metal-organic cuboctahedra built using 2,6-dimethylpyridine-3,5-dicarboxylic acid and copper acetate at room temperature. The presence of both Lewis basic pyridine groups and Lewis acidic copper sites imparts catalytic activity to Cu-MOP for the tandem one-pot deacetalization-Knoevenagel/Henry reactions. The effect of solvent system and time duration on the yields of the reactions was studied, and the results illustrate the promising potential of these metal-organic cuboctahedra, also known as nanoballs for applications in catalysis.
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  • 文章类型: Journal Article
    Clip-offChemistry是我们小组先前开发的一种合成策略,旨在通过键的选择性裂解获得新的分子和材料。在这里,我们报告了最近的工作,通过向其中引入一个逆向分析步骤来扩展Clip-offChemistry,基于产品通过可裂解债券的虚拟扩展,使人们能够定义所需的前体材料。作为概念证明,我们通过合成和表征四种醛官能化Rh(II)基复合物来验证我们的新方法:同质簇;顺式双取代的桨轮簇;大环;和冠。
    Clip-off Chemistry is a synthetic strategy that our group previously developed to obtain new molecules and materials through selective cleavage of bonds. Herein, we report recent work to expand Clip-off Chemistry by introducing into it a retrosynthetic analysis step that, based on virtual extension of the products through cleavable bonds, enables one to define the required precursor materials. As proof-of-concept, we have validated our new approach by synthesising and characterising four aldehyde-functionalised Rh(II)-based complexes: a homoleptic cluster; a cis-disubstituted paddlewheel cluster; a macrocycle; and a crown.
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  • 文章类型: Journal Article
    由于难以以高的选择性和效率定位适当的结构模板和聚合物接枝/生长策略,因此精确合成miktoarm星形聚合物(MSP)仍然是合成化学中的巨大挑战之一。在这里,~2nm金属有机多面体(MOPs),由间苯二甲酸(IPA)和Cu2+配位构建,作为模板,用于精确合成24臂MSP,因为它们具有独特的对数配体交换动力学。以IPA作为端基制备了六种不同的聚合物,它们进一步与Cu2配位,得到相应的24臂星形均聚物,分别。MSP可以通过在热退火时在溶液中混合目标同臂星形聚合物来获得。MSP的组成可以通过输入的星形聚合物混合物的配方容易地和精确地调节。有趣的是,所获得的MSP可以通过典型的溶剂萃取方案被分选成同臂星形聚合物。杂交和分选过程可以通过热退火和溶剂处理的循环可逆地进行。复杂的协调框架不仅为具有混合功能的MSP和MOP的轻松精确合成开辟了新的途径,而且还提供了设计可持续聚合物系统的能力。
    The precise synthesis of miktoarm star polymers (MSPs) remains one of the great challenges in synthetic chemistry due to the difficulty in locating appropriate structural templates and polymer grafting/growing strategies with high selectivity and efficiency. Herein, ≈2 nm metal-organic polyhedra (MOPs), constructed from the coordination of isophthalic acid (IPA) and Cu2+ , are applied as templates for the precise synthesis of 24-arm MSPs for their unique logarithmic ligand-exchange dynamics. Six different polymers are prepared with IPA as an end group and they further coordinated with Cu2+ to afford the corresponding 24-arm star homo-polymers. MSPs can be obtained by mixing targeted homo-arm star polymers in solutions upon thermal annealing. The compositions of MSPs can be facilely and precisely tuned by the recipe of the star polymer mixtures used. Interestingly, the obtained MSPs can be sorted into homo-arm star polymers through a typical solvent extraction procedure. The hybridization and sorting process can be reversibly conducted through the cycle of thermal annealing and solvent treatment. The complex coordination framework not only opens new avenues for the facile and precise synthesis of MSPs and MOPs with hybrid functionalities, but also provides the capability to design sustainable polymer systems.
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  • 文章类型: Journal Article
    金属有机多面体(MOP)的表面化学对其物理化学性质至关重要,因为它决定了它们如何与溶剂等外部物质相互作用。合成有机分子,金属离子,甚至是生物分子。因此,促进不同官能团结合到MOP表面上的合成方法的进步将显著拓宽MOP的性质范围和潜在应用。在这里,我们描述了铜(I)催化的使用,叠氮化物-炔环加成(CuAAC)点击反应以合成后修饰炔官能化的立方面体MOP的表面。为此,我们合成了具有24个可用表面炔烃基团的新型Rh(II)基MOP。我们已经证明,我们的“可点击的”Rh-MOP表面上的24种炔基可以在室温下与含叠氮化物的分子反应,不损害MOP的完整性。我们利用CuAAC点击化学的广泛底物目录和正交性质来密集地功能化具有不同官能团的MOP,包括聚合物,羧酸和膦酸,甚至生物素部分,一旦锚定到MOP的表面,它就保留了它们的识别能力。
    The surface chemistry of Metal-Organic Polyhedra (MOPs) is crucial to their physicochemical properties because it governs how they interact with external substances such as solvents, synthetic organic molecules, metal ions, and even biomolecules. Consequently, the advancement of synthetic methods that facilitate the incorporation of diverse functional groups onto MOP surfaces will significantly broaden the range of properties and potential applications for MOPs. This study describes the use of copper(I)-catalysed, azide-alkyne cycloaddition (CuAAC) click reactions to post-synthetically modify the surface of alkyne-functionalised cuboctahedral MOPs. To this end, a novel Rh(II)-based MOP with 24 available surface alkyne groups was synthesised. Each of the 24 alkyne groups on the surface of the \"clickable\" Rh-MOP can react with azide-containing molecules at room temperature, without compromising the integrity of the MOP. The wide substrate catalogue and orthogonal nature of CuAAC click chemistry was exploited to densely functionalise MOPs with diverse functional groups, including polymers, carboxylic and phosphonic acids, and even biotin moieties, which retained their recognition capabilities once anchored onto the surface of the MOP.
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  • 文章类型: Journal Article
    多孔液体(PL),多孔主体和大体积溶剂的总和赋予永久性空腔,是突出的新兴材料。尽管付出了巨大的努力,仍需要探索多孔主体和庞大的溶剂来开发新的PL系统。具有离散分子结构的金属有机多面体(MOP)可以被视为多孔主体;但是,其中许多是不可溶的实体。在这里,我们报告了通过调整不溶性MOP的表面刚度将III型PL转换为II型PL,Rh24L24,在年夜体积离子液体(IL)中。N-供体分子在Rh-Rh轴向位点上的官能化导致它们在大体积IL中的溶解,这赋予II型PL。实验和理论研究表明,按照笼孔,IL的体积较大,以及它们解散的原因。获得的PLs,捕获比纯溶剂更多的CO2,与单独的MOP和IL相比,已经描述了更高的CO2环加成催化活性。
    Porous liquids (PLs), a summation of porous hosts and bulky solvents bestowing permanent cavities, are the prominent emerging materials. Despite great efforts, exploration of porous hosts and bulky solvents is still needed to develop new PL systems. Metal-organic polyhedra (MOPs) with discrete molecular architectures can be considered as porous hosts; however, many of them are insoluble entities. Here we report the transformation of type III PL to type II PLs by tuning the surface rigidity of insoluble MOP, Rh24 L24 , in a bulky ionic liquid (IL). Functionalization of N-donor molecules on Rh-Rh axial sites ensue their solubilization in bulky IL which confer type II PLs. Experimental and theoretical studies reveal the bulkiness of IL as per the cage apertures, and the cause of their dissolution as well. The obtained PLs, capturing more CO2 than neat solvent, have depicted higher catalytic activity for CO2 cycloaddition compared to individual MOPs and IL.
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  • 文章类型: Journal Article
    光响应性共价有机框架(PCOFs)已成为吸附的有吸引力的候选物,但是,由于引入光敏基序和/或繁琐的后修饰步骤后,共价有机骨架(COF)的结构顺序丧失,因此构建PCOF吸附剂具有挑战性。这里,制定了一个简单的战略,通过将光敏金属-有机多面体(PMOP)分散到COF中,赋予COFs光响应吸附位点。作为一项概念验证研究,孔尺寸为4.5nm的COF和具有合适分子尺寸的PMOP(对于反式和顺式构型为4.0和3.1nm,分别)选择以满足适当住宿空间的要求,良好的客人分散,和自由异构化。在引入PMOP之后,COF的结构被很好地保留。有趣的是,所获得的光敏主客体复合(PHGC)吸附剂对丙烯(C3H6)具有光调节吸附能力,吸附能力的变化可达43.3%,并且在多个循环中稳定。密度泛函理论计算表明,可见光照射将PHGC中的偶氮苯基序驱动到反式构型,并且吸附位点完全打开并与C3H6相互作用。紫外光照射使偶氮苯基序转变为顺式构型,导致吸附位点的屏蔽和随之而来的C3H6的释放。
    Photoresponsive covalent organic frameworks (PCOFs) have emerged as attractive candidates for adsorption, but it is challenging to construct PCOF adsorbents due to structural order loss of covalent organic frameworks (COFs) after introducing photoresponsive motifs and/or tedious steps of postmodification. Here, a facile strategy is developed, by dispersing photoresponsive metal-organic polyhedra (PMOP) into COFs, to endow COFs with photoresponsive adsorption sites. As a proof-of-concept study, a COF with pore size of 4.5 nm and PMOP with suitable molecular size (4.0 and 3.1 nm for trans and cis configuration, respectively) are selected to meet the requirements of proper accommodation space, good guest dispersion, and free isomerization. The structure of COF is well preserved after introducing PMOPs. Interestingly, the obtained photoresponsive host-guest composite (PHGC) adsorbents exhibit photomodulated adsorption capacity on propylene (C3 H6 ) and the change in adsorption capacity can reach up to 43.3% and is stable during multiple cycles. Density functional theory calculations reveal that visible-light irradiation drives the azobenzene motifs in PHGCs to the trans configuration and the adsorption sites are fully open and interact with C3 H6 . UV-light irradiation makes the azobenzene motifs transform to the cis configuration, leading to the shield of the adsorption sites and the consequent release of C3 H6 .
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  • 文章类型: Journal Article
    使用富镍涂层对阴极进行表面改性可防止体积和表面降解,以使锂离子电池在高电压下稳定运行。然而,绝缘和致密的无机涂层通常阻碍电荷转移和离子扩散动力学。在这项研究中,提出了在锂离子电池的微孔单元内使用具有3D网络的金属有机多面体(MOP)制造双功能涂层材料,以实现表面稳定和容易的离子扩散。Zr基MOP通过引入酰基作为化学键(MOPAC)进行修饰,和MOPAC层通过简单的喷涂在阴极上均匀地涂覆。涂层允许电子和离子的平稳传输。MOPAC通过形成锂离子选择性钝化膜有效地抑制阴极和电解质之间的副反应并保护活性材料免受侵蚀性氟离子的影响。与原始和MOP涂覆的阴极相比,MOPAC涂覆的富镍层状阴极具有更好的循环保留和增强的动力学性能。还证实了通过MOPAC减少了阴极上不期望的气体析出。微孔MOPAC涂层可以同时稳定富镍层状阴极的本体和表面,并保持高性能锂离子电池良好的电化学反应动力学。
    Surface modification of cathodes using Ni-rich coating layers prevents bulk and surface degradation for the stable operation of Li-ion batteries at high voltages. However, insulating and dense inorganic coating layers often impede charge transfer and ion diffusion kinetics. In this study, the fabrication of dual functional coating materials using metal-organic polyhedra (MOP) with 3D networks within microporous units of Li-ion batteries for surface stabilization and facile ion diffusion is proposed. Zr-based MOP is modified by introducing acyl groups as a chemical linkage (MOPAC), and MOPAC layers are homogenously coated by simple spray coating on the cathode. The coating allow the smooth transport of electrons and ions. MOPAC effectively suppress side reactions between the cathode and electrolyte and protect active materials against aggressive fluoride ions by forming a Li-ion selective passivation film. The MOPAC-coated Ni-rich layered cathode exhibited better cycle retention and enhanced kinetic properties than pristine and MOP-coated cathodes. Reduction of undesirable gas evolution on the cathode by MOPAC is also verified. Microporous MOPAC coating can simultaneously stabilize both the bulk and surface of the Ni-rich layered cathode and maintain good electrochemical reaction kinetics for high-performance Li-ion batteries.
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  • 文章类型: Journal Article
    多孔液体是一种独特的液体介质,它将多孔固体的空腔与液体的流动性相结合。这种特殊的特性在各种应用中提供了潜力。在这里,我们报告了一种II型光敏多孔离子液体(PPIL),它溶解了光敏金属-有机多面体(PMOP,在聚乙二醇官能化的大离子液体(IL)中由双铜和含偶氮苯的羧酸盐构成)。由于有利的离子相互作用,庞大的IL分子包围PMOP之外,并保持内部空腔。偶氮苯部分可以在PPIL中自由异构化,以在可见光和UV光照射时暴露和遮蔽活性位点。因此,PPIL的吸附能力是通过光照控制的,与纯IL相比,CO2吸收的变化高达30%。该研究可能会激发由光调节而不是变压变温吸附的新吸附工艺的发展。
    A porous liquid is a unique liquid medium that combines the cavity of porous solids with the fluidity of liquids. This special characteristic offers potential in various applications. Here we report a type II photoresponsive porous ionic liquid (PPIL) from dissolving a photoresponsive metal-organic polyhedron (PMOP, constructed from dicopper and azobenzene-containing carboxylate) in a polyethylene-glycol-functionalized bulky ionic liquid (IL). Owing to favorable ion interactions, bulky IL molecules encircle outside PMOP, and the inter cavities are maintained. The azobenzene moieties can be isomerized freely in the PPILs to expose and shelter active sites upon visible and UV light irradiation. Hence, the adsorption capacity of PPILs is controllable by light irradiation, and the change in CO2 uptake is up to 30 % compared to neat IL. This study may inspire the development of new adsorption process regulated by light instead of pressure and temperature swing adsorption.
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  • 文章类型: Journal Article
    具有可逆和动态特性的配位驱动的交联网络在各种应用领域中获得越来越多的兴趣。在这里,我们使用配位交联方法,使用金属-有机多面体(MOP)作为高连接性构建块来后组装一类配位超交联MOP(CHMOP)聚合物。将12个连接的MOP节点引入聚合物网络对于生产克服机械性能和动态愈合之间的权衡的膜至关重要。同时拥有包括形状记忆在内的多功能,溶液可加工性,3D打印。CHMOP也可用于防腐涂层和实现功能联轴器,例如,形状记忆辅助自我修复(SMASH),这在基于MOP的杂化材料中还没有实现。这项工作不仅为构建新型多功能材料提供了可行的策略,而且极大地扩展了MOP的应用范围。
    Coordination-driven crosslinking networks with reversible and dynamic characteristics are gaining increasing interest in diverse application fields. Herein, we use a coordination crosslinking approach using metal-organic polyhedra (MOPs) as high-connectivity building blocks to post-assemble a class of coordination hypercrosslinked MOP (CHMOP) polymers. The introduction of 12-connected MOP nodes to the polymeric networks is critical to producing membranes that overcome the trade-off between mechanical properties and dynamic healing, and meanwhile possess multifunctionalities including shape memory, solution processability, and 3D printing. The CHMOPs can also be used for anticorrosion coating and achieve function couplings, e.g., shape memory-assisted self-healing (SMASH), which have not been achieved in the MOP-based hybrid materials yet. This work not only offers a feasible strategy to construct new multifunctional materials but also greatly expands the application scopes of MOPs.
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  • 文章类型: Journal Article
    金属基氧阴离子是潜在的有毒污染物,可能导致严重的水污染。因此,这种物种的隔离最近受到了重要的研究关注。尽管几种吸附剂已被用于化学品的有效管理,它们有限的微孔性质以及非整体适用性阻碍了它们的大规模实时应用。在这里,我们开发了一种独特的阴离子可交换杂化复合气凝胶材料(IPcomp-6),将稳定的阳离子金属有机多面体与分层多孔金属有机凝胶整合在一起。复合清除剂对各种有害的含氧阴离子表现出高度选择性和非常快的分离效率,例如,HAsO42-,SeO42-,ReO4-,CrO42-,MnO4-,在水中,在存在100倍过量的其他共存阴离子的情况下。该材料能够选择性地消除痕量HAsO42-,即使浓度很低,远低于WHO定义的饮用水中的AsV限值。
    Metal-based oxoanions are potentially toxic pollutants that can cause serious water pollution. Therefore, the segregation of such species has recently received significant research attention. Even though several adsorbents have been employed for effective management of chemicals, their limited microporous nature along with non-monolithic applicability has thwarted their large-scale real-time application. Herein, we developed a unique anion exchangeable hybrid composite aerogel material (IPcomp-6), integrating a stable cationic metal-organic polyhedron with a hierarchically porous metal-organic gel. The composite scavenger demonstrated a highly selective and very fast segregation efficiency for various hazardous oxoanions such as, HAsO4 2- , SeO4 2- , ReO4 - , CrO4 2- , MnO4 - , in water, in the presence of 100-fold excess of other coexisting anions. The material was able to selectively eliminate trace HAsO4 2- even at low concentration to well below the AsV limit in drinking water defined by WHO.
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