Soluble metal-oxide frameworks: Transport of large organic guests through smaller subnanoscale pores and the effects of nano-confinement on hydrophobic self-assembly and organic reactions

可溶性金属氧化物框架：通过较小的亚纳米级孔传输大的有机客体以及纳米限制对疏水自组装和有机反应的影响

• 批准号: 186966117
• 负责人: Professor Dr. Achim Müller
• 金额: --
• 依托单位: Department of Chemistry
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2014-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/186966117?language=en
• 关键词: Soluble; metal; oxide; frameworks; Transport

In zeolites and rigid functional materials, substrates whose sizes exceed those of the pore dimensions are rigorously excluded. Meanwhile, cavities within flexible metal-organic frameworks (MOFs; another class of porous solid-state structures) can accommodate substrates by reversible, stepwise structural expansion (“breathing”). Now, using a “capsule”-like molybdenum-oxide-based framework as a soluble analog of porous solid-state (rigid) oxides, we recently reported a new phenomenon: the passage of branched-alkane “guests” through flexible sub-nanometer Mo9O9 apertures whose geometrical diameters are smaller than the entering species (“Flexible Pores of a Metal-Oxide-Based Capsule Permit Entry of Comparatively Larger Organic Guests” J. Am. Chem. Soc., 2009, 131, 6380-6382). This new phenomenon likely reflects the greater flexibility of molecular versus solid-state structures, and represents a distinct departure from traditional models for diffusion through rigid porous solid-oxides. The immediate goal of proposed research is to investigate the fundamental mechanism(s) responsible for the uptake of large guests by comparatively smaller metal-oxide pores. The next objective is to use the metal-oxide capsules as “nano-reactors” for catalytic accelerations of reaction rates through the templating effects of proximal binding, and/or hydrophobic self-assembly within the capsule’s nano-confined interiors. In all the above, the metal-oxide frameworks will be deployed as molecular analogs for porous solid-state metal oxides, whose reactions and their mechanisms can now be studied in detail by solution-state methods.

在沸石和刚性功能材料中，严格排除尺寸超过孔尺寸的基材。同时，柔性金属有机框架（MOF;另一类多孔固态结构）内的空腔可以通过可逆的、逐步的结构膨胀（“呼吸”）来容纳基底。现在，使用“胶囊”样的氧化物基的框架作为多孔固态（刚性）氧化物的可溶性类似物，我们最近报道了一种新现象：支链烷烃“客体”通过柔性亚纳米Mo 9 O 9孔，其几何直径小于进入的物质（“Flexible Pores of a Metal-Oxide-Based Permit Capsule Entry of Comparatively Larger Organic Guests”J. Am.化学会，2009，131，6380-6382）。这种新的现象可能反映了分子结构相对于固态结构的更大灵活性，并且代表了与通过刚性多孔固体氧化物扩散的传统模型的明显偏离。拟议的研究的直接目标是调查的基本机制（S）负责的相对较小的金属氧化物孔的大客人的吸收。下一个目标是使用金属氧化物胶囊作为“纳米反应器”，通过近端结合的模板效应和/或胶囊的纳米限制内部的疏水自组装来催化加速反应速率。在所有上述情况下，金属氧化物框架将被部署为多孔固态金属氧化物的分子类似物，其反应及其机制现在可以通过溶液状态方法详细研究。

项目成果

Catalysis in a porous molecular capsule: activation by regulated access to sixty metal centers spanning a truncated icosahedron.

• DOI: 10.1021/ja304513t
• 发表时间: 2012-07
• 期刊: Journal of the American Chemical Society
• 影响因子: 15
• 作者: Sivil Kopilevich;A. Gil;M. Garcia-Ratés;J. Bonet-Ávalos;C. Bo;A. Müller;I. Weinstock