SusChEM: Metal Organic Nanoparticles (MONPs) for Supramolecularly Assisted Covalent Assembly

许多重要的有机化合物，包括药剂，都是从更简单的商业材料中制备的。这些有机化合物的合成通常需要几个步骤，其中一些步骤涉及金属基催化剂。开发出产率更高并在水中运行的催化剂，既减少了挥发性有机溶剂的使用量，也减少了重金属废物，从而使这些合成过程更可持续。在美国国家科学基金会化学部大分子、超分子和纳米化学项目的支持下，伊利诺伊大学厄巴纳-香槟分校的Steven C.Zimmerman教授正在开发纳米级聚合物基金属催化剂，这种催化剂可以在水中执行此类反应，由于其毒性低，甚至可以在人体细胞中执行。因此，这项工作的一个更广泛的影响是创造了一个纳米级的机器人，一个“纳米机器人”，它选择性地进入某些类型的细胞，并从更小的、细胞渗透的、但不活跃的小分子中制备生物活性物质。另一个更广泛的影响是培养了一批不同的本科生和研究生。伊利诺伊大学的研究团队正在开发新的聚合催化剂，这种催化剂是通过开环复分解聚合制备的，可以扩展所进行的反应类型。优化的金属-有机聚合物纳米颗粒(MONPs)被设计用于催化铜辅助的“点击”反应、钯催化的Suzuki-Miyaura偶联反应和Ru介导的关环歧化反应。这些MONPs的疏水内部被设计为通过利用纳米粒子的疏水内部的优势，允许反应在低浓度的催化剂的水中进行。努力的方向是制备包含两个不同催化中心的MONPs，以允许发生连续的、正交的过程，增加MONP方法的复杂性和威力。最后，一种使用疏水结合以模块方式结合金属催化剂的ONP正在被作为一种更通用的即插即用策略而被追寻。

A wide range of important organic compounds, including pharmaceutical agents, are prepared from simpler, commercially available materials. The synthesis of these organic compounds often takes several steps, some of which involve metal-based catalysts. Developing catalysts that give higher yields and operate in water reduces both the amount of volatile organic solvents used and the heavy metal waste, thus, making these synthetic processes more sustainable. With the support from the Macromolecular, Supramolecular and Nanochemistry Program of the NSF Chemistry Division, Prof. Steven C. Zimmerman at the University of Illinois at Urbana-Champaign is developing nanoscale, polymer-based metal catalysts that can perform such reactions in water and, because of their low toxicity, even in human cells. Thus, a broader impact of the work is the creation of a nanoscale robot, a "nanobot" that selectively enter certain types of cells and prepare bioactive agents from smaller, cell-permeable, but inactive small molecules. Another broader impact is the training of a diverse group of undergraduate and graduate students.The research team at the University of Illinois is developing new polymeric catalysts, prepared by ring-opening metathesis polymerization, that expand the types of reactions performed. Optimized metal-organic polymeric nanoparticles (MONPs) are designed to catalyze the copper-assisted "click" reaction, the palladium-catalyzed Suzuki-Miyaura coupling reaction, and the ruthenium-mediated ring-closing metathesis reaction. The hydrophobic interior of these MONPs is designed to allow the reactions to proceed in water at low concentrations of catalyst by taking advantage of the hydrophobic interior of the nanoparticles. Efforts are directed toward the preparation of MONPs that contain two different catalytic centers to allow sequential, orthogonal processes to occur, increasing the complexity and power of the MONP approach. Finally, an ONP that modularly binds metal catalysts using hydrophobic binding is being pursued as a more universal, plug-and-play strategy.