Continuous flow hydrosilylation in SILP/scCO2 systems - an innovative approach to reduction andfunctionalization of alkynes, imines and carbonyl compounds

该项目的目标是设计，评估和演示连续流催化氢化硅烷化的方法，分子轴承C = C，C=O和C=N键。为此，将开发包含稳定化和固定化在负载型离子液体相（SILP）中或磷钨酸（PTA）/氧化铝（Alox）载体上的分子催化剂或催化活性纳米颗粒的催化体系。通过使用具有手性配体的分子催化剂，也设想了立体选择性版本。在SILP-scCO 2方法中，超临界二氧化碳（scCO 2）将用作移动的相以将底物输送到含有催化剂的SILP基质中，并同时提取产物用于分离。这种方法从scCO 2的气体样传输和液体样溶解度特性中获益。由于有机硅化合物在压缩二氧化碳中的高溶解度和SILP材料在相同介质中的可忽略溶解度，该方法特别适合于设想的应用。在（PTA）/Alox方法的情况下，根据底物/产物的性质，将使用纯试剂、scCO 2或常规溶剂来实现流动。这项研究将提供基础知识的组合ofcatalysis与先进的流体，从而有助于在理解，控制和掌握的连续流过程中的一般进展，在三个不同的，但强烈相互关联的，过程水平：-分子尺度：如何催化活性金属络合物和集群的分子相互作用与固定化矩阵影响其性能的短期和长期？-中尺度：催化剂、底物和产物的物理化学性质如何与固定相和移动的相协调，以及如何与设计的反应和分离集成策略协调？宏观尺度：如何设计和建造紧凑的连续流装置，以实现设计的反应/分离方法，并允许反应和催化剂监测？这三个层次的开发，重点是相互兼容性将导致一个新的可持续的方法，催化有机硅化学导致高生产率和改善，甚至新的选择性。使用scCO 2作为良性传输介质的流动化学与有效的催化剂固定化程序的组合将确保无金属和无溶剂的产物分离，从而减少任何额外的繁琐或材料密集的后处理程序。我们的目标是一个灵活的方法，使连续流动硅氢加成的各种炔和羰基化合物与微小的操作调整。

The goal of the project is to design, evaluate, and demonstrate methods for continuous-flow catalytic hydrosilylation of molecules bearing C≡C, C=O and C=N bonds. For this purpose, catalytic systems comprising molecular catalysts or catalytically active nanoparticles stabilized and immobilized in a supported ionic liquid phase (SILP) or on Phosphotungstic Acid (PTA)/aluminum oxide (Alox) supports will be developed. Stereoselective versions are envisaged too by using molecular catalysts with chiral ligands. In the SILP-scCO2 approach, supercritical carbon dioxide (scCO2) will be used as a mobile phase to transport substrates into the catalyst containing SILP matrix and simultaneously extract the products for isolation. This methodology takes advantagefrom the gas-like transport and liquid-like solubility properties of scCO2. Thanks to the high solubility of organosilicon compounds in compressed carbon dioxide and the negligible solubility of the SILP materials in the same medium, this approach is particularly suited for the envisaged application. In the case of the (PTA)/Alox approach, the use of neat reagents, scCO2 or conventional solvents will be used to realize the flow depending on the nature of the substrates/products. This study will provide fundamental knowledge on the combination ofcatalysis with advanced fluids, thus contributing to a general progress in the understanding,control, and mastering of continuous-flow processes at the three different, yet stronglyinterconnected, process levels:- Molecular scale: How do the molecular interactions of catalytically active metal complexes and clusters with the immobilization matrix affect their performance on the short and on the long term?- Mesoscale: How do the physico-chemical properties of the catalyst, subtrates andproducts harmonize with the stationary and mobile phase and, in general, with the devised strategy for integrating reaction and separation?- Macroscale: How should a compact continuous-flow setup be designed and constructed to implement the devised reaction/separation approach and to allow both reaction and catalyst monitoring?The exploitation of these three levels with a focus on mutual compatibility will result in a new sustainable approach for catalytic organosilicon chemistry leading to high productivities and improved or even novel selectivities. The combination of flow-chemistry using scCO2 as benign transport medium with an effective catalyst immobilization procedure will ensure metal-free and solvent-free product isolation, thus cutting down any additional tedious or material intensive workup procedures. We aim at a flexible methodology enabling the continuous flow hydrosilylation of various alkynes and carbonyl compounds with minor operational adjustments.