Supramolecular Self-Assembled Ligands in Asymmetric Transition Metal Catalysis

The design of novel chiral ligands is at the core of asymmetric catalysis. The catalytic characteristics of a transition metal catalyst such as activity, selectivity and stability can be fine-tuned by optimization of the steric and electronic properties of the coordinating ligands. In asymmetric transformations, catalyst optimization still relies to a large extent on trial-and-error and educated guesses. New strategies based on combinatorial screening and high-throughput experimentation have been introduced for the design and optimization of new ligands and catalytic systems. Supramolecular bidentate ligands that form by self-assembly of building blocks are particularly suited for this combinatorial approach as the potential number of catalysts grows exponentially with the number of building blocks synthesized. Catalytic systems based on supramolecular interactions have proven to be highly advantageous in creating large ligand libraries for high-throughput screening, which allows optimization of activity and selectivity for a variety of reactions. In this review we describe the progress in this field.     

高通量筛选技术在多相催化研究中的应用

通过对组合催化研究的关键因素－－催化剂高通量筛选技术的评价分析认为：在对已有的催化体系和催化剂优化的同时，如何高校研制开发新筛选检测技术，诸如反应器设计和检测器的选择，是组合催化研究的主导思想，对此的深刻理解和运用将增强实验室的创新能力。     

Efficient discovery and optimization of complex high-throughput experiments

As the pace of experimentation in materials science and catalysis has increased, experimental tactics and strategies have had to adapt to meet the demands of goals of experimentalists, and the spaces they explore. This pace has increased from runs/year to runs/day and sometimes to runs/minute in high-throughput experimentation. Although much of this capacity is used to simply speed up conventional experimental designs, the leading-edge application is discovery of low-probability, high-value occurrences (hits) by searching extensive, complex experimental spaces. Conventional design of experiments (DoE) is not capable of dealing with these issues. Instead, more advanced experimental tactics and strategies must be implemented. After introducing the elements that make an experimental campaign complex, here we present a novel statistical model-based evolutionary experimental strategy and apply it to the optimization of a family of artificial complex systems. With our experiments, we show that such a strategy may significantly reduce the experimental effort required for finding the optima compared to other state-of-the-art evolutionary strategies.     

High-throughput preparation and screening of rhenium oxide-alumina catalysts in olefin metathesis

High-throughput (HT) experimentation in heterogeneous catalysis exemplifies a multidisciplinary approach to address in an efficient manner different aspects of catalyst development – from synthesis to testing and characterization. The present work reports on preparation systems for rapid parallel synthesis of well defined heterogeneous catalysts and catalyst screening in olefin metathesis. Metathesis of ethene and but-2-ene to propene was chosen as a test reaction. The influences of various parameters such as rhenium oxide loading, catalyst calcination conditions, catalyst pre-treatment, as well as the reaction temperature and contact time on the catalytic performance are discussed. Sample characterization by UV–vis and FT-IR gave an evidence for the formation of active surface perrhenate species, very sensitive to humidity and pre-treatment conditions applied.     

Experimental strategies for combinatorial and high-throughput materials development

As high-throughput experimental techniques have become common in the area of materials research, entirely new types of experimental strategies have appeared. The kinds of problems, the desired outcomes, and the appropriate patterns are significantly different from those associated with conventional experimentation. Classical experimental design (design of experiments, DOE) strategies grew up in a period of slow, laborious, error-prone experimentation; a modern high-throughput laboratory can test more materials in a week than was previously done in a year. The goal of this Account is to identify and critically discuss some of the strategies that are being developed and used in this new, exciting area of research.     

负载液相催化剂的研究进展

负载液相催化剂是一种新型的“混合型”催化剂，它结合了均相催化高活性、高选择性和多相催化接触面积大、容易分离的优点，有广阔的应用前景。综述了迄今为止关于负载液相催化剂的研究进展，总结了负载液相催化剂的特点及其在许多重要化学反应中的应用。     

New Paradigms and Future Critical Directions in Heterogeneous Catalysis and Multifunctional Reactors

Heterogeneous catalysis is a key pillar of the global industrial chemical and petrochemical sector, and 85% of all chemical products are produced with at least one catalytic step. Indeed, catalysis and catalytic reactors are a critical underpinning science for energy, environmental, and economic security. This paper reviews some future critical directions for research in catalysis science, toward a greener and more sustainable future. We believe that even a relatively mature field as heterogeneous catalysis and nanomaterials can be vitalized and spurred by major discoveries, but an outside-the-box thinking and a focused effort in a large plurality of disciplines is necessary. Thus, critical research needs in several areas, including heterogeneous and homogeneous catalysis, biocatalysis, photocatalysis, electrochemical conversions, and computational catalysis, are reviewed. The research needs of the future lie at the intersection of synthesis of novel nanostructured materials with tunable pore size distribution, controlled porosity, and high surface area; development of new catalytic applications for such materials; and the science of advanced characterization including in situ spatiotemporal analysis. In the area of computational catalysis, we believe that the future lies in the development of hybrid methods (parallel and serial) which can model the typical multiscale phenomena that are typically encountered in protein translocation and signal transduction, charge transport, enzymatic catalysis, surface chemistry, and self-assembly in complex fluids. As we promulgate the new directions to the catalysis fraternity, some prior research areas will unfortunately need to be relegated to obsolescence, to maintain a healthy balance on the research forefront.     

离子液体/有机两相催化应用研究进展

作者就近年来离子液体/有机两相催化在加氢、氢甲酰化、齐聚、Heck反应和羰基化反应中的研究进展进行了综述,重点介绍了基于氟硼酸根(BF4-)或氟磷酸根(PF6 -)的咪唑类离子液体在均相催化反应中的应用,并对离子液体/有机两相催化工业应用的前景进行了探讨.     

Asymmetric Counteranion-Directed Catalysis (ACDC): A Remarkably General Approach to Enantioselective Synthesis

Asymmetric counteranion-directed catalysis (ACDC) is a powerful new concept, which can potentially be used to achieve enantioselectivity in any type of reaction proceeding through positively charged intermediates. It has already been applied in different areas of catalysis, such as organocatalysis, transition-metal catalysis, and Lewis acid catalysis. Due to its complementarity with traditional approaches to achieve enantioselection, ACDC holds special promise for long-standing challenges from all areas of catalysis, where matched cases can be designed. ACDC also represents a new way of thinking during method development, which could be of help to chemists from a variety of research areas.     

液态醇催化氧化制醛或酮的研究进展

对液态醇催化氧化制醛或酮按照均相催化、液固多相催化和有机相－水相两相催化、催化剂分金属类别进行了回顾，认为液固多相催化剂和有机相－水相两相催化有着诱人的发展前景。     

Kinetics of glucose decomposition in formic acid

Cellulose is abundantly available in the form of forestry and agricultural lignocellulosic residues. These residues offer the most potential source for the production of cellulosic glucose, which is a prerequisite for the sustainable production of glucose-based fuels and chemicals. Acid catalysis is one path to lignocellulosic glucose and further to its dehydration end products. Furthermore, many studied lignocellulose pretreatment methods for enzymatic hydrolysis are carried out in acidic conditions, in which the unwanted release of hemicellulose-based glucose and its further reactions to harmful end products are possible. Thus, in order to maximize glucose production from non-food cellulosic raw materials, data on the kinetics of cellulose decomposition and formation rates of end products are required. Glucose decomposition is a complex reaction system that has often been modelled with empirical, simplified models. In this study, a kinetic model was developed for glucose decomposition in formic acid solution. The experimentation was carried out in batch reactors at 180-220 °C in 5-20% (w/w) formic acid. The model developed relies on a mechanistic step through an unknown substance and gives excellent correspondence to the experimental data despite the pseudo-elementary nature of the model structure.     

硫基烯烃的合成新方法

硫基烯烃是具有一定活性的烯类化合物,介绍了硫基烯烃的合成新方法——金属络合物催化法和碱催化法。金属络合物催化和碱催化的含硫化合物与炔烃反应可生成立体选择性、高效性产物,是近年来研究催化法的热点,为碳-硫的构建提供了有效途径。     

绿色化学中的新催化方法

本文简述了绿色化学中几种有前景的新催化方法，包括固体酸取代液体酸的酸催化，晶格氧代替分子氧的氧化，TS－1分子筛H2O2的清洁氧化新工艺及羰化催化的新发展。     

表面活性剂在化学催化中的应用

表面活性剂催化化学反应过程的机理有胶束催化和相转移催化.分析总结了在不同条件下表面活性剂在化学催化中的应用.胶束催化效率高,易于控制,成为模拟酶催化的最佳体系;相转移催化产物纯度高,反应转化率高,目的产物的专一性增加,用于合成化学获得了很高的评价.     

Structure oriented library design in gas phase oxidation catalysis

Structure oriented screening techniques are discussed with regard to their usefulness and applicability in catalyst screening in research projects with different degrees of exploratory character. Structure oriented screening approaches were applied to build libraries for two target reactions in two case studies presented in this paper one challenging exploratory ammon-oxidation reaction for the conversion of C₆-feedstocks to adipodinitrile precursors with currently no relevant useful materials and no technical solution known. In this study the structure driven approach helped to identify lead structures for the conversion. The second case study focuses on the oxidation of acrolein and methacrolein to the corresponding unsaturated acids. Here technical catalyst candidate materials are known and are applied in the actual industrial applications. Therefore, the focus of the second case study is to find a superior material or alternative candidate materials with improved properties with this research strategy. For both case studies the effectiveness of the structure based approach is evaluated and put into perspective with state of the art library design and research strategies in high throughput experimentation and combinatorial catalysis.     

Catalysis and Alternatives to Liquid Fuels

The refining of liquid fuels from petroleum has arguably had a larger effect on the field of (non-enzymic) catalysis than any other industry, so much so that both the engineering and social norms resulting from, and supporting the petroleum industry now affects both the agenda and problem-setting goals in the alternative fuels industry and consequentially in catalysis. For example, there is great emphasis today on the development of biofuels that resemble in their properties and operation gasoline and diesel. I argue that this is not necessarily the most prudent manner of using biomass as a fuel source and propose that it is more prudent and efficient to convert biomass to electricity directly. If adopted, this would have a vast effect on vehicle design, on electrical distribution strategies and investments and consequently on the pathways that research programs in catalysis are likely to follow, replacing current emphases on producing and improving liquid fuels with ones affecting such processes as combustion, and battery and other electrical storage and distribution issues.     

催化氢酯基化反应的研究进展

介绍了氢酯基化反应及其特点，分别综述了均相催化氢酯基化反应和多相催化氢酯基化反应的研究现状，并对不对称催化氢酯基化的研究提出了建议。     

Design and Synthesis of New Pyrazole-Based Heterotricycles and their Derivatization by Automated Library Synthesis

Small-molecule heterocycles bearing orthogonal functionality have the potential to deliver diverse structural motifs that aid the drug-discovery effort. This work highlights how a readily assembled N-hydroxyethyl pyrazole trifluoroborate offers rapid access to architecturally distinct 5-6-6- and 5-7-6-fused tricyclic compounds. This chemistry is not only amenable to single compound synthesis, but also to high-throughput experimentation. It gives easy access to diverse compound arrays with various physicochemical and ADME profiles by fully automated library synthesis. The combination of the high-throughput experimentation with rapid testing of the compounds in an integrated physicochemical and ADME profiling workflow allows accelerated design of novel lead compounds in drug-discovery projects.     

用于TS-1催化苯酚羟基化的一体式催化/膜过滤系统的模型研究

This research is focused on the development of a simple design model of the submerged catalysis/ membrane filtration (catalysis/MF) system for phenol hydroxylation over TS-1 based on the material balance of the phenol under steady state and the reported kinetic studies. Based on the developed model, the theoretical phenol conversions at steady state could be calculated using the kinetic parameters obtained from the previous batch ex-periments. The theoretical conversions are in good agreement with the experimental data obtained in the submerged catalysis/MF system within relative error of ±5%. The model can be used to determine the optimal experimental conditions to carry out the phenol hydroxylation over TS-1 in the submerged catalysis/MF system.