Xinjiang Cui

Bio: Xinjiang Cui is an academic researcher from Chinese Academy of Sciences. The author has contributed to research in topics: Catalysis & Alkylation. The author has an hindex of 27, co-authored 91 publications receiving 3471 citations. Previous affiliations of Xinjiang Cui include Leibniz Institute for Neurobiology & University of Rostock.

Bridging homogeneous and heterogeneous catalysis by heterogeneous single-metal-site catalysts

Abstract: In heterogeneous single-metal-site catalysts (HSMSCs) the active metal centres are located individually on a support and are stabilized by neighbouring surface atoms such as nitrogen, oxygen or sulfur. Modern characterization techniques allow the identification of these individual metal atoms on a given support, and the resulting materials are often referred as single-atom catalysts. Their electronic properties and catalytic activity are tuned by the interaction between the central metal and the neighbouring surface atoms, and their atomically dispersed nature allows for metal utilization of up to 100%. In this way, HSMSCs provide new opportunities for catalysis, and with respect to structure build a bridge between homogeneous and heterogeneous catalysis. Herein, selected publications from 2010 in this area are reviewed and their perspectives for the near future are highlighted. Where appropriate, comparisons between HSMSCs and homogeneous/heterogeneous counterparts are presented. Single-atom catalysts have drawn increasing attention as methods for their preparation and characterization improve. Here, Beller and co-workers discuss the latest developments in the field of single-metal-site catalysts, discussing how this catalyst class bridges heterogeneous and homogeneous catalysis, and providing a perspective on how the field might continue to develop.

Nano-Gold Catalysis in Fine Chemical Synthesis

Abstract: the National Natural Science Foundation of China (21073208);the Chinese Academy of Sciences

Synthesis and Characterization of Iron–Nitrogen-Doped Graphene/Core–Shell Catalysts: Efficient Oxidative Dehydrogenation of N-Heterocycles

Abstract: An important goal for nanocatalysis is the development of flexible and efficient methods for preparing active and stable core–shell catalysts. In this respect, we present the synthesis and characterization of iron oxides surrounded by nitrogen-doped-graphene shells immobilized on carbon support (labeled FeOx@NGr–C). Active catalytic materials are obtained in a simple, scalable and two-step method via pyrolysis of iron acetate and phenanthroline and subsequent selective leaching. The optimized FeOx@NGr–C catalyst showed high activity in oxidative dehydrogenations of several N-heterocycles. The utility of this benign methodology is demonstrated by the synthesis of pharmaceutically relevant quinolines. In addition, mechanistic studies prove that the reaction progresses via superoxide radical anions (·O2–).

Utilization of CO2 as a C1 Building Block for Catalytic Methylation Reactions

Abstract: Developing new synthetic approaches for benign CO2 utilization is of current interest. In this respect, reductive alkylations using N- or C-based nucleophiles to give the corresponding methyl amines and (hetero)arenes are investigated intensively. Crucial points for such benign methylations are the choice of suitable homogeneous or heterogeneous catalyst systems. In this article, selective activation of the substrates and the use of acidic cocatalysts are highlighted.

Highly selective hydrogenation of arenes using nanostructured ruthenium catalysts modified with a carbon-nitrogen matrix.

Abstract: Selective hydrogenations of (hetero)arenes represent essential processes in the chemical industry, especially for the production of polymer intermediates and a multitude of fine chemicals. Herein, we describe a new type of well-dispersed Ru nanoparticles supported on a nitrogen-doped carbon material obtained from ruthenium chloride and dicyanamide in a facile and scalable method. These novel catalysts are stable and display both excellent activity and selectivity in the hydrogenation of aromatic ethers, phenols as well as other functionalized substrates to the corresponding alicyclic reaction products. Furthermore, reduction of the aromatic core is preferred over hydrogenolysis of the C–O bond in the case of ether substrates. The selective hydrogenation of biomass-derived arenes, such as lignin building blocks, plays a pivotal role in the exploitation of novel sustainable feedstocks for chemical production and represents a notoriously difficult transformation up to now. The selective reduction of arenes is important in organic synthesis and also valorization of biomass. Here, the authors report the use of ruthenium-based nanoparticles, which display high activity in arene reduction and preferentially hydrogenate aromatic rings rather than cleaving etheric C-O bonds.

Using carbon dioxide as a building block in organic synthesis

Abstract: Carbon dioxide exits in the atmosphere and is produced by the combustion of fossil fuels, the fermentation of sugars and the respiration of all living organisms. An active goal in organic synthesis is to take this carbon--trapped in a waste product--and re-use it to build useful chemicals. Recent advances in organometallic chemistry and catalysis provide effective means for the chemical transformation of CO₂ and its incorporation into synthetic organic molecules under mild conditions. Such a use of carbon dioxide as a renewable one-carbon (C1) building block in organic synthesis could contribute to a more sustainable use of resources.

Sustainable Conversion of Carbon Dioxide: An Integrated Review of Catalysis and Life Cycle Assessment

Abstract: CO2 conversion covers a wide range of possible application areas from fuels to bulk and commodity chemicals and even to specialty products with biological activity such as pharmaceuticals. In the present review, we discuss selected examples in these areas in a combined analysis of the state-of-the-art of synthetic methodologies and processes with their life cycle assessment. Thereby, we attempted to assess the potential to reduce the environmental footprint in these application fields relative to the current petrochemical value chain. This analysis and discussion differs significantly from a viewpoint on CO2 utilization as a measure for global CO2 mitigation. Whereas the latter focuses on reducing the end-of-pipe problem “CO2 emissions” from todays’ industries, the approach taken here tries to identify opportunities by exploiting a novel feedstock that avoids the utilization of fossil resource in transition toward more sustainable future production. Thus, the motivation to develop CO2-based chemistry does...