4.3. Reaction Mechanism 2373 4.4. Asymmetric Synthesis 2374 4.5. Outlook 2374 5. Alternating Polymerization of Oxiranes and CO2 2374 5.1. Reaction Outlines 2374 5.2. Catalyst 2376 5.3. Asymmetric Polymerization 2377 5.4. Immobilized Catalysts 2377 6. Synthesis of Urea and Urethane Derivatives 2378 7. Synthesis of Carboxylic Acid 2379 8. Synthesis of Esters and Lactones 2380 9. Synthesis of Isocyanates 2382 10. Hydrogenation and Hydroformylation, and Alcohol Homologation 2382

Transformation of carbon dioxide.

Making plastics from carbon dioxide: salen metal complexes as catalysts for the production of polycarbonates from epoxides and CO2.

A plethora of methods have been developed over the years so that carbon dioxide can be used as a reactant in organic synthesis. Given the abundance of this compound, its utilization in synthetic chemistry, particularly on an industrial scale, is still at a rather low level. In the last 35 years, considerable research has been performed to find catalytic routes to transform CO(2) into carboxylic acids, esters, lactones, and polymers in an economic way. This Review presents an overview of the available homogeneous catalytic routes that use carbon dioxide as a C(1) carbon source for the synthesis of industrial products as well as fine chemicals.

Transformation of Carbon Dioxide with Homogeneous Transition-Metal Catalysts: A Molecular Solution to a Global Challenge?

https://eprints.ncl.ac.uk/file_store/production/162122/B5324BA5-F503-4BE9-947E-6F7ED01AAD04.pdf

Synthesis of cyclic carbonates from epoxides and CO2

It is well known that urbanization and industrialization have resulted in the rapidly increasing emissions of volatile organic compounds (VOCs), which are a major contributor to the formation of secondary pollutants (e.g., tropospheric ozone, PAN (peroxyacetyl nitrate), and secondary organic aerosols) and photochemical smog. The emission of these pollutants has led to a large decline in air quality in numerous regions around the world, which has ultimately led to concerns regarding their impact on human health and general well-being. Catalytic oxidation is regarded as one of the most promising strategies for VOC removal from industrial waste streams. This Review systematically documents the progresses and developments made in the understanding and design of heterogeneous catalysts for VOC oxidation over the past two decades. It addresses in detail how catalytic performance is often drastically affected by the pollutant sources and reaction conditions. It also highlights the primary routes for catalyst deactivation and discusses protocols for their subsequent reactivation. Kinetic models and proposed oxidation mechanisms for representative VOCs are also provided. Typical catalytic reactors and oxidizers for industrial VOC destruction are further discussed. We believe that this Review will provide a great foundation and reference point for future design and development in this field.

/pdf/recent-advances-in-the-catalytic-oxidation-of-volatile-zw2c35dbg7.pdf

Recent Advances in the Catalytic Oxidation of Volatile Organic Compounds: A Review Based on Pollutant Sorts and Sources.

Chemical fixation of carbon dioxide to cyclic carbonates proceeds effectively under extremely mild temperature and pressure by using a bifunctional nucleophile–electrophile catalyst system of tetradentate Schiff-base aluminum complexes ((Salen)AlX) in conjunction with a quaternary ammonium salt (n-Bu4NY) in the absence of any organic solvent. Electrophilicity of central Al3+ ion and the steric factor of substituent groups on the aromatic rings of (Salen)AlX (electrophile), and nucleophilicity and leaving ability of the anion Y− of n-Bu4NY (nucleophile) have a great effect on the catalytic activity of the bifunctional catalyst.

Chemical fixation of carbon dioxide to cyclic carbonates under extremely mild conditions with highly active bifunctional catalysts

Insight into the mesoporous FexCe1−xO2−δ catalysts for selective catalytic reduction of NO with NH3: Regulable structure and activity

The selective catalytic oxidation of ammonia to nitrogen (NH 3 -SCO) has been studied over CuO-CeO 2 mixed oxides. The active Cu component was doped into the CeO 2 by surfactant-templated method. The finely dispersed CuO, Cu-O-Ce solid solution and bulk CuO species were detected in CuO-CeO 2 mixed oxides. When the Cu loading was 10 wt% and the calcination temperature was 500 °C, CuO-CeO 2 catalyst exhibited the highest molar ratio of the finely dispersed CuO species and the smallest CeO 2 particles in size, and simultaneously possessed the highest level of activity. The finely dispersed CuO species was the main adsorbed sites of NH 3 molecules, and the NH 3(ad) could be further activated and transformed into NH x species by ceria under the roles of quick change of chemical state in near-surface region and the strong electron state interaction in CuO-CeO 2 catalysts. The synergetic interaction between the two components played an important role in NH 3 activation and oxidation. In addition, the activated intermediates (NH x ) could also react with lattice oxygen provided by Cu-O-Ce solid solution to form N 2 , N 2 O and H 2 O, which was confirmed by XPS, EPR and NH 3 -TPR analysis. Moreover, gas oxygen could refill the oxygen vacancies to replenish the lattice oxygen consumed by NH x species. The Cu-O-Ce solid solution promoted the activation of gas oxygen as well as the formation and migration of lattice oxygen in NH 3 -SCO reaction, and the formed rapid reduction–oxidation cycle was essential for the higher activity of NH 3 oxidation.

Selective catalytic oxidation of ammonia to nitrogen over CuO-CeO2 mixed oxides prepared by surfactant-templated method

Highly active electrophile–nucleophile catalyst system for the cycloaddition of CO2 to epoxides at ambient temperature

Novel iron–tungsten catalysts were first developed for the selective catalytic reduction of NOx by NH3 in diesel exhaust, achieving an excellent performance with a wide operating temperature window above 90% NOx conversion from 225 or 250 to 450 °C (GHSVs of 30 000 or 50 000 h–1). It also exhibited a pronounced stability and relatively high NOx conversion in the presence of H2O, SO2 and CO2. The introduction of W resulted in the formation of α-Fe2O3 and FeWO4 species obtained by HRTEM directly. The synergic effect of two species contributed to the high SCR activity, because of the increased surface acidity and electronic property. The FeWO4 with octahedral [FeO6]/[WO6] structure acted as the Bronsted acid sites to form highly active NH4+ species. Combining DFT calculations with XPS and UV–vis results, it was found that the fine electron interaction between α-Fe2O3 and FeWO4 made the electron more easily transfer from W6+ sites to Fe3+ sites, which promoted the formation of NO2. Judging by the kinetics and...

Hui Wang

Papers

Chemical fixation of carbon dioxide to cyclic carbonates under extremely mild conditions with highly active bifunctional catalysts

Insight into the mesoporous FexCe1−xO2−δ catalysts for selective catalytic reduction of NO with NH3: Regulable structure and activity

Selective catalytic oxidation of ammonia to nitrogen over CuO-CeO2 mixed oxides prepared by surfactant-templated method

Highly active electrophile–nucleophile catalyst system for the cycloaddition of CO2 to epoxides at ambient temperature

Superior Performance of Fe1-xWxOδ for the Selective Catalytic Reduction of NOx with NH3: Interaction between Fe and W