Preface.- Acknowledgements.- 1: Introduction.- 1.1. Catalysis. 1.2. Homogeneous catalysis. 1.3. Historical notes on homogeneous catalysis. 1.4. Characterization of the catalyst. 1.5. Ligand effects. 1.6. Ligands according to donor atoms. 2: Elementary Steps.- 2.1. Creation of a 'vacant' site and co-ordination of the substrate. 2.2. Insertion versus migration. 2.3. beta-Elimination and de-insertion. 2.4. Oxidative addition. 2.5. Reductive elimination. 2.6. alpha-Elimination reactions. 2.7. Cycloaddition reactions involving a metal. 2.8. Activation of a substrate toward nucleophilic attack. 2.9. sigma-Bond metathesis. 2.10. Dihydrogen activation. 2.11. Activation by Lewis acids. 2.12. Carbon-to-phosphorus bond breaking. 2.13. Carbon-to-sulfur bond breaking. 2.14. Radical reactions. 3: Kinetics.- 3.1. Introduction. 3.2. Two-step reaction scheme. 3.3. Simplifications of the rate equation and the rete-determining step. 3.4. Determining the selectivity. 3.5. Collection of rate data. 3.6. Irregularities in catalysis. 4: Hydrogenation.- 4.1. Wilkinson's catalyst. 4.2. Asymmetric hydrogenation. 4.3. Overview of chiral bidentate ligands. 4.4. Monodentate ligands. 4.5. Non-linear effects. 4.6. Hydrogen transfer. 5: Isomerisation.- 5.1. Hydrogen shifts. 5.2. Asymmetric isomerisation. 5.3. Oxygen shifts. 6: Carbonylation of Methanol and Methyl Acetate.- 6.1. Acetic acid. 6.2. Process scheme Monsanto process. 6.3. Acetic anhydride. 6.4. Other systems. 7: Cobalt Catalysed Hydroformylation.- 7.1. Introduction. 7.2. Thermodynamics. 7.3. Cobalt catalysed processes. 7.4. Cobalt catalysed processes for higher alkenes. 7.5. Kuhlmann cobalt hydroformylation process. 7.6. Phosphine modified cobalt catalysts: the shell process. 7.7. Cobalt carbonyl phosphine complexes. 8: Rhodium Catalysed Hydroformylation.- 8.1. Introduction. 8.2. Triphenylphosphine asthe ligand. 8.3. Diphosphines as ligands. 8.4. Phosphites as ligands. 8.5. Diphosphites. 8.6. Asymmetric hydroformylation. 9: Alkene Oligomerisation.- 9.1. Introduction. 9.2. Shell-higher-olefins-process. 9.3. Ethene trimerisation. 9.4. Other alkene oligomerisation reactions. 10: Propene Polymerisation.- 10.1. Introduction to polymer chemistry. 10.2. Mechanistic investigations. 10.3. Analysis by 13CNMR spectroscopy. 10.4. The development of metallocene catalysts. 10.5. Agostic interactions. 10.6. The effect of dihydrogen. 10.7. Further work using propene and other alkenes. 10.8. Non-metallocene ETM catalysts. 10.9. Late transition metal catalysts. 11: Hydrocyanation of Alkenes.- 11.1. The adiponitrile process. 11.2. Ligand effects. 12: Palladium Catalysed Carbonylations of Alkenes.- 12.1. Introduction. 12.2. Polyketone. 12.3. Ligand effects on chain length. 12.4. Ethene/propene/CO terpolymers. 12.5. Stereoselective styrene/CO terpolymers. 13: Palladium Catalysed Cross-Coupling Reactions.- 13.1. Introduction. 13.2. Allylic reaction. 13.3. Heck reaction. 13.4. Cross-coupling reaction. 13.5. Heteroatom-carbon bond formation. 13.6. Suzuki reaction. 14: Epoxidation.- 14.1. Ethene and propene oxide. 14.2. Asymmetric epoxidation. 14.3. Asymmetric hydroxilation of alkenes with osmium tetroxide. 14.4. Jacobsen asymmetric ring-opening of epoxides. 14.5. Epoxidations with dioxygen. 15: Oxydation with Dioxygen.- 15.1. Introduction. 15.2. The Wacker reaction. 15.3. Wacker type reactions. 15.4. Terephthalic acid. 15.5. PPO. 16: Alkene Metathesis.- 16.1. Introduction. 16.2. The mechanism. 16.3. Reaction overview. 16.4. Well-characterised tungsten and molybdenum catalysts. 16.5. Ruthenium catalysts. 16.6. Stereochemistry. 16.7. Catalyst decomposition. 16.8. Alkynes. 16.9. Industrial applications. 17: Enantioselective Cyclopropanation.-

Piet W. N. M. Van Leeuwen. Homogeneous catalysis—understanding the art. Kluwer, Dordrecht, 2004, 407 pp; (UK). ISBN 1‐4020‐1999‐8

Fossil fuels, which are recognized as unsustainable sources of energy, are continuously consumed and decreased with increasing fuel demands. Microalgae have great potential as renewable fuel sources because they possess rapid growth rate and the ability to store high-quality lipids and carbohydrates inside their cells for biofuel production. Microalgae can be cultivated on opened or closed systems and require nutrients and CO_2 that may be supplied from wastewater and fossil fuel combustion. In addition, CO_2 capture via photosynthesis to directly fix carbon into microalgae has also attracted the attention of researchers. The conversion of CO_2 into chemical and fuel (energy) products without pollution via this approach is a promising way to not only reduce CO_2 emissions but also generate more economic value. The harvested microalgal biomass can be converted into biofuel products, such as biohydrogen, biodiesel, biomethanol, bioethanol, biobutanol and biohydrocarbons. Thus, microalgal cultivation can contribute to CO_2 fixation and can be a source of biofuels. This article reviews the literature on microalgae that were cultivated using captured CO_2, technologies related to the production of biofuels from microalgae and the possible commercialization of microalgae-based biofuels to demonstrate the potential of microalgae. In this respect, a number of relevant topics are addressed: the nature of microalgae (e.g., species and composition); CO_2 capture via microalgae; the techniques for microalgal cultivation, harvesting and pretreatment; and the techniques for lipid extraction and biofuel production. The strategies for biofuel commercialization are proposed as well.

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A Review: Microalgae and Their Applications in CO_2 Capture and Renewable Energy

Hydrogenation of nitrile butadiene rubber (NBR) is an important research topic in the field of chemical modification of unsaturated polymers. This review provides an overview of the fundamental data, challenges, and recent advances in the research area of homogeneous hydrogenation of NBR. Besides NBR and its hydrogenation product HNBR, some other important elastomers such as styrene butadiene rubber (SBR), polybutadiene rubber (BR), polystyrene-b-polybutadiene-b-polystyrene (SBS block copolymer), and natural rubber (NR) were also involved for the related hydrogenation reactions and characterization. A brief comparison of hydrogenation catalysts including the heterogeneous and homogeneous catalysts was first conducted and the importance of rhodium (Rh) complex catalysts for homogeneous hydrogenation of elastomers was addressed. This article continued to discuss the reaction pathways for realization of the homogeneous hydrogenation of NBR. This was followed by an examination of the microstructures and chara...

Homogeneous Hydrogenation Art of Nitrile Butadiene Rubber: A Review

Virus-like particles (VLPs) are unique macromolecular structures that hold great promise in biomedical and biomaterial applications. The interior of the 30 nm-diameter Qβ VLP was functionalized by a three-step process: (1) hydrolytic removal of endogenously packaged RNA, (2) covalent attachment of initiator molecules to unnatural amino acid residues located on the interior capsid surface, and (3) atom-transfer radical polymerization of tertiary amine-bearing methacrylate monomers. The resulting polymer-containing particles were moderately expanded in size; however, biotin-derivatized polymer strands were only very weakly accessible to avidin, suggesting that most of the polymer was confined within the protein shell. The polymer-containing particles were also found to exhibit physical and chemical properties characteristic of positively charged nanostructures, including the ability to easily enter mammalian cells and deliver functional small interfering RNA.

Encapsidated Atom-Transfer Radical Polymerization in Qβ Virus-like Nanoparticles

Virus-like particles (VLPs) are unique macromolecular structures that hold great promise in biomedical and biomaterial applications. The interior of the 30 nm-diameter Qβ VLP wasfunctionalized by a three-step process: (1)hydrolytic removal of endogenously packaged RNA, (2) covalent attachment of initiator molecules to unnatural amino acid residues located on the interior capsid surface, and (3) atom-transfer radical polymerization of tertiary amine-bearing methacrylatemonomers.Theresultingpolymer-containingparticlesweremoderatelyexpandedin

Encapsidated Atom-Transfer Radical Polymerization in Qβ Virus-like

Development of a green separation technique for recovery of Wilkinson's catalysts from bulk hydrogenated nitrile butadiene rubber

The central challenge that has limited the development of catalytic hydrogenation of diene-based polymer latex (i.e., latex hydrogenation) in large-scale production pertains to how to accomplish the optimal interplay of accelerating the hydrogenation rate, decreasing the required quantity of catalyst, and eliminating the need for an organic solvent. Here, we attempt to overcome this dilemma through decreasing the dimensions of the polymer substrate (such as below 20 nm) used in the hydrogenation process. Very small diene-based polymer nanoparticles were synthesized and then used as the substrates for the subsequent latex hydrogenation. The effects of particle size, temperature, and catalyst concentration on the hydrogenation rate were fully investigated. An apparent first-order kinetic model was proposed to describe the rate of hydrogen uptake with respect to the concentration of the olefinic substrate (CC). Mass transfer of both the hydrogen and catalyst involved in this solid (polymer)–liquid (water)–gas (hydrogen) three-phase latex system is discussed. The competitive coordination of the catalyst between the CC and acrylonitrile units within the copolymer was elucidated. It was found that (1) using very small diene-based polymer nanoparticles as the substrate, the hydrogenation rate of polymer latex can be increased vastly to achieve a high conversion of 95% while a quite low level of catalyst loading is required; (2) this latex hydrogenation process was completely free of organic solvent and no cross-linking was found; (3) the mass transfer of hydrogen is not a rate-determining step in the present hydrogenation reactions; (4) the catalyst was dispersed homogeneously within the polymer nanoparticles; (5) for the reaction that has reached about 95 mol % conversion, the kinetic study shows that the reaction is chemically controlled with an apparent activation energy of 100–110 kJ/mol; (6) the strong coordination of C[tbond]N to the catalytically active species RhH2Cl(PPh3)2 imposed a negative effect on the hydrogenation activity. The present research provides a comprehensive study to appreciate the underlying chemistry of latex hydrogenation of diene-based polymer nanoparticles and more importantly shows great promise toward the commercialization of a “green” catalytic hydrogenation operation of a diene-based polymer latex in industry. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

Organic solvent-free catalytic hydrogenation of diene-based polymer nanoparticles in latex form. Part II. Kinetic analysis and mechanistic study

Carbon dioxide-expanded methanol (CXM) is for the first time employed to recover Wilkinson's catalyst from the matrix of hydrogenated nitrile butadiene rubber (HNBR) using the chelating agent N,N,N′,N′,N″-pentamethyldiethylenetriamine (PMDETA). The effects of temperature and pressure on the extraction performance were carefully investigated over the temperature range of 40–100 °C and the pressure range of 20–20 MPa. Increasing temperature effectively increased the extraction rate and became less influential when temperature is above 80 °C. Increasing pressure over the different pressure ranges at 80 °C impacted the extraction rate differently. 6 MPa was considered as the optimal pressure at 80 °C. The rhodium residue was reduced from 700 to 222 ppm by a 5 h extraction at 6 MPa and 80 °C. An extraction mechanism was illustrated for interpreting the present extraction system and guiding the future work. This study establishes a technology platform for separating the expensive catalyst from the polymer matrix, using “green” CO 2 -expanded liquids.

Recovery of Wilkinson's catalyst from polymer based matrix using carbon dioxide expanded methanol

Antineoplastic drug ellipticine and its derivatives are used in human cancer therapy. However, their clinical applications have been limited by its great hydrophobicity and severe side effects. An efficient delivery system is therefore very desirable. In this research, an ellipticine-loaded core-shell structured nanosphere namely poly(DEAEMA)-poly(PEGMA) is designed as a drug carrier and prepared via a two-step semibatch emulsion polymerization method where DEAEMA and PEGMA represent 2-(diethylamino)ethyl methacrylate and poly(ethylene glycol) methacrylate, respectively. The in-vitro release profiles of ellipticine towards the different pH liposome vesicles are recorded as a function of time at 37 °C. It is found that release of ellipticine from the core-shell polymer matrix is a pH-responsive and controlled release process. The three pH's of 3, 4, and 5 trigger a significant ellipticine release of 88% after 98 h, 83% after 98 h, and 79% after 122 h, respectively. The release mechanism of ellipticine from the core-shell polymer matrix under acidic conditions is explored. The synthesis and encapsulation process developed herein provides a new perspective for the development of appropriate delivery systems to deliver the ellipticine and its analogues, as well as other types of hydrophobic drugs to a given target cell or tumor tissue.

Lijuan Yang

Papers

Homogeneous Hydrogenation Art of Nitrile Butadiene Rubber: A Review

Development of a green separation technique for recovery of Wilkinson's catalysts from bulk hydrogenated nitrile butadiene rubber

Organic solvent-free catalytic hydrogenation of diene-based polymer nanoparticles in latex form. Part II. Kinetic analysis and mechanistic study

Recovery of Wilkinson's catalyst from polymer based matrix using carbon dioxide expanded methanol

Preparation of pH-responsive polymer core-shell nanospheres for delivery of hydrophobic antineoplastic drug ellipticine.