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Abstract: Density functional theory (DFT) calculation was used to investigate the mechanism of [Au.sub.3] clusters, separately supported on pure graphene ([Au.sub.3]/graphene) and one graphitic N-doped graphene ([Au.sub.3]/N-graphene). These supported [Au.sub.3] [...]

Olefin metathesis catalysts provide access to molecules that are indispensable to physicians and researchers in the life sciences (1,2).A persisting problem, however, is the dearth of chemical transformations that directly generate acyclic Zallylic alcohols, including products that contain a hindered neighbouring substituent or reactive functional units such as a phenol, an aldehyde, or a carboxylic acid. Here we present an electronically modified ruthenium--disulfide catalyst that is effective in generating such high-value compounds by cross-metathesis. The ruthenium complex is prepared from a commercially available precursor and an easily generated air-stable zinc catechothiolate. Transformations typically proceed with 5.0 mole per cent of the complex and an inexpensive reaction partner in 4-8 hours under ambient conditions; products are obtained in up to 80 per cent yield and 98:2 Z:E diastereoselectivity. The use of this catalyst is demonstrated in the synthesis of the naturally occurring anti-tumour agent neopeltolide and in a single-step stereoselective gram-scale conversion of a renewable feedstock (oleic acid) to an anti-fungal agent. In this conversion, the new catalyst promotes cross-metathesis more efficiently than the commonly used dichlororuthenium complexes, indicating that its utility may extend beyond Z-selective processes., In 2009, it was demonstrated that a molybdenum (Mo) monopyrrolide aryloxide complex can promote ring-opening/cross-metathesis with high Z selectivity (3). This initial discovery and the attendant stereochemical model paved the [...]

A tutorial is provided for methods to accurately and reproducibly determine the activity of Pt-based electrocatalysts for the oxygen reduction reaction in proton exchange membrane fuel cells and other applications. The impact of various experimental parameters on electrocatalyst activity is demonstrated, and explicit experimental procedures and measurement protocols are given for comparison of electrocatalyst activity to fuel cell standards. (To listen to a podcast about this article, please go to the Analytical Chemistry multimedia page at pubs.acs.org/page/ancham/audio/index.html.) 10.1021/ac100306c

Continuous, on-site monitoring of personal exposure levels to occupational chemical hazards in ambient air is a longstanding analytical challenge. Such monitoring is required to institute appropriate health measures but is often limited by the time delays associated with batch air sampling and the need for off-site instrumental analyses. In this work, we report on the first attempt to use the catalytic properties of perfluorosulfonic acid (PSA) membranes to obtain a rapid, selective, and highly sensitive optical response to trimellitic anhydride (TMA) in the gas phase for portable sensor device application. TMA is used as starting material for various organic products and is recognized to be an extremely toxic agent by the National Institute for Occupational Safety and Health (NIOSH). Resercinol dye is shown to become immobilized in PSA membranes and diffusionally constrain an orange brown product that results from acid-catalyzed reaction with more rapidly diffusing TMA molecules. FTIR, UV/ vis, reaction selectivity to TMA versus trimellitic acid (TMLA), and homogeneous synthesis are used to infer 5,7- dihydroxyanthraquinone-2-carboxylic acid as the acylation product of the reaction. The color response has a sensitivity to at least 3 parts per billion (ppb) TMA exposure and, in addition to TMLA, excludes maleic anhydride (MA) and phthalic anhydride (PA). Solvent extraction at long limes is used to determine that the resorcinol extinction coefficient in 1100 EW PSA membrane has a value of 1210 [m.sup.2]/g at 271.01 nm versus a value of 2010 [m.sup.2]/g at 275.22 nm in 50 vol% ethanol/water solution. The hypsochromic wavelength shift and reduced extinction coefficient suggest that the polar perfluorosulfonic acid groups in the membrane provide the thermodynamic driving force for diffusion and immobilization. At a resorcinol concentration of 0.376 g/L in the membrane, a partition coefficient of nearly unity is obtained between the membrane and solution concentrations and a maximum conversion rote of one ambient TMA molecule for every two membrane-immobilized resorcinol molecules is observed in 15 min. 10.1021/ac101356j

The hemin/G-quadruplex horseradish peroxidase-mimicking DNAzyme is assembled on Au electrodes. It reveals bioelectrocatalytic properties and electrocatalyzes the reduction of [H.sub.2][O.sub.2]. The bioelectrocatalytic functions of the hemin/G-quadruplex DNAzyme are used to develop electrochemical sensors that follow the activity of glucose oxidase and biosensors for the detection of DNA or low-molecular-weight substrates (adenosine monophosphate, AMP). Hairpin nucleic structures that include the G-quadruplex sequence in a caged configuration and the nucleic acid sequence complementary to the analyte DNA, or the aptamer sequence for AMP, are immobilized on Au-electrode surfaces. In the presence of the DNA analyte, or AMP, the hairpin structures are opened, and the hemin/G-quadruplex horseradish peroxidase-mimicking DNAzyme structures are generated on the electrode surfaces. The bioelectrocatalytic cathodic currents generated by the functionalized electrodes, upon the electrochemical reduction of [H.sub.2][O.sub.2], provide a quantitative measure for the detection of the target analytes. The DNA target was analyzed with a detection limit of 1 x [10.sup.-12] M, while the detection limit for analyzing AMP was 1 x [10.sup.-6] M. Methods to regenerate the sensing surfaces are presented. 10.1021/ac100095u

A procedure based on microwave-induced combustion (MIC) was applied for carbon nanotabe (CNT) digestion and further determination of La and Ni by inductively coupled plasma optical emission spectrometry (ICP OES). Samples (up to 400 mg) were completely combusted at 20 bar of oxygen, and a reflux step was applied to improve the analyte absorption. Combustion was finished in less than 50 s, and analytes were absorbed in diluted acid solution. Absorbing solutions ranging from 1 to 12 mol [L.sup.-1] for HCl and from 1 to 14 mol [L.sup.-1] HN[O.sub.3] were tested. Accuracy for both analytes was evaluated using certified reference materials and analyte spikes. Neutron activation analysis was also used to check accuracy for La. Agreement was better than 96% for La and Ni using a 4 mol [L.sup.-1] absorbing solution of HN[O.sub.3] or HCl and 15 min of reflux. The residual carbon content was lower than 0.5%. Up to eight samples could be digested simultaneously in 36 min, that makes the throughput using MIC more suitable when it is compared to the digestion by dry ashing as recommended by other procedures. The obtained limits of detection using MIC were lower than those using dry ashing, and a single absorbing solution, e.g., diluted HN[O.sub.3], can be used for simultaneous determination of La and Ni by 1CP OES. 10.1021/ac100429v

Dye mixing effects on water splitting activity of KTa[O.sub.3] photocatalyst modified by various porphyrinoids was investigated. Photocatalytic activity of dye-modified KTa[O.sub.3] catalyst is greatly improved by mixing various porphyrinoids, in which transition metals such as Cr, Fe, and Co are used as central metal. Pentametylene bis[4-(10, 15, 20-triphenyl porphine-5-yl) benzoate]-dizinc(II) (Zn-TPP dimer) showed positive effect on photocatalytic activity, and [H.sub.2] and [O.sub.2] formation rates are 365 [micro]mol [g.sup.-1.sub.-cat], [h.sup.-1] and 152 [micro]mol [g.sup.-1.sub.-cat], [h.sup.-1], respectively. On the other hand, the combination of chloroprotoporphyrinato iron (III) (chlorohemin) with Cr-phthalocyanine (CrPc) is the most effective for increasing water splitting activity, and the formation rates of [H.sub.2] and [O.sub.2] are 2.12 mmol [g.sup.-1.sub.-cat], [h.sup.-1] and 1.11 mmol [g.sup.-1.sub.-cat], [h.sup.-1] respectively. Energy conversion efficiency of this photocatalyst is estimated to be approximately 0.05%. From X-ray photoelectron spectroscopy measurement and cyclic voltammetry of organic dyes, it is suggested that the electronic state of the dye mixture is modified compared with that of a single dye. Energy transfer between mixing dyes is observed in the fluorescence spectra of dye-modified KTa[O.sub.3] photocamlysts. Recombination of photoexited charge in KTa[O.sub.3] is clearly suppressed by dye mixing, thus improvement of photocatalytic activity is attributed to the lengthening of excitation lifetime. This study reveals that mixing porphyrinoid dyes is an effective method for increasing water splitting activity of dye-modified KTa[O.sub.3] photocatalysts. [DOI: 10.1115/1.4001179] Keywords: photocatalyst, water splitting, porphyrin, dye mixing, charge transfer

BiV[O.sub.4] powder was easily prepared from [Bi.sub.2][O.sub.3] and [V.sub.2][O.sub.5] in an aqueous nitric acid solution at room temperature. The obtained crystal structure depended on the molar ratio of [Bi.sub.2][O.sub.3] to [V.sub.2][0.sub.5], which is the concentration and volume of an aqueous nitric acid solution. BiV[O.sub.4] with monoclinic scheelite structure formed using starting materials, in which the molar ratio of [Bi.sub.2][O.sub.3] to [V.sub.2][0.sub.5] was 1:1. When the molar ratio was 4:3, BiV[O.sub.4] with tetragonal zircon structure was obtained. Although BiV[O.sub.4] with monoclinic scheelite structure was platelike particles reflecting the crystal structure, the thickness of the particle increased with an increase in the concentration of an aqueous nitric acid solution. The obtained BiV[O.sub.4] with monoclinic scheelite structure showed good photocatalytic performances for [O.sub.2] evolution and methylene blue degradation under visible-light irradiation. [DOI: 10.1115/1.4001172]

Pt-Ag nanoparticles were prepared on a glassy carbon (GC) surface by pulsed electrodeposition and tested using cyclic voitammetry and scanning electrochemical microscopy (SECM) with respect to their possible use as catalyst material for oxygen reduction in 400 mM HCl solution. For comparison, a Pt catalyst was investigated under similar conditions. The redox competition mode of scanning electrochemical microscopy (RC-SECM) was adapted to the specific conditions caused by the presence of CI ions and used to visualize the local catalytic activity of the Pt-Ag deposits. Similarly prepared Pt deposits were shown to dissolve underneath the SECM tip. Pt-Ag composites showed improved long-term stability toward oxygen reduction as compared with Pt even under multiple switching off to open-circuit potential in 400 mM HCl. 10.1021/ac902620g

Silica-bonded S-sulfonic acid (SBSSA) was prepared by the reaction of 3-mercaptopropy 1 silica (MPS) and chlorosnironic acid in teri-bulylmethyl ether, and used as a catalyst for line silylation of hydroxyl groups. A good range of primary, secondary alcohols and phenolic hydroxyl groups were effectively converted into their corresponding trimethylsilyl ethers with hexamethyldisilazane (HMDS) in the presence of catalytic amounts of SBSSA under mild conditions at room temperature with short reaction times and in good-to-excellent yields. An excellent chemoselective silylation of hydroxyl groups in the presence of other functional groups was also observed. The heterogeneous catalyst was recycled for 30 runs upon the reaction of benzyl alcohol with HMDS without lossing its catalytic activity. Key words: silylation, silica-bonded S-sulfonic acid, hydroxyl groups, alcohols, catalyst. On a prepare de l'acide S-sulfonique lie a de la silice par (ASSLS) par reaction du 3-mercaptopropylsilicium (MPS) et de l'acide chlorosulfonique dans le ether de tert-butylmethyle et on l'a utilise comme catalyseur pour la silylation de groupes hydroxyles. On a ainsi pu transformer un ensemble representatif de groupes hydroxyles d'alcools primaires et secondares et phenoliques en ethers trimethylsilyles correspondants par reaction avec de l'hexamethyldisilazane (HMDS) en presence de quantites catalytiques d'acide S-sulfonique lie a de la silice, dans des conditions douces, a la temperature ambiante, avec des courts temps de reaction et avec des rendements allant de bons a excellents. On a pu aussi observer une excellent silylation chimioselective de groupes hydroxyles en presence d'autres groupes fonctionnels. Le catalyseur heterogene a pu etre recycle au moins trente fois, sans perte d'activite, pour la reaction de l'alcool benzylique avec le HMDS. Mots-cles: silylation, acide S-sulfonique lie a de la silice, groupes hydroxyles, catalyseur. [Traduit par la Redaction] doi: 10.1139/V09-162, Introduction In recent years, there has been much attention on the search for environmentally benign chemical processes or methodologies, because they are essential for the conservation of the global ecosystem. [...]

A new type of photocatalyst is described that has used the enhanced electric field amplitude on the surface of Ag nanoparticles (NPs) in the spectral vicinity of their plasmon resonances, particularly for the near-ultraviolet region. The enhancement of the photocatalytic activity has increased with a decreased thickness of the Si[O.sub.2] cell.

The application and scope of chalcogenides as organocatalysts in ylide-mediated synthesis of enantioselective aziridines is reviewed. The chalcogenides can also used in asymmetric synthesis of carbonyl compounds such as indole alkaloids.

The application and scope of a new class of chiral Bronsted-acid organocatalysts used in number of enantioselective carbon-carbon bond-forming reactions is reviewed.

The design and developmental progress observed in nucleophile catalysts, 4-(dimethylamino)pyridine (DMAP) derivatives, utilized in enantioselective synthesis are reviewed.

The scope of the four-step mechanism for [d.sup.0] complexes and the factors that favor the olefin metathesis reaction are evaluated by studying the influence of the metal (Mo, W and Re), the imido vs. the alkylidyne and the X and Y spectator ligands. The results have shown that the Re complexes are less efficient than the Mo and W catalysts, except when Re is unsymmetrically substituted.

Experiments were conducted to demonstrate the creation and observation of para-hydrogen-induced polarization in heterogeneous hydrogenation reactions. The results suggest that mechanism of heterogeneous hydrogenation reactions involving immobilized metal complexes could be potentially developed into a practical tool for producing catalyst-free fluids with highly polarized nuclear spins for a broad range of hyperpolarized NMR and MRI applications.

Properties of dirhodium catalysts with cyclometalated aryl phosphine ligands were studied by examining the acid-base reaction of [Rh.sub.2][(RC[O.sub.2]).sub.4-n][(PC).sub.2][([H.sub.2]O).sub.2] catalysts with different Lewis bases. The dinuclear rhodium compound showed considerable higher ratio of equilibrium constants and computational interaction energies.

Two anaerobes originally isolated for their abilities to respire selenium oxyanions are shown to achieve growth by reduction of either tellurite [Te(IV)] or tellurate [(Te(VI)] to tellurium [Te(0)]. The use of microorganisms for generating Te nanomaterials is an alternative method for bench-scale process.

A new approach is described for the synthesis of macrocyclic tetralactones with different ring sizes having a wide variety of spacers. This method has also used Grubbs' catalyst for the synthesis of macrocyclic tetralactones having different ring sizes and spaces, which are important to the biologically significant materials and supramolecular chemistry.

The reaction methodology for intermolecular C-H amination of benzylic and 3 degree C-H bonds using the starting alkane as the limiting reagent is presented. Results reveal that C-H amination follows through a concerted asynchronous two-electron oxidation pathway.

As part of an ongoing effort to develop a microscale gas turbine engine for power generation and micropropulsion applications, this paper presents the design, modeling, and experimental assessment of a catalytic combustion system. Previous work has indicated that homogenous gas-phase microcombustors are severely limited by chemical reaction timescales. Storable hydrocarbon fuels, such as propane, have been shown to blow out well below the desired mass flow rate per unit volume. Heterogeneous catalytic combustion has been identified as a possible improvement. Surface catalysis can increase hydrocarbon-air reaction rates, improve ignition characteristics, and broaden stability limits. Several radial inflow combustors were micromachined from silicon wafers using deep reactive ion etching and aligned fusion wafer bonding. The 191 m[m.sup.3] combustion chambers were filled with platinum-coated foam materials of various porosity and surface area. For near stoichiometric propane-air mixtures, exit gas temperatures of 1100 K were achieved at mass flow rates in excess of 0.35 g/s. This corresponds to a power density of ~1200 MW/[m.sup.3]; an 8.5-fold increase over the maximum power density achieved for gas-phase propane-air combustion in a similar geometry. Low-order models, including time-scale analyses and a one-dimensional steady-state plug-flow reactor model were developed to elucidate the underlying physics and to identify important design parameters. High power density catalytic microcombustors were found to be limited by the diffusion of fuel species to the active surface, while substrate porosity and surface area-to-volume ratio were the dominant design variables. [DOI: 10.1115/1.2204980]

Various steps of preparation process of Pt/[gamma]- [AI.sub.2][O.sub.3] using hydroxyl-terminated generation four (G4OH) PAMAM dendrimers as the templating agents are monitored by extended X-ray adsorption fine structure (EXAFS) spectroscopy. The results indicate that the hydrolysis of two different platinum precursors, namely [H.sub.2]Pt[CI.sub.6] and [K.sub.2]Pt[CI.sub.4] leads to the formation of [Pt[Cl.sub.3][[H.sub.2]O.sub.3]].sup.+ and [Pt[Cl.sub.2][[H.sub.2]O.sub.2]] species respectively.

Study is conducted to show that by using a simple MAS scheme for the constant-time (CT) acquisition of proton signal, a significant improvement in resolution can be observed in the NMR spectra of surface organometallic catalyst precursors. It is found that in the complex [syn-(SiO)Mo(=NAr)(=CH[super t]Bu)-(CH2[super t]Bu)], this approach allowed for the unambiquous observation and assignment of the methylene protons.

A simple means of calculating the standard potential for reduction of the acid whose p[K.sub.a] is known in the solvent being used is demonstrated to facilitate the comparison of catalytic efficiencies. The results show that direct reduction could be almost completely suppressed by using mercury or amalgamated gold electrode, even at very negative potentials.

This theoretical study was inspired by the perpetual debate over the so-called 'dormancy' of the active sites in propylene polymerization, i.e., a drop in their activity after a regioerror (2,1-insertion), which was reported to occur in many (although not all) catalytic systems. To explore the range of possible situations, we have selected two homogeneous systems of fundamentally different structure: an octahedral system of [C.sub.2] symmetry with a tetradentate--N--N--O--ligand and a bridged indenyl catalyst. This choice was not accidental; it is in these two systems where the experimentalists cannot reach a consensus about dormancy. Our density-functional theory calculations explain why in certain catalytic systems both primary and secondary alkyl complexes can be equally reactive toward propylene polymerization, despite the intuitive concept of dormancy. To understand such a behavior, it was imperative to build an extensive model, including the counteranion and solvent effects. The discussion is also supplemented by our latest calculations on the classical second-generation Ziegler--Natta system. catalyst | density-functional theory | olefin polymerization | propylene | transition metals

After five decades of largely serendipitous (albeit formidable) progress, catalyst design in Ziegler--Natta olefin polymerization, i.e., the rational implementation of new active species to target predetermined polyolefin architectures, has ultimately become a realistic ambition, thanks to a much deeper fundamental understanding and major advances in the tools of computational chemistry. In this article, we discuss, as a case history, a unique class of stereorigid [C.sub.2]-symmetric bis(phenoxy-amine)Zr(IV) catalysts with controlled kinetic behavior. A large variety of polypropylene microstructures have been obtained with these catalysts by modulating the steric demand of one key substituent, without altering the nature and symmetry of the ancillary ligand framework, under the guidance of computer modeling. This unusual achievement is relevant per se and for the perspective implications in catalyst discovery. enantioselectivity | olefin polymerization | polypropylene

A series of bimetallic organo-group 4 'constrained geometry' catalysts and binuclear bisborane and bisborate cocatalysts have been synthesized to probe catalyst center--catalyst center cooperativity effects on olefin enchainment in homogenous olefin polymerization and copolymerization processes. Significant nuclearity effects are found versus mononuclear controls, and the effect can be correlated with metal-metal approach distances and ion pairing effects. Novel polymer structures can be obtained by using such binuclear catalyst/cocatalyst systems. catalysis | polymer | polyolefin

This article reviews the surface science of the heterogeneous olefin polymerization catalysts. The specific focus is on how to prepare and characterize stereochemically specific heterogeneous model catalysts for the Ziegler--Natta polymerization. Under clean, ultrahigh vacuum conditions, low-energy electron irradiation during the chemical vapor deposition of model Ziegler--Natta catalysts can be used to create a 'single-site' catalyst film with a surface structure that produces only isotactic polypropylene. The polymerization activities of the ultra-high vacuum-prepared model heterogeneous catalysts compare well with those of conventional Ziegler--Natta catalysts. X-ray photoelectron spectroscopic analyses identify the oxidation states of the Ti ions at the active sites. Temperature-programmed desorption distinguishes the binding strength of a probe molecule to the active sites that produce polypropylenes having different tacticities. These findings demonstrate that a surface science approach to the preparation and characterization of model heterogeneous catalysts can improve the catalyst design and provide fundamental understanding of the single-site olefin polymerization process. Ziegler--Natta

Density functional theory (DFT) is used to study the CO adsorption on the Fe3O4(111) surfaces, which are considered as active catalysts in water-gas shift reaction. The results have shown that the adsorbed CO can migrate from the on-top site to the bridge site or 3-fold site and the oxidation of CO through surface oxygen atoms is feasible.

Iron substituted cubic cage type mesoporous molecular sieves FeSBA-I were synthesized in a highly acidic media using cetyltriehtylammonium bromide as a template. Most of the iron atoms in FeSBA-I were found to be in # coordination state and the FeSBA-I catalyst showed superior catalytic performance for the tert-butylation of phenol as compared to the uni-dimensional mesoporous catalysts.

Biosynthesis of allophycocyanin (APC) (alpha)-subunit was carried out to identify the lyase that catalyzes the chromophorylation of the APC (alpha)-subunit (ApcA). It was seen that apo-ApcA can become covalently modified by PCB to form a fluorescent chromoprotein and no known chromophore lyase was necessary to mediate the modification reaction. Results also indicate that ApcA has autocatalytic bilin:biliprotein lyase activity.

A novel, efficient method is described to synthesize highly active Au catalysts supported on mesoporous silica (SBA-15) through a gold cationic complex precursor via a wet chemical process. The gold nanoparticles in mesoporous silica are generated by reduction under [H.sub.2] atmosphere and the resulting Au catalyst has displayed an extremely high catalytic activity for CO oxidation even below 273 K.

A series of 6- and 8-substituted chromenes are investigated for asymmetric epoxidation using chiral ketone catalysts. The enhanced enantioselectivity is likely due to the beneficial interaction between the 6-substituent of the substrate and the N-aryl or aryl group of the ketone catalyst.

The new experimental data and mechanistic studies of the bromate-hypophosphite-acetone-Mn(II)-Ru(bby)(sub 3)(super 2+) batch oscillator are presented. The results have shown that the two oscillatory sequences seen in the full system have originated from two oscillatory subsystems, the Mn(II)-catalyzed bromate-hypophosphite-acetone and the Ru(bby)(sub 3)(super 2+)-catalyzed bromate-bromoacetone reactions.

The synthesis and characterization of a series of mixed W-Zr polynuclear Lindqvist-type complexes, deriving from hexatungstate [W6O19](super 2-), are reported. This spectroscopic characterization has provided useful standards for the study of heterogeneous tungstated zirconia catalysts, which is important for the skeletal isomerization of light n-alkanes.

Various studies are conducted to show the influence of pressure and temperature on an asymmetric, regio- and stereoselective alternating copolymerization of CO(sub 2) and racemic aliphatic epoxides. The studies of the polymer selectivity with the enantioselectivity and stereochemistry control shows that the copolymerization involves the coordination activation of the monomer by the electrophile and polymer chain growth predominantly occurring in the nucleophile.

A study was conducted on the interfaces between the catalyst droplet and the nanostructure grow in well-defined mutual crystallographic relationships using Au guided growth of ZnO. The results revealed that the nanostructure defines the crystallographic orientation of the solidifying Au droplet.

Impregnation is used for the calcination of a Fe/MgO catalyst to result in a solid solution with the growth of single- and double-walled carbon nanotubes. The formation of iron layers on the catalyst surface is caused due to the hydrogen reduction resulting in a high yield of impurity-free nanotubes.

The visible (532 and 442 nm) and UV (325nm) Raman spectra of metal molybdates and metal vanadates were compared to examine the variation in the excitation energy. It was revealed that the relative quality of the resulting Raman spectra strongly depends on the absorption properties of the bulk mixed oxide samples that possess low absorption.

A study is conducted on the recognition of uridine by the series of Zn(II) macrocyclic complexes and the design for the design of RNA cleavage catalysts. It is suggested that it may be possible to exploits Zn(II) macro cyclic complex interaction with uridine groups to increase the interaction of a tethered metal ion catalyst with RNA and to orient the catalyst with respect to the phosphate diester.

The alkylation of m-cresol with isopropyl alcohol in the presence of novel superacidic catalysts named as UDCaT-4, UDCaT-5, and UDCaT-6 is investigated. UDCaT-5 is found to be the best catalyst in terms of activity and selectivity.

Catalytic asymmetric synthesis of the natural antibodies fostriecin (CI-920) and its analogue 8-epi-fostriecin and evaluation of their biological activity are described. In one assay, 8-epi-fostriecin might be useful as unique biological tools, which are more selective and more potent PP2A inhibitor than natural fostriecin.

A practical synthesis of Shi's diester for catalytic asymmetric epoxidations that is developed is described. The work up procedures is made easy to the minimum leading to a very excellent practical preparation method.

Periodic density functional calculations were used to investigate the structure and stability of epitaxial vanadium oxide films grown on the TiO2(001) anatase surface. The electron structure of the films was studied and the results revealed that the terminal oxygens carried by the surface dioxovanadium species had strong nucleophilic character, which makes them potential active centers for selective oxidation catalysts.

The oxide-based supported catalysts with high specific area were produced in one step through combination of the impregnation and solution combustion synthesis approaches. The study formulated the fundamental basis on the so-called combustion-impregnation approach for synthesis of high-surface area supported catalysts.