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Well-defined recyclable Pd- and Rh-bipyridyl group-impregnated SBA-15 catalysts were prepared for C-C bond coupling reaction and selective hydrogenation reactions, respectively. These SBA-15 derived ligands for the catalysts were prepared by direct and indirect co-condensation method using bipyridyl-linked methallylsilane. This indirect method, involving methoxysilane generated from methallylsilane shows higher loading efficiency of transition metal catalysts on SBA-15 than the direct use of methallylsilane.

Nanoscale dynamic processes such as the diffusion of ions within solid-state structures are critical for understanding and tuning material properties in a wide range of areas, such as energy storage and conversion, catalysis, and optoelectronics. In the generation of new types of nanocrystals (NCs), diffusion-mediated ion exchange reactions have also been proposed as one of the most effective transformational strategies. However, retaining the original morphology and crystal structure of metal oxide NCs has been challenging because of Kirkendall void formation, and there has been no success, especially for anion exchange. Here we show that with the aid of an oxygen extracting reagent (OER), anion diffusion is dramatically accelerated and morphology-conserving anion exchange without Kirkendall void formation is possible. In the case of the conversion of Fe

Despite the many advances that have been made in using anionic surfactants to disperse and sort single-walled carbon nanotubes (SWNTs) for optoelectronic applications, one-pot methods for deposition of SWNTs in a diameter (dt) and position controlled manner from as-dispersed sample are essential. Here, we designed and prepared flavin-containing self-assembled monolayers (flavin-SAMs) that can be used to assemble dt-selective individualized SWNT networks directly from SWNT dispersions by using the widely-used anionic surfactant. For a given glass substrate, the dimethallylsilane-linked azide, along with surface immobilization was employed to have Click reaction with terminal acetylene tethered to flavin group known to have strong affinity with SWNT. As demonstrated by atomic force microscopy and other methods, along successful assembly of individualized networks, the SWNTs are either fully or partially wrapped in a dt selective manner by isoalloxazine moieties tethered to the surface, displaying Langmuir isotherm adsorption behaviors in a dipping method dependent manner. The assembled SWNT network secures photoluminescence and electrical conductivity albeit its intimacy to underlying substrate and near monolayer coverage of SWNT network, respectively, and, furthermore, preferentially takes place on flavin-SAM over hydrophobic surface.

A new method for covalent immobilization of catalytic hydroesterification modified polybutadiene on a silica surface is described. Compared to conventional immobilization procedures, the new protocol enables control of the functional group composition on the modified silica surface.

We have previously shown that an activated carbon-supported ruthenium catalyst promoted with ReO x (RuRe/AC) is highly active for the hydrodeoxygenation (HDO) of lignin-derived phenols (e.g., guaiacol). In this work, we have investigated the effect of carbon supports on the structure and HDO activity of bimetallic RuRe particles using three different carbon supports, i.e., activated carbon (AC), carbon black (Vulcan carbon, VC), multi-walled carbon nanotube (MWCNT). The MWCNT- and VC-supported catalysts show remarkably enhanced activity and hydrocarbon selectivity for the HDO of a range of phenolic molecules (i.e., guaiacol, eugenol, benzyl phenyl ether) compared to RuRe/AC. STEM-EDS and XPS analyses reveal that bimetallic RuRe particles are more common than monometallic Ru or Re particles in the VC- and MWCNT-supported catalysts, and hexavalent rhenium species are more easily reduced to tetravalent rhenium during the HDO reactions in these catalysts, suggesting that Ru and Re in close proximity are required for the efficient hydrogenolysis of phenols. The formation of bimetallic particles on the AC surface is likely hindered by high microporosity and high surface oxygen functionalities, both of which restrict the mobility of Re and Ru for assembly.

Styrylsilanes serve as new coupling reagents for introducing organic functional groups on silica and glass surfaces. Functionalized styrylsilanes, which are readily prepared via catalytic hydrosilylation of the corresponding phenylacetylenes with silanes, are immobilized on silica through acid catalyzed processes under mild conditions.

A simple, one-step method for covalent bond immobilization of biomolecules on silica operated in water is described. In the approach, an NHS-ester linked methallylsilane is utilized as a bifunctional linker to couple the biomolecule to the silica surface. Weak organic acid such as acetic acid activates the silica surface enough to react with bifunctional linker without destroying activity of biomolecule.

A Rh(III)-catalyzed C-H activation reaction has been developed for the preparation of pyridinium salts from secondary allylamines and internal alkynes. The pyridinium salts formed by this N-annulation reaction have interesting fluorescence properties. This protocol has been applied to the surface modification of mesoporous silica materials to generate functionalized silica that can be used for the detection of nitrobenzene.

Chelation-assisted Rh(I)-catalyzed ketone synthesis from allylic alcohols and alkenes through C–H and C–C bond activations under microwave irradiation was developed. Aldimine is formed via olefin isomerization of allyl alcohol under Rh(I) catalysis and condensation with 2-amino-3-picoline, followed by continuous C–H and C–C bond activations to produce a dialkyl ketone. The addition of piperidine accelerates the reaction rate by promoting aldimine formation under microwave conditions.

A new cascade double N-annulation method has been developed for the synthesis of benzoquinolizinium salts. The process takes place between allylamines, internal alkynes, and HBF4 in the presence of Rh(III)/Cu(II) complexes and leads to formation of multisubstituted benzoquinolizinium salts. Importantly, the resulting benzoquinolizinium salts serve as fluorescent materials whose emission wavelengths can be tuned by selection of appropriate substituents.

Structure-based targeting of fluorescent dyes is essential for their use as imaging agents for disease diagnosis. Here, we describe the development of the benzoquinolizinium compound Medical fluorophore 1 (MF1) as a novel biomedical imaging agent that allows the visualization of inflammation by virtue of its unique chemical structure. Lipopolysaccharide treatment stimulated the uptake of MF1 by bone marrow-derived macrophages, with no adverse effects on cell proliferation. In vivo fluorescence lifetime imaging revealed the accumulation of MF1 in carrageenan-induced acute inflammatory lesions in mice, which peaked at 6 h. MF1-based imaging also allowed monitoring of the response to the anti-inflammatory drugs dexamethasone and sulfasalazine. Thus, MF1 can be used to diagnose diseases characterized by inflammation as well as treatment efficacy.

Rh(iii)/Cu(OAc)2 catalyzed, one-pot reactions of aryl ketones, acrylate esters and ammonium acetate or α-substituted benzylamines under microwave irradiation conditions produce 1H-isoindoles bearing a quarternary carbon center.

A methallylsilane coupling reagent, containing both a N-hydroxysuccinimidyl(NHS)-ester group and a UV/vis absorbing azobenzene linker undergoes acid-catalyzed immobilization on silica. Analysis of the UV/vis absorption band associated with the azobenzene group in the adduct enables facile quantitative determination of the extent of loading of the NHS groups. Reaction of NHS-groups on the silica surface with amine groups of GOx and rhodamine can be employed to generate enzyme or dye-immobilized silica for quantitative analysis.

A new method for chlorination of alcohols and carboxylic acids, using α,α-dichlorodiphenylmethane as the chlorinating agent and FeCl3 as the catalyst, was developed. The method enables conversions of various alcohols and carboxylic acids to their corresponding alkyl and acyl chlorides in high yields under mild conditions. Particulary interesting is the observation that the respective alkyl bromides and iodides can be generated from alcohols when either LiBr or LiI are present in the reaction mixtures.

Furans and pyrroles are prepared from 1-alkynes by using a Cu(II)-promoted, one-pot, microwave irradiation method. Glaser coupling of 1-alkynes and cyclization of the resulting 1,3-diyne in the presence of an anhydride or a primary amine results in the formation of the respective 2,5-diaryl- or 2,5-dialkyl-substituted furans and pyrroles.

A new hydrothermally stable Al polycarboxylate metal-organic framework (MOF) based on a heteroatom bio-derived aromatic spacer is designed through a template-free green synthesis process. It appears that in some test conditions this MOF outperforms the heat reallocation performances of commercial SAPO-34.

A reducible metal-organic framework (MOF), iron(III) trimesate, denoted as MIL-100(Fe), was investigated for the separation and purification of methane/ethane/ethylene/acetylene and an acetylene/CO2 mixtures by using sorption isotherms, breakthrough experiments, ideal adsorbed solution theory (IAST) calculations, and IR spectroscopic analysis. The MIL-100(Fe) showed high adsorption selectivity not only for acetylene and ethylene over methane and ethane, but also for acetylene over CO2 . The separation and purification of acetylene over ethylene was also possible for MIL-100(Fe) activated at 423 K. According to the data obtained from operando IR spectroscopy, the unsaturated Fe(III) sites and surface OH groups are mainly responsible for the successful separation of the acetylene/ethylene mixture, whereas the unsaturated Fe(II) sites have a detrimental effect on both separation and purification. The potential of MIL-100(Fe) for the separation of a mixture of C2 H2 /CO2 was also examined by using the IAST calculations and transient breakthrough simulations. Comparing the IAST selectivity calculations of C2 H2 /CO2 for four MOFs selected from the literature, the selectivity with MIL-100(Fe) was higher than those of CuBTC, ZJU-60a, and PCP-33, but lower than that of HOF-3.

A new method for introducing robustly bound organic functional groups on silica surfaces is developed. Compared to conventional monomer immobilization procedures, the new vinylsilane-impregnated polymer based protocol can be employed for the preparation of various organic group functionalized silicas that are stable under both acidic and basic conditions. Organic functional groups can be readily introduced by one-step Rh(I)-catalyzed hydroacylation reaction or appended by Suzuki coupling reactions.

A method for the transition metal catalyzed modification of polybutadiene was developed. Specifically, reactions of polybutadiene with alcohols and sodium formate in the presence of Ru3(CO)12 and 2-pyridinemethanol produce ester derivatives of polybutadiene. By using this approach, selected ratios of mixed ester derivatives of polybutadiene can be produced by employing the corresponding ratio of alcohols.

High quality crystalline Co-CUK-1 can be synthesized rapidly and efficiently by a microwave-assisted method. The resulting microporous coordination material is a highly effective adsorbent for the separation of xylene isomers and ethylbenzene, as demonstrated here through sorption isotherm analysis, Ideal Adsorbed Solution Theory (IASI) calculations, and grand canonical Monte Carlo (GCMC) simulations. Co-CUK-1 showed high sorption capacity and high adsorption selectivity for p-xylene over the corresponding m- and o-isomers, and ethylbenzenes. According to the data obtained from IAST and GCMC simulations, the Co-CUK-1 is found to strongly favour p-xylene adsorption because p-xylene molecules undergo well-defined molecular packing in the 1-D channels; by comparison, the packing efficiencies of o-xylene, m-xylene and ethylbenzene are significantly lower, as is evidenced by lower saturation capacities.

High quality crystalline Co-CUK-1 can be synthesized rapidly and efficiently by a microwave-assisted method. The resulting microporous coordination material is a highly effective adsorbent for the separation of xylene isomers and ethylbenzene, as demonstrated here through sorption isotherm analysis, Ideal Adsorbed Solution Theory (IAST) calculations, and grand canonical Monte Carlo (GCMC) simulations. Co-CUK-1 showed high sorption capacity and high adsorption selectivity for p-xylene over the corresponding m- and o-isomers, and ethylbenzenes. According to the data obtained from IAST and GCMC simulations, the Co-CUK-1 is found to strongly favour p-xylene adsorption because p-xylene molecules undergo well-defined molecular packing in the 1-D channels; by comparison, the packing efficiencies of o-xylene, m-xylene and ethylbenzene are significantly lower, as is evidenced by lower saturation capacities.

We have investigated the fundamental photophysical properties of surface-bound perylene bisimide (PBI) molecules in a solution-phase at the single-molecule level. By efficient immobilization of single PBIs on glass, we were able to simultaneously monitor fluorescence intensity trajectories, fluorescence lifetimes, and emission spectra of individual PBIs in organic and aqueous media using confocal microscopy. We showed that the fluorescence dynamics of single PBIs in the solution phase is highly dependent on their local and chemical environments. Furthermore, we visualized different spatial-fluctuations of surface-bound PBIs using defocused wide-field imaging. While PBIs show more steric flexibility in organic media, the flexible motion of PBI molecules in aqueous solution is relatively prohibited due to a cage effect by a hydrogen bonding network, which is previously unobserved. Our method opens up a new possibility to investigate the photophysical properties of multi-chromophoric systems in various solvents at the single-molecule level for developing optimal molecular devices such as water-proof devices.

A new cascade double N-annulation method has been developed for the synthesis of benzoquinolizinium salts. The process takes place between allylamines, internal alkynes, and HBF

Transition-metal-catalyzed activation of C–H and C–C bonds is a challenging area in synthetic organic chemistry. Among various methods to accomplish these processes, the approach using metal–organic cooperative catalytic systems is one of the most promising. In this protocol, organic molecules as well as transition metals act as catalysts to bring about reactions, which proceed with high efficiencies and selectivities. Various metal–organic cooperative catalytic systems developed for C–H and C–C bond activation reactions are discussed in this review. Also discussed are how each metal–organic cooperative catalyst affects the reaction mechanism and what kinds of substrates can be applied in each of the catalytic processes.

Aryl chlorides in the presence of Pd/C catalyst and NaF react with primary alcohols to form esters, arenes, and alkanes. In this reaction, aryl chlorides act as both oxidants and coupling partners, whereas alcohols serve as both carbonyl sources and alkoxy components of the ester products

Microwave-assisted, tetrabutylammonium hydroxide catalysed 1,4-addition reactions of water to α,β-unsaturated ketones and α,β-ynones take place efficiently in water. Reactions of the resulting β-hydroxy ketones lead to the formation of either C–C bond cleavage or annulation products.

The titanium-based metal–organic framework MIL-125 and its amine-functionalized analog, MIL-125_NH2, have been synthesized and characterized by elemental analysis, XRD, SEM, TEM, N2 adsorption measurements, and spectroscopic techniques, including FTIR, Raman, and DR UV/Vis spectroscopy. Catalytic properties of MIL-125 and MIL-125_NH2 were evaluated in the selective oxidation of two representative alkyl-substituted phenols, 2,3,6-trimethylphenol and 2,6-di-tert-butylphenol, with the clean oxidant H2O2. With both MIL-125 and MIL-125_NH2, the selectivity toward the corresponding p-benzoquinones was 100 %. Samples of MIL-125 with different sizes of crystallites (0.5, 1.5, and 5 μm) demonstrated similar reaction rates, thus indicating the absence of diffusion limitations. The efficiency of the oxidant utilization and stability of the MIL-125 structure increased upon decreasing the amount of water in the reaction mixture. Even if the structural integrity of MIL-125 was destroyed by the reaction medium, the metal–organic framework acted as a precursor for the highly active, selective, and recyclable catalyst. The MIL-125-derived materials were stable toward titanium leaching, behaved as true heterogeneous catalysts, and could easily be recovered by filtration and reused several times without the loss of the catalytic properties.

A new rhodium(III)-catalyzed N-annulation reaction of benzylamines with internal alkynes has been developed. Observations made during these efforts suggest that the mechanistic pathway followed in this process involves direct participation of benzylamines without their preliminary oxidative dehydrogenation. Moreover, N-annulation reactions of primary benzylamines result in the formation of mixtures of isoquinolines and 8-vinylisoquinolines. Finally, secondary and tertiary benzylamines undergo rhodium(III)-catalyzed N-annulation reactions to generate the respective isoquinolinium and hydroisoquinolinium salt products.

A dual functional chromogenic calix[4]arene that contains both hydroxy azophenols and triazoles for colorimetric sensing and cationic recognition, respectively, has been synthesised. This system was further functionalised with dimethallylsilane to permit grafting to a glass surface. This grafting may be used to produce a surface modified glass slides that act as reusable ion-selective colorimetric sensors. UV–vis spectral studies revealed that this compound is capable of binding the calcium cation in aqueous media and producing an easily detectable colour change. The same is true for the modified surface set-up. For the free receptor in acetonitrile solution, the absorption maximum undergoes a red shift from 390 to 496 nm upon exposure to calcium cations. In the case of the modified surface, exposure to acetonitrile solution of calcium perchlorate leads to a change in colour from orange to red. Washing with acetone serves to remove the metal cations from the calix[4]arene-functionalised glass and restore ...

Rh(III)/Cu(OAc)2 catalyzed, one-pot reactions of aryl ketones, acrylate esters and ammonium acetate or α-substituted benzylamines under microwave irradiation conditions produce 1H-isoindoles bearing a quarternary carbon center.

A novel method for the preparation of amides and phthalimides has been developed. The process involves a palladium catalyzed aminocarbonylation of an aryl halide, using a carbodiimide and formic acid as the carbonyl source. Experimental data suggest that the mechanistic pathway for this process involves in-situ generation of carbon monoxide from the reaction of formic acid with a carbodiimide in the presence of a palladium catalyst. The method can be used to produce a variety of amides and N-substituted phthalimides efficiently.

A carbonylative esterification reaction between aryl bromides and alcohols, promoted by Pd/C and NaF in the presence of oxiranes, has been developed. In this process, oxiranes serve as sources of carbon monoxide by their conversion to aldehydes through a palladium-promoted Meinwald rearrangement pathway. Intramolecular versions of this process serve as methods for the synthesis of lactones and phthalimides.

We demonstrated the fabrication of freestanding zeolitic imidazolate framework 7 (ZIF-7) nanofiber (NF) mats by means of one-step, scalable electrospinning. The formation of ZIF-7 nanoparticles embedded in polymer fibers was unambiguously pinpointed via X-ray diffraction, transmission electron microscopy, and adsorption studies. The NF mats exhibited excellent characteristics, with an average diameter of 245 nm, in the adsorption and desorption of carbon dioxide (CO2); this makes them attractive candidates for gas separation and other selective filtration applications. This excellent property of the ZIF-7 mats was explained by the gate-opening phenomenon of ZIF-7, which yielded a stepwise increase in the overall CO2 uptake capacity. The mechanical strength of the NF mats was also obtained via large-strain uniaxial tensile deformation, which enabled preliminary assessment of the mat's suitability for textiles and membranes in targeting separation and filtration applications with large-area permeability. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43788.

Furans and pyrroles are prepared from 1-alkynes by using a Cu(II)-promoted, one-pot, microwave irradiation method. Glaser coupling of 1-alkynes and cyclization of the resulting 1,3-diyne in the presence of an anhydride or a primary amine results in the formation of the respective 2,5-diaryl- or 2,5-dialkyl-substituted furans and pyrroles.

A carbonylative esterification reaction between aryl bromides and alcohols, promoted by Pd/C and NaF in the presence of oxiranes, has been developed. In this process, oxiranes serve as sources of carbon monoxide by their conversion to aldehydes through a palladium-promoted Meinwald rearrangement pathway. Intramolecular versions of this process serve as methods for the synthesis of lactones and phthalimides.

The hierarchically mesoporous iron(III) trimesate MIL-100(Fe) with a zeolite-MTN topology is known as an advanced functional material that is biocompatible. In this work, the large scale synthesis of MIL-100(Fe) has been achieved by hydrothermal reactions using suitable conditions without HF for the large scale synthesis. Although such conditions are narrow, the concurrent change of iron precursor and increase in the concentration of reaction mixture give rise to a synergetic effect leading to an increase in the crystallinity of F-free MIL-100(Fe). This method, combined with two purification steps (solvent extraction and chemical treatment with NH 4 F) leads to a highly porous F-free material obtained throughout a very high space–time-yield (>1700 kg/m 3 day). Possible formation mechanisms of MIL-100(Fe) under hydrothermal conditions have been proposed in terms of four steps such as hydrolysis, deprotonation, self-assembly, and polycondensation. The resulting material exhibits similar physicochemical properties to those of the one prepared in the presence of HF, except for a slight difference in sorption capacities of gases and liquid vapors corresponding to the difference of pore volume. Regardless of the use of HF, the purified MIL-100(Fe) possesses very high uptakes for both non-polar toluene and polar ethanol probe molecules due to the respective interactions with hydrophilic and hydrophobic sites in the framework. Finally, hydrophobicity measurements confirm that the dehydrated MIL-100(Fe) is more hydrophobic than conventional zeolite beta (SiO 2 /Al 2 O 3 = 25) and commercial iron trimesate (Basolite F300) from BASF SE.

A facile method for the preparation of modified indium tin oxide (ITO) electrodes and their use in amperometric sensing of H2O2 are described. ITO surface was first derivatized by acid-catalyzed grafting of N-hydroxysuccinimidyl-ester-functionalized methallylsilane at room temperature, followed by immobilization of functional materials such as gold nanoparticle and thionine by amide coupling reaction. The modification process was monitored using contact angle, scanning electron microscopy and electrochemical measurements, which revealed the controllability and high efficiency of this modification method. Thionine-modified ITO electrode exhibited excellent electrocatalytic activity towards the reduction and amperometric determination of H2O2, demonstrating the potential of this modification strategy in electrocatalysis and amperometric sensing. Keywords: Indium tin oxide, Methallylsilane, Catalytic grafting, Gold nanoparticles, Thionine, H2O2

A metal-organic framework HKUST-1 or Cu 3 (BTC) 2 was synthesized in mesopores of a COOH functionalized mesostructured cellular silica foam (MCF(M)-COOH), resulting in a hydrophobic nanocomposite. The Cu 3 (BTC) 2 formed in the MCF(M)-COOH has been prepared by a microwave method with sequential incorporation of copper nitrate and 1,3,5-benzenetricarboxylic acid in a water/ethanol mixture containing the MCF(M)-COOH. The nanocomposite was characterized by XRD, BET, FT-IR, TEM and solid state 13 C NMR. The nanocomposite had a higher hydrophobic property than pure Cu 3 (BTC) 2 and MCF(M)-COOH as a result of their hybridization. Moreover, the formation of the nanocomposite increased the sorption rate of cyclohexane vapor as compared with those of pure Cu 3 (BTC) 2 and MCF(M)-COOH due to the increased hydrophobicity.

Three porous Al-BTCs (BTC: benzenetricarboxylate) have been synthesized in wide reaction conditions including heating methods (conventional electric and microwave heating) and reaction time. It has been found that an Al-BTC called MIL-100 converts into another phase (MIL-110) with increasing time and eventually a different phase (MIL-96) is observed. This phase-conversion is the first observation of the possibility to synthesize three MOFs from the very same reactant mixtures, and may be explained with the relative stability of the Al-BTCs (MIL-96 > MIL-110 > MIL-100) since the stability of a porous material may increase with decreasing porosity or pore size of the phases. The inter-conversion of a less stable Al-BTC into a more stable one is carried out via recombination of the degraded precursors. Moreover, due to the advantage of rapid crystallization of microwave heating, it can be found that microwave synthesis selectively leads to highly porous materials like MIL-100 or MIL-110. This phase-selective synthesis with microwaves is similar to the synthesis of another MOFs (Cr-BDCs) and aluminophosphates, and may lead to a new way to synthesize highly porous (unstable) materials.

Novel homocoupling reactions of vinylsilanes, catalyzed by a mixture of Ir(I) and HCl, were developed. This process leads to exclusive formation of head-to-tail vinylsilane dimers in high yields at room temperature. Synthetic attributes of transformations of the resulting head-to-tail vinylsilane dimers and polymerization of bis(vinylsilane) were investigated.

The title reaction of acyclic α,β-unsaturated aldehydes with alkenes leads to two ketone products via 1,4-addition of a primary amine (CyNH2 or hexylamine) to the aldehyde followed by a retro-Mannich-type fragmentation of the resulting β-aminoketimine intermediates.

A one-step grafting method of NHS-ester group is described for the immobilization of enzymes onto a silica surface at room temperature. Pure NHS-ester functionalized methallylsilane was prepared as a grafting reagent and showed remarkable grafting efficiency with acid catalysts at room temperature. As a result, mesoporous silica balls bearing a covalently immobilized enzyme could be obtained with a high loading rate compared to conventional multistep grafting methods. This one-step procedure offers the advantages of precise measurement of the high loading efficiency of the NHS-ester group, and the exclusive formation of only the NHS-ester group, which reduces the presence of unreacted functionalities.

New methallylsilanated phosphorylcholine (MASPCs) were synthesized via a copper-catalyzed ‘click’ reaction and demonstrated excellent moisture stability. Hydroxylated silicon compounds, silanol, and silica were grafted or modified by MASPCs in the presence of triflic acid (TfOH) and they possessed a good grafting efficiency and high loading rate.

Novel Au25(C6S)17PyS clusters (pyrene-functionalized Au25 clusters) showing interesting electrochemical and optical properties are synthesized and characterized. Significant fluorescence quenching is observed for pyrene attached to Au25 clusters, suggesting strong excited-state interactions. Time-resolved fluorescence upconversion and transient absorption measurements are utilized to understand the excited-state dynamics and possible interfacial electron- and energy-transfer pathways. Electrochemical investigations suggest the possibility of electron transfer from Au25 clusters to the attached pyrene. Fluorescence upconversion measurements have shown faster luminescence decay for the case of pyrene attached to Au25 clusters pointing toward ultrafast photoinduced electron/energy-transfer pathways. Femtosecond transient absorption measurements have revealed the presence of the anion radical of pyrene in the excited-state absorption, suggesting the directional electron transfer from Au25 clusters to pyrene. ...

Catalytic C–C double bond cleavage of α,β-enones with a 1-alkene and H 2 O was carried out in the presence of a (Ph 3 P) 3 RhCl catalyst, 2-amino-3-picoline, cyclohexylamine, benzoic acid, and alkyl group-immobilized silica spheres. Upon completion of the reaction, the corresponding ketones were obtained without needing a further hydrolysis step. In this reaction, alkyl group-immobilized silica spheres act as a water reservoir for hydrolysis of an intermediate ketimine and as a phase divider between the organic solution and H 2 O.