Deep eutectic solvents coupled with (NH4)3H6CoMo6O24 trigger aerobic oxidation of 5-hydroxymethylfurfural to 5-formyl-2-furancarboxylic acid.

An Anderson-type polyoxometalate (NH4)3H6CoMo6O24 in deep eutectic solvents exhibited outstanding catalytic performance for the selective aerobic oxidation of HMF to FFCA. It is potentially a promising and highly environmentally friendly approach for biomass conversion.

In Situ Transformation of ZIF-8 into Porous Overlayer on Ru/ZnO for Enhanced Hydrogenation Catalysis.

Supported metal catalysts play a significant role in heterogeneous catalysis in liquid phase reaction systems, but they usually suffer from a stability problem. Encapsulation of active metal species without the compromise of catalytic performance has been considered as an effective strategy. Here, we report an ultrastable Ru-based catalyst with particle size of around 1.1 nm for selective hydrogenation reaction. The highly dispersed Ru species are covered by the in situ formed porous N-C-ZnO overlayer, which is induced through the transforming of ZIF-8 shell that derives from a ZnO substrate. The resulting Ru/ZnO@N-C-ZnO catalyst can exhibit good stability in the hydrogenation of p-chloronitrobenzene after 20 cyclic runs with 100% selectivity toward p-chloroaniline. Comparatively, the naked Ru/ZnO catalyst with larger Ru particles shows serious metal leaching issue with inferior stability and poor selectivity. It is revealed that the excellent performance of Ru/ZnO@N-C-ZnO is attributed to the porous overlayer, which strengthens the bonding of Ru nanoparticles on ZnO.

A novel Zn-Al spinel-alumina composite supported gold catalyst for efficient CO oxidation.

A spinel-alumina inert oxide supported gold catalyst with high Au dispersion and excellent CO oxidation activity was developed by a deposition-precipitation method. The activation atmosphere could tune the reaction pathway by adjusting the amount of surface adsorbed water species, thus transforming the reaction intermediates from HCO3- or CO32- to COOH.

Enhancing the stability of the Rh/ZnO catalyst by the growth of ZIF-8 for the hydroformylation of higher olefins.

Hydroformylation of olefins is one of the most important industrial processes for aldehyde production. Therein, the leaching of active metals for heterogeneous catalysts is an important issue in the hydroformylation reaction, particularly for higher olefins to produce higher alcohols. Here, different Rh/ZnO catalysts with diverse ZnO as a support were investigated and a home-made ZnO50 support was selected to prepare the Rh/ZnO50@ZIF-8 core-shell structure catalyst, which was synthesized by the growth of ZIF-8 with ZnO50 as the sacrificed template to afford Zn source. Compared with the Rh/ZnO50 catalyst, the Rh/ZnO50@ZIF-8 catalyst demonstrated a better cyclic stability in the hydroformylation of 1-dodecene. Combining the experiment and characterization results, it was concluded that the ZIF-8 shell on the Rh/ZnO50 catalyst effectively prevented the leaching of metal Rh into the reaction solution. Moreover, the Rh/ZnO50@ZIF-8 catalyst exhibited good universality for other higher olefins. This work provides a useful guideline for immobilizing the active species in heterogeneous catalysts for the hydroformylation reaction.

Choline chloride-based deep eutectic solvents for efficient cycloaddition of CO2 with propylene oxide.

Choline chloride-based deep eutectic solvents (DESs) exhibited remarkable activity in the cycloaddition of CO2 with propylene oxide (PO) in the absence of any additives under solvent- and metal-free conditions as well as recyclability.

L-proline-based deep eutectic solvents (DESs) for deep catalytic oxidative desulfurization (ODS) of diesel.

A series of L-proline-based DESs was prepared through an atom economic reaction between L-proline (L-Pro) and four different kinds of organic acids. The DESs were characterized by Fourier transform infrared spectroscopy (FT-IR), H nuclear magnetic resonance (1HNMR), cyclic voltammogram (CV) and the Hammett method. The synthesized DESs were used for the oxidative desulfurization and the L-Pro/p-toluenesultonic acid (L-Pro/p-TsOH) system shows the highest catalytic activity that the removal of dibenzothiophene (DBT) reached 99% at 60°C in 2h, which may involve the dual activation of the L-Pro/p-TsOH. The acidity of four different L-proline-based DESs was measured and the results show that it could not simply conclude that the correlation between the acidity of DESs and desulfurization capability was positive or negative. The electrochemical measurements evidences and recycling experiment indicate a good stability performance of L-Pro/p-TsOH in desulfurization. This work will provide a novel and potential method for the deep oxidation desulfurization.

Deep catalytic oxidative desulfurization (ODS) of dibenzothiophene (DBT) with oxalate-based deep eutectic solvents (DESs).

An oxalate-based DES with a tetrabutyl ammonium chloride and oxalate acid molar ratio of 1/2 (TBO1 : 2) exhibited high activity in oxidative desulfurization (ODS) of dibenzothiophene (DBT) under mild reaction conditions. It is potentially a promising and highly environmentally friendly approach for desulfurization of fuels.

Oxidative desulfurization of model diesel via dual activation by a protic ionic liquid.

A novel and green carboxylate-anion-based protic ionic liquid (PIL), [Hnmp]HCOO, was prepared through a simple and atom economic neutralization reaction between N-methyl-2-pyrrolidonium (NMP) and formic acids. Both FT-IR spectra and (1)H NMR confirmed its simple salt structure. [Hnmp]HCOO exhibited so high catalytic activity that the dibenzothiophene (DBT) removal reached 99% at 50°C in 3h under conditions of VPIL/Vmodel oil=1:10 and H2O2/DBT (O/S, molar ratio)=5. The catalytic oxidation reactivity of S-compounds was found to be in the order of DBT>4,6-dimethyldibenzothiophene (4,6-DMDBT)>benzothiophene (BT). The investigation on mechanism showed that oxidative desulfurization was realized through dual activation of PIL. Moreover, [Hnmp]HCOO can be recycled for five times with an unnoticeable decrease in desulfurization activity.

Surface modification of poly(styrene-b-(ethylene-co-butylene)-b-styrene) (SEBS) elastomer via covalent immobilization of nonionic sugar-based Gemini surfactants.

Gemini surfactants (GS) with sugar-containing head-groups and different alkyl chains were successfully prepared. Poly(styrene-b-(ethylene-co-butylene)-b-styrene) (SEBS) elastomer was grafted with glycidyl methacrylate (GMA) by means of UV-induced graft polymerization, and then the pGMA-grafted film was chemically immobilized with the GS. The surface graft polymerization was confirmed by ATR-FTIR and XPS. The wettability and hemocompatibility of the modified surface were characterized by means of water contact angle, protein adsorption, and platelet adhesion assays. The results showed that amphiphilic surfactant-containing polymer surfaces presented protein-resistant behavior and anti-platelet adhesion after functionalization with GS, GS1 and GS2. Besides, the hemocompatibility of the modified surface deteriorated as the length of hydrophobic chain of GS increased.

Large scale synthesis of highly crystallized SnO2 quantum dots at room temperature and their high electrochemical performance.

In this work, SnO2 quantum dots with high crystallinity were synthesized on a large scale under mild reaction conditions via an epoxide precipitation route. The SnO intermediate, which was produced in the reactions between epoxide and [Sn(H2O)6](2+), was converted to SnO2 quantum dots by the oxidation of H2O2. It is believed that the protonation and the following ring opening of epoxide promoted the hydrolysis and condensation of [Sn(H2O)6](2+) to form the intermediate. The obtained quantum dots had a maximum specific capacitance of 204.4 F g(-1) at a scan rate of 5 mV s(-1) in 1 mol l(-1) KOH aqueous solution. The electrochemical measurements proved that this high specific capacitance of SnO2 resulted from the Faradaic reactions between SnO2 and the electrolyte. This demonstrates for the first time that SnO2 can be used as a pseudocapacitive electrode material.

Surfactant-free synthesis of water-soluble anatase nanoparticles and their application in preparation of high optic performance monoliths.

Highly water-soluble 2nm anatase nanoparticles were synthesized under mild conditions via a simple, scalable and surfactant-free sol-gel method. The covalent bonding of butoxy groups with surface Ti ions prevents mutual contact of surface hydroxyl groups between particles, leading to the weak inter-linkage of particles in powder. As a result, the obtained powder can be easily dissolved in water just by gentle shaking of container because of the formation of hydrogen bonds between water molecules and surface hydroxyl groups of particles. Originated from the water soluble property of TiO2 nanoparticles, polishable TiO2-SiO2 composite monoliths were prepared for application in UV-shielding. The obtained monolith shows high transparency in visible range and excellent absorption efficiency in UV band.

Diethyl 2,2-bis-(3,5-di-tert-butyl-4-hy-droxy-benz-yl)malonate.

The title mol-ecule, C(37)H(56)O(6), possesses twofold symmetry, with the twofold axis passing through the quaternary C atom. In the crystal, neighbouring mol-ecules are linked via O-H⋯O hydrogen bonds involving the phenol OH group and the carbonyl O atom, forming chains propagating in [101]. Within these chains, rings are formed with an R(2) (2)(20) motif. There are also C-H⋯O inter-actions present within the rings.

Strategies of large scale synthesis of monodisperse nanoparticles.

Intensive research focuses on the development of nanoparticles, not only for their fundamental scientific interest, but also for a variety of technological applications. Monodisperse nanoparticles with a size variation of less than 5% exceptionally have been received much attention, due to their novel and high performance induced by the strong dependence of properties upon the dimension of the nanoparticles. Their unique properties result in a great of potential applications in the area of ultra-high density magnetic storage media, electronics, biomedical usage, medical diagnosis, catalyst, etc. This is stimulating a high level of interest in the development of large scale synthesis techniques of monodisperse nanoparticles. In this article, the recent advance about the relevant aspects of large scale synthesis approaches for various monodisperse nanoparticles was summarized.

Bis(1,2,2,6,6-penta-methyl-piperidin-4-yl) 2-butyl-2-(3,5-di-tert-butyl-4-hydroxy-benz-yl)malonate (Tinuvin 144).

The title compound, C(42)H(72)N(2)O(5), a hindered amine light stabiliser (HALS) with the trade name Tinuvin 144 was prepared from bis-(1,2,2,6,6-penta-methyl-piperidin-4-yl) 2-butyl-malonate and 2,6-di-tert-butyl-4-[(dimethyl-amino)meth-yl]phenol using lithium amide as a catalyst. In the mol-ecule, both piperidine rings adopt chair conformations. In the crystal, inversion dimers linked by pairs of O-H⋯O hydrogen bonds occur.

Dimethyl 2-butyl-2-(3,5-di-tert-butyl-4-hydroxy-benz-yl)malonate.

The title compound, C(25)H(38)O(5), was formed by the reaction of dimethyl 2-butyl-malonate and 2,6-di-tert-butyl-4-[(dimethyl-amino)meth-yl]phenol. In the crystal structure, mol-ecules are linked by inter-molecular O-H⋯O hydrogen bonds into chains along [010].

2,6-Di-tert-butyl-4-(morpholinometh-yl)-phenol monohydrate.

In the title compound, C(19)H(31)NO(2)·H(2)O, the morpholine ring adopts a chair conformation, while the phenolic hydroxyl group is sterically hindered by the adjacent tert-butyl groups. The crystal structure is stabilized by a number of O-H⋯O, O-H⋯N and C-H⋯O hydrogen-bonding inter-actions, involving both the organic and the solvent mol-ecules.

4-Chloro-N-methyl-6-(morpholin-4-yl)-N-phenyl-1,3,5-triazin-2-amine.

In the title compound, C(14)H(16)ClN(5)O, the phenyl and triazine rings form a dihedral angle of 69.34 (8)°. The morpholine ring adopts a chair conformation. The structure is stabilized by C-H⋯N and intermolecular C-H⋯O hydrogen-bonding inter-actions.