Selective hydrosilylation of allyl chloride with trichlorosilane.

The transition-metal-catalysed hydrosilylation reaction of alkenes is one of the most important catalytic reactions in the silicon industry. In this field, intensive studies have been thus far performed in the development of base-metal catalysts due to increased emphasis on environmental sustainability. However, one big drawback remains to be overcome in this field: the limited functional group compatibility of the currently available Pt hydrosilylation catalysts in the silicon industry.

Effects of Fiber Stiffening to a Soft Actuator with PEDOT/PSS Electrode Films on Actuation Cycling Stability.

In this work, we fabricated a fiber-stiffened soft actuator with PEDOT/PSS films as electrode. Embedding nylon fibers in the soft actuator successfully suppressed twisting deformations, resulting in a large and persistent actuation displacement. We evaluated the effects of the fiber spacing (1, 2, 3 and 4 mm) on the displacement and assessed the actuation displacement as a function of applied voltage (0.

Stereoretentive N-Arylation of Amino Acid Esters with Cyclohexanones Utilizing a Continuous-Flow System.

The N-arylation of chiral amino acid esters with minimal racemization is a challenging transformation because of the sensitivity of the α-stereocenter. A versatile synthetic method was developed to prepare N-arylated amino acid esters using cyclohexanones as aryl sources under continuous-flow conditions. The designed flow system, which consists of a coil reactor and a packed-bed reactor containing a Pd(OH) /C catalyst, efficiently afforded the desired N-arylated amino acids without significant racemization, accompanied by only small amounts of easily removable co-products (i.

Porous intermetallic NiXAl (X = Ti or Zr) nanoparticles prepared from oxide precursors.

Porous intermetallic NiXAl (X = Ti or Zr) nanoparticles with small crystallite sizes (24-34 nm) and high Brunauer-Emmett-Teller (BET) surface areas (10-71 m g) were prepared from oxide precursors by a chemical route. CaH acted as a template to form the porous morphologies and assisted the reduction.

Catalytic Hydrogenation of CO to Methanol Using Multinuclear Iridium Complexes in a Gas-Solid Phase Reaction.

We report a novel approach toward the catalytic hydrogenation of CO to methanol performed in the gas-solid phase using multinuclear iridium complexes at low temperature (30-80 °C). Although homogeneous CO hydrogenation in water catalyzed by amide-based iridium catalysts provided only a negligible amount of methanol, the combination of a multinuclear catalyst and gas-solid phase reaction conditions led to the effective production of methanol from CO. The catalytic activities of the multinuclear catalyst were dependent on the relative configuration of each active species.

Pt-Catalyzed selective oxidation of alcohols to aldehydes with hydrogen peroxide using continuous flow reactors.

The oxidation of alcohols to aldehydes is a powerful reaction pathway for obtaining valuable fine chemicals used in pharmaceuticals and biologically active compounds. Although many oxidants can oxidize alcohols, only a few hydrogen peroxide oxidations can be employed to continuously synthesize aldehydes in high yields using a liquid-liquid two-phase flow reactor, despite the possibility of the application toward a safe and rapid multi-step synthesis. We herein report the continuous flow synthesis of (E)-cinnamaldehyde from (E)-cinnamyl alcohol in 95%-98% yields with 99% selectivity for over 5 days by the selective oxidation of hydrogen peroxide using a catalyst column in which Pt is dispersed in SiO2.

Treating octasilanol [SiO][OH] with tetramethoxysilane and trimethoxyvinylsilane: a halogen-free synthetic route to alkoxysilyl-substituted double-four-ring siloxanes.

The synthesis of methoxysilyl-substituted siloxanes with a double-four-ring (D4R) framework [Si8O12][OSiR(OMe)2]8 (R = OMe or vinyl) via the dealcoholative coupling between silanol [Si8O12][OH]8 and alkoxysilane was accomplished and achieved a halogen-free synthetic process. The solid-state structure of [Si8O12][OSi(OMe)3]8 was determined via a single-crystal X-ray diffraction analysis.

Rapid and continuous fabrication of TiO nanoparticles encapsulated by polyimide fine particles using a multistep flow-system and their application.

PI fine particles encapsulating a large number of TiO nanoparticles (PI FPs/TiO NPs) were successfully fabricated rapidly and continuously by the emulsion re-precipitation method using a multistep flow synthetic system. The fabricated material, PI FPs/TiO NPs, was spherical in structure with a diameter of 214 nm, and the mean size of TiO NPs was 5.2 nm.

A General and Selective Synthesis of Methylmonochlorosilanes from Di-, Tri-, and Tetrachlorosilanes.

Direct catalytic transformation of chlorosilanes into organosilicon compounds remains challenging due to difficulty in cleaving the strong Si-Cl bond(s). We herein report the palladium-catalyzed cross-coupling reaction of chlorosilanes with organoaluminum reagents. A combination of [Pd(CH)Cl] and DavePhos ligand catalyzed the selective methylation of various dichlorosilanes , trichlorosilanes , and tetrachlorosilane to give the corresponding monochlorosilanes.

NO decomposition properties of Ru catalysts supported on various oxide materials and SnO.

Nitrous oxide (NO) is a stratospheric ozone depleting greenhouse gas that has global warming potential. As the catalytic decomposition of NO is one of the most promising techniques for NO emissions abatement, in this study, for this purpose the properties of Ru supported on various oxide materials were investigated under excess O conditions, and the identities of the NO adsorption species on the catalysts were confirmed. To clarify the correlation between the catalytic properties and NO decomposition activity, the supported Ru catalysts were characterised by means of powder X-ray diffraction, X-ray fluorescence measurements, energy-dispersive X-ray mapping and several gas sorption techniques.

Efficient transfer of DNP-enhanced H magnetization to half-integer quadrupolar nuclei in solids at moderate spinning rate.

We show herein how the proton magnetization enhanced by dynamic nuclear polarization (DNP) can be efficiently transferred at moderate magic-angle spinning (MAS) frequencies to half-integer quadrupolar nuclei, S ≥ 3/2, using the Dipolar-mediated Refocused Insensitive Nuclei Enhanced by Polarization Transfer (D-RINEPT) technique, in which a symmetry-based recoupling scheme built from adiabatic inversion H pulses reintroduces the H-S dipolar couplings, while suppressing the H- H ones. The use of adiabatic pulses also improves the robustness to offsets and radiofrequency (rf)-field inhomogeneity. Furthermore, the efficiency of the polarization transfer is further improved by using H composite pulses and continuous-wave irradiations between the recoupling blocks, as well as by manipulating the S satellite transitions during the first recoupling block.

Sustainable Catalytic Synthesis of Diethyl Carbonate.

New sustainable approaches should be developed to overcome equilibrium limitation of dialkyl carbonate synthesis from CO and alcohols. Using tetraethyl orthosilicate (TEOS) and CO with Zr catalysts, we report the first example of sustainable catalytic synthesis of diethyl carbonate (DEC). The disiloxane byproduct can be reverted to TEOS.

Antihyperuricemic Effect of Urolithin A in Cultured Hepatocytes and Model Mice.

Hyperuricemia is defined as a disease with high uric acid (UA) levels in the blood and a strong risk factor for gout. Urolithin A (UroA) is a main microbial metabolite derived from ellagic acid (EA), which occurs in strawberries and pomegranates. In this study, we evaluated antihyperuricemic effect of UroA in both cultured hepatocytes and hyperuricemic model mice.

Co(I) complexes with a tetradentate phenanthroline-based PNNP ligand as a potent new metal-ligand cooperation platform.

A series of low spin cobalt(i) complexes bearing a tetradentate phenanthroline-based PNNP ligand (2,9-bis((diphenylphosphanyl)methyl)-1,10-phenanthroline), [CoCl(PNNP)] (1), [CoMe(PNNP)] (2) and [Co(CH2SiMe3)(PNNP)] (3), were synthesized and structurally identified. Complex 3 underwent a structural rearrangement of the PNNP skeleton upon heating to form [Co(PNNP')] (4), which is supported by an asymmetrical PNNP' ligand with a dearomatized phenanthroline backbone. Mechanistic studies supported that the transformation from 3 to 4 was initiated by the homolysis of either a Co-CH2SiMe3 bond or a benzylic C-H bond.

Improving thermal and mechanical properties of biomass-based polymers using structurally ordered polyesters from ricinoleic acid and 4-hydroxycinnamic acids.

Biomass-based copolymers with alternating ricinoleic acid and 4-hydroxycinnamic acid derivatives (-coumaric acid, ferulic acid, and sinapinic acid) exhibit a repeating structure based on soft and hard segments, derived from ricinoleic and 4-hydroxycinnamic acids, respectively. To achieve this alternating sequence, copolymers were synthesised by the self-condensation of hetero-dimeric monomers derived by the pre-coupling of methyl ricinolate and 4-hydroxycinnamic acid. The glass transition temperature ( ) was observed to increase as the number of methoxy groups on the main chain increased; the values of poly(coumaric acid--ricinoleic acid), poly(ferulic acid--ricinoleic acid), and poly(sinapinic acid--ricinoleic acid) are -15 °C, -4 °C, and 24 °C respectively, 58 °C, 69 °C, and 97 °C higher than that of poly(ricinoleic acid).

Allyl Monitorization of the Regioselective Pd-Catalyzed Annulation of Alkylnyl Aryl Ethers Leading to Bismethylenechromanes.

The mechanism for the synthesis of 2,3-bismethylenechromanes obtained by the reaction between silylethynyloxyarenes and allylic pivalates and catalyzed by a palladium complex has been investigated using computational methods rooted in density functional theory. The reaction is promoted by a C-H bond activation and the consequent bond cleavage of both substrates, followed by a novel annulation. The whole mechanism of this reaction is described together with the drawbacks that could block it.

Emotional Impairments and Neuroinflammation are Induced in Male Mice Invulnerable to Repeated Social Defeat Stress.

Prolonged stress triggers neuroinflammation, which plays a significant role in the development of depression; however, stressed people do not always suffer from depression because of individual differences in stress vulnerability. Negative cognitive bias (NCB) toward pessimistic judgment often underlies depressive episodes. However, a relationship between stress vulnerability, neuroinflammation, and NCB remains elusive.

Cooperative Effects of Heterodinuclear Ir-M Complexes on Catalytic H Evolution from Formic Acid Dehydrogenation in Water.

Novel heterodinuclear Ir-M complexes (M = Co, Ni, or Cu) with two adjacent reaction sites were synthesized by using 3,5-bis(2-pyridyl)-pyrazole (Hbpp) as a structure-directing ligand and employed as catalysts for H evolution through formic acid dehydrogenation in water. A cooperative effect of the hetero-metal centers was observed in the H evolution in comparison with the corresponding mononuclear Ir and M complexes as the components of the Ir-M complexes. The H evolution rate for the Ir-M complexes was at most 350-fold higher than that of the mononuclear Ir complex.

Continuous Synthesis of Aryl Amines from Phenols Utilizing Integrated Packed-Bed Flow Systems.

Aryl amines are important pharmaceutical intermediates among other numerous applications. Herein, an environmentally benign route and novel approach to aryl amine synthesis using dehydrative amination of phenols with amines and styrene under continuous-flow conditions was developed. Inexpensive and readily available phenols were efficiently converted into the corresponding aryl amines, with small amounts of easily removable co-products (i.

Skewed electronic band structure induced by electric polarization in ferroelectric BaTiO.

Skewed band structures have been empirically described in ferroelectric materials to explain the functioning of recently developed ferroelectric tunneling junction (FTJs). Nonvolatile ferroelectric random access memory (FeRAM) and the artificial neural network device based on the FTJ system are rapidly developing. However, because the actual ferroelectric band structure has not been elucidated, precise designing of devices has to be advanced through appropriate heuristics.

A catalyst- and additive-free synthesis of alkoxyhydrosiloxanes from silanols and alkoxyhydrosilanes.

A convenient method for the selective synthesis of alkoxyhydrosiloxanes that bear SiH and SiOR groups on the same silicon atom, RSi-O-SiR(OR)H (n = 0, 1, or 2), via a simple catalyst- and additive-free dealcoholization reaction between silanols and alkoxyhydrosilanes has been developed. These alkoxyhydrosiloxanes can be easily converted into Si(OR)-containing siloxanes by zinc catalyzed alkoxylation and alkoxy-containing silphenylene polymers by platinum catalyzed hydrosilylation.

Polypropylene-Based Nanocomposite with Enhanced Aging Stability by Surface Grafting of Silica Nanofillers with a Silane Coupling Agent Containing an Antioxidant.

Simultaneous improvement in the mechanical properties and lifetime of polymer nanocomposites is crucially significant to further extend the versatility of polymer materials and reduce environmental impact. In this study, we fabricated reinforced polypropylene (PP)-based nanocomposites with improved aging stability by the addition of surface-modified well-ordered silica nanospheres with a silane coupling agent (SCA) containing hindered phenol antioxidant as a filler. Uniform grafting of the SCA on the filler surface contributed to homogeneous dispersion of the filler into the matrix, leading to improved properties (e.

The Direct Partial Oxidation of Methane to Dimethyl Ether over Pt/Y O Catalysts Using an NO/O Shuttle.

Using a mixture of NO + O as the oxidant enabled the direct selective oxidation of methane to dimethyl ether (DME) over Pt/Y O . The reaction was carried out in a fixed bed reactor at 0.1 MPa over a temperature range of 275-375 °C.