The reduction of surface "native" oxides from GaAs substrates following reactions with trimethylaluminum ͑TMA͒ precursor is studied using medium energy ion scattering spectroscopy ͑MEIS͒ and x-ray photoelectron spectroscopy ͑XPS͒. MEIS measurements after one single TMA pulse show that ϳ65% of the native oxide is reduced, confirmed by XPS measurement, and a 5 Å thick oxygen-rich aluminum oxide layer is formed. This reduction occurs upon TMA exposure to as-received GaAs wafers.

Using air as the oxidant instead of the traditionally employed persulfates, the smaller and more uniform Pd nanoparticles (around 2 nm) supported on polyaniline (Pd@PANI) can be easily fabricated by the oxidation-polymerization of aniline with PdCl2. This material is an efficient and environmentally friendly catalyst for Heck reactions due to its recyclability, low loading, and ligand-free and mild reaction conditions. It was even tolerant to sulfur-containing substrates. This work reports the Pd@PANI-catalyzed Heck reactions with very wide substrate scopes, and discloses the catalytic mechanisms based on experimental findings and results of catalyst analysis and characterization.

Hexavalent Se? Yes! Selenium on polymers exhibits quite different properties compared to that in small molecules. Hexavalent Se, rare in organoselenium chemistry, was found to be the major species on polymers. The high-valent Se species on recyclable polymer resins could quickly catalyze the oxidation reaction of cyclohexene with H 2 O 2 in water to produce industrially important intermediate trans-1,2cyclohexanediol in almost quantitative yield. In the catalytic cycle, high valent Se species were reduced to divalent Se, a highly activated species that could be re-oxidized by air so that no excess H 2 O 2 was required for the reaction. The results were superior to those of reactions catalyzed by small molecules, for which excess H 2 O 2 , long reaction time or expensive CF 3 -activated catalysts and environmentally unfriendly MeCN solvent were required.

In addition to the significance of photocatalytic hydrogen evolution, the utilization of the in situ generated H/D (deuterium) active species from water splitting for artificial photosynthesis of high value‐added chemicals is very attractive and promising. Herein, photocatalytic water splitting technology is utilized to generate D‐active species (i.e., Dad) that can be stabilized on anchored 2nd metal catalyst and are readily for tandem controllable deuterations of carbon–carbon multibonds to produce high value‐added D‐labeled chemicals/pharmaceuticals. A highly crystalline K cations intercalated polymeric carbon nitride (KPCN), rationally designed, and fabricated by a solid‐template induced growth, is served as an ultraefficient photocatalyst, which shows a greater than 18‐fold enhancement in the photocatalytic hydrogen evolution over the bulk PCN. The photocatalytic in situ generated D‐species by superior KPCN are utilized for selective deuteration of a variety of alkenes and alkynes by anchored 2nd catalyst, Pd nanoparticles, to produce the corresponding D‐labeled chemicals and pharmaceuticals with high yields and D‐incorporation. This work highlights the great potential of developing photocatalytic water splitting technology for artificial photosynthesis of value‐added chemicals instead of H2 evolution.

Areneselenenic acids (ArSeOH), readily generated from diaryl diselenides and H2O2 by in situ oxidation, were found to be effective and reusable catalysts for dehydration of aldoximes, leading to a practical and scalable preparation of useful organonitriles under mild conditions.

A redox‐relay migratory hydroarylation of isomeric mixtures of olefins with arylboronic acids catalyzed by nickel complexes bearing diamine ligands is described. A range of structurally diverse 1,1‐diarylalkanes, including those containing a 1,1‐diarylated quaternary carbon, were obtained in excellent yields and with high regioselectivity. Preliminary experimental evidence supports the proposed non‐dissociated chainwalking of aryl‐nickel(II)‐hydride species along the alkyl chain of alkenes before selective reductive elimination at a benzylic position. A catalyst loading as low as 0.5 mol % proved to be sufficient in large‐scale synthesis while retaining high reactivity, highlighting the practical value of this transformation.

2-Methylenecyclobutanones (2-MCBones), used to be difficult to access, but can now be easily achieved by a green and stereospecific Ca(OH) 2 -catalyzed direct and simple aldol condensation of cyclobutanone and aldehydes under mild conditions. The obtained (E)-2-MCBones should be a class of potentially useful building blocks in synthesis as they could readily undergo an interesting (PhSe) 2 -catalyzed Baeyer-Villiger (BV) oxidation with H 2 O 2 at room temperature to give the versatile 4-methylenebutanolides. Mechanistic studies revealed that the BV reaction most possibly proceeded via the initial formation of benzeneseleninoperoxoic anhydride [PhSe(O)O] 2 O, which then converted to benzeneseleninoperoxoic acid PhSe(O)OOH as the active oxidant, followed by its selective addition to the CvO bond of 2-MCBones and then a selective C-C bond cleavage and rearrangement to give 4-methylenebutanolides.Scheme 1 Three structurally-related building blocks. † Electronic supplementary information (ESI) available: Detailed experimental procedures, condition screening tables, characterization data, 1 H, 13 C NMR and NOESY spectra of the products, and 77 Se NMR spectroscopic studies on the involved organoselenium species. See

This study was conducted to investigate the effects of in ovo feeding (IOF) of Arg solution on the hatchability, growth performance, gastrointestinal hormones, serum AA, activities of digestive enzymes, and mRNA expressions of sensing receptors and nutrient transporters in the jejunum of posthatch broilers. One thousand two hundred embryonated eggs with similar weight were randomly allocated to 5 groups consisting of 8 replicates of 40 eggs each. The 5 treatments were arranged as a noninjected control, a diluent-injected (0.75% NaCl solution) group, and Arg solution-injected groups with 0.5%, 1.0%, and 2.0% Arg, all dissolved in diluent. At 17.5 d of incubation, 0.6 mL of IOF solution was injected into the amniotic fluid of each egg of the injected groups. Results showed the hatchability of the 2% Arg group was lower (linear, = 0.025) than that of the other groups, and the BW of 21-d-old broilers increased (linear, = 0.008; quadratic, = 0.003) with increasing IOF concentration of Arg. The ADFI (linear, = 0.005; quadratic, = 0.001) and ADG (linear, = 0.010; quadratic, = 0.004) increased during d 1 to 21 with increasing IOF concentration of Arg. For 7- and 21-d-old broilers, the weights of digestive organs increased (linear, < 0.05) with increasing IOF concentrations of Arg; the greatest values were observed in the 1% Arg group. For 21-d-old broilers, IOF of the 1% Arg solution increased ( < 0.05) the concentrations of ghrelin and glucagon-like peptide 2; the activities of digestive enzymes, alkaline phosphatase, maltase, and sucrase in the jejunum; and the concentrations of serum AA of Val, Met, Ile, Leu, Arg, and Pro compared with those of the noninjected control and diluent-injected group. In ovo feeding of the 1% Arg solution also increased ( < 0.05) the mRNA expressions of jejunal sensing receptors of taste receptor type 1 members 1 and 3; the G protein-coupled receptor, class C, group 6, subtype A; nutrient transporters of solute carrier family 7, members 4, 6, and 7; sodium-glucose transporter 1; and fatty acid-binding protein 1. In conclusion, the 1% Arg solution was the appropriate injection level. In ovo feeding of the 1% Arg solution did not affect the hatchability but facilitated the release of gastrointestinal hormones, increasing the digestive and absorptive capacity and finally improving the growth performance of 21-d-old broilers. Therefore, IOF of the appropriate Arg solution could be an effective technology for regulating early nutrition supply and subsequent growth development in the poultry industry.