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Phase pure and mesoporous Co3O4 crystals are designed via a simple, cost-effective and single-step co-precipitation method having higher adsorption and uptake capacity intended for elimination of toxic Cr(vi) ions from the aquatic environment.

A highly reactive acid-functionalized polymer is prepared by the simple condensation of aqueous formaldehyde and p-phenolsulfonic acid and used as a solid catalyst in concerted (trans)esterification. This yields biodiesel from Jatropha oil without the need to remove water by-product from the reaction mixture. An isolated biodiesel yield of 98 ± 2% is achieved using a catalyst loading of 10 wt %, methanol:oil ratio of 12:1, temperature of 90 °C, and reaction time of 6 h. The high activity of our catalyst is attributed to its porous nature and the co-inclusion of reactive SO3H sites and phenolic OH groups. Advantageously, these groups are hydrophilic, allowing the catalyst to remain highly active in the presence of H2O. Nine methyl ester components are identified in the biodiesel product, with 9-octadecanoic acid methyl ester (C18:2, 64.92%) and hexadecanoic acid methyl ester (C16:0, 16.44%) as the major constituents. The catalyst is evaluated over 4 cycles, maintaining a 92 ± 2% isolated yield. Physicochemical analysis of the spent catalyst by SEM-EDX suggests this decrease is due to some loss of mesoporosity and sulfur content.

Magnetite (Fe3O4) nanoparticles coated with dextrose and gluconic acid possessing both super-paramagnetism and excellent optical properties have been productively synthesized through a straightforward, efficient and cost efficient hydrothermal reduction route using Fe3+ as sole metal precursor acquired from accumulated iron ore tailings - a mining waste that usually represents a major environmental threat. Fe3O4/C nanocomposites were fully elucidated by FEGSEM and TEM, revealing a combination of platelets (

Magnetite (Fe

A nanoparticle (NP)-based precatalyst has been developed for organic synthesis: sulfur-modified Au-supported Fe (SAFe). The SAFe was easily prepared through a three-step procedure involving simultaneous in situ metal NP and nanospace organization (PSSO). This method avoids the need for preformed templates for immobilizing and stabilizing the metal nanoparticles. On account of the relative safety and enormous earth abundance of iron, SAFe potentially represents an ideal precatalyst for carbon–carbon bond-forming cross-coupling reactions. As such, it has been applied as a precatalyst to Kumada coupling under ligand-free conditions, proving to be capable of being recycled and used repeatedly for this reaction. Analysis of SAFe and of reaction mixtures suggested that the active species in these reactions are produced in situ by assemblies of iron-based NPs.

Amines in heteroaromatic systems and pharmaceutical intermediates were functionalized through N-methylation with methanol using a palladium-loaded titanium dioxide (Pd/TiO2) photocatalyst. This method provides access to a series of tertiary N-methylamines bearing N-, O-, and/or S-containing heteroaromatic functionalities from primary/secondary amines and methanol under mild reaction conditions. Facile syntheses of several pharmaceuticals containing N-methyl or ethyl groups, as well as related deuterated drugs, was achieved through the late-stage functionalization of amines., ファイル公開：2019-11-05

The design and synthesis of faceted nanoparticles with a controlled composition is of enormous importance to modern catalyst engineering. Faceted FePt-Fe3O4 dumbbell nanoparticles have been prepared by a simple, one-pot technique that avoids the need for expensive additives or preformed seeds. The faceted product consists of an FePt octopod and a cubic Fe3O4 lobe, of mean diameter 13.6 and 14.9 nm, respectively. The mass normalized activity for electrocatalytic oxygen reduction shows that this new structure-type outperforms related catalysts in alkaline media. This work illustrates the power of morphology control and tailoring crystal facet abundance at the nanoparticle surface for enhancing catalytic performance.

Single-source precursors are used to produce nanostructured BiVO4 photoanodes for water oxidation in a straightforward and scalable drop-casting synthetic process. Polyoxometallate precursors, which contain both Bi and V, are produced in a one-step reaction from commercially available starting materials. Simple annealing of the molecular precursor produces nanocrystalline BiVO4 films. The precursor can be designed to incorporate a third metal (Co, Ni, Cu, or Zn), enabling the direct formation of doped BiVO4 films. In particular, the Co- and Zn-doped photoanodes show promise for photoelectrochemical water oxidation, with photocurrent densities >1 mA cm-2 at 1.23 V vs reversible hydrogen electrode (RHE). Using this simple synthetic process, a 300 cm2 Co-BiVO4 photoanode is produced, which generates a photocurrent of up to 67 mA at 1.23 V vs RHE and demonstrates the scalability of this approach.

Single-source precursors are used to produce nanostructured BiVO

Direct functionalization of amino groups in complex organic molecules is one of the most important key technologies in modern organic synthesis, especially in the synthesis of bio-active chemicals and pharmaceuticals. Whereas numerous chemical reactions of amines have been developed to date, a selective, practical method for functionalizing complex amines is still highly demanded. Here we report the first late-stage N-alkylation of pharmaceutically relevant amines with alcohols at ambient temperature. This reaction was achieved by devising a mixed heterogeneous photocatalyst in situ prepared from Cu/TiO

Direct functionalization of amino groups in complex organic molecules is one of the most important key technologies in modern organic synthesis, especially in the synthesis of bio-active chemicals and pharmaceuticals. Whereas numerous chemical reactions of amines have been developed to date, a selective, practical method for functionalizing complex amines is still highly demanded. Here we report the first late-stage N-alkylation of pharmaceutically relevant amines with alcohols at ambient temperature. This reaction was achieved by devising a mixed heterogeneous photocatalyst in situ prepared from Cu/TiO2 and Au/TiO2. The mixed photocatalytic system enabled the rapid N-alkylation of pharmaceutically relevant molecules, the selective mono- and di-alkylation of primary amines, and the non-symmetrical dialkylation of primary amines to hetero-substituted tertiary amines.