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Iron-Catalyzed Cyclization of Nitrones with Geminal-Substituted Vinyl Acetates: A Direct [4 + 2] Assembly Strategy Leading to 2,4-Disubstituted Quinolines
Enantioselective Cu-Catalyzed Arylation of Secondary Phosphine Oxides with Diaryliodonium Salts toward the Synthesis of P-Chiral Phosphines
Practical Synthesis of Amides via Copper/ABNO-Catalyzed Aerobic Oxidative Coupling of Alcohols and Amines
[Report] Palladium-tin catalysts for the direct synthesis of H2O2 with high selectivity
A Further Decrease in the Catalyst Loading for the Palladium-Catalyzed Direct Intramolecular Arylation of Amides and Sulfonamides
Abstract
The direct arylation of N-substituted o-bromobenzanilides and benzenesulfonamides via CH bond functionalization has been developed using very low catalyst loadings. This novel cost-effective and more sustainable method relies on a PCN-type palladium pincer complex as a highly active palladium source, providing a general and efficient access to phenanthridinones, biaryl sultams and related heterocyclic systems. The beneficial effect of water as cosolvent has been observed in this process, which is not seriously influenced by electronic effects at the arene moieties or sterically demanding substituents at the amide or sulfonamide nitrogen. In addition, a number of experiments (kinetic plot, poisoning assays, TEM, ESI) have been performed in order to understand the role of the employed palladium complex in this reaction.
Rhodium-Catalyzed C–H Activation of Phenacyl Ammonium Salts Assisted by an Oxidizing C–N Bond: A Combination of Experimental and Theoretical Studies
Coating Polycyclic Aromatic Hydrocarbon Cations with Helium Clusters: Snowballs and Slush
Spatial control of functional properties via octahedral modulations in complex oxide superlattices
Article
Structural properties have been a key factor that controls the electronic and magnetic behaviour at the interface of two oxide materials. Here the authors achieve a spatial control over these functional properties in oxides through the formation of octahedral superstructures in manganite superlattices.
Nature Communications doi: 10.1038/ncomms6710
Authors: E. J. Moon, R. Colby, Q. Wang, E. Karapetrova, C. M. Schlepütz, M. R. Fitzsimmons, S. J. May
Hierarchically Organized Silica–Titania Monoliths Prepared under Purely Aqueous Conditions
Abstract
Hierarchically organized silica–titania monoliths were synthesized under purely aqueous conditions by applying a new ethylene glycol-modified single-source precursor, such as 3-[3-{tris(2-hydroxyethoxy)silyl}propyl]acetylacetone coordinated to a titanium center. The influence of the silicon- and titanium-containing single-source precursor, the novel glycolated organofunctional silane, and the addition of tetrakis(2-hydroxyethyl)orthosilicate on the formation of the final porous network was investigated by SEM, TEM, nitrogen sorption, and SAXS/WAXS. In situ SAXS measurements were performed to obtain insight into the development of the mesoporous network during sol–gel transition. IR-ATR, UV/Vis, XPS, and XAFS measurements showed that up to a Si/Ti ratio of 35:1, well-dispersed titanium centers in a macro-/mesoporous SiO2 network with a specific surface area of up to 582 m2 g−1 were obtained. An increase in Ti content resulted in a decrease in specific surface area and a loss of the cellular character of the macroporous network. With a 1:1 Si/Ti ratio, silica–titania powders with circa 100 m2 g−1 and anatase domains within the SiO2 matrix were obtained.
Hierarchically organized SiO2/TiO2 monoliths were synthesized in purely aqueous conditions by applying an ethylene glycol modified single-source precursor (SSP), such as 3-[3-{tris(2-hydroxyethoxy)silyl}propyl]acetylacetonate coordinated to a titanium center. The influence of the SSP on the formation of the final porous network was investigated. The homogeneity of the Si and Ti centers in the oxide matrix was also investigated.
Reversible carbon-carbon bond formation between carbonyl compounds and a ruthenium pincer complex
DOI: 10.1039/C3CC43517B, Communication
This communication describes the reversible reaction of a ruthenium pincer complex with a variety of carbonyl compounds.
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[Report] Direct Evidence of a Dinuclear Copper Intermediate in Cu(I)-Catalyzed Azide-Alkyne Cycloadditions
Authors: B. T. Worrell, J. A. Malik, V. V. Fokin