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Cerium and boron are commonly used components to tune the acidic/basic property of catalysts in industry. In this work, cerium or boron‐doped copper‐based catalysts (xM−Cu/SiO2, M=Ce/B) were prepared with the ammonia‐evaporation method. Both X‐ray diffraction and Auger electron spectroscopy revealed that Cu+ content increased along with the Ce‐doping, but decreased by B‐doping. NH3‐Temperature Program Desorption results showed no change in the acidity of Ce‐doped catalysts, while significant amounts of medium‐strong acid sites appeared after B‐doping. Application in ethylene carbonate hydrogenation indicates the promoting role of Ce‐dopant in methanol production, while boron exhibits negative effects. The significant difference can be attributed to distinctive acidic/basic properties of Ce/B dopants, which affect the interaction between Cu and Si in the precursors, and thus adjust the ratio of Cu+/(Cu++Cu0). [ABSTRACT FROM AUTHOR]

An efficient two‐step synthesis for the conversion of biomass‐derived 5‐hydroxymethyl‐furfural (HMF) to a variety of N‐substituted 2‐hydroxymethyl‐5‐methylpyrroles was developed. In the first step, 1‐hydroxyhexane‐2,5‐dione (HHD) was obtained by hydrogenation of HMF and thereafter used in a Paal–Knorr reaction with a range of amines in the absence of catalyst at room temperature. The reaction could potentially be used as a click reaction. [ABSTRACT FROM AUTHOR]

Abstract: An efficient strategy for the conversion of biomass derived 5‐hydroxymethylfurfural (HMF) into 2‐hydroxy‐3‐methylcyclopent‐2‐enone (MCP) by an intramolecular aldol condensation of 1‐hydroxyhexane‐2,5‐dione (HHD) has been developed. Further transformations of MCP towards the diol, enol acetate, levulinic acid and N‐heterocyclic compounds are also reported. [ABSTRACT FROM AUTHOR]

The 'green' reduction of carboxylic acids to alcohols is a challenging task in organic chemistry. Herein, we describe a general protocol for generation of alcohols by catalytic hydrogenation of carboxylic acids. Key to success is the use of a combination of Ru(acac)3, triphos and Lewis acids. The novel method showed broad substrate tolerance and a variety of aliphatic carboxylic acids including biomass-derived compounds can be smoothly reduced. [ABSTRACT FROM AUTHOR]

Ethers are of fundamental importance in organic chemistry and they are an integral part of valuable flavors, fragrances, and numerous bioactive compounds. In general, the reduction of esters constitutes the most straightforward preparation of ethers. Unfortunately, this transformation requires large amounts of metal hydrides. Presented herein is a bifunctional catalyst system, consisting of Ru/phosphine complex and aluminum triflate, which allows selective synthesis of ethers by hydrogenation of esters or carboxylic acids. Different lactones were reduced in good yields to the desired products. Even challenging aromatic and aliphatic esters were reduced to the desired products. Notably, the in situ formed catalyst can be reused several times without any significant loss of activity. [ABSTRACT FROM AUTHOR]

Zwei Eisenspezies im Team: Ein NAD(P)H ‐ Modell wird in einer eisenkatalysierten Reduktion mit molekularem Wasserstoff in situ regeneriert. Die anschließende biomimetische Reduktion von α ‐ Keto ‐ und α ‐ Iminoestern liefert in Gegenwart einer Eisen ‐ basierten Lewis ‐ Base (LA) α ‐ Hydroxy ‐ bzw. α ‐ Aminosäureester in guten bis exzellenten Ausbeuten (siehe Schema; NAD(P)+=Nicotinamidadenindinucleotid(phosphat), TM=Übergangsmetall). [ABSTRACT FROM AUTHOR]

On the way to a green carbon cycle: Ding and co‐workers developed the highly efficient catalyst 1 for the hydrogenation of cyclic carbonates to diols and methanol (TON up to 87 000) by modification of the industrially applied omega process. [ABSTRACT FROM AUTHOR]

The title reaction proceeds successfully with the simple catalyst Rh(cod)(acac) which reveals an excellent chemoselectivity in the presence of various sensitive functional groups. [ABSTRACT FROM AUTHOR]

Aryl, benzyl, and alkylcarboxylic acids endowed with a range of functional groups as well as dicarboxylic acids are efficiently reduced to the corresponding alcohols. [ABSTRACT FROM AUTHOR]

A molecular diagram is presented of Lewis acid induced ruthenium(II)-catalyzed etherifications by carboxylic acids or esters' selective hydrogenation.

An abstract of the article "Relay Iron/Chiral Broensted Acid Catalysis: Enantioselective Hydrogenation of Benzoxazinones" by L.-Q. Lu and colleagues is presented.

A general method for the hydrogenative deoxygenation of tertiary, secondary, and primary amides into the corresponding amines is developed. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "A General Catalytic Methylation of Amines Using Carbon Dioxide" by Y. Li and colleagues, published in the periodical "Angewandte Chemie International Edition" in 2013.

This method uses dual iron catalysis for the title reaction. [ABSTRACT FROM AUTHOR]