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A new method for the generation of benzyl radicals from terminal aromatic alkynes has been developed, which allows the direct cross coupling with acrylate derivatives. Our additive-free protocol employs air-stable diamino Mo3S4 cubane-type cluster catalysts in the presence of hydrogen. A sulfur-centered cluster catalysis mechanism for benzyl radical formation is proposed based on catalytic and stoichiometric experiments. The process starts with the cluster hydrogen activation to form a bis(hydrosulfido) [Mo3(μ3-S)(μ-S)(μ-SH)2Cl3(dmen)3]+ intermediate. The reaction of various aromatic terminal alkynes containing different functionalities with a series of acrylates affords the corresponding Giese-type radical addition products. [ABSTRACT FROM AUTHOR]

The sustainable production of value-added N-heterocycles from available biomass allows to reduce the reliance on fossil resources and creates possibilities for economically and ecologically improved synthesis of fine and bulk chemicals. Herein, we present a unique Ru1CoNP/HAP surface single-atom alloy (SSAA) catalyst, which enables a new type of transformation from the bio-based platform chemical furfural to give N-heterocyclic piperidine. In the presence of NH3 and H2, the desired product is formed under mild conditions with a yield up to 93%. Kinetic studies show that the formation of piperidine proceeds via a series of reaction steps. Initially, in this cascade process, furfural amination to furfurylamine takes place, followed by hydrogenation to tetrahydrofurfurylamine (THFAM) and then ring rearrangement to piperidine. DFT calculations suggest that the Ru1CoNP SSAA structure facilitates the direct ring opening of THFAM resulting in 5-amino-1-pentanol which is quickly converted to piperidine. The value of the presented catalytic strategy is highlighted by the synthesis of an actual drug, alkylated piperidines, and pyridine. The synthesis of nitrogen-containing heterocycles from biomass is scarcely known. Here, the authors report a strategy for the N-heterocyclic piperidines synthesis by one-pot amination of the bio-based furfural utilizing a Ru1CoNP/HAP surface single-atom alloy catalyst. [ABSTRACT FROM AUTHOR]

Deuterated organic molecules are of interest for many applications ranging from mechanistic investigations in basic organic and physical chemistry to the development of new pharmaceuticals. Thus, methodologies for isotope-labelling reactions continue to be important. Here, a convenient methodology for hydrogen/deuterium exchange reactions in electron-rich arenes is reported using simple iron salts and deuterium oxide as isotope source. [ABSTRACT FROM AUTHOR]

Manganese‐catalyzed hydrogenation reactions have aroused widespread interest in recent years. Among the catalytic systems described, especially PNP‐ and NNP–Mn pincer catalysts have been reported for the hydrogenation of aldehydes, ketones, nitriles, aldimines and esters. Furthermore, NNP−Mn pincer compounds are efficient catalysts for the hydrogenolysis of less reactive amides, ureas, carbonates, and carbamates. Herein, the synthesis and application of specific imidazolylaminophosphine ligands and the corresponding Mn pincer complexes are described. These new catalysts have been characterized and studied by a combination of experimental and theoretical investigations, and their catalytic activities have been tested in several hydrogenation reactions with good to excellent performance. Especially, the reduction of N‐heterocycles can be performed under very mild conditions. [ABSTRACT FROM AUTHOR]

Heterogeneous catalysis, hydrodehalogenation, nickel, reduction, supported catalysts Keywords: heterogeneous catalysis; hydrodehalogenation; nickel; reduction; supported catalysts EN heterogeneous catalysis hydrodehalogenation nickel reduction supported catalysts 1 1 1 03/11/22 20220308 NES 220308 B The Front Cover b shows how the "Dehalogenato" spell allows to replace halogen atoms by hydrogens, using a heterogeneous nickel catalyst supported on titanium oxide in the presence of dihydrogen. [Extracted from the article]

A new method for the generation of benzyl radicals from terminal aromatic alkynes has been developed, which allows the direct cross coupling with acrylate derivatives. Our additive-free protocol employs air-stable diamino Mo 3 S 4 cubane-type cluster catalysts in the presence of hydrogen. A sulfur-centered cluster catalysis mechanism for benzyl radical formation is proposed based on catalytic and stoichiometric experiments. The process starts with the cluster hydrogen activation to form a bis(hydrosulfido) [Mo 3 (μ 3 -S)(μ-S)(μ-SH) 2 Cl 3 (dmen) 3 ] +  intermediate. The reaction of various aromatic terminal alkynes containing different functionalities with a series of acrylates affords the corresponding Giese-type radical addition products.

The use of bis(NHC) manganese(I) complexes 3 as catalysts for the hydrogenation of esters was investigated. For that purpose, a series of complexes has been synthesized via an improved two step procedure utilizing bis(NHC)-BEt 3 adducts. By applying complexes 3 with KHBEt 3 as additive, various aromatic and aliphatic esters were hydrogenated successfully at mild temperatures and low catalyst loadings, highlighting the efficiency of the novel catalytic system. The versatility of the developed catalytic system was further demonstrated by the hydrogenation of other substrate classes like ketones, nitriles, N-heteroarenes and alkenes. Mechanistic experiments and DFT calculations indicate an inner sphere mechanism with the loss of one CO ligand and reveal the role of BEt 3 as cocatalyst., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Manganese-catalyzed hydrogenation reactions have aroused widespread interest in recent years. Among the catalytic systems described, especially PNP- and NNP-Mn pincer catalysts have been reported for the hydrogenation of aldehydes, ketones, nitriles, aldimines and esters. Furthermore, NNP-Mn pincer compounds are efficient catalysts for the hydrogenolysis of less reactive amides, ureas, carbonates, and carbamates. Herein, the synthesis and application of specific imidazolylaminophosphine ligands and the corresponding Mn pincer complexes are described. These new catalysts have been characterized and studied by a combination of experimental and theoretical investigations, and their catalytic activities have been tested in several hydrogenation reactions with good to excellent performance. Especially, the reduction of N-heterocycles can be performed under very mild conditions., (© 2022 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

A phosphine-oxide-promoted, cobalt-catalysed reductive etherification using syngas as a reductant is reported. This novel methodology was successfully used to prepare a broad range of unsymmetrical ethers from various aldehydes and alcohols containing diverse functional groups, and was scaled-up to multigram scale under comparably mild conditions. Mechanistic experiments support an acetalization-hydrogenation sequence., (© 2022 Wiley-VCH GmbH.)