A novel iron-catalyzed transfer hydrogenation of alkynes to the corresponding alkenes applying formic acid as a hydrogen donor is reported. An in situ combination of Fe(BF(4))(2)·6H(2)O and tetraphos allows for highly selective hydrogenation of a broad range of aromatic and aliphatic alkynes tolerating different functional groups.

Optically active 1,2-bis(alkylmethylphosphino)ethanes and bis(alkylmethylphosphino)methanes are unique diphosphine ligands combining the simple molecular structure and P-stereogenic asymmetric environment. This work shows that these ligands exhibit excellent enantioselectivity in rhodium-catalyzed asymmetric hydrogenation of , -unsaturated phosphonic acid derivatives. The enantioselective hydro...

The one-step dehydration, decarboxylation and hydrogenation of the bio-based and widely available citric acid is presented. This reaction sequence yields methylsuccinic acid with yields of up to 89%. Optimal balances between the reaction rates of the different steps were found by varying the hydrogenation catalyst and the reaction parameters (H2 pressure, pH, temperature, time and catalyst-to-s...

The hydrogenation of Li3N at low chemical potential has been studied in situ by time-of-flight powder neutron diffraction and the formation of a non-stoichiometric Li4-2xNH phase and Li4NH observed. The results are interpreted in terms of a model for the reaction pathway involving the production of Li4NH and Li2NH, which subsequently react together to form Li4-2xNH. Possible mechanisms for the ...

The Urushibara Ni (U-Ni) hydrogenation catalyst and some modified forms, and for comparison Raney-Ni, were subjected to conventional (oil bath) and MW heating, and subsequently characterized by electron dispersive X-ray analysis (EDX), by BET surface area, and by scanning electron microscopy (SEM); yields of the catalyzed hydrogenation of acetophenone to 1-phenylethanol in 2-propanol by one of ...

The synthesis of (3E)-1-benzyl-3-[(2-oxopyridin-1(2H)-yl)methylidene]piperidine-2,6-dione 5 from N-benzylglutarimide was achieved in three steps. The asymmetric hydrogenation of 4 gave either the product of partial reduction (10) or full reduction (13), depending on the catalyst which was employed, in high ee in each case. Attempts at asymmetric transfer hydrogenation (ATH) of resulted in forma...

In this account, we describe the design, synthesis and applications of tethered versions of the Ru(II)/N-tosyl-1,2-diphenylethylene-1,2-diamine (TsDPEN) class of catalyst that are commonly used for asymmetric transfer hydrogenation and asymmetric hydrogenation of ketones and imines. The review covers key aspects of the reaction mechanisms and examples of applications, including industrial appli...

Among the characteristic features of the coordination chemistry of ruthenium, which are manifested by complexes containing a considerable range of ligands, are the propensities for intraand intermolecular metallation of arenes and for the formation of polyhydride complexes. Some aspects of this coordination chemistry are discussed, including the roles of ruthenium polyhydride complexes in catal...

School of Chemistry, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000, South Africa Email: ‡[email protected]; *[email protected] Carbon nanotubes (CNTs) possess unique properties which make them competitive with conventional catalyst supports. This short review collates fi ndings from many research groups on the benefi ts of palladium/carbon nanotubes in hydrogenat...

The aromatic rings of polystyrene (PS) were hydrogenated in decahydronaphthalene (DHN) expanded with supercritical carbon dioxide (scCO2). Conducting the hydrogenation in scCO2-DHN offers the benefits of improved transport properties, specifically lower solution viscosity and a higher PS diffusion coefficient. Various Pd catalysts are effective for hydrogenating the aromatic rings of PS at temp...