Catalytic hydrogenation under mild conditions of olefins, unsaturated aldeydes and ketones, nitriles and nitroarenes was investigated, using a supported rhodium complex obtained by copolymerization of Rh(cod)(aaema) [cod: 1,5-cyclooctadiene, aaema-: deprotonated form of 2-(acetoacetoxy)ethyl methacrylate] with acrylamides. In particular, the hydrogenation reaction of halonitroarenes was carried...

A library of 20 monodentate phosphoramidite ligands has been prepared and applied in rhodium-catalyzed asymmetric hydrogenation. This resulted in the identification of two ligands, PipPhos and MorfPhos, that afford excellent and in several cases unprecedented enantioselectivities in the hydrogenation of N-acyldehydroamino acid esters, dimethyl itaconate, acyclic N-acylenamides, and cyclic N-acy...

Reactions of a-amino acids with ketones under hydrogenation conditions using 20% Pd(OH)2/C as the catalyst gave N-mono-alkylated amino acids in high yields. Reductive methylation of N-mono-alkylated amino acids under the same hydrogenation conditions at 50°C afforded N,N-di-alkylated amino acids in excellent yields. This simple method has been used to synthesize N-monoand N,N-di-alkylated amino...

Little attention has been given to the use of ruthenium and osmium as catalysts for vapour-phase reactions. This paper shows that both these metals when supported on alumina possess signijcant activity for the hydrogenation of unsaturated hydrocarbons. In the hydrogenation of butene, butadiene and acetylene their activity is comparable with that shown by the other platinum group metals, althoug...

Employment of a Pd/C-pyridine combination as a catalyst is a very useful method for the selective removal (hydrogenolysis) of phenolic O-benzyl, N-Cbz and benzyl ester protective groups and for the selective hydrogenation of nitro and olefin functions of phenol derivatives protected with the MPM group. These discriminatory results are apparently attributable to the effect of pyridine. The MPM g...

A homogeneous catalyst system for the asymmetric cis-hydrogenation of 2,5-disubstituted furans leading to 2',3'-dideoxynucleoside analogues is described. Best enantioselectivities (ee values of up to 72%) were obtained with cationic rhodium complexes ligated by diphospholanes of the butiphane family. The selectivity of the hydrogenation was reversed by the addition of a base or a polar protic s...

The enantioselective hydrogenation of 2-benzylquinolines and 2-functionalized and 2,3-disubstituted quinolines was developed by using the [Ir(COD)Cl](2)/bisphosphine/I(2) system with up to 96% ee. Moreover, mechanistic studies revealed the hydrogenation mechanism of quinoline involves a 1,4-hydride addition, isomerization, and 1,2-hydride addition, and the catalytic active species may be a Ir(I...

Hydrogenation reactions can be used to store energy in chemical bonds, and if these reactions are reversible, that energy can be released on demand. Some of the most effective transition metal catalysts for CO2 hydrogenation have featured pyridin-2-ol-based ligands (e.g., 6,6'-dihydroxybipyridine (6,6'-dhbp)) for both their proton-responsive features and for metal-ligand bifunctional catalysis....

Introduction During catalytic hydrogenation of vegetable oils, some of the naturally occurring cis double bonds are isomerized to trans fatty acids (TFA). High levels of trans fats in the diet are linked to higher occurrence of coronary health diseases [1]. However, all trans fatty acids are not harmful, some conjugated linoleic acid (CLA) isomers are reported to have anticarcinogenic, -atherog...

Graphitic carbon nitride nanosheets were investigated for developing effective Pt catalyst supports for selective hydrogenation of furfural to furfuryl alcohol in water. The nanosheets with an average thickness of about 3 nm were synthesized by a simple and green method through thermal oxidation etching of bulk g-C3N4 in air. Combined with the unique feature of nitrogen richness and locally con...