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Arguably, water is an ideal hydrogen source for reduction reactions, however with significant difficulties in practice. In this work, water was utilized as a hydrogen source for the electrochemical reduction of benzoic acid esters in an undivided cell by electrolysis with either direct current or rapid alternating polarity current, depending on the electronic properties of the ester. Notably, reactions using D2O afforded valuable d2-benzyl alcohols, with D incorporation rates as high as 97%. Mechanistic studies revealed that the reaction pathway depended on the substrate. [ABSTRACT FROM AUTHOR]

A copper-catalyzed Mannich-type oxidative β-functionalization reaction of amines has been developed. In the presence of an oxidant and a copper catalyst, tertiary amines reacted with N-tosylimines, providing synthetically important 1,3-diamines and enamines, respectively. Preliminary mechanistic studies suggested that the oxidation of the tertiary amine to the enamine intermediate triggers subsequent Mannich-type reactions with N-tosylimines and thus enables the direct β-functionalization of the tertiary amines. [ABSTRACT FROM AUTHOR]

A protocol for nickel-catalyzed hydrocarboxylation of alkynes with formic acid was developed. The protocol allowed for highly efficient synthesis of acrylic acid with a TON of up to 7700. [ABSTRACT FROM AUTHOR]

An iridium complex with a newly prepared chiral spiro amino-phosphine ligand efficiently catalyzed the hydrogenation of both β-aryl-β-methyl-nitroalkenes and β-alkyl-β-methyl-nitroalkenes to the corresponding saturated nitroalkanes, which represents the first report of a chiral catalyst that exhibits high enantioselectivity for the challenging hydrogenation of β,β-dialkyl-nitroalkenes. [ABSTRACT FROM AUTHOR]

Highly efficient iridium catalyzed asymmetric transfer hydrogenation of simple ketones with ethanol as a hydrogen donor has been developed. By using chiral spiro iridium catalysts (S)-1a a series of alkyl aryl ketones were hydrogenated to chiral alcohols with up to 98% ee. [ABSTRACT FROM AUTHOR]

A highly efficient catalytic method for hydrogenation of biomass-derived levulinic acid has been developed and the iridium trihydride complexes of PNP pincer ligands were found to be extremely active catalysts for this transformation, providing γ-valerolactone in high yields with TONs as high as 71 000. [ABSTRACT FROM AUTHOR]

An asymmetric carbenoid insertion into S–H bonds catalyzed by copper–chiral spiro bisoxazoline complexes has been developed, in which a series of α-mercaptoesters were produced in high yields with moderate to good enantioselectivities (up to 85% ee); this result represents the best enantioselectivity in the catalytic asymmetric carbenoid S–H bond insertion reaction. [ABSTRACT FROM AUTHOR]

A new efficient and highly enantioselective direct asymmetric hydrogenation of α-keto acids employing the Ir/SpiroPAP catalyst under mild reaction conditions has been developed. This method might be feasible for the preparation of a series of chiral α-hydroxy acids on a large scale.

Ruthenium-catalyzed highly selective codimerization of N-acetyl α-arylenamines with ethyl acrylates is reported. This codimerization reaction provides a new efficient method for the synthesis of α,β-unsaturated γ-amino esters with a quaternary center.

Modular chiral dendrimers with monodentate phosphoramidite ligands located at the core were synthesized and applied in the Rh-catalyzed asymmetric hydrogenations, afforded unprecedented enhancement of enantioselectivity.

The chiral diphosphinite ligand derived from (R)-1,1'-spirobiindane-7,7'-diol has been found to be highly effective in the Ir-catalyzed asymmetric hydrogenation of quinolines with high substrate/catalyst ratio (up to 5000) and high enantioselectivity (up to 94% ee).

Novel monodentate phosphorus ligands containing the 1,1'-spirobiindane backbone have been synthesized and applied in the asymmetric rhodium-catalyzed hydrogenation of functionalized olefins, providing excellent enantioselectivities (up to 99.3% ee).