Articles in 2018

Despite the many recent developments in iron-catalysed cross-couplings, the mechanistic understanding of these reactions is lacking compared to the more studied palladium and nickel variants. Here, the authors find that during iron-catalysed Negishi reactions the diphosphine ligand predominately binds to the zinc—rather than the iron—centre.

Carbon-based single-atom catalysts usually rely on nitrogen co-doping to stabilize the single metal atoms as metal–N₄ moieties. Now, Wei, Yao and colleagues make use of operando techniques to show that under alkaline hydrogen evolution reaction conditions the Co–N₄ active site undergoes structural distortion to a HO–Co–N₂ configuration.

Silicon–hydride materials are attractive candidates for the photoreduction of carbon dioxide into fuels, although they have only worked stoichiometrically so far. Now, Ozin and co-workers show how decorating silicon nanosheets with palladium nanoparticles renders the process catalytic.

Single-atom catalysts are receiving much attention, but insights into their active sites or the differences in reactivity with conventional nanoparticles are still controversial. Now, operando studies on CO oxidation with Ir/MgAl₂O₄ accompanied by computational investigations reveal important features of this class of catalyst.

The use of electrochemistry in asymmetric catalysis can prove challenging, not least due to the difficulty of achieving chemo- and stereoselectivity in combination with very reactive electrochemically generated intermediates. Here, catalytic asymmetric electrosynthesis is reported for the synthesis of 1,4-dicarbonyl compounds with high enantiomeric excess, including compounds with all-carbon quaternary stereocentres. The chiral-at-metal catalyst activates the substrate towards anodic oxidation in addition to controlling the enantioselectivity of the process.

Reusable catalysts based on earth-abundant metals could offer inexpensive and sustainable routes in organic synthesis. Here a nickel catalyst—formed by pyrolysis of a nickel complex on a γ-Al₂O₃ support—is shown to be highly active for synthesis of primary amines via reductive amination. The catalyst operates with aqueous ammonia and either aldehydes or ketones, tolerating a wide range of functional groups.

The electroreduction of carbon dioxide to formate represents a desirable strategy for the production of fuels and commodity chemicals. Now, guided by density functional theory, Cui and colleagues report CuSn₃ alloys that exhibit high activity and selectivity for formate production from CO₂ electroreduction at potentials as low as −0.5 V versus RHE.

Copper-based catalysts, especially the so-called oxide-derived copper, are capable of producing multicarbon species from electrochemical CO₂ reduction. However, little is known about their active sites despite intensive research efforts. Now, Lum and Ager show that oxide-derived copper catalysts have three distinct product-specific sites for the formation of C₂₊ chemicals, unlike polycrystalline copper or (111)- and (100)-oriented copper films which show no evidence of product specific sites.

Nanoscale texture of electrocatalysts, enabled by the tools of nanoscience, is emerging as an important lever for the control of electrochemical reaction pathways.

A crucial malonic acid moiety in the antibiotic malonomycin has been shown to be installed by a bacterial vitamin K-dependent (VKD) carboxylase orthologue.

The biosynthesis of the pharmacophoric tetrahydropyran of the clinically important antibiotic mupirocin remained enigmatic for a long time. Now, research shows that this ring is formed by a unique epoxidation–epoxide-opening cascade starting from a non-activated alkane.

Single-atom catalysts recently attracted considerable research interest for heterogeneous electrocatalysis, including the oxygen reduction reaction. Now, an intriguing two-step approach towards a less explored atomic nitrogen-coordinated manganese with a high loading density has been developed.

Single-atom catalysts are very attractive due to their ability to maintain high activities at the lowest possible precious metal loading. Here, a double transition metal MXene that effectively anchors single Pt atoms is reported, and exhibits superior performance and stability towards the hydrogen evolution reaction.

Predicting highly enantioselective ligands for a given asymmetric catalytic reaction is very challenging, but could greatly reduce the need for high-throughput, trial-and-error experimentation. Here, the authors report a freely available, automated tool to identify appropriate chiral ligands for given substrates in asymmetric catalysis.

Unlike the more common C–H functionalization, methods for the functionalization of C–C bonds are scarce. Here, Ackermann and co-workers show that an inexpensive manganese catalyst is capable of selectively activating C–C bonds for alkylations, alkenylations, and allylations in water.

Catalysts are dynamic species, whose structure can change over the course of a reaction. Here, structural changes are mapped for cobalt–palladium nanoparticles during CO oxidation, showing a reconstruction to CoO_x on palladium surfaces. Furthermore, the composition-dependent reconstruction can be correlated with the trend in catalytic activity.