Volume 2 Issue 3, March 2019

The asymmetric synthesis of chiral γ-lactams is difficult and laborious; typically requiring pre-functionalization of starting materials. Now, a highly efficient alternative approach employing direct C−H amidation via chiral hydrogen-bond-donor catalysts has been developed.

The synthesis of highly branched low molecular weight products — potential synthetic lubricants — directly from ethylene is challenging when highly efficient early transition metal catalysts are employed. Now, an alkane soluble co-catalyst permits the synthesis of such polyethylenes using a zirconium catalyst in a saturated hydrocarbon solvent, where competitive solvent coordination at the active site of the catalyst is relatively unimportant.

The selective electrochemical conversion of ketones to value-added products still represents a challenge, due to a lack of fundamental understanding. Now, a principle has been revealed that allows the steering of the electroreduction of aliphatic ketones on platinum by carefully controlling the coordination number of the platinum atoms.

The hydrogenation of CO₂ to form methane has been known for over a century. However, given increased interest in small-molecule activation for energy storage, and improved catalysts and understanding of the process, it is worthwhile to look again at the reaction. This Perspective discusses recent work on the fundamentals of the Sabatier reaction and also the potential for large-scale applications.

The electrochemical reduction of carbon dioxide to fuels and feedstocks has received increased attention over the past few years. In this Review, Roldan Cuenya and co-workers discuss strategies to achieve high selectivity towards multicarbon products via rational catalyst and electrolyte design.

Samarium iodide is a remarkably useful and mild reductant in organic synthesis, but its use can be problematic due to the need for (super)stoichiometric loadings. Now a method that employs samarium iodide as a catalyst—without the need for a stoichiometric co-reductant—is reported. Loadings as low as 5% are shown to catalyse radical cyclization cascades.

Chiral γ-lactams are of significant interest being present in numerous pharmaceutical agents; however, their chemical synthesis is complex, requiring pre-functionalized starting materials. Now, Park and Chang report an iridium-based catalyst system for the production of chiral γ-lactams from an abundant feedstock via an intramolecular asymmetric sp³ C−H amidation.

Cell viability depends on transcriptional fidelity, but the proofreading mechanism of eukaryotic RNA polymerase II (Pol II) remained elusive. Now, Cheung, Wang, Zhang, Huang and co-workers show that Pol II utilizes the downstream phosphate oxygen of the RNA transcript to activate intrinsic cleavage of misincorporated nucleotides.

Low-molecular-weight, highly branched polyethylenes are attractive candidates for synthetic lubricants, but their efficient production is constrained by a lack of effective catalytic methods. While conventional group IV transition metal catalysts produce diverse polyethylenes on a huge scale, they are unable to produce highly branched polyethylenes. Here a hydrocarbon-soluble organozirconium precatalyst and borate cocatalyst produce the desired polyethylenes with excellent activity and branch selectivity.

The electrocatalytic reduction of carbonyl groups is gaining attention in the context of biorefinery. However, fundamental knowledge on such processes is still limited. Now, the selectivity for the electroreduction of acetone on platinum single crystals is studied, revealing a remarkable structural sensitivity.

The upgrade of carbon monoxide to higher alcohols offers a route to renewable fuels. Now, Sinton, Sargent and co-workers report a highly fragmented, copper-based catalyst with engineered interfaces between the (111) and (100) facets that promote the coupling of C₁ and C₂ species, leading to enhanced production of n-propanol.

Iron single-atom catalysts are among the most promising fuel cell cathode materials in acid electrolyte solution. Now, Shui, Xu and co-workers report concave-shaped Fe–N–C nanoparticles with increased availability of active sites and improved mass transport, meeting the US Department of Energy 2018 target for platinum-group metal-free fuel cell catalysts.

Metal oxides have been identified as a promising class of catalysts for carbon–oxygen bond cleavage in the context of biomass valorization, although the systematic understanding of their reactivity remains elusive. Now, a combination of catalytic screening and first principles calculations provide important insights into this family of catalysts.