Articles in 2023

The direct regioselective oxidation of internal alkenes to ketones poses an important synthetic challenge. Now, directed evolution of a cytochrome P450 enzyme affords a ketone synthase that can efficiently oxidize internal arylalkenes directly to ketones with high chemo- and regioselectivity.

In this Editorial, we provide an overview of the present issue, while introducing some news related to our team.

The chlor-alkali industry is one of the largest global electricity consumers. In the 1970s, the discovery of dimensionally stable anodes (DSAs) allowed for drastic savings in electricity consumption. The fundamental reasons behind the effectiveness of DSAs, however, were only clarified decades later.

The d-band model was proposed by Bjørk Hammer and Jens Nørskov almost 30 years ago to explain trends in the interaction of adsorbates with transition-metal surfaces. It remains a cornerstone in heterogeneous catalysis research and has inspired a wealth of later models.

Scientific research on human insulin was a crucial development in medicine, and its discovery led to the treatment of diabetes, one of the most prevalent global chronic diseases. A seminal work published in 1979 describing recombinant DNA technology to produce human insulin through biocatalysis has resulted in this field’s establishment and routine industrial applications.

The conditions employed for alkane dehydrogenation reactions are usually detrimental for catalyst stability. Now, subnanometre Pt clusters stabilized by the Ge-enriched double four-membered-ring units in a UTL-type zeolite structure show exceptionally high stability for this important transformation.

Linear polyethylene and isotactic polypropylene, the two largest-volume polymers on the market, were invented in the 1950s thanks to diverse mixes of serendipity, intuition and talent. After 70 years, a thoughtful revisitation of those ground-breaking discoveries can still be revealing and inspirational.

Kinetic measurements often involve complex processes, and deconvoluting them to derive active-site chemistry becomes challenging. Now experimental kinetic measurements, density functional theory calculations and microkinetic modelling are combined to provide detailed mechanistic understanding of elementary reactions for ethylene hydrogenation on Pd–Zn γ-brass with isolated active sites.

Ethylene glycol is commercially produced from ethylene under energy-intensive thermocatalytic conditions. Now a cascade electrochemical heterogeneous system can produce ethylene glycol from ethylene or from CO₂ under ambient conditions using electrocatalytically generated H₂O₂ and an integrated catalyst/solid-acid composite.

Hydrogen carriers play an important role in the hydrogen economy. Now, methyl formate is proposed as a suitable chemical hydrogen source for a carbon-neutral hydrogen energy cycle, and faster catalytic hydrogen production rates are achieved compared with those from the widely investigated formic acid and methanol.

Organic semiconductors have potential for application as photocatalysts, but their efficiency is limited by recombination of charge carriers before they can reach the surface. Here hydrogen-bonded organic frameworks with designed micropores decrease the exciton transfer path to improve charge utilization in photocatalytic H₂ evolution.

CO₂ methanation offers a route to synthetic methane production but typically requires high temperatures to achieve sufficient rates. This study presents light-driven CO₂ methanation on an Au/Ce_0.95Ru_0.05O₂ solid-solution catalyst with high CH₄ production rate and selectivity benefiting from synergistic photochemical and photothermal effects.

While hydrosulfenation via addition of sulfenic acid to alkynes was reported decades ago, an asymmetric version of this reaction remained elusive. Now, Ni-catalysed hydrosulfenation of alkynes with in situ-generated sulfenic acids enables the synthesis of chiral alkenyl sulfoxides.

Molecular insights into the mechanism of amide bond formation in the biosynthesis of lincosamide antibiotics remain scarce. Now, the crystal structure of the condensation enzyme CcbD that catalyses this reaction is solved, its substrate scope investigated and a catalytic mechanism proposed.

Supported subnanometric clusters are a much sought-after class of catalyst, but governing the anchoring onto the support and the resulting properties of the clusters remains a challenge. Now the authors show how UTL-type germanosilicate can stabilize ultra-fine Pt clusters, resulting in a superior catalyst for propane dehydrogenation.

Shuttle catalysis is a promising approach to improve traditional hydrofunctionalization reactions, although thermodynamic constraints limit its application. Here the authors show how the properties of zeolites can drive the shuttling equilibrium of such catalytic processes, widening the applicability of reactions such as transfer hydrocyanation and transfer hydroformylation.

Pyridoxal 5′-phosphate (PLP)-dependent enzymes that catalyse Mannich reactions were unknown. Now, it is reported that the PLP-dependent enzyme LolT catalyses a 5-endo-trig Mannich cyclization reaction during the pyrrolizidine core scaffold formation in loline biosynthesis, and its crystal structure is solved.