Volume 7 Issue 4, April 2024

Ethylene, despite being a cornerstone of the modern petrochemical industry, continues to pose challenges during its production. Now, a dual single-atom catalyst design emerges as a remarkable solution for the efficient semi-hydrogenation of acetylene.

Gut microbes have enzymes that break down the heavily glycosylated mucin protein of host animals, but known enzymes recognize only one glycan chain. Now, bioinformatic exploration has uncovered a family of mucinases that targets dense sugar residues.

Malonyl-CoA is one of the fundamental building blocks for the synthesis of industrially or pharmaceutically important chemicals, but its biosynthesis via the innate acetyl-CoA carboxylation pathway remains slow and inefficient. Now, an artificial non-carboxylative malonyl-CoA biosynthetic pathway has been developed, significantly enhancing malonyl-CoA supply by boosting carbon and energy efficiency while sidestepping the inhibitions by host cell regulations.

Biomass is a renewable source of carbon that can be exploited to produce valuable chemicals and fuels. This Perspective discusses the electrochemical valorization of biomass, identifying specific chemical transformations in which the approach can excel.

Acetyl-CoA carboxylation is the canonical route for endogenous malonyl-CoA formation in cells. Here, the authors design a non-carboxylative malonyl-CoA pathway independent of acetyl-CoA into multiple microbes for efficient malonyl-CoA-derived natural products biosynthesis.

S-formyl thiols can be produced by S-formylation reactions in enzymatic processes that fix CO₂ through the formate dehydrogenase enzyme. Here the authors show the use of an organocatalytic metal-free process for the direct mono- and di-S-formylation of thiols using CO₂.

Mucins are glycosylated proteins with important biological functions such as protection. Although glycopeptidases can cleave them, dedicated hydrolytic enzymes specific for mucins were unknown. Now microbial mucinases are discovered that specifically recognize mucin O-glycan clusters and employ two glutamic acid residues for catalytic cleavage.

Oxide-derived copper is well-known as a CO₂ reduction electrocatalyst, yet the mechanism of its formation and the structure of the active phase remain unclear. Here the reduction of oxide-derived copper is modelled using large-scale molecular dynamics with a neural network potential, providing important insights into the removal of trapped oxygen under operating conditions.

Electrochemical cross-electrophile coupling with alkyl halides for the construction of C(sp³)–C(sp³) bonds is generally limited to activated alkyl halides. Now this approach is extended to coupling of unactivated alkyl halides using a nickel catalyst under mild conditions.

Nanoparticles are often stabilized by capping ligands but the specific role of such ligands during catalytic processes is often ignored. Now, in situ techniques including spatially resolved infrared nanospectroscopy reveal the ligand-assisted formation of a catalytic microenvironment on the surface of silver nanoparticles with nanoscale precision during CO₂ electroreduction.

Unstrained aryl–aryl bonds are among the most inert bonds in organic chemistry. Now the development of a split cross-coupling strategy enables the direct functionalization of such bonds through Rh-catalysed C–C cleavage and cross-coupling with aryl halides, providing a method for biaryl synthesis.

The synthesis of well-defined heterostructure interfaces can be leveraged to design advanced catalysts. Now a catalyst consisting of carbon-supported Janus particles with crystalline Ru and amorphous CrO_x sides is shown to achieve high performance for both alkaline hydrogen oxidation and evolution reactions due to the synergy between both sides.

The semihydrogenation of acetylene is an important industrial reaction generally targeted with alloy catalysts and more recently with single-atom catalysts. Here, the authors report a MOF-supported Pd₁–Au₁ dimeric system that, by merging such approaches, results in high performance levels under simulated front-end industrial conditions.