News & Views in 2022

Amino-containing four-carbon threose nucleic acids (TNAs) have long been considered to be prebiotically irrelevant due to their difficult formation. Now, a prebiotically plausible route to 3′-amino-TNA nucleoside triphosphate has been developed, raising the possibility of 3′-amino-TNA as a non-canonical nucleic acid during the origin of life.

This year marks the 50th anniversary of Baird’s rules of aromaticity — a set of perturbational molecular orbital theory analyses that has garnered considerable attention in the past ten years in light of its many real-world applications in photochemistry.

Over the past 25 years, the photo-induced spin-crossover behaviour of Fe(II) complexes has puzzled scientists. Now, a symmetry-breaking twisting mode has been observed during the relaxation of such a complex. Controlling its configuration using enantiopure counterions has also been shown to slow down the relaxation.

Antibody-mediated delivery of therapeutics has been primarily limited to agents containing amine, alcohol or thiol functional groups. Now, an approach has been developed to create stable and bio-reversible prodrugs that mask ortho-quinones. Drug release requires both protease activation followed by acid-assisted elimination.

Trisubstituted macrocyclic alkenes are prominent moieties in natural products, and although ring-closing metathesis reactions can be used to access such targets, the yields are typically suboptimal and the stereochemical outcome is unpredictable. Now, a methodology has been developed that tackles both of these challenges.

Explaining the controlled emergence and growth of molecular complexity at life’s origins is one of prebiotic chemistry’s grand challenges. Now, it has been shown that we can observe how the self-organization of a complex carbohydrate network can be modulated by its environment.

Being able to run two reactions concurrently enables synthetic methods to be streamlined, but simultaneously controlling the selectivity of both reactions is an enormous challenge. Now, a directing group is used to reinvent a classic tandem reaction, activating specific sp³ C–H bonds with pinpoint accuracy.

The rational synthesis of organic nanotubes and their hierarchical architectures has remained challenging. Now, one-dimensional hollow covalent organic frameworks have been prepared that can further assemble into toroid-shaped materials.

Understanding how surface structure affects catalyst selectivity is limited by the ability to synthesize atomically precise active-site ensembles. Now, by using intermetallic Pd–Zn, a series of well-defined multinuclear Pd–metal–Pd catalytic sites have been generated and studied, providing insights into their selectivity for the semi-hydrogenation of acetylene.

Molecular photocatalysts for generating solar fuels such as hydrogen degrade over time, ceasing to function as intended. Now the mechanism by which a ruthenium–platinum-based hydrogen-evolving photocatalyst breaks down has been identified, leading to the development of a repair strategy that uses singlet oxygen to regenerate an inactivated bridging ligand.

Extending mass spectrometry measurements of biomolecules into the megadalton regime is challenging due to the limited resolving power of currently used mass analysers. Now, using single ion-charge detection Orbitrap mass spectrometry, a mass accuracy of 0.001% has been demonstrated for protein particles larger than 9 MDa.

Electron spin relaxation, important in quantum information science, can be slowed down at clock transitions — which are insensitive to magnetic noise. It has now been shown that such transitions can be tuned, to high frequency, in rare-earth coordination complexes through control of s- and d-orbital mixing.

Many of the methods used to make phosphines proceed via phosphorus trichloride-based intermediates, leading to chloride waste that is difficult to recycle. It has now been shown that this disadvantage can be overcome by using a method that directly converts white phosphorus into value-added phosphorus compounds.

Plastics that are developed from renewable resources and can be recycled are highly environmentally desirable alternatives to current petroleum-based non-degradable polymers. Now, an effective and robust industrially relevant strategy towards high-performance biomass-derived degradable poly(γ-thiobutyrolactone)s has been developed.

The electronic structure of an electrode can affect the electron transfer rate of electrochemical processes at its surface. Now, it has been shown that varying the ‘twist’ angle between two stacked layers of graphene modifies the bilayer electronic structure and provides a new dimension to control interfacial redox activity.

Peptides are a class of versatile biomolecules that function as hormones, signalling messengers and drugs. Now, two papers report alternative approaches to tailor their chemical properties, which enables the transport of biomacromolecules into cells. These approaches could find use in a wide range of biomedical applications.

The emergence of protometabolic reactions that evolved into today’s metabolic pathways is unclear. Now, evidence suggests that the chemical origin of biological carbon metabolism may have relied on the versatility of a single primitive C₁ feedstock molecule — hydrogen cyanide.

The adsorption of molecules onto a surface from solution generally proceeds spontaneously by means of an equilibrium process. Now, it has been shown that macrocycles can be pumped onto a MOF substrate through the formation of mechanical bonds in a ratcheting mechanism that results in an out-of-equilibrium state.

Despite the disordered and dynamic environment in which it occurs, photosynthetic light harvesting is highly efficient. Now, measurements of energy transfer in single photosynthetic antennae show how these structures deal with protein fluctuations, robustly transferring the energy before it is lost.

Combining computational design with directed evolution has the potential to deliver enzymes with new functions, yet so far de novo catalysts have been limited to a handful of model transformations. Now, a primitive computationally designed enzyme has been remodelled into an efficient enantioselective catalyst for the Morita–Baylis–Hillman reaction.