Reviews & Analysis

Two-dimensional polymers, which exhibit periodic bonding in two orthogonal directions, offer mechanical, electronic and structural properties distinct from their linear or irregularly crosslinked polymer counterparts. Their potential is largely unexplored because versatile and controlled synthetic strategies are only now emerging. This Review describes recent developments in two-dimensional polymerization methods.

A complex featuring a uranium(VI) terminal nitride functional group has been isolated through mild oxidation, and shown to be highly reactive. Under photolysis, it converts into a compound that is capable of C–H bond activation.

Designing a molecule that acts as both an initiator for a photo-controlled radical polymerization and as a reactive end-group for polymer chain crosslinking has enabled the preparation of polymeric gels whose properties can be controlled by exposure to sunlight.

Four-dimensional electron microscopy has been applied to the detailed characterization of metal–organic-framework nanoparticles undergoing an electronic transition. The transition characteristics of a single particle were found to differ from those of an ensemble, and also to vary from one nanoparticle to the next.

The electrolysis of water provides a link between electrical energy and hydrogen, a high-energy-density fuel and a versatile energy carrier, but the process is expensive. Splitting the electrolysis reaction into two steps through an electrochemical 'buffer' offers a new way to think about improving the cost and efficiency of electrolysers.

Non-enzymatic copying of an RNA template is appealing as a transition from pre-life to an RNA world, but it has been difficult to demonstrate in the laboratory. Now, two separate studies focusing on RNA's backbone connectivity offer partial solutions to some of the problems raised with this hypothesis for the origin of life.

Over the past decade, C–H bond activation has progressively become a well-established synthetic tool. An increased scope and understanding of this transformation has seen it being used in a wide range of contexts, not only in traditional organic synthesis, but also in late-stage diversification strategies for organic materials and biologically active molecules.

Tying molecules together in a link results in tremendous stabilization of the radical species they can form. Six clearly distinguishable charged states — which can be interconverted reversibly — have now been observed in a densely cationic system.

During photosynthesis, the oxygen-evolving complex oxidizes water to produce molecular oxygen. Now, a possible role for the calcium ion in this complex has been proposed based on the electrochemical properties of a series of synthetic heterometallic clusters.

The study of the reaction of a ground-state O atom with H₂ has previously proved difficult because of its high activation barrier. Now, new experiments have revealed unexpected OH product states; but perhaps there is a simple explanation?

Combined spectroscopic measurements and theoretical calculations bring to light an ultrafast excited-state deactivation process in peptides that may contribute to the ultraviolet photostability of proteins.

Strategies for making sequence-controlled polymers in the laboratory are really quite primitive in comparison with those used in nature. By combining concepts from natural systems and synthetic polymer chemistry, it has now been shown that DNA codes can be translated into non-nucleic-acid polymers with defined sequences.

Hydrogen–oxygen alkaline fuel cells are promising devices for the 'hydrogen economy' but their oxidation of hydrogen fuel is slow compared with that of acidic fuel cells. More efficient electrocatalysts have now been prepared in which the adsorption of hydroxyl groups onto the electrode surface is controlled through suitable promoters.

A small molecule that mimics the sequence-specific peptide synthesis of nature's ribosomes paves the way for more elaborate artificial molecular synthesizers.

Two-dimensional materials have recently garnered much interest in the scientific and technology communities. This Review describes how ultrathin transition metal dichalcogenides combine tunable structure and electronic properties, achieved through altering their composition, with versatile chemistry. This makes them attractive in various fields, for example as lithium-ion battery electrodes and electrocatalysts for the hydrogen evolution reaction.

Metallic nanoparticles enable the control of optical fields at the nanometre scale, enhancing the absorption and emission of local emitters. Now, using the self-assembling properties of DNA, functional nanoantennas have been developed that comprise a versatile and robust assembly of gold nanoparticles and emitters.

Overcoming drug resistance requires drug–protein interactions that persist in spite of mutations, but such interactions are difficult to characterize. Two-dimensional infrared spectroscopy can reveal the dynamics of how key molecular groups interact, allowing new insights into how some drugs overcome resistance.

A synthetic strategy that uses a series of simple reactions to distort the core architecture of complex natural products could provide libraries of stereochemically rich compounds that will help in the search for new biological probes and drugs.

Many of us eat mushrooms, but few of us have probably ever thought about — let alone witnessed — the epic battle of kingdoms that can occur between this delicacy and its bacterial pathogens. Now, imaging mass spectrometry has enabled the identification of a bacterium's potent antifungal weapon of choice.

The direct observation and quantification of G-quadruplex structures formed from DNA in human cells during the cell cycle demonstrate the biological importance of these structures and point towards opportunities for targeting them with small-molecule drugs.