Research articles

A supramolecular system has been assembled that moves autonomously in the presence of a molecular fuel. Platinum nanoparticles entrapped in a polymer stomatocyte — a bowl-shaped polymer vesicle — catalyse the decomposition of the molecular fuel, hydrogen peroxide. The resulting generation of water and oxygen induces a directional movement of the stomatocyte.

The oxo groups in the common trans-uranyl ion — present in the majority of known uranium compounds — are linear and inert. Now, a new reduced binuclear uranium–dioxo compound with very strong metal coupling and remarkable air stability has been formed through oxo migration and silylation.

To achieve chemoselective additions of organometallics to carbonyls, it is important to consider the combination of acylating agent and organometallic as a reactive pair rather than either one in isolation. Here, a chemoselective, controlled and general methodology for the conversion of secondary amides to ketones and ketimines is described.

Surfactant-capped nanoparticles of various sizes, shapes and compositions have been completely enshrouded within a metal–organic framework in a controlled, well-dispersed manner. The resulting hybrid materials exhibit active properties — catalytic, magnetic and optical — arising from the nanoparticles as well as sieving and orientation effects originating from the porous framework.

Graphene oxide produced via the standard Hummers method possesses a high degree of chemical inhomogeneity and limited reversibility. Now, it has been shown that an alternative ultra-high-vacuum approach for oxidizing epitaxial graphene yields uniform epoxy functionalization with thermal reversibility at temperatures as low as 260 °C.

It is shown here that the proper combination of physical forces can induce chirality during the self-assembly of achiral molecules. Rotation and effective gravity created by high magnetic fields during the nucleation phase, together with the magnetic alignment of the nanoaggregates initially formed, control the enantioselectivity of porphyrin assemblies.

An isolable diamidocarbene is shown to participate in reversible [2+1] cycloadditions with a variety of both electron-deficient and electron-rich olefins and aldehydes. Subsequent hydrolysis of a N,N′-diamidocyclopropane derived from styrene afforded the corresponding linear carboxylic acid, effectively establishing a metal- and carbon monoxide-free, anti-Markovnikov olefin hydrocarboxylation reaction.

A two-dimensional polymer with internal periodicity has now been constructed. The procedure involves the rational molecular design of monomers, which first crystallize into a laminar lattice. A photo-induced polymerization then occurs laterally within each layer, and the resulting polymer crystals are subsequently delaminated into individual, free-standing two-dimensional polymers.

The site-specific incorporation of a norbornene amino acid into proteins via genetic code expansion, together with the synthesis of a series of tetrazine-based probes that exhibit turn-on fluorescence on their fast cycloaddition with norbornene, enables rapid protein labelling on mammalian cells.

The bonding order of multiply bonded main-group elements is conventionally thought to be limited to triple bonds. Now, using high-level theoretical methods, it is shown that C₂ and its isoelectronic molecules CN⁺, BN and CB⁻ are quadruply bonded, featuring not only one σ - and two π-bonds, but also one weak ‘inverted’ bond.

Solving the structure of zeolites is often challenging because of their small particle size. Now, electron crystallography reveals the structure of a family of complex intergrown zeolite materials. These zeolites contain unique pair-wise 12-ring channels that intersect with 10-ring channels, and are promising catalysts for converting gasoline into diesel fuel.

Drug-likeness is a key consideration when selecting compounds during the early stages of drug discovery, but its evaluation in absolute terms does not adequately reflect the spectrum of compound quality. Here, an intuitive and transparent quantitative measure of drug-likeness is proposed that attempts to capture the abstract notion of aesthetics in medicinal chemistry.

Mixed-metal oxide catalysts oxidize hydrocarbons into CO and CO₂ through surface oxygen species that have yet to form lattice oxide ions. The one-step oxidation of decane into a range of oxygenated aromatics by a fully oxidized iron molybdate catalyst has now revealed that these species can also be involved in selective oxygen insertion.

High-fidelity pairing of nucleic acid polymers is important in the development of sensors and for the application of DNA nanotechnology. Here, a set of hybridization probes is described that discriminates single-base changes with high specificity. The probes function robustly across many different temperatures, salinities and nucleic acid concentrations.

The bottom-up construction of covalently linked molecular architectures on surfaces has recently been demonstrated, but only rather simple structures can be obtained in such one-step connection processes. A sequential approach has now been used to induce the selective connection of molecules with a programmed reactivity, enabling network formation with high selectivity.

The pre-RNA-world hypothesis postulates that RNA was preceded in the evolution of life by a simpler genetic material. Here, Darwinian evolution methods were used to generate a threose nucleic acid (TNA) aptamer. This result provides evidence that TNA could have served as an ancestral genetic system during an early stage of life.

A 16-member diastereoisomer library known to contain macrosphelides A and E is synthesized as a mixture with the aid of a new encoding strategy for fluorous mixture synthesis. A simple process of sequential demixing and tag removal provides each of the isomers in individual, pure form. Analysis of the other library members ultimately leads to a structural reassignment for macrosphelide D.

Light-sensitive ligands can be used to regulate neurobiological receptors with high spatiotemporal precision. Here, the optochemical control of neuronal nicotinic acetylcholine receptors, using both photoswitchable tethered agonists and antagonists, is described. These rationally designed hybrid photoreceptors will facilitate the investigation of the physiological and pathological functions of nicotinic receptors in the brain.