Reviews & Analysis

Nature's enzymes are remarkably efficient at catalysing highly specific reactions with extraordinary selectivity. The ability to design enzymes for any desired reaction is a huge challenge. Here, the advances in the development of artificial enzymes are discussed with a particular focus on the computational advances that bring this challenge closer to reality.

Chemists are like detectives: they like to know 'whodunit' during a catalytic reaction. Combining advanced electron microscopy with intelligent molecular design has now provided strong evidence for the presence of a highly active site within a complex catalytic solid.

Shining circularly polarized light into a suspension of racemic amino-acid-derivative crystals in a saturated solution and then grinding them results in enantiomerically pure crystals. This evolution is shown to be directed by an unknown chiral product.

The conformational structure of a molecule can have important effects on its interactions and properties, but studying such effects is made difficult by the challenge of separating different conformers. Their spatial separation has now been achieved using an electric field — allowing the possibility of isomer-specific studies.

Proton-conducting solids are crucial components in a variety of electrochemical and energy-conversion devices. A porous metal–organic framework loaded with guest molecules displays both proton-conducting and gas-tight properties, affirming its potential as a fuel cell membrane.

In spite of the many functions of copper proteins within biology, those that contain a single copper ion can be divided into two classes, based in part on their spectroscopic properties. An artificial 'type 0' protein combines some properties of both, and may offer a route to stable catalytic processes.

The formation of a phosphine oxide with its strong P=O bond is the driving force for the classical Wittig reaction, but is wasteful and can pose problems during purification. A new development allowing the use of catalytic phosphorus reagents promises to clean up olefination chemistry.

Encapsulating guest molecules inside host structures ranging from soft, flexible enzymes to rigid, porous zeolites has led to developments in many areas, including catalysis, sensing and separation. This Review highlights how metal–organic frameworks — materials formed by linking metal centres with organic ligands — can combine softness with regularity to produce dynamic, yet crystalline, structures that may prove useful for a range of applications.

Chemists have long relied on techniques that give indirect hints and clues as to the structure of the molecules they study, but advances in scanning probe microscopy provide a glimpse of the individual atoms and bonds within pentacene.

Synthetic vesicles with membranes made from amphiphiles that are fluorescence acceptors encapsulate donor molecules in their cores, and emit different proportions of red, blue and green light depending on pH. The balance of these coloured emissions at pH 9 results in white fluorescence.

The host–guest properties of metal–organic frameworks have usually relied on molecular separation by the pore aperture or non-specific binding with the pore walls. Incorporating supramolecular recognition units into the frameworks has now enabled the docking of a specific guest.

Identifying inhibitors of protein–protein interactions is an ongoing challenge in the field of drug design, but the use of peptide fragments based on a known binding interface is showing promise.

Inorganic semiconductors have long been used to construct rectifying diodes, but making them out of single molecules has remained a challenge. Now, two separate studies have induced rectification behaviour within molecular systems through different approaches.

Altering the properties of materials by using an external signal, such as light, heat or mechanical stress, is attractive for the preparation of functional materials in diverse fields. This Perspective focuses on liquid and solid materials that change the colour of their luminescence under mechanical pressure, and highlights the structural changes involved.

The development of general synthetic strategies for the prepartion of oligonucleotides and peptides has enabled them to be made routinely — often using automated systems. Making complex oligosaccharides is much less straightforward, but advances in areas such as one-pot multi-step protecting-group manipulations, stereoselective glycosylation protocols and chemo-enzymatic methods are offering new opportunities for carbohydrate chemistry.

Improvements to the efficiency and lifetime of polymer electrolyte membrane fuel cells can be realized by finding more active and stable electrocatalytic cathode materials. A computational search has found two such alloys and confirmed their enhanced properties experimentally.

By studying non-covalent assemblies in the gas phase, it is possible to examine the mobility of the components within a single complex — rather than between different complexes — using hydrogen/deuterium exchange reactions.