Reviews & Analysis

Monitoring the dynamics of a single molecule is impeded by their motion in solution, and immobilizing them without changing their properties is problematic. By using a trapping method that counteracts a molecule's Brownian motion, the complex dynamics of a fluorescent protein, allophycocyanin, have been investigated.

Electromerism is an unfamiliar concept to many chemists and refers to molecules that are not conventional isomers but instead differ in how the electrons are distributed across their structure. A novel example of such electromers has now been demonstrated.

Supramolecular gels, which rely on non-covalent interactions, are typically fragile. Now, hydrogels that possess remarkable mechanical strength combined with the ability to rapidly self-heal have been built through multiple non-covalent interactions.

The field of organocatalysis has grown rapidly in the past decade to become, along with metal catalysis and biocatalysis, a third pillar of asymmetric catalysis. Here, progress in the use of organocatalytic cascade reactions for total synthesis is reviewed. The elegance and efficiency of such cascades mean that they have emerged as a powerful tool in synthetic organic chemistry.

A linear molecule containing three bipyridine ligands can be wrapped around a single metal-ion template to form an open-knot complex. The loose ends of the knot can be 'tied' together through esterification or olefin-metathesis reactions to form closed knots that do not unravel when the metal template is removed.

Chemical reactions of fullerenes and metallofullerenes lined up inside single-walled carbon nanotubes can be monitored at the atomic scale inside an aberration-corrected transmission electron microscope.

Yttrium-based catalysts can be used to stitch together two different lactone monomers in an alternating fashion to produce polyesters with well-defined primary structures. The ability to control the sequence of building blocks in polymers with increasing levels of precision offers new opportunities for tailoring the properties of designer synthetic macromolecules.

The stereochemical lability of cycloalkylzinc reagents combined with a large difference in reactivity between epimers has been exploited to form a wide variety of interesting organic compounds with both high yields and diastereoselectivities.

A molecular 'walker' can be made to move up and down a molecular 'track' by alternately locking and unlocking the two different types of covalent bonds that join the two components together. By changing the conditions under which one of the bond-forming/bond-breaking processes occurs, a directional bias for walking can be achieved.

The use of conventional computers to calculate molecular properties is hindered by the exponential increase in computational cost on increasing the size of the molecules studied. Using quantum computers could be the solution and the initial steps are now being taken.

Quantum tunnelling can at times be the cause of kinetic isotope effects, and in these cases conventional wisdom has been that molecules with isotopes of larger mass will react more slowly. New calculations, however, predict that sometimes the reverse should be true.

An enzyme that is unusually tolerant of a truly broad range of substrates can catalyse aldol-type chemistry on sugars in which the various hydroxyl groups are protected. The new methodology combines some of the most important advantages of enzyme and small-molecule catalysis.

The formation of single-layer-thick molecular networks at metal surfaces is governed by the interplay between intermolecular and interfacial interactions. This Review highlights how, with films built by vacuum deposition, these interactions can be modulated to form substrates that may be useful as catalysts or templates for further deposition steps.

Embedding platinum nanoparticles in a polymer matrix produces a system that reacts like a homogeneous catalyst, but provides the stability and separation advantages of a heterogeneous one.

Although it may seem counter-intuitive, the attraction between positively charged radical ions offers a new approach to driving controlled motion in molecular machines.

Small-molecule enzyme-inhibitors often display insufficient affinity and selectivity for their targets causing unwanted side effects when used as drugs. Molecularly imprinted polymers prepared using the enzyme as a template could offer a solution.

Synthetic procedures for making nanoparticles often result in samples that contain a range of different particle sizes. By using hollow self-assembled metal–organic spheres as templates, however, it is possible to make silica nanoparticles with uniform shapes and sizes in a precisely controlled fashion.

Among the wide variety of synthetic processes that chemists have developed, only a few can be carried out under physiological conditions. A condensation reaction that is controlled by the constituents of cells has led to the formation of nanostructures within living cells.