Volume 1 Issue 3, June 2009

Diamonds may be forever, but are some other forms of carbon merely passing fads? Stuart Cantrill considers why carbon often seems to be a chemist's best friend.

Will robots take the drudgery out of lab work, and have you got a nose for isotopes?

The formation of robust monolayers of organic molecules on graphene substrates not only sweeps this material's defects under a self-assembled carpet, but may help it achieve its full potential as a building block for molecular electronic devices.

Progress in NMR spectroscopy has been held back by sensitivity issues inherent to the way the measurements are taken. Now, two separate studies show how simple chemical processes can be used to unveil NMR's sensitive side

Cyclic molecules have fascinated chemists for many years and researchers have now made nanoscale macromolecular 'doughnuts' that are large enough to be imaged with an atomic force microscope — providing direct visual proof of their cyclic topologies.

Stretching proteins strung together between the tip of an atomic force microscope and a surface results in mechanical tension that influences the rate at which disulfide bonds are cleaved under basic conditions, and reveals an unexpected switch in reactivity above a certain threshold force.

Enhancing the solubility of single-walled carbon nanotubes through non-covalent bonds has led to an improvement in our ability to probe and understand their interactions with electron donors and acceptors.

Using the protein of interest as a template, weakly binding ligands can be chemically linked to produce protein-binding agents that can compete with nature's own.

Exceptional catalysts will be required to produce hydrogen and oxygen from water. Copying multinuclear metal complexes in enzymes is promising, but not the only route. A mononuclear ruthenium complex has been developed that both makes hydrogen and forms oxygen–oxygen bonds through a mechanism different to those in nature.

Fragment-based drug discovery is an approach that relies on the ability to identify weakly binding drug fragments using sophisticated screening techniques. Binding can be optimized while maintaining favourable physical properties of the drug, which should have a positive impact on the attrition rates of new drug candidates.

The use of protecting groups has been, and remains, instrumental in the development of organic synthesis. However, designing protecting-group-free strategies offers the challenge of developing useful new chemoselective processes as well as being inherently more step- and atom-economic.

The unique physical properties of graphene make it a promising material for the construction of nanoelectronic devices. In order to tailor its surface properties and enable it to be integrated with other components, it has now been shown that stable and robust organic monolayers can be formed on graphene at room temperature.

A topologically non-trivial metallosupramolecular structure is formed by a Pd₄L₄ complex in which interweaving and twisting of the ligands results in both Solomon's Link and figure-of-eight ring motifs. In the solid state, six of these complexes assemble into a hollow spheroid that closely resembles a stellated truncated hexahedron.

Aerogels made from metal–sulfur networks show high absorption of conjugated organic molecules and mercury ions and can easily separate H₂ from CO₂. Compared with the conventional sulfided Co-Mo/Al₂O₃ catalyst, these spongy, random porous networks are twice as active towards the hydrodesulfurization of thiophene.

An organocatalytic cascade reaction allows the rapid construction of (+)-ricciocarpin A, which exhibits potent molluscicidal activity against the water snails Biomphalaria glabrata. The concise synthesis also allowed the synthesis of five analogues, one of which was shown to have significantly improved biological activity.

Deviations from the normal bonding behaviour add to our understanding of bonding models and inform computer simulations. Chlorotrinitromethane has an extremely short carbon–chlorine bond and its solid-state structure has now been determined. Using a combination of crystallography and computation, its intra- and intermolecular interactions have also been studied.

Mechanical stretching of a protein can be studied in detail using single-molecule experiments, and is shown to have an accelerating effect on its reaction with a nucleophile. The observation of a dramatic switch in the effect above a threshold force suggests an abrupt change in protein conformation and a change in reaction mechanism.

Using carbon nanotubes in electronic or photovoltaic devices generates active metastable states. These elusive species are hard to characterize because of the polydisperse and aggregate nature of nanotube bundles. A complete characterization of the radical–ion pair state has now been achieved using a range of techniques.

Like all noble gases, xenon is colourless, odourless and inflammable — but it is also more reactive, and much rarer, than its lighter relatives. Ivan Dmochowski ponders how xenon, though initially slow to earn a spot in the periodic table, is now at the forefront of advances in science and technology.