Articles in 2012

Milling and grinding, long used to alter the chemical and physical properties of materials, have recently garnered interest as alternatives to traditional solution-based syntheses — but these reactions remain difficult to monitor. High-energy synchrotron X-ray radiation has now enabled the in situ observation, in real time, of solid-state transformations occurring during the mechanochemical syntheses of metal–organic frameworks.

The in situ trapping of pyridynes is an efficient method for the generation of a variety of substituted pyridines but, until now, the method has been hampered by a lack of regiocontrol. Here, proximal halide and sulfamate substituents are shown to perturb pyridyne distortion and thus govern regioselectivities in pyridyne reactions.

An artificial transfer hydrogenase, based on the incorporation of a biotinylated iridium-piano-stool complex in streptavidin, is shown to be fully compatible with a range of biocatalysts. The location of the active metal centre inside the protein scaffold efficiently prevents mutual inactivation processes and enables the concurrent interplay with oxidative enzymes.

The infrared spectra of gas-phase protonated water clusters and protonated liquid water have been calculated from molecular simulations using a ‘clusters-in-liquid’ approach, which is restricted to a selected set of charged atoms. The infrared absorption due to the central proton in the H₂O···H⁺···OH₂ moiety is found near 1,740 cm⁻¹.

Michelle Francl suggests that chemists should keep on name-dropping.

Uranium and manganese cations have been combined in a wheel-shaped supramolecular assembly that retains its magnetic spin state after the external field is removed, with a high barrier to its relaxation. This cluster supports recent predictions of the usefulness of the actinides in single-molecule magnetic devices.

The deposition of cobalt-phosphate onto photocatalytic haematite improves its ability to split water and thus create clean hydrogen fuel. The source of this improvement is, however, not yet understood, and now two separate studies suggest different roles for the deposited cobalt-phosphate.

The reversible reduction and evolution of oxygen are the key processes to be mastered before high-energy rechargeable lithium–air batteries can be successfully created. Now an advance towards this goal has been achieved with the synthesis of a pyrochlore catalyst that benefits from a mesoporous structure and oxygen deficiencies.

In 1972, Baird published rules describing aromaticity and antiaromaticity in the lowest triplet excited states of annulenes. The fortieth anniversary of Baird's rules — which are the reverse of Hückel's rules for aromaticity and antiaromaticity in the ground state — ought to be celebrated before 2012 comes to an end.

Dennis P. Curran invites everyone to join the dawning new era of organic synthesis.

For historical reasons, plutonium brings to mind nuclear weapons. Jan Hartmann brings another side of element 94 to attention, which features an upcoming trip to its eponymous celestial body.

Bioactive molecules frequently contain several very similarly reactive functional groups and it can thus be difficult to cause one to react selectively. Now, two separate studies present complementary approaches to this desirable goal.