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The Alchemist ups the anti this week with a look at aromaticity while the salty problem of fracking is high on the agenda once more but this time with a prehistoric perspective. Cleaner fuels might soon be available thanks to nanoscopic scrubbers while a new form of water emerges from the limbo between liquid and vapor when a little oil is added to the mix. Synthetic chemists have given a much needed shot in the arm for antiviral flu drugs and there's a XMaS bonus in the offing for European X-ray scientists.




An international team has brought the story of aromaticity full circle from the apocryphal tale of Kekule's dream of Ouroboros the snake. Jonathan Sessler and colleagues have stabilized an aromatic molecule in the anti-aromatic form, a rare achievement, using rational design modifications on a porphyrin compound they first synthesized in 1992. The final product is a meso-pentafluorophenyl-substituted o-phenylene-bridged annulated rosarin, with the bulky groups forcing the previously aromatic skeleton into the antiaromatic state. The team also identified, but are yet to name, an intermediate compound that lies between the aromatic and the anti-aromatic state in a kind of chemical limbo of planarity and non-planarity and electron resonances.





Researchers at Penn State University have found that the brine that flows out from gas wells in the Marcellus Shale region after hydraulic fracturing, commonly known as fracking, is much saltier than seawater into which it pours. More worrying is that it also contains relatively high levels of metallic elements, including radium and barium. The data suggest that the brine has an ancient source in the Paleozoic era rather than being simply the washings of the fracking process itself. Improper disposal of the flowback can lead to unsafe levels of these and other constituents in water, biota and sediment from wells and streams, the researchers note. The high salinity and toxicity of these waters must be a key criterion in the technology for disposal of both the flowback waters and the continuing outflow of the production waters.





Mats containing nanoscopic fibers of metal oxide are much more efficient at scrubbing (removing) sulfur compounds from petroleum-based fuels, according to a study at the University of Illinois. The materials are much more effective than conventional scrubbers and could improve performance for fuel-based catalysis as well as making cleaner city fuels less expensive for drivers. The nanofiber mat is more reactive than its bulk counterpart, allowing complete sulfur removal with less material. The material remains stable and active for several cycles as well as precluding sintering, or clumping, of the catalyst which is a problem with other nano-structured catalysts.





Water is not only essential for life as we know it, it presents countless anomalous properties that even the hardiest of chemist struggles to explain at times. Now, an entirely new form of water has been discovered lying between liquid and vapor phase when hydrophobic compounds are added to the mix. Given water's critical place in life, understanding its intriguing behavior in such situations is important to understanding life itself and the stuff from which it is made, the proteins and other biomolecules. Researchers at Purdue University used Raman scattering and a novel multivariate curve resolution to boost the signal to noise ratio in their analysis to reveal the new form of water.





Influenza can be lethal. There are up to five million cases each year worldwide and half a million die following infection with the virus. Chemistry World now reports that researchers from Australia and the USA have developed an approach to an antiviral drug that gives higher yields and greater efficacy than currently available with the likes of zanamivir and oseltamivir. Benjamin Fraser from the Australian Nuclear Science and Technology Organisation in collaboration with Alastair Draffan at Biota Holdings in Melbourne and K. Barry Sharpless at the Scripps Research institute in San Diego have designed a higher-yielding synthesis route, which can also prepare the dimers with new linker functionality using a known cycloaddition reaction. The dimeric products are up to 3000 times more potent than zanamivir tests show.





The UK government has given an early present of GBP 6million (about US$10million) to XMaS, the mid-range X-ray facility at the ESRF (European Synchrotron Radiation in Grenoble). The funding will allow scientists to continue exploring matter at the atomic level. The device was first used for X-ray magnetic scattering hence the name but its scientific reach is now much greater with 20 active UK research groups (about 100 researchers) using it in materials science, physics, chemistry, soft condensed matter and biomaterials. The facility is owned by the Universities of Liverpool and Warwick and funding comes through the Engineering and Physical Sciences Research Council and the UK Government's Department for Business Innovation and Skills.