Adventurous Research in Chemistry at the University of Bristol 2005

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Research in chemistry is evolving fast and, as a result, chemistry now addresses important questions in other traditional scientific areas such as biology by looking at problems from the point of view of how molecules behave. It has long been known that many biologically important molecules such as amino acids and proteins have preferred arrangements of their atoms, a phenomenon known as homochirality . Chirality in a molecule means that a reflection of the molecule in a mirror results in another molecule that cannot fit exactly over the starting molecule, just as your right and left hands do not exactly match. The clear preference for particular chiral forms in biological molecules has puzzled scientists for a long time because the normal ways of making these molecules should produce equal amounts of the different chiral forms, giving no overall natural preference for one or another. Some suggestions have been made for reasons for the natural homochirality, but there are weaknesses in the arguments that have stopped them being developed into convincing theories. In the first of the projects described in this proposal, a new way to form a naturally chiral molecule is suggested, which involves connecting together a number of small molecules (of the type that might have been present before life evolved on Earth) to form larger molecules called polymers. If the polymers can then act as a scaffold on which other small molecules join together in the same way, extra copies of these chiral polymers will be made more quickly than other molecules with different chiral properties.The second project will develop a miniature NMR spectrometer the size of a matchbox. NMR is a very powerful technique in chemistry that allows the shapes and structures of molecules to be measured. In medicine it is widely used in MRI scanners to take images of the organs in the body. Most NMR machines are large (bigger than a person), heavy and very expensive because they need big magnets to work well. In this project, a much smaller NMR machine will be built that uses wireless technology to send a signal to a computer. It will be considerably cheaper than normal NMR machines, and much more convenient to pick up and use as a standard piece of equipment in chemistry labs, industrial research labs and manufacturing plants, and medical labs.The third project focuses on an area at the heart of chemistry, which is to develop new ways to make new, interesting and important molecules (known as chemical or molecular synthesis). Benzene rings (six carbon atoms joined in a hexagon) occur in many molecules and chemists would like to be able to control the ways in which new bonds are formed to the different carbon atoms in a benzene ring. If, for example, carbon number 1 at the top of the hexagon is already bonded to another atom such as oxygen, it is relatively easy to make new bonds to the carbon atoms next to it (atoms number 2 and 6 in the ring). Making bonds specifically to the next two carbon atoms (numbers 3 and 5 round the ring) cannot yet be done in a precise way, but if this could be done many new molecules could be made. This project will test some exciting new ideas about how to add atoms only to the carbons at sites 3 and 5 (so-called meta positions) and thus open up new areas of chemical synthesis.