Adventurous Research in Chemistry at the University of Bristol 2005

化学研究正在快速发展，因此，化学现在通过从分子行为的角度看待问题来解决其他传统科学领域（如生物学）的重要问题。人们早就知道，许多生物学上重要的分子，如氨基酸和蛋白质，它们的原子都有优先排列，这种现象称为同手性。分子中的手性意味着分子在镜子中的反射会导致另一个分子无法完全适合起始分子，就像你的右手和左手并不完全匹配一样。生物分子对特定手性形式的明显偏好长期以来一直困扰着科学家，因为制造这些分子的正常方法应该产生等量的不同手性形式，而不是对一种或另一种的整体自然偏好。对于自然同手性的原因已经提出了一些建议，但是这些论点中存在的弱点阻止了它们发展成为令人信服的理论。在该提案中描述的第一个项目中，提出了一种形成天然手性分子的新方法，该方法涉及将许多小分子（可能在地球上进化生命之前就存在的类型）连接在一起，形成称为聚合物的较大分子。如果这些聚合物可以作为一个支架，其他小分子以同样的方式连接在一起，那么这些手性聚合物的额外拷贝将比其他具有不同手性性质的分子更快地被制造出来。第二个项目将开发一个火柴盒大小的微型核磁共振光谱仪。NMR是一种非常强大的化学技术，可以测量分子的形状和结构。在医学上，它被广泛用于MRI扫描仪，以拍摄身体器官的图像。大多数核磁共振机器都很大（比一个人还大），很重，而且非常昂贵，因为它们需要大磁铁才能很好地工作。在这个项目中，将建造一个更小的核磁共振机器，它使用无线技术向计算机发送信号。它将比普通核磁共振机器便宜得多，并且作为化学实验室、工业研究实验室和制造工厂以及医学实验室的标准设备更方便地拾取和使用。第三个项目重点关注化学的核心领域，即开发新的方法来制造新的、有趣的和重要的分子（称为化学或分子合成）。苯环（六个碳原子连接成六边形）存在于许多分子中，化学家希望能够控制苯环中不同碳原子形成新键的方式。例如，如果六边形顶部的1号碳原子已经与另一个原子（如氧原子）键合，则相对容易与相邻的碳原子（环中的2号和6号原子）形成新的键。虽然目前还不能精确地将化学键连接到相邻的两个碳原子（环上的3号和5号）上，但如果能做到这一点，就能制造出许多新的分子。该项目将测试一些令人兴奋的新想法，即如何将原子仅添加到3位和5位（所谓的Meta位）的碳原子上，从而开辟化学合成的新领域。

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.