Adventurous Research in Chemistry at the University of Bristol 2005

化学研究发展迅速，因此，化学现在从分子行为的角度来研究其他传统科学领域的重要问题，如生物学。人们早就知道，许多具有生物重要性的分子，如氨基酸和蛋白质，都喜欢它们的原子排列，这一现象被称为同质。分子中的手性意味着该分子在镜子中的反射导致另一个分子不能完全匹配起始分子，就像你的右手和左手不完全匹配一样。生物分子对特定手性形式的明显偏好一直困扰着科学家很长一段时间，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，不会给出整体的自然偏好。对于自然同质性的原因，已经提出了一些建议，但这些论点存在弱点，使它们无法发展为令人信服的理论。在这项提案中描述的第一个项目中，提出了一种形成自然手性分子的新方法，包括将一些小分子(可能是在地球上生命进化之前就存在的那种类型)连接在一起，形成称为聚合物的大分子。如果聚合物可以作为支架，其他小分子以同样的方式连接在一起，这些手性聚合物的额外拷贝将比其他具有不同手性的分子更快地制造出来。第二个项目将开发火柴盒大小的微型核磁共振光谱仪。核磁共振是一种非常强大的化学技术，它可以测量分子的形状和结构。在医学上，它被广泛用于核磁共振扫描仪，以拍摄人体器官的图像。大多数核磁共振仪都很大(比人还大)，而且很重，而且非常昂贵，因为它们需要大磁铁才能正常工作。在这个项目中，将建造一台小得多的核磁共振仪，它使用无线技术向计算机发送信号。它将比普通的核磁共振仪便宜得多，而且在化学实验室、工业研究实验室和制造厂以及医学实验室中作为标准设备携带和使用要方便得多。第三个项目专注于化学核心领域，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(六个碳原子连接成一个六边形)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，如果六边形顶部的碳1已经与氧等另一个原子成键，则相对容易与其旁边的碳原子(环中的原子2和6)形成新的键。专门针对下两个碳原子(环上的数字3和5)建立键还不能以一种精确的方式完成，但如果可以做到这一点，就可以制造许多新的分子。这个项目将测试一些令人兴奋的新想法，关于如何只将原子添加到第三和第五位(所谓的间位)的碳上，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.