New and tandem processes in asymmetric organocatalysis

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There is no doubt that the world's resources are becoming increasingly scarce and that mankind will have to find more ways of being efficient and scrupulous in its use of nonrenewable materials. In addition to this, there is the concern that any new processes, however efficient or inefficient, should be as environmentally compatible as possible. This project will be concerned with the development of chemical methodology that is compliant with these values, whilst at the same time addressing the huge issue of making potent compounds which are medicinally, very important.The definition of a catalyst is 'a substance which increases the rate of a reaction without itself being destroyed'. This means that it can be used in very small quantities, which is compliant with a more environmentally aware approach. However, in many cases these catalysts contain metals to co-ordinate and orchestrate specific reaction processes and this of course has the potential to both consume metal reserves as well as introducing an imbalance of such metals into the ecosystem. As a result, the area of organocatalysis has arisen. This is an area of chemistry concerned with the catalysis of reactions without any reliance on metals and one that this project addresses. One specific application of organocatalysis that has received much attention is its use in asymmetric synthesis. This immensely important area of chemistry stems from the fact that a carbon atom which is surrounded by four different groups, can have a non-superimposable mirror image, such as the left hand is of the right and asymmetric synthesis attempts to exclusively make one of these two 'hands'. The reason for this is that different handed molecules can interact with biological systems in different ways (imagine trying to shake someone's hand with your left hand / it's much more difficult!). An example of this is the molecule carvone, where one 'hand' smells of spearmint, but the other smells of caraway seed due to the different interaction of each 'hand' with the nasal receptors. In drug compounds, the difference can mean that one compound has a lower activity or have a completely different effect. So, clearly there is a need to be able to make molecules of one handedness, so that we know a specific biological response is given by one specific and known compound. This project will be concerned with the development of this area of chemistry and will take the understanding and applicability of it beyond today's level. Currently, there are a limited range of organocatalytic reactions and this research aims to introduce a new range of reactions to the chemist's toolbox. Ultimately, this research will investigate and establish new areas of chemistry which could help industries such as pharmaceuticals and agrochemicals to establish the efficient synthesis of drugs and biologically active compounds with less detriment to the environment or to the existing, but diminishing supplies of metals in the world.