Stereokinetics / the optimisation of catalytic asymmetric reactions

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Many useful chemical substances are made of molecules that can exist in two forms which differ only in that the arrangement of their atoms are mirror images, very much like the arrangement of fingers and thumbs on left and right hands. These mirror image molecules can also be described as left-hand and right-hand versions. These mirror image molecules generally behave the same way in many chemical reactions, but when interacting with living systems they often behave very differently because the living systems are also made up of mirror image molecules. As in the shaking of hands, a right-hand to right-hand contact is very different to a right-hand to left-hand contact. Therefore if we are to make medicines to cure disease one of the properties must be whether it includes a left-hand or right-hand version of a molecule. We need to be able to decide which version will make the best medicine, and then work out a way of making it without making the other one at the same time. In our project we are working on this second problem. In our chemical reactions we are giving molecules the opportunity to become left or right hand versions. Like cars stopping at a T-junction, they can turn either left or right. We are interested in making a molecular traffic policeman that will stand at the junction and direct the flow of molecules only one way, either left or right as we decide. The policeman molecule has to be able to signal strongly enough, and fast enough to keep up with the flow of molecular traffic. Of course it should be possible to put a policeman in every car; we wouldn't have to get the signal timing right, but it would be rather expensive in policemen, so our way is better. If we can make better (and faster!) signalling policeman molecules we can make more of the mirror image molecules we want and fewer of the ones we don't. The research proposed here will revolutionalise the way new asymmetric catalysts (policeman molecules) can be developed by providing a simple method for direct comparison.These better and cleaner methods for controlling chemical reactions will result in the cheaper and more environmentally manufacture of chemicals, particularly on the large scales used by the chemical and pharmaceutical industries. This would be very useful for people making new medicines.