New high performance transition metal catalysts for sustainable reductive processing of chemical feedstocks

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We are all familiar with the catalytic convertors in the back of cars, turning polluting gases like nitrogen oxides and carbon monoxide into chemicals that are better for our air. My work will focus on a similar principle, I will be looking at the metal iridium to see if I can use it to introduce carbon dioxide, or specifically the carbon atom in carbon dioxide, onto nitrogen atoms in molecules. Carbon dioxide is currently a readily available waste product that as a society we are keen to remove from our atmosphere due to its enhancement of the greenhouse effect, and so this project would allow us to explore new ways of doing this. Also, molecules with nitrogen atoms in them, especially ones with carbon attached to them in the way I have described, are very common in modern drugs and other chemicals, such as fertilisers, that are of vital importance to society today.What is special about this work is, thus far, no other academic group has been able to methylate(1) nitrogen atoms using iridium metal and mild reaction conditions(2) yet. Being able to do it this way would provide new routes to a huge variety of chemical compounds, some of which could be useful to industry. A key part of this work will not only be making this reaction with carbon dioxide as good as possible, but also investigating how the reaction happens, its mechanism. This will include both experimental and computational work and by understanding the mechanism it will make it easier to know what reactions should be plausible and how to potentially improve the catalyst in the future.Iridium is considered to be a part of the 'Precious Metal Group', alongside the likes of gold, silver and platinum. In fact, iridium is much more expensive than any of these metals, and over the last few years has been subject to volatile prices. Luckily, for this type of work very, very small amounts of iridium are needed for the reaction, and at a lab scale this means just a gram of iridium can last many months. Despite this, iridium is a much more finite and expensive resource than a lot of other metals, like iron, cobalt, nickel etc. and it would be highly desirable to eventually try to progress this work to using a cheaper, more readily available metal.This project falls with the ESPRC Catalysis Research Area.(1)The word used to describe adding a carbon atom-with three hydrogen atoms on it-onto something else.(2) Reactions done at/close to room temperature and pressure.