Five minutes with Dr Silvia Diez-GonzalezSenior Lecturer in Catalysis

Dr Silvia Diez-Gonzalez

1. Tell us about your research in a nutshell

My research group is trying to make organic synthesis as easy as possible. This means designing new, efficient reactions that use solvents and catalysts in interesting ways.

Most recently we have started looking specifically at reaction mediums and how the solvents involved can also influence the reactivity and the stability of the compounds we are trying to make.

2. Tell us about some of your projects
 

I’m very happy about the latest pieces of work that my group have published.

In one of them we are making molecules that are known but not very widely used. This is because they are unstable and so the process to make them is very restrictive. However, we have modified the solvent in the reaction and replaced it with a deep eutectic solvent.

The problem here however is the inefficiency of the reducing agent. Of course at the scale of our laboratory the waste from this reaction isn’t a problem. But if you’re attempting a more complicated reaction or want to work on an industrial scale then you would have tonnes of waste from the reaction."

This type of solvent is very neat: it involves two solids that, when mixed, form a liquid because the melting point of the combination is much lower. The properties of this solvent make it easier to isolate the products we are trying to form. Crucially the whole process is thermal, with no catalyst at all and the solvent is bio-degradable and non-toxic. As a proof of concept it is very exciting.

On the other side of our work we have been working on making a catalytic version of a reduction that is popular with biomolecules because it’s very selective. The problem here however is the inefficiency of the reducing agent. Of course at the scale of our laboratory the waste from this reaction isn’t a problem. But if you’re attempting a more complicated reaction or want to work on an industrial scale then you would have tonnes of waste from the reaction.

We have therefore been working on a copper-catalysed version of the reaction, and have found that with the right catalyst, we can use the reaction solvents as reducing agents. We are still learning how this works but we can already see that we can improve the system by changing the structure of the catalyst and making an elegant version of the reaction that does not use any additional reagent/chemical. In terms of efficiency this is excellent progress for this reaction.

3.  What impact could your research have for our industry partners?

When I was studying for my PhD in France, I was frustrated that available catalysts were either too expensive or too sensitive or would require four steps to be effective and even then might not work. It inspired me to try to create more user-friendly catalysts that had the potential to be useful to others.

A simpler synthesis has natural implications for cost and efficiency. That is why having catalysts that don’t need controlled environments and solvents that don’t require extra special precautions – which is what we are working on – has a number of advantages for everyone, especially industry.

The advantages of our reactions are also that they more sustainable because they minimise the resources that are needed. If we think about the bigger picture of green chemistry and the circular economy these are important factors that we all need to take into account.

4.  What's interesting you most about your field at the moment?

I think if I’m only going to spend my life doing one thing I might as well make them my focus because at least I won’t get bored."

My personal interest is in the role of the transition metals, which are a never-ending source of inspiration for me! This area of chemistry boomed in the 60s and 70s but despite all the efforts of the research community we are still able to find new reactions and applications by playing around with them.

I think if I’m only going to spend my life doing one thing I might as well make them my focus because at least I won’t get bored.

5.  Who/what sectors would be interested in hearing more about your research?

The sectors that would find our reactions particularly relevant are:

  • Fine chemicals
  • Pharmaceuticals

Learn more about Imperial’s Synthesis and Catalysis research theme