The Nobel prize in chemistry 2021 goes to David Macmillan and Benjamin Liszt for the development of asymmetric organic catalysis. They received the prize for developing this ingenious tool for organic synthesis.
Asymmetric organic catalysis is set in the context of organic chemistry where we break and make bonds in organic molecules in a selective manner. So, what does asymmetric organic catalysis mean?
Well, if we start with the last term catalysis, that means that we are using a compound, a catalyst to drive another transformation, in this case, a chemical transformation. So, in this process when going from chemical starting materials to products, the catalyst is being regenerated so we can reuse it over and over.
And when we say organocatalyst or organocatalysis, we mean that the catalyst is a small and well-defined organic molecule that consists mainly of elements such as carbon, hydrogen, oxygen, nitrogen, maybe, sulfur, phosphorus, silicon, but no metals. An asymmetric organocatalysis that means that the catalyst, our small well-defined organic catalyst is asymmetric, that it's chiral.
So, our hands are mirror images of each other, they are chiral because we cannot put one on top of the other and make them look identical. And in the same way, as our hands are chiral, molecules can be chiral.
They are mir can be mirror images. So, if we use only one mirror image of the catalyst to drive our chemical transformation, we will get an enrichment of only one of two possible mirror images in the products.
So, we have a transfer of the chiral information from the catalyst to the products. So, asymmetric synthesis to make only one out of two possible mirror images of a molecule is highly important for a number of different applications.
Not the least in pharmaceutical synthesis, and to use a catalyst to do this is important from several perspectives. For one thing, we can get reactivity that we wouldn't see otherwise, we can make transformations that wouldn't occur without the catalyst.
Or we can get a transformation to go under milder reaction conditions such as slower reaction temperature which is good from an energy perspective. And also, with the catalyst, we reduce the amount of chemical waste that is produced.
This year's winners developed and conceptualized the principles for asymmetric organocatalysis in the beginning of the millennium. And after this, this research field exploded and became a flourishing field that developed many different catalysts and reactions that are now indispensable tools in the organic toolbox.
