The 2021 Nobel prize in Chemistry was awarded by the Royal Swedish Academy jointly to Benjamin List and David W.C. MacMillan for the development of a new type of catalysis, called asymmetric organocatalysis, a precise new tool for molecular construction. “It’s a game changer. Like a new chess piece that is very, very powerful”, said Peter Somfai, member of the Nobel Committee, following the announcement of the 2021 Nobel Prize in Chemistry.
David MacMillan (top) and Benjamin List (bottom).
Molecules can exist in mirror image forms with different properties. To make medicines and other compounds we often want just one of these forms. Catalysts are substances than can speed up chemical reactions. Natural catalysts such as enzymes, build specific mirror image molecules all the time, but have complicated structures. Metal catalysts can play this role but are extremely sensitive to air and moisture effects, which at occasions can be harmful to the environment.
First, Benjamin List wondered if the single amino acids, from which enzymes are consisted of, could catalyze a reaction on their own. Having knowledge from previous studies on the amino acid proline, he used it to catalyze an aldol reaction and proved to be quite efficient. In addition, it formed one mirror image of the product much more often than any other amino acid previously used.
On the other hand, David MacMillan tried to develop alternatives to metal catalysts by using organic molecules. He identified an imidazolidinone molecule which could catalyze a carbon-carbon bond forming reaction and produced mostly one single mirror image of the final product. He coined the term ‘organocatalysis’ for the concept of catalyzing reactions using small organic molecules.
The significance of these novel organic catalysts lies to the fact that they are low-cost, environmentally friendly and can produce specific mirror images of molecules. They can be used one after another for various reaction steps, enhancing the efficiency of molecule-making.
“Organocatalysis has developed at an astounding speed since 2000. Benjamin List and David MacMillan remain leaders in the field, and have shown that organic catalysts can be used to drive multitudes of chemical reactions. Using these reactions, researchers can now more efficiently construct anything from new pharmaceuticals to molecules that can capture light in solar cells. In this way, organocatalysts are bringing the greatest benefit to humankind.”
Sweden's Royal Academy of Sciences concludes in its announcement.
Comentarios