What Is Asymmetric Organocatalysis? Benjamin List, David Macmillan Win Chemistry Nobel Prize

The Nobel Prize in Chemistry has been awarded to Benjamin List and David W.C. MacMillan for the development of a tool known as "asymmetric organocatalysis."

The chemists, affiliated with Max-Planck-Institut für Kohlenforschung, Germany, and Princeton University respectively, will share 10 million Swedish kronor (about $1.1 million) after the winners were announced the winners on Wednesday.

Given its new fame, many will now ask: what exactly is asymmetric organocatalysis?

Asymmetric organocatalysis is a precise new tool for the construction of molecules that the Royal Swedish Academy of Sciences, which picks the winner, has called "ingenious."

Chemists can create new molecules by linking together small chemical building blocks. These artificially constructed substances can be used in a range of applications, ranging from storing energy in batteries to inhibiting the progression of diseases.

But manipulating these substances so they bond in the desired way is difficult.

"If we compare nature's ability to build chemical creations with our own, we were long stuck in the Stone Age," a statement from the Swedish Academy said. "Evolution has produced incredibly specific tools, enzymes, for constructing the molecular complexes that give life its shapes, colours and functions."

"Initially, when chemists isolated these chemical masterpieces, they just looked at them in admiration. The hammers and chisels in their own toolboxes for molecular construction were blunt and unreliable, so they often ended up with lots of unwanted byproducts when they copied nature's products."

When chemists construct new molecules they requires catalysts—substances that control and accelerate chemical reactions without becoming part of the final product. It was long thought that there were only two types of catalysts in principle: metals and enzymes.

'An Entirely New Level'

But in 2000, List and MacMillan developed a third type—asymmetric organocatalysis—independently of each other.

According to the academy, this discovery has taken molecular construction to "an entirely new level," helping to make chemistry greener but also making it much easier to produce asymmetric molecules.

"During chemical construction a situation often arises in which two molecules can form, which – just like our hands – are each other's mirror image," the statement from the academy said.

"Chemists often just want one of these mirror images, particularly when producing pharmaceuticals, but it has been difficult to find efficient methods for doing this.

The concept developed by Benjamin List and David MacMillan—asymmetric organocatalysis—enables chemists to do just that.

"This concept for catalysis is as simple as it is ingenious, and the fact is that many people have wondered why we didn't think of it earlier," Johan Åqvist, who is chair of the Nobel Committee for Chemistry, said in a statement.

Chemistry Nobel Prize winner Benjamin List
Co-winner of the 2021 Nobel Prize in Chemistry, Benjamin List, reacts prior to a press conference at the Max Planck Institute in Muehlheim, western Germany on October 6, 2021. INA FASSBENDER/AFP via Getty Images