The Nobel Prize in Chemistry was awarded on Wednesday to Benjamin List and David W.C. MacMillan for their development of a new tool to build molecules, work that has spurred advances in pharmaceutical research and lessened the impact of chemistry on the environment.
Their work, while unseen by consumers, is an essential part in many leading industries and is crucial for research.
Chemists are among those tasked with constructing molecules that can form elastic and durable materials, store energy in batteries or inhibit the progression of diseases.
But that work requires catalysts, which are substances that control and accelerate chemical reactions without becoming part of the final product.
“For example, catalysts in cars transform toxic substances in exhaust fumes to harmless molecules,” the Nobel committee said in a statement. “Our bodies also contain thousands of catalysts in the form of enzymes, which chisel out the molecules necessary for life.”
The problem was that there were just two types of catalysts available: metals and enzymes.
In 2000, Dr. List and Dr. MacMillan — working independently of each other — developed a new type of catalysis that reduced waste and allowed for novel ways to construct molecules.
It is called asymmetric organocatalysis and builds upon small organic molecules.
“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,” said Johan Aqvist, chairman of the Nobel Committee for Chemistry.
Why is the work important?
Virtually everyone on the planet has come across a product that has benefited from a chemist’s expertise. The process of using catalysts to break down molecules or join them together is essential in industry and research.
The 2021 Nobel Prizes
Catalysis is what makes plastics possible; it also allows the manufacture of products such as food flavorings to target the taste buds and perfumes to tickle the nose.
About 35 percent of the world’s gross domestic product involves chemical catalysis.
But until 2000 and the discovery by the Nobel laureates, the tools at the disposal of chemists were the equivalent of hammers and chisels.
“If we compare nature’s ability to build chemical creations with our own, we were long stuck in the Stone Age,” the Nobel committee wrote.
In nature, enzymes do the work of constructing the molecular complexes that give life its shape, color and function.
The catalysts previously used by chemists could be broken down into two groups: metals or enzymes.
“Metals are often excellent catalysts because they have a special ability to temporarily accommodate electrons or to provide them to other molecules during a chemical process,” the committee wrote. “This helps loosen the bonds between the atoms in a molecule, so bonds that are otherwise strong can be broken and new ones can form.”
But to work, some metal catalysts need to be in an environment free of oxygen and moisture — hard to achieve in many large-scale industries. And many such catalysts are heavy metals, which can be harmful to the environment.
In nature, enzymes are used as catalysts with astounding precision. That is the process by which complicated — and vital — molecules such as cholesterol and chlorophyll are formed.
Because enzymes are so efficient, researchers in the 1990s tried to develop enzyme variants as catalysts to drive the chemical reactions needed by industry and in manufacturing.
But the process used before the discoveries made by Dr. List and Dr. MacMillan led to vast amounts of waste.
“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 committee wrote. “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 Dr. List and Dr. MacMillan — asymmetric organocatalysis — offered a solution. The new process paved the way for creating molecules that can serve purposes as varied as making lightweight running shoes and inhibiting the progress of disease in the body.
“Why did no one come up with this simple, green and cheap concept for asymmetric catalysis earlier?” the committee wrote. “This question has many answers. One is that the simple ideas are often the most difficult to imagine.”
Who are the winners?
Dr. MacMillan is a Scottish chemist and a professor at Princeton University, where he also headed the department of chemistry from 2010 to 2015. He earned his Ph.D. in inorganic chemistry at the University of California, Irvine, in 1996 before accepting a postdoctoral fellowship at Harvard University. His research has focused on innovative concepts in synthetic organic chemistry.
Dr. List is a German chemist, born in Frankfurt, and director at the Max Planck Institute for Coal Research in Mülheim an der Ruhr, Germany. His research team, List Laboratory, focuses on the “invention of new strategies for the development of perfect chemical reactions,” according to the Institute’s website. His team posted a video on Twitter celebrating his Nobel Prize after the announcement. He received his Ph.D. in 1997 from Goethe University Frankfurt, before he was appointed to work as an assistant professor at the Scripps Research Institute in California. He is also an honorary professor at the University of Cologne, in Germany.