Li named recipient of EPA Green Chemistry Award

August 26, 2001

Mark Miester
Phone: (504) 865-5714

When Chao-Jun Li submitted a paper on organic reactions in aqueous media to Chemical Reviews in 1993, reviewers were unanimous in their praise for the article, the first comprehensive review written on the subject. The reviewers, however, did have one question for Li: Who are you?

"The one question everyone raised was, I don't know whether he's a professor or what," recalls Li, then a 30-year-old post-doctoral fellow at Stanford. "It's very odd for someone who got his PhD very recently to publish by himself in that journal, which is the best review journal in chemistry worldwide. The authors are generally world authorities in their fields."

"But they also added another sentence," Li continues. "Who cares? It's a great article. It should be published. That more or less started my career."

Li, now professor of chemistry, went on to co-write a book based on his research, Organic Reactions in Aqueous Media (1997) and, with his research group at Tulane, produce more than 80 papers on catalytic reactions in water and air. In the process, he has become one of the nation's leading figures in green chemistry, the emerging movement that seeks to design chemical products and processes that reduce or eliminate waste and hazardous substances at the most fundamental level.

In June, the Environmental Protection Agency honored Li by presenting him with a Presidential Green Chemistry Challenge Award. The EPA presents the awards annually to four businesses and one academic researcher whose work has contributed to the goal of developing more environmentally friendly chemical products and processes.

Li was recognized for his work in designing a wide variety of transitional metal mediated and catalyzed reactions that can be accomplished in air and water. Traditionally, such reactions have been carried out in anhydrous organic solvents and in inert atmospheres. Organic solvents such as benzene and dioxane are highly toxic and using them in combination with inert gases such as nitrogen or argon increases the cost of reactions tremendously and often leads to catalyst deactivation.

By using metal catalysts, Li developed a method of generating reactions in water and air rather than the highly toxic organic solvents. The use of water as a solvent offers many advantages. In addition to its availability and cost effectiveness, water is not toxic, flammable or explosive. Also, unlike the organic solvents, water enables the metal catalysts to be readily recycled.

According to the EPA, the reactions developed by Li have widespread applications in the synthesis of pharmaceuticals, fine chemicals, petrochemicals, agricultural chemicals, polymers and plastics.

"[The reactions] affect everything relating to chemistry," Li notes. "These are very fundamental reactions. We're changing the way textbooks are written."

Li says the processes he and his team developed at Tulane are already being used in industry, particularly in pharmaceuticals and fine chemicals, and that Tulane's Office of Research is currently investigating patenting a number of the processes.

Li joined Tulane in 1994 after completing a postdoctoral fellowship at Stanford University, where he studied with Barry M. Trost, an early champion of green chemistry and the 1998 recipient of the academic Green Chemistry award. Li earned his BS in chemistry from Zhengzhou University in China and his PhD in organic chemistry from McGill University. He received a National Science Foundation Career Award in 1997.

Tulane University, New Orleans, LA 70118 504-865-5000