Nobel Laureates garner medals minted in gold, but it was work with another noble metal—palladium—that earned three chemists the big prize this year. Richard F. Heck, Ei-ichi Negishi, and Akira Suzuki were jointly awarded the 2010 Nobel Prize in Chemistry “for palladium-catalyzed cross-couplings in organic synthesis.” Along with their medals, the three chemists will also share $1.5 million.
Palladium-catalyzed cross-coupling reactions, in which the metal is used to catalyze the formation of carbon-carbon bonds, are widely used to make complex molecular structures. They have been employed to make materials, pharmaceuticals, and other biologically active compounds.
“This is a very exciting day for organic chemistry,” comments Stephen L. Buchwald, a chemistry professor at Massachusetts Institute of Technology. “This is a well-deserved award that is long overdue. It is hard to overestimate the importance of these processes in modern-day synthetic chemistry. They are the most used reactions by those in the pharmaceutical industry.”
Although chemistry oddsmakers had been betting that Pd-catalyzed cross-coupling chemistry would earn the Nobel Prize for many years, Heck, 79, tells C&EN that his win was “totally unexpected.” Retired from the University of Delaware and living in the Philippines, Heck admits that he doesn’t run into chemists all that often. Nevertheless, he says, “I’m very thankful and very pleased to have received the prize.”
The pioneering chemistry discovered by Heck in 1968 uses Pd to wed an aryl halide with an olefin. “It’s turned out to be something of value to the chemistry community,” Heck says of the reaction that bears his name.
In 1977, Negishi, who is now 75 and the Herbert C. Brown Distinguished Professor of Organic Chemistry at Purdue University, used Pd to catalyze couplings of organozinc reagents with organohalides. Two years later, Suzuki, who is 80 and currently a chemistry professor at Japan’s Hokkaido University, began developing a Pd-catalyzed coupling of organoboron compounds with organohalides.
“The key word here is versatility,” said Negishi, when describing his chemistry to reporters during an early-morning phone call on the day of the announcement. “One of our dreams is to be able to synthesize any organic compound of importance, whether it is a medicinally important compound or important from the point of view of materials science.”
He likened Pd-catalyzed cross-couplings to the Grignard reaction, a carbon-carbon bond-forming reaction developed by Victor Grignard, the 1912 Nobel Laureate in Chemistry. “The Grignard reaction made possible the synthesis of a wide variety of organic compounds,” Negishi told reporters. “We came up with a totally different method that not only complements but also surpasses in versatility Grignard chemistry.”
“The award recognizes fundamental chemistry at its best,” says American Chemical Society President and Purdue University professor Joseph S. Francisco. “The beauty of this work is that these cross-couplings are very robust, very clean, very versatile, and I have to say, very elegant.”
“To practicing synthetic chemists in industry and academe, these names are familiar in the same way as are members of their own family,” adds Victor Snieckus, a chemistry professor at Queens University, in Kingston, Ontario. “Many of us have run Heck, Negishi, and Suzuki reactions with our own hands. The whole community is overjoyed and applauds these awards.”