CLEANER FUELS
Kuo-Wei Huang (second from left) and his researchers are working on a catalytic platform that has the potential to be a game changer for catalyst chemistry.
CATALYSIS CAPTURED IN A PINCER MOVEMENT
Hydrogen-powered cars and recycling CO2 are just two of the myriad of applications that could spring from catalysts based on a new ligand platform.
6
F a l l 2 0 19
When Kuo-Wei Huang and his group made a seemingly simple chemical modification to a pincer catalyst system, they did not observe the anticipated modest alteration to the catalyst’s reactivity. Instead, they discovered totally distinct catalytic behaviors. A decade of study later, the catalytic platform discovered by the Huang group looks set to spawn a new branch of catalyst chemistry, with the potential to drive revolutionary chemical transformations. Catalysts are chemical entities that assist with the making and breaking of bonds, often with exquisite selectivity. They are used across all areas of production, from commodity chemicals to pharmaceutical manufacturing, and they underpin the manufacturing of many chemicals and materials in use today.
In most catalysts, including organometallic catalysts, where each metal ion is wrapped in a carbon-based ligand, metals are the star of the show: they are the center of catalytic reactivity where bond creation takes place. The ligand might fine tune that reactivity, but it is essentially there to provide support. However, in Huang’s new catalyst family, that situation can be reversed: the ligand can be the site of catalytic activity where new bond formation takes place, and the metal is relegated to the support role. “For the last 100 years, we have been talking about how to modify the ligand to manipulate the reactivity of the metal center,” Huang says. “Now we can also use metal coordination to change the reactivity of the organic component—and maybe reach some unprecedented reactivities that cannot be achieved otherwise,” he says.