The Green Aminator
Synthesis innovator is developing greener, more efficient methods for modifying molecules
Kami L. Hull likes to build stuff. She began an undergraduate degree in theater set design but later got hooked on molecular-scale construction. “I saw the beauty in building very small scaffolds, and I thought, ‘I could apply my skills from the theater world to chemistry.’ ”
Specifically, she’s designing faster and more efficient ways to make important molecules—such as pharmaceuticals—with methods that also conserve our dwindling natural resources.
When she started her own lab at the University of Illinois, Urbana-Champaign, three years ago, Hull took a long look at a poster showing the world’s top 100 drug molecules. “More than 90% of these molecules have some sort of nitrogen atom in them,” she says. The way chemists add a nitrogen-hydrogen group across two carbon atoms—a so-called hydroamination—is very wasteful, she adds. These reactions often require many steps, an excessive amount of solvent, and reagents that aren’t environmentally friendly. Her current mission is to find green ways to install nitrogen groups in organic molecules while controlling the overall chirality, or handedness, of the molecule.
Her track record suggests she’ll be successful. As a Ph.D. student in Melanie Sanford’s group at the University of Michigan, Ann Arbor, Hull helped popularize palladium acetate as a workhorse catalyst for replacing the hydrogens in a carbon-hydrogen bond with everything from fluorine to complex carbon-ring structures. “Everyone uses this palladium catalyst so much that it has become dogma,” says David Thaisrivongs, a process chemist at Merck & Co. Now that the catalyst has become ubiquitous, “people take it for granted.”-Sarah Everts