Professor John P. Caradonna of Boston University is supported by the Chemical Catalysis (CAT) Program in the Division of Chemistry to investigate new oxidation processes that directly utilize dioxygen in sustainable metal-based systems that preclude non-selective free-radical chain reactions. This research develops and characterizes a family of mononuclear iron complexes that utilize dioxygen (4-5 turnovers) in the production of an iron-based reactive species that is capable of oxidizing carbon-hydrogen (C-H) bonds in the presence of sacrificial two-electron donor ligands such as -keto acids. The research focuses on two fundamentally different, although related aspects of alkane oxidation: 1) the development of a molecular-level understanding of the mechanism by which these mononuclear non-heme ferrous complexes activate dioxygen to form a metal-based oxidant, and 2) the creation of second-generation complexes that will support the general synthetic use of the formal oxygen-atom transfer reactivity of these systems. The use of iron in these catalytic systems is particularly attractive as this metal is earth-abundant and non-toxic and thus, this effort opens new avenues in inexpensive and sustainable catalytic transformations of interest to industry. Overall, the effort results in a deeper understanding of fundamental reaction chemistry and leads to the development of useful reagents for the controlled oxidation of substrates such as alkanes and arenes.
Professor Caradonna and his research group actively participate in the NSF-funded PROSTARS Program in which community college students perform research in biological/chemical oriented laboratories. His laboratory also offers research opportunities to students at the earliest level possible, and annually participates in the Boston University's High School Research Internship Program in Science and Engineering. Finally, the investigator mentors and encourages recent Ph.D. graduates whose graduate careers have shown their potential for future excellence in both chemistry teaching and research though Boston University's Postdoctoral Faculty Fellow (PFF) program. Together, the research activities and educational projects generate a wide range of experiences, depth of knowledge, environmental and industrial insights, and communications skills necessary for the development of next generation scientists with interests in sustainable chemistry.
