Dr. Christopher Bradley
Education:Ph.D., Cornell University, 2006; Postdoctoral Study, University of California, Berkeley, 2006-2008
Research Area:Inorganic Chemistry & Organometallic Chemistry
Personal Research Web Site
Principal Research Interests
- Hydrocarbon activation/functionalization
- Organometallic chemistry in water
- Small molecule activation
Research in our group combines interest in fundamental structure and reactivity studies of organometallic complexes with application of such compounds towards the discovery or improvement of valuable catalytic reactions. Students gain a firm foundation in organic and inorganic synthesis, including Schlenk, glovebox, and high vacuum techniques. A strong mechanistic background is also developed using physical inorganic techniques, through kinetic, computational, and isotopic labeling experiments. Preparation of well-defined transition metal complexes expose students to a wide range of characterization techniques, including multinuclear NMR spectroscopy and X-ray diffraction methods.
Broad research themes within the group are described below and include small molecule activation/functionalization (specifically alkanes) and atom economical or “green” chemistry promoted by transition metal catalysts.
Hydrocarbon Activation and Functionalization by Transition Metal Sandwich and Half Sandwich Complexes
Currently, society harnesses the energy of the C-C and C-H bonds of alkanes during combustion which generates significant amounts of CO2 through the breakdown of hydrocarbon chains. Though alkanes are a valuable feedstock for this process, hydrocarbons are relatively underutilized as carbon building blocks for commercial chemicals. One area of interest in the group involves the synthesis of masked forms of low electron count transition metal complexes and subsequent reactivity of these compounds with small molecules, such as hydrocarbons. Catalytic functionalization of alkanes using these complexes will also be explored.
Organometallic Catalysis in Water
Water, though usually excluded from organometallic reagents at all costs, offers several advantageous characteristics as a solvent from both a safety and environmental standpoint. Furthermore, water’s anomalous properties compared to common organic solvents (i.e. density, high dielectric constant, and high heat of formation) create a unique chemical environment.
Although transition metals are able to direct the activation of a variety of E-H bonds (where E = O, N, or C), much work remains in catalytic functionalization of C-H bonds in complex substrates, specifically those which display biological activity. We hope to develop versatile C-H activation catalysts, based on robust, water-soluble metal complexes to allow the deuteration/triteration or dehydrogenation of saturated substrates in water. Ultimately, these reactions will be extended to water soluble, biologically relevant compounds in an effort to expand current libraries and to selectively label natural products for use as tracers in biochemical pathways.
- "Selective, Catalytic Cyclohexene Oxidation using Titanium-Functionalized Silicone Nanospheres." Bradley, C. A.; McMurdo, M. J.; Tilley, T. D. J. Phys. Chem. C 2007, 111, 17570-17579.
- "Carbon-Oxygen Bond Cleavage with η9, η5-Bis(indenyl)zirconium Sandwich Complexes.” Bradley, C. A.; Veiros, L. F.; Pun, D.; Lobkovsky, E.; Keresztes, I.; Chirik, P. J. J. Am. Chem. Soc.2006, 128, 16600-16612.
- "Ligand-Induced Haptotropic Rearrangements in Bis(indenyl) Zirconium Sandwich Complexes." Bradley, C. A.; Lobkovsky, E.; Keresztes, I.; Chirik, P. J. J. Am. Chem. Soc.2005, 127, 10291-10304.
- "Zirconium Sandwich Complexes with η9 Indenyl Ligands: Well-Defined Precursors for Zirconocene-Mediated Coupling Reactions." Bradley, C. A.; Keresztes, I.; Lobkovsky, E.; Young, V. G.; Chirik, P. J. J. Am. Chem. Soc.2004, 126, 16937-16950.
- "Synthesis of a Zirconium Sandwich Complex and Crystallographic Characterization of its Adduct with Tetrahydrofuran." Bradley, C. A.; Lobkovsky, E.; Chirik, P. J. J. Am. Chem. Soc.2003,125, 8110-8111.