Prospective Graduate Students Back to the Main Page
 Take the Tour | Videos | Application Information | Request Information | Online Application | Q&A
home :: people :: faculty
Print    Email

Smaranda C. Marinescu

Gabilan Assistant Professor of Chemistry
Inorganic chemistry

B.S.,2006, California Institute of Technology
Ph.D.,2011, Massachusetts Institute of Technology
Office: LJS 365
Phone: (213) 740-6075
Fax: (213) 740-0930
Email: smarines@usc.edu
 Group Homepage


Research Focus

 

Energy harvested directly from sunlight offers a desirable approach toward fulfilling the global need for clean energy. In photosynthesis, the energy of photons is used to drive the reduction of carbon dioxide to a variety of higher energy products. This reaction is biologically important because it allows for storing of the solar energy in the form of chemical energy, which can be released later in the process of respiration. Collecting and storing solar energy in chemical bonds, as nature accomplishes through photosynthesis, is a highly appealing strategy to solving the energy challenge. The two reactions considered most often in the context of artificial photosynthesis are the reduction of carbon dioxide and water. Carbon dioxide has received attention as an abundant, economical, and renewable C1 feedstock. The catalytic conversion of carbon dioxide to liquid fuels would positively impact the global CO2 balance.

Our research will focus on the design, synthesis, and study of inorganic materials for applications to solar energy conversion. Nature uses metalloproteins to perform difficult reactions, such as the reduction of carbon dioxide or water, near the thermodynamic potential and with high turnover frequencies. With inspiration from the biological systems, we will develop synthetic homogeneous catalysts that involve hydrogen bonding networks or hetero-bimetallic species capable of small molecule activation, and multiple proton and electron transfers. These synthetic systems will be employed for the reduction of carbon dioxide. Our program will also focus on the development of catalytic surfaces that will support homogeneous and heterogeneous catalysts for the activation of small molecules, such as water or carbon dioxide.

Researchers in the Marinescu group will become experts in the synthesis and characterization of organic and inorganic species. Glove-boxes and Schlenk-lines will be routinely utilized for the synthesis and handling of air- and moisture-sensitive compounds. The characterization tools for the prepared complexes include NMR, IR, EPR, UV-VIS spectroscopy and X-ray crystallography. The redox properties and catalytic activity of these species will be investigated by electrochemistry. The new electrode materials generated will be characterized by a variety of surface characterization techniques including SEM, TEM, XPS, and AFM.

The novel metal complexes and materials synthesized in the Marinescu group are expected to provide solutions to challenges related to solar energy conversion.

Selected publications

 

  1. Marinescu, S. C.; Winkler, J. R.; Gray, H. B. "Molecular Mechanisms of Cobalt Catalyzed Hydrogen Evolution" Proc. Natl. Acad. Sci. USA 2012, 109, 15127-15131.
    • This article was featured in Science (Yeston, J. S. "Protons coming and going" Science 2012, 338, 17), C&E News (Jacoby, M. "Pinning down a Cobalt-Catalyzed Hydrogen Evolution" C&E News 2012, 90, 37, 8) and a Caltech press release entitled "Showing the Way to Improved Water-Splitting Catalysts".
  2. Marinescu, S. C.; Bracher, P. J.; Winkler, J. R.; Gray, H. B. "Solar Fuels" AIP Conf. Proceedings 2013, in press.
  3. Keith, J. A.; Behenna, D. C.; Sherden, N.; Mohr, J. T.; Ma, S.; Marinescu, S. C.; Nielsen, R. J.; Oxgaard, J.; Stoltz, B. M.; Goddard, W. A., III "The Reaction Mechanism of the Enantioselective Tsuji Allylation: Inner-Sphere and Outer-Sphere Pathways, Internal Rearrangements, and Asymmetric C-C Bond Formation" J. Am. Chem. Soc. 2012, 134, 19050-19060.
  4. Marinescu, S. C.; Ng, V. W. L.; Lichtscheidl, A. G.; Schrock, R. R.; Müller, P.; Takase, M. K. "Syntheses of Variations of Stereogenic-at-Metal Imido Alkylidene Complexes of Molybdenum" Organometallics 2012, 31, 6336-6343.
  5. Behenna, D. C.; Mohr, J. T.; Sherden, N. H.; Marinescu, S. C.; Harned, A. M.; Tani, K.; Seto, M.; Ma, S.; Novák, Z.; Krout, M. R.; McFadden, R. M.; Roizen, J. L.; Enquist, J. A., Jr.; White, D. E.; Levine, S. R.; Petrova, K. V.; Iwashita, A.; Virgil, S. C.; Stoltz, B. M. "Enantioselective Decarboxylative Alkylation Reactions: Catalyst Development, Substrate Scope, and Mechanistic Studies" Chem. Eur. J. 2011, 17, 14199-14223.
  6. Marinescu, S. C.; Levine, D. S.; Zhao, Y.; Schrock, R. R.; Hoveyda, A. H. "Isolation of Pure Disubstituted E Olefins through Mo-Catalyzed Z-Selective Ethenolysis of Stereoisomeric Mixtures" J. Am. Chem. Soc. 2011, 133, 11512-11514.
  7. Marinescu, S. C.; Schrock, R. R.; Müller, P.; Takase, M. K.; Hoveyda, A. H. "Room Temperature Z-Selective Homcoupling of α-Olefins by Tungsten Catalysts" Organometallics 2011, 30, 1780-1782.
  8. Marinescu, S. C.; King, A. J.; Schrock, R. R.; Singh, R.; Müller, P.; Takase, M. K. "Simple Molybdenum(IV) Olefin Complexes of the Type Mo(NR)(X)(Y)(olefin)" Organometallics 2010, 29, 6816-6828.
  9. Schrock, R. R.; Jiang, A. J.; Marinescu, S. C.; Simpson, J. H.; Müller, P. "Fundamental Studies of Molybdenum and Tungsten Methylidene and Metallacyclobutane Complexes" Organometallics 2010, 29, 5241-5251.
  10. Marinescu, S. C.; Schrock, R. R.; Müller, P.; Hoveyda, A. H. "Ethenolysis Reactions Catalyzed by Imido Alkylidene Monopyrrolide (MAP) Complexes of Molybdenum" J. Am. Chem. Soc. 2009, 131, 10840-10841.
  11. Rendon, N.; Berthoud, R.; Blanc, F.; Gajan, D.; Maishal, T.; Basset, J.-M.; Copéret, C.; Lesage, A.; Emsley, L.; Marinescu, S. C.; Singh, R.; Schrock, R. R. "Well-Defined Silica-Supported Mo-Alkylidene Catalyst Precursors containing one OR Substituent: Methods of Preparation and Structure-Reactivity Relationship in Alkene Metathesis" Chem. Eur. J. 2009, 15, 5083-5089.
  12. Marinescu, S. C.; Schrock, R. R.; Li, B.; Hoveyda, A. H. "Inversion of Configuration at the Metal in Diastereomeric Imido Alkylidene Monoaryloxide Monopyrrolide Complexes of Molybdenum" J. Am. Chem. Soc. 2009, 131, 58-59.
  13. Marinescu, S. C.; Singh, R.; Hock, A. S.; Wampler, K. M.; Schrock, R. R.; Müller, P. "Syntheses and Structures of Molybdenum Imido Alkylidene Pyrrolide and Indolide Complexes" Organometallics 2008, 27, 6570-6578.
  14. Marinescu, S. C.; Toyoki, N.; Mohr, J. T.; Stoltz, B. M. "Homogeneous Pd-Catalyzed Enantioselective Decarboxylative Protonation" Org. Lett. 2008, 10, 1039-1042.
  15. Keith, J. A.; Behenna, D. C.; Mohr, J. T.; Ma, S.; Marinescu, S. C.; Oxgaard, J.; Stoltz, B. M.; Goddard, W. A., III "The Inner-Sphere Process in the Enantioselective Tsuji Allylation Reaction with (S)-t-Bu-phosphinooxazoline Ligands" J. Am. Chem. Soc. 2007, 129, 11876-11877.
  16. Marinescu, S. C.; Agapie, T.; Day, M. W.; Bercaw, J. E. "Group 3 Dialkyl Complexes with Tetradentate (L, L, N, O; L = N, O, S) Monoanionic Ligands - Synthesis and Reactivity" Organometallics 2007, 26, 1178-1190.
 

Chemistry Dept., USC College of Letters, Arts & Sciences