Professor – Inorganic, Organometallic Chemistry, Catalysis
Research and/or Creative Works
Research in the Waterman group applies the synthesis of novel inorganic and organometallic systems to define new reactivity and catalysis. Students will have the opportunity to prepare and fully characterize new complexes through a variety of spectroscopic techniques (e.g., NMR, IR, UV-vis, EPR), X-ray crystallography, and analytical methods. These complexes are frequently air-sensitive, and students learn to manipulate the complexes using high-vacuum and Schlenk techniques or in a glovebox. These complexes will target the catalysis of chemically important processes such as bond-forming and selective oxidation reactions.
A key reaction in element-element bond formation is dehydrocoupling, where two molecules with element-hydrogen bonds formally exchange E-H bonds to form E-E and H-H bonds. Dehydrocoupling is a very clean and efficient reaction taking often commercially available starting materials and providing element-element bonds with hydrogen (H2) as the only byproduct. However, for many elements this reaction is not facile, and a catalyst is needed. We have found that zirconium complexes supported by triamidoamine ligands such as (N3N = N(CH2CH2NSiMe3)33-) are effective for dehydrocoupling a range of primary and secondary phosphines. Through careful mechanistic study, we have determined that this catalysis proceeds via σ-bond metathesis steps as shown to the right.
Using this knowledge we are applying this system to catalyze other element-element bond formation reactions. Using the predictive power of our sigma-bond metathesis-based mechanism, we have recently demonstrated selective P-Si and P-Ge bond formation using our zirconium catalysts, and in a simple periodic analogy, we have shown, for the first time, that catalytic dehydrocoupling of arsines is possible. Our continued efforts in this area are directed at addressing questions in molecular synthesis, materials science, and energy.
A second project involves synthesis of new phosphorus-based ligand architectures to explore catalytic reactions. One reaction we are interested in is alpha-elimination, where a low-valent main group fragment (:ERm) is extruded from an early transition-metal (LnM) center such as zirconium or niobium, as depicted in the proposed catalytic cycle shown in the figure to the right. This reaction has seen limited attention in the literature, and we seek to exploit it for bond-forming catalysis.
We are also interested in developing alternative routes to accessing low-valent main-group fragments. A recent development in this area is our preparation of a phosphaalkene by insertion of an isocyanide into a zirconium-phosphorus bond. In this reaction we take a commercial available phosphorus source, a primary phosphine, and access a phosphinidene (":PR") fragment with perfect atom economy.
Stelmach, J. P. W.; Bange, C. A.; Waterman, R. Tin-Catalyzed Hydrophopshination of Alkenes. Dalton Trans. 2016, 45, in press (main group catalysis special issue).
Bange, C. A.; Ghebreab, M. B.; Ficks, A.; Mucha, N. T.; Higham, L.; Waterman, R. Zirconium-Catalyzed Intermolecular Hydrophosphination Using a Chiral, Air-Stable Primary Phosphine. Dalton Trans. 2016, 45, 1863–1867 (phosphorus chemistry special issue).
McGrew, G. I.; Khatri, P.A.; Geiger, W. E.; Kemp, R. A.; Waterman, R. Unexpected Formal Insertion of CO2 into the C–Si Bonds of a Zinc Compound. Chem. Commun. 2015, 51, 15804–15807.
Erickson, K. A.; Stelmach, J. P. W.; Mucha, N. T.; Waterman, R. Zirconium Catalyzed Amine-Borane Dehydrocoupling and Transfer Hydrogenation. Organometallics 2015, 34, 4693–4699.
Mucha, N. T.; Waterman, R. Iridium Pincer Catalysts for Silane Dehydrocoupling: Ligand Effects on Selectivity and Activity. Organometallics 2015, 34, 3865–3872. (Hillhouse memorial issue)
Pagano, J. K.; Stelmach, J. P. W.; Waterman, R. Cobalt-Catalyzed Ammonia Borane Dehydrocoupling and Transfer Hydrogenation under Aerobic Conditions. Dalton Trans. 2015, 44, 12074-12077. (earth-abundant metals in catalysis special issue)
Baker, L. A.; Chakraverty, D.; Columbus, L.; Feig, A. L.; Jenks, W. S.; Pilarz, M.; Stains, M.; Waterman, R.; Wesemann, J. L. Cottrell Scholars Collaborative New Faculty Workshop: Professional Development for New Chemistry Faculty. J. Chem. Educ. 2014, 91, 1874-1881.
Ghebreab, M. B.; Bange, C. A.; Waterman, R. Intermolecular Zirconium-Catalyzed Hydrophosphination of Alkenes and Dienes with Primary Phosphines. J. Am. Chem. Soc. 2014, 136, 9240–9243.
Erickson, K. A., Wright, D. S., Waterman, R. Dehydrocoupling of Amine Boranes via Tin(IV) and Tin(II) Catalysts. J. Organomet. Chem., 2014, 751, 541–545. (50th anniversary special issue)
Waterman, R. δ-Bond Metathesis: A 30-Year Retrospective. Organometallics, 2013, 32, 7249–7263. (invited review)
Awards and Recognition
- 2004-2007 - Miller Institute for Basic Research in Science Research Fellowship
- 2008 - National Science Foundation CAREER Award
- 2009 - Research Corporation Cottrell Scholar Award
- 2009 - Alfred P. Sloan Foundation Research Fellowship
- 2013 - Alexander von Humboldt Research Fellowship for Experienced Researcher
- 2015 - Fellow, Royal Society of Chemistry
Areas of Expertise and/or Research
synthetic inorganic chemistry, organometallic chemistry, catalysis
- Ph.D., University of Chicago, 2004
- Postdoctoral fellowship, University of California, Berkeley, CA (Miller Research Fellow), 2004-2006
- (802) 656-0278