As we enter the 21st century with expectations for even greater
technological advances than the 20th century we should pause to consider
that our foundational technologies for production of basic materials and energy
from hydrocarbons are inherently inefficient. Today, almost all of the world's
carbon-based materials and energy are generated from the oxidative conversion
of petroleum or natural gas at lower efficiencies than possible with improved
chemistry. At the core of technologies for converting hydrocarbons is the chemistry
of the CH bonds of alkanes. As a result of the high strength of the CH bond,
current processes for converting alkane CH bonds employ high temperatures (>500oC)
that lead to excessive emissions, lower efficiencies and high costs. The development
of lower temperature (<250oC), selective, catalytic alkane CH
bond conversion chemistry could lead to a new paradigm in energy and materials
technology in the 21st century that is environmentally and economically superior
and allow the vast reserves of natural gas to be employed directly as alternative
feed stocks for fuels and chemicals.
Catalysts based on the C-H activation reaction show potential for such efficient
hydrocarbon conversion technology. We define CH activation chemistry as a reaction
between CH bonds and a species “MX” that leads to the formation
of a M-C bond, Figure 1. The key to this remarkable reaction is that the cleavage
of the CH bond proceeds in a concerted manner within the coordination sphere
of “MX”. The reaction proceeds under mild conditions and with extraordinary
selectivity because high energy intermediates such as free-radicals, carbocations
or carbanions are not involved. There are many systems known for the CH activation
reaction but only a few that can be incorporated into catalytic cycles such
as those shown in Figure 1 that generate useful products. An important focus
of our research is to design and study new homogeneous catalyst that are based
on the CH activation reaction and that can operate as shown in Figure 1.
Recent results from this research are the discovery of four novel catalyst systems
(Science 1993, Science 1998, Science 2003 and Angew. Chem. Int. Ed. 2004) that
show the highest yields reported for the direct conversion of methane to useful
products at low temperatures. The recent work reported in Science 2003 demonstrates
the first reported oxidative condensation of two methane molecules to acetic acid
in one step, without the requirement any other carbon source. The proposed reaction
mechanism, shown in Figure 2, involves the CH Activation of methane as a key step.
Efforts are underway to develop a detailed understanding of these reactions with
the objective of the improving the efficiencies and extending the chemistry of
these novel systems.
Recently, we demonstrated that the bis bidentate O-donor complex, (acac-O,O)2Ir(CH3)Py),
(acac-O,O = k2-O,O-acetylacetonate, Py
= pyridine), catalyzes the C-H activation of alkanes as well as the functionalization
of arenes via the intermolecular, anti-Markovnikov, hydroarylation of olefins
to selectively generate n-alkyl benzenes. Experimental and theoretical calculations
reveal that this O-donor, octahedral, d6, late transition metal complex
is thermally stable to air and protic media and activates the C-H bonds of alkanes
and arenes by a transition state with “oxidative addition” or “insertion”
character that could be facilitated by the p-donor
properties of the O-donor ligands. This demonstrated combination of stability
and CH bond reactivity is very attractive for developing hydrocarbon conversion
catalysts based on the CH activation reaction and it is important to determine
if this chemistry can be extended to the wide variety of known O-donor ligands
such as aryloxides, tropolones, hydroxyacetophenones, catechols, etc., Figure
3. O-donor ligands are among the largest class of known ligands and complexes
with late transition metals could lead to a broad, new class of stable, homogeneous
complexes with a unique reactivity and possibility for steric and electronic
An exciting extension of this alkane conversion research based on the CH activation
reaction will be to develop homogeneous catalysts that could provide the basis
for the next generation of fuel cells that operate with higher efficiency, reliability
and lower cost than possible today. To this end, novel homogeneous complexes
will be synthesized and studied in solution and attached to electrode surfaces
to begin defining the requirements for electrocatalysts that facilitate the
complete, reversible, low temperature, anodic oxidation of alkanes to carbon
dioxide and water, Eq 1.
Utilizing a general strategy of computer-assisted design and synthesis of new
homogeneous complexes based on mechanistic considerations, other areas of focus
of the group are the discovery and study of homogeneous catalysts for N2 fixation,
oxycarbonylation of alkanes and addition of various HX molecules (with emphasis
on HO, HS, HN and CH) to olefins. The research in our group is ideally suited
to graduate study leading to either academic or industrial careers as study
involves highly interdisciplinary, cutting-edge, basic research that is directed
at developing new reactions that could ultimately address some of the long standing
"Holy Grail" challenges in chemistry.
||"Stoichiometric Oxy Functionalization and CH Activation Studies of Cyclometalated Iridium(III) 6-Phenyl-2,2'-Bipyridine Hydrocarbyl Complexes. Young, Kenneth J. H.; Mironov, Oleg A.; Periana, Roy A. Organometallics ; 2007, 26(9), 2137-2140
||"Mechanistic Analysis of Iridium Heteroatom C-H Activation: Evidence for an Internal Electrophilic Substitution Mechanism. Oxgaard, Jonas; Tenn, William J., III; Nielsen, Robert J.; Periana, Roy A.; Goddard, William A., III. Organometallics ; 2007, 26(7), 1565-1567.
|| "Methane Activation with Rhenium Catalysts. 1. Bidentate Oxygenated Ligands. Gonzales, Jason M.; Oxgaard, Jonas; Periana, Roy A.; Goddard, William A., III.Organometallics; 2007,26(6), 1505-1511.
|| "Heterolytic CH Activation and Catalysis by an O-Donor Iridium-Hydroxo Complex. Tenn, William J., III; Young, Kenneth J. H.; Oxgaard, Jonas; Nielsen, Robert J.; Goddard, William A., III; Periana, Roy A. Organometallics; 2006, 25(21), 5173-5175.
||"Heterolytic CH Activation with a Cyclometalated Platinum(II) 6-Phenyl-4,4'-di-tert-butyl-2,2-Bipyridine Complex ".Kenneth J. H. Young, Steven K. Meier, Jason M. Gonzales, Jonas Oxgaard, William A. Goddard III, and Roy A. Periana Organometallics; (Communication ); 2006.25(20); 4734 - 4737 .
||"Facile Functionalization of a Metal Carbon Bond by O-Atom Transfer. Brian L. Conley, Somesh K. Ganesh, Jason M. Gonzales, William J. Tenn, III, Kenneth J. H. Young, Jonas Oxgaard, William A. Goddard, III, and Roy A. Periana J. Am. Chem. Soc.; 2006.128(28); 9018-9019 .
||"Carboxylic Solvents and O-Donor Ligand Effects on CH Activation by Pt(II) . Vadim R. Ziatdinov, Jonas Oxgaard, Oleg A. Mironov, Kenneth J. H. Young, William A. Goddard III, and Roy A. Periana J. Am. Chem. Soc.; 2006.128(23); 7404-7405 .
|| "Design and study of homogeneous catalysts for the selective, low temperature oxidation of hydrocarbons " , Brian L. Conley, William J. Tenn III, Kenneth J.H. Young, Somesh K. Ganesh, Steven K. Meier, Vadim R. Ziatdinov, Oleg Mirinov, Jonas Oxgaard, Jason Gonzales, William A. Goddard III and Roy A. Periana Journal of Molecular Catalysis A: Chemical,2006; 251(1-2);8-23
||"Mechanistic Investigation of Iridium-Catalyzed Hydrovinylation of Olefins Oxgaard, J.; Bhalla, G.; Periana, R. A.; Goddard, W. A., III Organometallics; (Article); 2006; 25(7); 1618-1625.
||"Transition Metal-catalyzed Oxidation of Alkanes in Handbook of C-H Transformations,Gaurav Bhalla, Oleg Mironov, Cj Jones, William J. Tenn III, Satoshi Nakamura, and Roy A. Periana Vol. 2, Gerald Dyker, Ed., 2005 Wiley-VCH, Weinheim, pp. 529-542.
||"Hydrovinylation of Olefins Catalyzed by an Iridium Complex via CH Activation " Bhalla, G.; Oxgaard, J.; Goddard, W. A., III; Periana, R. A. Organometallics; (Communication); 2005; 24(23); 5499-5502.
||"CH Activation with an O-Donor Iridium-Methoxo Complex. William J. Tenn, III, Kenneth J. H. Young, Gaurav Bhalla, Jonas Oxgaard, William A. Goddard, III, Roy A. Periana J. Am. Chem. Soc., 2005.127(41); 14172-14173 .
||"Synthesis, Structure and Reactivity of O-Donor Ir(III) Complexes: C-H Activation Studies with Benzene. Gaurav Bhalla, Xiang Yang Liu, Jonas Oxgaard, William A. Goddard, III, and Roy A. Periana J. Am. Chem. Soc., 2005.127(32); 11372-11389
||"Anti-Markovnikov Hydroarylation of Unactivated Olefins Catalyzed by a bis-Tropolonato Iridium (III) Organometallic Complex. Gaurav Bhalla, Jonas Oxgaard, William A. Goddard, III, and Roy. A. Periana. Organometallics, 2005, 24(13); 3229-3232 .
||"Homogeneous, catalytic, oxidative coupling of methane to acetic acid in one step. Periana, Roy A.; Mironov, Oleg; Taube, Doug; Bhalla, Gaurav; Jones, C. J. Topics in Catalysis 2005, 32(3-4), 169-174.
||"C-H activation of alkanes and arenes catalyzed by an O-donor bis(tropolonato)iridium(III) complex. Bhalla, Gaurav; Periana, Roy A. Angewandte Chemie, International Edition 2005, 44(10), 1540-1543.
||"Selective oxidation of methane to methanol catalyzed, with C-H activation, by homogeneous, cationic gold. Jones, C. J.; Taube, Doug; Ziatdinov, Vadim R.; Periana, Roy A.; Nielsen, Robert J.; Oxgaard, Jonas; Goddard, William A., III. Angewandte Chemie, International Edition 2004, 43(35), 4626-4629.
||"Selective oxidation of CH4 to CH3OH using the Catalytica (bpym)PtCl2 catalyst: a theoretical study. Xu, X.; Fu, G.; Goddard, W. A., III; Periana, R. A. Studies in Surface Science and Catalysis 2004, 147(Natural Gas Conversion VII), 499-504.
||"Mechanistic Analysis of Hydroarylation Catalysts Oxgaard, Jonas; Periana, Roy A.; Goddard, William A., III. Journal of the American Chemical Society 2004, 126(37), 11658-11665.
||"Alkane C-H bond activation by O-donor Ir complexes." Bhalla, Gaurav; Liu, Xiang Yang; Wong-Foy, Antek; Jones, C. J.; Periana, Roy A.. ACS Symposium Series 2004, 885(Activation and Functionalization of C-H Bonds), 105-115.
||"Perspectives on some challenges and approaches for developing the next generation of selective, low temperature, oxidation catalysts for alkane hydroxylation based on the CH activation reaction. Periana, Roy A.; Bhalla, Gaurav; Tenn, William J.; Young, Kenneth J. H.; Liu, Xiang Yang; Mironov, Oleg; Jones, Cj; Ziatdinov, Vadim R. Journal of Molecular Catalysis A: Chemical 2004, 220(1), 7-25.
||"Synthesis and Structural Characterization of Novel Organometallic, Rh(III), Bis(acetylacetonate) Complexes Liu, Xiang Yang; Tenn, William J., III; Bhalla, Gaurav; Periana, Roy A. Organometallics 2004, 23(15), 3584-3586.
||"Mechanism of Homogeneous Ir(III) Catalyzed Regioselective Arylation of Olefins. " Oxgaard, Jonas; Muller, Richard P.; Goddard, William A.; Periana, Roy A. Journal of the American Chemical Society 2004, 126(1), 352-363.
||"Alkane C-H Activation and Catalysis by an O-Donor Ligated Iridium Complex. Wong-Foy, Antek G.; Bhalla, Gaurav; Liu, Xiang Yang; Periana, Roy A. Journal of the American Chemical Society 2003, 125(47), 14292-14293.
||"Catalytic, Oxidative Condensation of CH4 to CH3COOH in One Step via CH Activation. Periana, Roy A.; Mironov, Oleg; Taube, Doug; Bhalla, Gaurav; Jones, C. J. Science (Washington, DC, United States) 2003, 301(5634), 814-818. Abstract View Full Text
||"Structure, Bonding, and Stability of a Catalytica Platinum (II) Catalyst: A Computational Study. Xu, Xin; Kua, Jeremy; Periana, Roy A.; Goddard, William A., III. Organometallics 2003, 22(10), 2057-2068.
||"Novel bis-acac-O,O-Ir(III) Catalyst for Aanti-Markovnikov, Hydroarylation of Olefins Operates by Arene CH activation. Periana, Roy A.; Liu, Xiang Y.; Bhalla, Gaurav. Chemical Communications (Cambridge, United Kingdom) 2002, (24), 3000-3001.
||"High Yield Conversion of Methane to Methyl bisulfate Catalyzed by Iodine Cations. Periana, Roy A.; Mironov, Oleg; Taube, Douglas J.; Gamble, Scott. Chemical Communications (Cambridge, United Kingdom) 2002, (20), 2376-2377.
||"Direct Synthesis of Styrene by Rhodium-catalyzed Oxidative Arylation of Ethylene with Benzene. Matsumoto, Takaya; Periana, Roy A.; Taube, Douglas J.; Yoshida, Hajime Journal of Catalysis 2002, 206(2), 272-280.
||"Regioselective Hydrophenylation of Olefins Catalyzed by an Ir(III) Complex. Matsumoto, Takaya; Periana, Roy A.; Taube, Douglas J.; Yoshida, Hajime. Journal of Molecular Catalysis A: Chemical 2002, 180(1-2), 1-18.
||"Stability and Thermodynamics of the PtCl2 Type Catalyst for Activating Methane to Methanol: A Computational Study. Kua, Jeremy; Xu, Xin; Periana, Roy A.; Goddard, William A., III. Organometallics 2002, 21(3), 511-525.
|| "Methods and Catalysts for Alkylation of Aromatic Hydrocarbons Matsumoto, Takaya; Taube, Douglas J.; Periana, Roy A. Jpn. Kokai Tokkyo Koho 2001, 11 pp.
||"Catalysis Research of Relevance to Carbon Management: Progress, Challenges, and Opportunities. Periana, R. A. et. al., Chem. Rev. 2001, 101, 953.
||"Anti-Markovnikov Olefin Arylation Catalyzed by an Iridium Complex." R. A. Periana; M . Takaya; D. J. Taube; H. Tuabe; H. Yoshida, J. Am. Chem. Soc. 2000, 122, 7414.
||"Platinum Catalysts for the High-Yield Oxidation of Methane to a Methanol Derivative", R. A. Periana, D. J. Taube, S. Gamble, H. Taube, T. Satoh and H. Fujii, Science, 1998, 280, 560.
||"A Mercury-Catalyzed, High-Yield System for the Oxidation of Methane to Methanol", R. A. Periana, D. J. Taube, E. R. Evitt, D. G. Loffler, P. R. Wentrcek, G. Voss and T. Masuda, Science 1993, 259, 340.
|| "High-Yield, Low-Temperature Oxidation of Methane to Methanol", R. A. Periana, D. J. Taube, S. Gamble, H. Taube and H. Fuji, NATO ASI Ser. 1998, Ser. 3, 44 (Catalytic Activation and Functionalization of Light Alkanes), 297-310.
||"A Computational Study of the Highly Efficient Conversion of Methane to Methanol with Mercury (II) Catalysts", Catal. Today, 1995, 23, 333.
||"A Novel, High Yield System for the Oxidation of Methane to Methanol", Studies in Surface Science and Catalysis, 1994, 81, Natural Gas Conversion II, Proceedings of the Third Natural Gas Conversion Symposium, Sydney, July 4, 1993, Elsevier.
||"A convenient asymmetric synthesis of the unnatural amino acid 2,6-dimethyl-L-tyrosine," John H. Dygos, Edward E. Yonan, Mike G. Scaros, Owen J. Goodmonson, Daniel P. Getman, Roy A. Periana, Gary R. Beck, Synthesis, 1992, 741-3.
||"C-C Activation of Organic Small Ring Compounds by the Rearrangement of Cycloalkylhydridorhodium Complexes to Rhodacyclobutanes. Synthesis of Metallacyclobutanes Including one With a Tertiary M-C Bond, by Nucleophilic Addition to p-Allyl Complexes", R. A. Periana and R. G. Bergman, J. Am. Chem. Soc. 1986, 108, 7346.
||"Isomerization of the Hydridoalkylrhodium Complexes Formed on Oxidative Addition of Rhodium to Alkane C-H Bonds. Evidence for the Intermediacy of h2-Alkane Complexes", R. A. Periana and R. G. Bergman, J. Am. Chem. Soc. 1986, 108, 7332.
||"Oxidative Addition of Soluble Iridium and Rhodium complexes to carbon-hydrogen Bonds in Methane and Higher Alkanes Janowicz, Andrew H.; Periana, Roy A.; Buchanan, J. Michael; Kovac, Carolina A.; Stryker, Jeffrey M.; Wax, Michael J.; Bergman, Robert G. Pure and Applied Chemistry 1984, 56(1), 13-23.
||"Oxidative Addition of Rhodium to Alkane C-H Bonds: Enhancement in Selectivity and Alkyl Group Functionalization", R A. Periana and R. G. Bergman, Organometallics 1984, 3, 508.
||"Rapid Intramolecular Rearrangement of a Hydrido(cyclopropyl)Rhodium Complex to a Rhodacyclobutane. Independent Synthesis of a Metallacycle by Addition of Hydride to the Central Carbon of a Cationic Rhodium p-Allyl Complex", R. A. Periana and R. G. Bergman, J. Am. Chem. Soc. 1984, 106, 7272.
||"Does substrate rather than Protein provide the catalyst for a-Proton abstraction in Aldolase?", R. A. Periana, R.Motur-Degrood, Y. Chiang, and D. J. Hupe, J. Am. Chem. Soc. 1980,102, 3923.