Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 10 October 1997:
Vol. 278. no. 5336, pp. 260 - 263
DOI: 10.1126/science.278.5336.260
Prev | Table of Contents | Next

Reports

The Mechanism of a C-H Bond Activation Reaction in Room-Temperature Alkane Solution

Steven E. Bromberg, Haw Yang, Matthew C. Asplund, T. Lian, * B. K. McNamara, dagger K. T. Kotz, J. S. Yeston, M. Wilkens, H. Frei, ddagger Robert G. Bergman, ddagger C. B. Harris ddagger

Chemical reactions that break alkane carbon-hydrogen (C-H) bonds are normally carried out under conditions of high temperature and pressure because these bonds are extremely strong (~100 kilocalories per mole), but certain metal complexes can activate C-H bonds in alkane solution under the mild conditions of room temperature and pressure. Time-resolved infrared experiments probing the initial femtosecond dynamics through the nano- and microsecond kinetics to the final stable products have been used to generate a detailed picture of the C-H activation reaction. Structures of all of the intermediates involved in the reaction of Tp*Rh(CO)2 (Tp* = HB-Pz3*, Pz* = 3,5-dimethylpyrazolyl) in alkane solution have been identified and assigned, and energy barriers for each reaction step from solvation to formation of the final alkyl hydride product have been estimated from transient lifetimes.

S. E. Bromberg, H. Yang, M. C. Asplund, T. Lian, B. K. McNamara, K. T. Kotz, J. S. Yeston, M. Wilkens, R. G. Bergman, C. B. Harris, Department of Chemistry, University of California at Berkeley, and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
H. Frei, Laboratory of Chemical Biodynamics, M. S. Calvin Laboratory, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
*   Present address: Department of Chemistry, Emory University, Atlanta, GA 30322, USA.

dagger    Present address: Pacific Northwest National Laboratory, Post Office Box 999, Richland, WA 99352, USA.

ddagger    To whom correspondence should be addressed.

Read the Full Text


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Real-Time Infrared Detection of Cyanide Flip on Silver-Alumina NOx Removal Catalyst.
F. Thibault-Starzyk, E. Seguin, S. Thomas, M. Daturi, H. Arnolds, and D. A. King (2009)
Science 324, 1048-1051
   Abstract »    Full Text »    PDF »
Coordination Chemistry of Saturated Molecules Special Feature: Time-resolved infrared (TRIR) study on the formation and reactivity of organometallic methane and ethane complexes in room temperature solution.
A. J. Cowan, P. Portius, H. K. Kawanami, O. S. Jina, D. C. Grills, X.-Z. Sun, J. McMaster, and M. W. George (2007)
PNAS 104, 6933-6938
   Abstract »    Full Text »    PDF »
Coordination Chemistry of Saturated Molecules Special Feature: Structural and dynamic properties of propane coordinated to TpRh(CNR) from a confrontation between theory and experiment.
E. Clot, O. Eisenstein, and W. D. Jones (2007)
PNAS 104, 6939-6944
   Abstract »    Full Text »    PDF »
Structural Observation of the Primary Isomerization in Vision with Femtosecond-Stimulated Raman.
P. Kukura, D. W. McCamant, S. Yoon, D. B. Wandschneider, and R. A. Mathies (2005)
Science 310, 1006-1009
   Abstract »    Full Text »    PDF »
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 (1998)
Science 280, 560-564
   Abstract »    Full Text »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)