Reaction of Molecular Oxygen with an NHC-Coordinated Pd0 Complex: Computational Insights and Experimental Implications†
Brian V. Popp
Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA, Fax: (+1) 608-262-6143
Search for more papers by this authorJohanna E. Wendlandt
Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA, Fax: (+1) 608-262-6143
Search for more papers by this authorClark R. Landis Prof.
Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA, Fax: (+1) 608-262-6143
Search for more papers by this authorShannon S. Stahl Prof.
Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA, Fax: (+1) 608-262-6143
Search for more papers by this authorBrian V. Popp
Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA, Fax: (+1) 608-262-6143
Search for more papers by this authorJohanna E. Wendlandt
Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA, Fax: (+1) 608-262-6143
Search for more papers by this authorClark R. Landis Prof.
Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA, Fax: (+1) 608-262-6143
Search for more papers by this authorShannon S. Stahl Prof.
Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA, Fax: (+1) 608-262-6143
Search for more papers by this authorWe thank M. Konnick for providing (IMes)2Pd0. Financial support and computational resources from the following agencies and the UW Parallel Computing Center are gratefully acknowledged: NSF (CHE-0094344 and CHE-0091916), NCSA (CHE-060010T), and gifts from Intel Corporation. NHC=N-heterocyclic carbene.
Graphical Abstract
O2 activation: Computational studies of the reaction of O2 with an [(NHC)2Pd0] (NHC=N-heterocyclic carbene) complex reveal an unexpectedly small driving force for formation of a PdII(η2-O2) product. This result led to experimental demonstration of reversible O2 coordination to the (NHC)2Pd center. Computational analysis of the reaction coordinate reveals that O2 reacts with Pd0 through a stepwise mechanism involving an η1-O2 transition state.
Supporting Information
Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2007/z603667_s.pdf or from the author.
Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
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