Computational study of the mechanism of cyclometalation by palladium acetate
David L Davies1, Steven M A Donald, Stuart A Macgregor
1Department of Chemistry, University of Leicester, Leicester LE1 7RH, UK. did3@leicester.ac.uk
Journal of the American Chemical Society
|October 6, 2005
Abstract:
Various mechanisms for the cyclometalation of dimethylbenzylamine by palladium acetate have been studied by DFT calculations. Contrary to previous suggestions, the rate-limiting step is the electrophilic attack of the palladium on an ortho arene C-H bond to form an agostic complex rather than a Wheland intermediate. The cyclometalated product is then formed by intramolecular deprotonation by acetate via a six-membered transition state; this step has almost no activation barrier.
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