A Mechanistic Study of Direct Activation of Allylic Alcohols in Palladium Catalyzed Amination Reactions
نویسندگان
چکیده
We here report a computational approach on the mechanism of allylicamination reactions using allyl-alcohols and amines as the substrates and phosphoramidite palladium catalyst 1a, which operates in the presence of catalytic amount of 1,3-diethylurea as a co-catalyst. DFT calculations showed a cooperative hydrogen-bonding array between the urea moiety and the hydroxyl group of the allyl alcohol, which strengthens the hydrogen bond between the O-H moiety of the coordinated allyl-alcohol and the carbonyl-moiety of the ligand. This hydrogen bond pattern facilitates the (rate-limiting) C-O oxidative addition step and leads to lower energy isomers throughout the catalytic cycle, clarifying the role of the urea-moiety.
منابع مشابه
Palladium-Catalyzed Nucleophilic Substitution of Alcohols: Mechanistic Studies and Synthetic Applications
Sawadjoon, S. 2013. Palladium-Catalyzed Nucleophilic Substitution of Alcohols. Mechanistic Studies and Synthetic Applications. Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 1092. 63 pp. Uppsala: Acta Universitatis Upsaliensis. ISBN 978-91-554-8785-0. This thesis deals with the palladium-catalyzed nucleophilic substitution of π-activated alco...
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