Carbamoyl-Substituted N-Heterocyclic Carbene Complexes of Palladium(II): Application to Sonogashira Cross-Coupling Reactions
Robert A. Batey*, Ming Shen and Alan J. Lough
*Department of Chemistry, University of Toronto, Toronto, Ontario, Canada M5S 3H6, Email: rbateychem.utoronto.ca
R. A. Batey, M. Shen, A. J. Lough, Org. Lett., 2002, 1411-1414.
DOI: 10.1021/ol017245g (free Supporting Information)
N-Heterocyclic carbene (NHC) Pd(II) complexes are very stable and useful catalysts in C-C coupling reactions. This is the first reported use of a N-carbamoyl-substituted heterocyclic carbene in sonogashira coupling. Former application of NHC-complexes in Sonogashira reactions has not yielded promising results. The new catalyst promotes the coupling under mild conditions. The use of DMF as solvent gave excellent yields, particularly with addition of 1 mol-% PPh3.
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