Benzimidazolium halides are used for the first time as ligand precursors in ruthenium-catalyzed substitution of allylic carbonates and chlorides by carbon nucleophiles and phenols, respectively. After generation of diaminocarbene species upon deprotonation by tBuOK, their association with [Cp*Ru(MeCN)(3)]PF6 induces a very high regioselectivity in favor of the branched isomers when cinnamyl derivatives are used as starting substrates. They also provide good regioselectivities for the allylation of phenols by unsymmetrical aliphatic allylic substrates such as 3-chloro-4-phenylbut-1-ene, and thus provide a straightforward access to new allylic phenyl ethers. (c) 2005 Elsevier Ltd. All rights reserved.
C1 Inonu Univ, Fac Sci & Arts, Dept Chem, TR-44280 Malatya, Turkey.
Ege Univ, Dept Chem, TR-35100 Izmir, Turkey.
Univ Rennes 1, Inst Chim, UMR 6509, F-35042 Rennes, France.