title: A general and mild Ullmann-type synthesis of diaryl ethers.
abstract: [reaction: see text] An efficient method for the synthesis of diaryl ethers under particularly mild conditions is described. Inexpensive ligands were found to greatly accelerate the Ullmann-type coupling of aryl bromides or iodides with phenols. A series of diaryl ethers were obtained with excellent yields in acetonitrile in the presence of Cs(2)CO(3) and catalytic copper(I) oxide. The reaction tolerates substrates with unfavorable substitution patterns, such as sterically hindered coupling partners or electron-rich aryl halides.
authors.affiliation: Laboratoire de Chimie Organique (CNRS UMR 5076), Ecole Nationale Supérieure de Chimie de Montpellier, 8 rue de l'Ecole Normale, 34296 Montpellier Cedex 5, France.
authors.forename: Henri-Jean
authors.initials: HJ
authors.lastname: Cristau
authors.forename: Pascal P
authors.initials: PP
authors.lastname: Cellier
authors.forename: Samy
authors.initials: S
authors.lastname: Hamada
authors.forename: Jean-Francis
authors.initials: JF
authors.lastname: Spindler
authors.forename: Marc
authors.initials: M
authors.lastname: Taillefer