The selective reaction of aryl halides with KOH: synthesis of phenols, aromatic ethers, and benzofurans.

Kevin W Anderson, Takashi Ikawa, Rachel E Tundel, Stephen L Buchwald

Index: J. Am. Chem. Soc. 128 , 10694, (2006)

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Abstract

The direct and selective synthesis of phenols from aryl/heteroaryl halides and KOH has been achieved through the use of highly active monophosphine-based catalysts derived from Pd(2)dba(3) and ligands L1 or L2 and the biphasic solvent system 1,4-dioxane/H(2)O. We have also demonstrated a one-pot method of phenol formation/alkylation for the preparation of alkyl aryl ethers from aryl halides. In many instances, this protocol overcomes limitations in existing Pd-catalyzed coupling reactions of aliphatic alcohols with aryl halides. Finally, we demonstrate that substituted benzofurans can be prepared efficiently via a Pd-catalyzed phenol formation/cyclization protocol starting from 2-chloroaryl alkynes.