The selective reaction of aryl halides with KOH: synthesis of phenols, aromatic ethers, and benzofurans.
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.
Anderson
Kevin W
KW
Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
Ikawa
Takashi
T
Tundel
Rachel E
RE
Buchwald
Stephen L
SL
D001572:Benzofurans / Q000737:chemistry*; D002384:Catalysis; D004988:Ethers, Cyclic / Q000737:chemistry*; D006878:Hydroxides / Q000737:chemistry*; D008024:Ligands; D015394:Molecular Structure; D010165:Palladium / Q000737:chemistry; D010636:Phenols / Q000737:chemistry*; D017680:Potassium Compounds / Q000737:chemistry*
D001572:Benzofurans; D004988:Ethers, Cyclic; D006878:Hydroxides; D008024:Ligands; D010636:Phenols; D017680:Potassium Compounds; D010165:Palladium; C029943:potassium hydroxide