Palladium-catalyzed intramolecular O-arylation of enolates: application to benzo[b]furan synthesis.

[reaction: see text] A catalyst generated from Pd2(dba)3 and the ligand DPEphos effects intramolecular C-O bond formation between enolates and aryl halides in the conversion of 1-(2-haloaryl)ketones directly into the corresponding benzofurans. Both cyclic and acyclic ketones are efficient substrates. Thio ketones can also be employed allowing the preparation of the corresponding benzothiophenes