title: Direct transition-metal-free intramolecular arylation of phenols.
abstract: Direct transition-metal-free, base-mediated intramolecular arylation of phenols with aryl halides has been developed. In the presence of 2.5 equiv of t-BuOK in dioxane at 140 degrees C, the intramolecular cyclization of 3-(2-halobenzyloxy)phenols affords 6H-benzo[c]chromenes in high yields. This reaction proceeds by an initial formation of a benzyne intermediate followed by an aromatic sp(2) C-H functionalization (a formal C-H activation) to form the carbon-carbon bond.
authors.affiliation: Department of Chemistry, University of Houston, Houston, Texas 77204-5003, USA.
authors.forename: Gan B
authors.initials: GB
authors.lastname: Bajracharya
authors.forename: Olafs
authors.initials: O
authors.lastname: Daugulis
mesh_terms: D008670:Metals / Q000737:chemistry; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry*
chemical_list: D008670:Metals; D010636:Phenols
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