title: Synthesis of γ-benzopyranone by TfOH-promoted regioselective cyclization of o-alkynoylphenols.
abstract: Regioselective cyclization of o-alkynoylphenols forming γ-benzopyranones has been demonstrated. Trifluoromethanesulfonic acid (TfOH) induced 6-endo cyclization of o-alkynoylphenols without forming 5-exo cyclized benzofuranone derivatives to provide the corresponding γ-benzopyranones in high yields.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Tohoku University, 6-3 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8578, Japan.
authors.forename: Masahito
authors.initials: M
authors.lastname: Yoshida
authors.forename: Yuta
authors.initials: Y
authors.lastname: Fujino
authors.forename: Takayuki
authors.initials: T
authors.lastname: Doi
mesh_terms: D001578:Benzopyrans / Q000138:chemical synthesis* / Q000737:chemistry; D003500:Cyclization; D008698:Mesylates / Q000737:chemistry*; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D001578:Benzopyrans; D008698:Mesylates; D010636:Phenols; C012077:trifluoromethanesulfonic acid