title: Electrophilic cyclization of 2-chalcogenealkynylanisoles: versatile access to 2-chalcogen-benzo[b]furans.
abstract: An efficient synthesis of 2-chalcogen-3-substituted-benzo[b]furan compounds has been accomplished via electrophilic cyclization reaction of 2-chalcogenealkynyl anisoles using I(2), ICl, Br(2), and PhSeBr as electrophile sources. The product distributions were strongly dependent on the nature of substituents in the aromatic ring of anisole and on the chalcogen atom directly bonded to the triple bond. The 2-chalcogen-3-iodo-benzo[b]furans obtained smoothly underwent conversion to more complex structures of benzo[b]furan derivatives via palladium- or copper-catalyzed cross-coupling reaction with thiols, diphenyl diselenides, and zincates.
authors.affiliation: Laboratório de Síntese, Reatividade, Avaliação Farmacológica e Toxicológica de Organocalcogênios, CCNE, UFSM, Santa Maria, Rio Grande do Sul, Brazil 97105-900.
authors.forename: Flávia
authors.initials: F
authors.lastname: Manarin
authors.forename: Juliano A
authors.initials: JA
authors.lastname: Roehrs
authors.forename: Rafaela Mozzaquatro
authors.initials: RM
authors.lastname: Gay
authors.forename: Ricardo
authors.initials: R
authors.lastname: Brandão
authors.forename: Paulo H
authors.initials: PH
authors.lastname: Menezes
authors.forename: Cristina W
authors.initials: CW
authors.lastname: Nogueira
authors.forename: Gilson
authors.initials: G
authors.lastname: Zeni
mesh_terms: D000840:Anisoles / Q000737:chemistry*; D001572:Benzofurans / Q000138:chemical synthesis* / Q000737:chemistry; D003500:Cyclization; D015394:Molecular Structure; D013237:Stereoisomerism
chemical_list: D000840:Anisoles; D001572:Benzofurans