title: Regioselective preparation of benzo[b]furans from phenols and α-bromoketones.
abstract: In this paper, a fully regiocontrolled synthesis of either 2- and 3-substituted benzo[b]furans is described. Direct reaction between phenols and α-bromoacetophenones in the presence of neutral alumina yields 2-substituted benzo[b]furans with complete regiocontrol. When a basic salt such as potassium carbonate is used, the corresponding 2-oxoether is obtained. Cyclization of these latter compounds promoted by neutral alumina yields the corresponding 3-substituted benzo[b]furans. Using the former method, Moracin M and other analogues can be obtained from commercial sources in two preparative steps. DFT calculations provide reasonable reaction paths to understand the formation of 2-substituted benzo[b]furans.
authors: Departamento de Química Orgánica I, Kimika Organikoa I Saila, Universidad del País Vasco, Euskal Herriko Unibertsitatea (UPV/EHU), Manuel de Lardizabal Etorbidea 3, 20018 San Sebastián, Donostia, Spain.
authors: Leire
authors: L
authors: Arias
authors: Yosu
authors: Y
authors: Vara
authors: Fernando P
authors: FP
authors: Cossío
mesh_terms: D001572:Benzofurans / Q000138:chemical synthesis* / Q000737:chemistry; D007659:Ketones / Q000737:chemistry*; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry*; D011789:Quantum Theory; D013237:Stereoisomerism
chemical_list: D001572:Benzofurans; D007659:Ketones; D010636:Phenols