title: Iodocyclization versus diiodination in the reaction of 3-alkynyl-4-methoxycoumarins with iodine: synthesis of 3-iodofuro[2,3-b]chromones.
abstract: The reaction of 3-alkynyl-4-methoxycoumarins with molecular iodine in chlorinated solvents allows access to 3-iodofurochromones in good to excellent yields as the result of a iodocyclization-demethylation process. Competitive diiodination of the coumarin acetylene moiety could be eliminated by simply performing the reactions in refluxing 1,2-dichloroethane, owing to the thermal instability of the resulting (E)-1,2-diiodoethenylcoumarins.
authors.affiliation: Université Lyon 1, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires (ICBMS, UMR 5246 du CNRS), CPE Lyon, 43 Bd du 11 Novembre 1918, 69622, Villeurbanne Cedex, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Raffa
authors.forename: Sébastien
authors.initials: S
authors.lastname: Belot
authors.forename: Geneviève
authors.initials: G
authors.lastname: Balme
authors.forename: Nuno
authors.initials: N
authors.lastname: Monteiro