title: A novel tandem [2 + 2] cycloaddition-Dieckmann condensation with ynolate anions. Efficient synthesis of substituted cycloalkenones and naphthalenes via formal [n + 1] cycloaddition.
abstract: A novel tandem [2 + 2] cycloaddition-Dieckmann condensation via ynolate anions is described. Ynolate anions are useful for the formation of reactive beta-lactone enolates via a pathway not involving the enolization of the corresponding beta-lactones. The [2 + 2] cycloaddition of ynolate anions with delta- or gamma-keto esters, followed by Dieckmann condensation, gives bicyclic beta-lactones, which are easily decarboxylated to produce synthetically useful 2,3-disubstituted cyclopentenones and cyclohexenones in one pot. This tandem reaction was applied to a novel, one-pot synthesis of highly substituted naphthalenes.
authors.affiliation: Institute for Medicinal Resources, University of Tokushima, PRESTO, Japan Science and Technology Corporation (JST), Sho-machi 1, Tokushima 770-8505, Japan. shindo@ph2.tokushima-u.ac.jp
authors.forename: M
authors.initials: M
authors.lastname: Shindo
authors.forename: Y
authors.initials: Y
authors.lastname: Sato
authors.forename: K
authors.initials: K
authors.lastname: Shishido