title: SilverCatalyzed Cascade Carboxylation and Cyclization of Trimethyl(2-methylenebut-3-yn-1-yl)silane Derivatives.
abstract: C-C bond-forming carboxylation and cyclization of trimethyl(2-methylenebut-3-yn-1-yl)silane derivatives and carbon dioxide was developed. Silver catalysts and CsF promoted the reaction to afford the corresponding 2-furanone and 2-pyrone derivatives in good-to-high yields. The structure of the 2-furanone was confirmed by single-crystal X-ray crystallography, which revealed that the geometry of the exo-olefin was that of a Z-isomer. When an aromatic ring-substituted alkyne was used, 2-furanone derivatives were selectively obtained via 5-exo-dig cyclization, whereas the reaction of alkyl-substituted alkynes produced 2-pyrone derivatives with high selectivity.
authors.affiliation: Department of Chemistry, Keio University , Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Sekine
authors.affiliation: Department of Chemistry, Keio University , Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Sadamitsu
authors.affiliation: Department of Chemistry, Keio University , Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
authors.forename: Tohru
authors.initials: T
authors.lastname: Yamada