title: Construction of methylenecycloheptane frameworks through 7-exo-dig cyclization of acetylenic silyl enol ethers catalyzed by triethynylphosphine-gold complex.
abstract: A cationic gold(I) complex bearing a semihollow-shaped triethynylphosphine ligand efficiently catalyzed the 7-exo-dig cyclization of silyl enol ethers with an ω-alkynic substituent. The reaction gave various methylenecycloheptane derivatives with an exo- or endocyclic carbonyl group. The protocol was applicable not only to cyclic substrates that form bicyclic frameworks but also to acyclic ones with or without substituents in a carbon chain tether.
authors.affiliation: Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan.
authors.forename: Hideto
authors.initials: H
authors.lastname: Ito
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Ohmiya
authors.forename: Masaya
authors.initials: M
authors.lastname: Sawamura