title: Synthesis of dimethyl gloiosiphone a by way of palladium-catalyzed domino cyclization.
abstract: The synthesis of a spiro[4.4]nonane skeleton by the palladium-catalyzed domino cyclization of a linear 7-methylene-2,10-undecadienyl acetate is described. The pi-allylpalladium intermediate underwent intramolecular alkene insertion with high intraannular diastereoselectivity, followed by intramolecular Heck-type cyclization, leading to a spiro[4.4]nonane system. Oxidation of the allylic ether moiety and transformation of the vinyl group to an exo-methylene unit provided 3, which is the known synthetic intermediate of dimethyl gloiosiphone A (2).
authors.affiliation: Department of Applied Chemistry, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo 152-8552, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Doi
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Iijima
authors.forename: Masaru
authors.initials: M
authors.lastname: Takasaki
authors.forename: Takashi
authors.initials: T
authors.lastname: Takahashi