title: W(CO)5(L)-catalyzed formal cope rearrangement of allenyl silyl enol ethers.
abstract: [reaction: see text] On treatment of 5-siloxyhexa-1,2,5-trienes with a catalytic amount of W(CO)(6) under photoirradiation, formal Cope rearrangement proceeded to give 2-siloxyhex-1-en-5-ynes in good yield. The electrophilic activation of the allenyl moiety by W(CO)(5) triggers the intramolecular attack of the silyl enol ether in a 6-endo manner to produce a cyclohexenyl tungsten species. Carbon-carbon bond cleavage occurs by electron donation from the anionic W(CO)(5) into the silyloxonium moiety to afford the products with regeneration of the W(CO)(5)(L).
authors.affiliation: Department of Chemistry, Tokyo Institute of Technology, Meguro-ku, Tokyo 152-8551, Japan.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Miura
authors.forename: Koichi
authors.initials: K
authors.lastname: Kiyota
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kusama
authors.forename: Nobuharu
authors.initials: N
authors.lastname: Iwasawa