title: Unusual transposition of allenic framework in intramolecular cyclization of acetal-tethered (allenylmethyl)silanes.
abstract: Treatment of acetal-tethered (allenylmethyl)silanes, which were obtained from the corresponding 3-bromo-5-silyl-1,3-pentadienes by a Pd-catalyzed reaction with an acetal-tethered malonate, with TiCl(4) gave not only vinylcyclohexene derivatives via a standard S(E)2' pathway but also unusual allenylcyclopentane species via cyclization at the delta-position. Deuterium-labeling experiments revealed participation of a 1,2-hydride shift in a carbocation intermediate for the formation of the latter products.
authors.affiliation: Catalysis Research Center and Graduate School of Life Science, Hokkaido University, Kita-ku, Sapporo 001-0021, Japan. ogasawar@cat.hokudai.ac.jp
authors.forename: Masamichi
authors.initials: M
authors.lastname: Ogasawara
authors.forename: Atsushi
authors.initials: A
authors.lastname: Okada
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Murakami
authors.forename: Susumu
authors.initials: S
authors.lastname: Watanabe
authors.forename: Yonghui
authors.initials: Y
authors.lastname: Ge
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Takahashi