title: Catalytic Synthesis of Saturated Oxygen Heterocycles by Hydrofunctionalization of Unactivated Olefins: Unprotected and Protected Strategies.
abstract: A mild, general, and functional group tolerant intramolecular hydroalkoxylation and hydroacyloxylation of unactivated olefins using a Co(salen) complex, an N-fluoropyridinium salt, and a disiloxane reagent is described. This reaction was carried out at room temperature and afforded five- and six-membered oxygen heterocyclic compounds, such as cyclic ethers and lactones. The Co complex was optimized for previously rare medium ring formation by hydrofunctionalization of unactivated olefins. The powerful Co catalyst system also enables the deprotective hydroalkoxylation of O-protected alkenyl alcohol and hydroacyloxylation of alkenyl ester to afford cyclic ethers and lactones directly. The substrate scope and mechanistic proof of deprotection were investigated. The experimental evidence supports the concerted transition state of the bond-forming step involving a cationic Co complex.
authors.affiliation: Faculty of Pharmacy, Musashino University , 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Shigehisa
authors.affiliation: Faculty of Pharmacy, Musashino University , 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan.
authors.forename: Miki
authors.initials: M
authors.lastname: Hayashi
authors.affiliation: Faculty of Pharmacy, Musashino University , 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan.
authors.forename: Haruna
authors.initials: H
authors.lastname: Ohkawa
authors.affiliation: Faculty of Pharmacy, Musashino University , 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Suzuki
authors.affiliation: Faculty of Pharmacy, Musashino University , 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Okayasu
authors.affiliation: Faculty of Pharmacy, Musashino University , 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan.
authors.forename: Mayumi
authors.initials: M
authors.lastname: Mukai
authors.affiliation: Faculty of Pharmacy, Musashino University , 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan.
authors.forename: Ayaka
authors.initials: A
authors.lastname: Yamazaki
authors.affiliation: Faculty of Pharmacy, Musashino University , 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan.
authors.forename: Ryohei
authors.initials: R
authors.lastname: Kawai
authors.affiliation: Faculty of Pharmacy, Musashino University , 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan.
authors.forename: Harue
authors.initials: H
authors.lastname: Kikuchi
authors.affiliation: Faculty of Pharmacy, Musashino University , 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan.
authors.forename: Yui
authors.initials: Y
authors.lastname: Satoh
authors.affiliation: Faculty of Pharmacy, Musashino University , 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan.
authors.forename: Akane
authors.initials: A
authors.lastname: Fukuyama
authors.affiliation: Faculty of Pharmacy, Musashino University , 1-1-20 Shinmachi Nishitokyo-shi, Tokyo 202-8585, Japan.
authors.forename: Kou
authors.initials: K
authors.lastname: Hiroya