title: Palladium(II)-catalyzed oxidative transformation of allylic alcohols and vinyl ethers into 2-alkoxytetrahydrofurans: catechol as an activator of catalyst.
abstract: [chemical reaction: see text]. A highly effective synthesis of 2-alkoxytetrahydrofurans from allylic alcohols and vinyl ethers was achieved by using catalytic amounts of Pd(OAc)2, Cu(OAc)2, and catechol (1:1:2) under O2. The use of catechol as an activator of Pd(II)-Cu(II) catalyst has been unprecedented. The 2-alkoxytetrahydrofurans are formed via oxypalladation of allylic alcohols toward vinyl ethers followed by 5-exo cyclization of the resulting oxypalladation intermediate and subsequent beta-Pd-H elimination. No 6-endo cyclization of the oxypalladation intermediate occurs.
authors.affiliation: Department of Environmental Systems Engineering, Kochi University of Technology, 185 Miyanokuchi, Tosayamada, Kochi, 782-8502, Japan.
authors.forename: Kimi
authors.initials: K
authors.lastname: Minami
authors.forename: Yasufumi
authors.initials: Y
authors.lastname: Kawamura
authors.forename: Koichi
authors.initials: K
authors.lastname: Koga
authors.forename: Takahiro
authors.initials: T
authors.lastname: Hosokawa