title: Proline-Mediated Transition Metal-Free Access to 1H-Indazolones from 2-Halobenzohydrazides.
abstract: Transition metal-free access to 1H-indazolones 1 has been achieved on the basis of base-mediated intramolecular C-N bond formation. Reactions of 2-halobenzohydrazides 2 with potassium tert-butoxide in the presence of catalytic proline provided indazolones 1 in moderate to good yields. This transformation may proceed primarily via the radical pathway according to the control experiment with a radical scavenger.
authors.affiliation: Department of Applied Biosciences, Graduate School of Life and Environmental Sciences, Osaka Prefecture University , 1-1 Gakuencho, Nakaku, Sakai, Osaka 599-8531, Japan.
authors.forename: Miho
authors.initials: M
authors.lastname: Tsujii
authors.affiliation: Department of Applied Biosciences, Graduate School of Life and Environmental Sciences, Osaka Prefecture University , 1-1 Gakuencho, Nakaku, Sakai, Osaka 599-8531, Japan.
authors.forename: Motohiro
authors.initials: M
authors.lastname: Sonoda
authors.affiliation: Department of Applied Biosciences, Graduate School of Life and Environmental Sciences, Osaka Prefecture University , 1-1 Gakuencho, Nakaku, Sakai, Osaka 599-8531, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Tanimori