title: Butane-1,4-diyl dications stabilized by steric factors: electrochiroptical response systems based on reversible interconversion between dihydro[5]helicene-type electron acceptors and electron-donating 1,1'-binaphthyls.
abstract: Incorporation in the dihydro[5]helicene framework prevents deprotonation of the title dications by steric factors, thus allowing their isolation as deeply colored stable salts. Based on the reversible interconversion with the electron-donating binaphthylic diolefins, they constitute a new class of electrochromic systems, in which C-C bond making/breaking is accompanied by two-electron transfer. Optically pure (R)-binaphthylic donors are interconvertible with the 1,4-dications with the R,R-configuration. The very large molar ellipticity makes it possible for them to be used as electrochiroptical response systems, by which the electrochemical input is transduced into two spectral outputs, i.e. UV-Vis and circular dichroism. Structurally related push-pull-type bis(quinonemethide)s also exhibit a similar multi-output electrochemical response.
authors.affiliation: Division of Chemistry, Graduate School of Science, Hokkaido University, Sapporo, 060-0810, Japan.
authors.forename: Eisuke
authors.initials: E
authors.lastname: Ohta
authors.forename: Hiroki
authors.initials: H
authors.lastname: Higuchi
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Kawai
authors.forename: Kenshu
authors.initials: K
authors.lastname: Fujiwara
authors.forename: Takanori
authors.initials: T
authors.lastname: Suzuki