title: Unraveling the Photoswitching Mechanism in Donor-Acceptor Stenhouse Adducts.
abstract: Molecular photoswitches have opened up a myriad of opportunities in applications ranging from responsive materials and control of biological function to molecular logics. Here, we show that the photoswitching mechanism of donor-acceptor Stenhouse adducts (DASA), a recently reported class of photoswitches, proceeds by photoinduced Z-E isomerization, followed by a thermal, conrotatory 4π-electrocyclization. The photogenerated intermediate is manifested by a bathochromically shifted band in the visible absorption spectrum of the DASA. The identification of the role of this intermediate reveals a key step in the photoswitching mechanism that is essential to the rational design of switching properties via structural modification.
authors.affiliation: Centre for Systems Chemistry, Stratingh Institute for Chemistry, University of Groningen , Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
authors.forename: Michael M
authors.initials: MM
authors.lastname: Lerch
authors.affiliation: Centre for Systems Chemistry, Stratingh Institute for Chemistry, University of Groningen , Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
authors.forename: Sander J
authors.initials: SJ
authors.lastname: Wezenberg
authors.affiliation: Centre for Systems Chemistry, Stratingh Institute for Chemistry, University of Groningen , Nijenborgh 4, 9747 AG, Groningen, The Netherlands.|Department of Radiology, University of Groningen , University Medical Center Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands.
authors.forename: Wiktor
authors.initials: W
authors.lastname: Szymanski
authors.affiliation: Centre for Systems Chemistry, Stratingh Institute for Chemistry, University of Groningen , Nijenborgh 4, 9747 AG, Groningen, The Netherlands.
authors.forename: Ben L
authors.initials: BL
authors.lastname: Feringa