Multistate Switches: Ruthenium Alkynyl-Dihydroazulene/Vinylheptafulvene Conjugates.
Multimode molecular switches incorporating distinct and independently addressable functional components have potential applications as advanced switches and logic gates for molecular electronics and memory storage devices. Herein, we describe the synthesis and characterization of four switches based on the dihydroazulene/vinylheptafulvene (DHA/VHF) photo/thermoswitch pair functionalized with the ruthenium-based Cp*(dppe)Ru ([Ru*]) metal complex (dppe=1,2-bis(diphenylphosphino)ethane; Cp*=pentamethylcyclopentadienyl). The [Ru*]-DHA conjugates can potentially exist in six different states accessible by alternation between DHA/VHF, Ru(II) /Ru(III) , and alkynyl/vinylidene, which can be individually stimulated by using light/heat, oxidation/reduction, and acid/base. Access to the full range of states was found to be strongly dependent on the electronic communication between the metal center and the organic photoswitch in these [Ru*]-DHA conjugates. Detailed electrochemical, spectroscopic (UV/Vis, IR, NMR), and X-ray crystallographic studies indeed reveal significant electronic interactions between the two moieties. When in direct conjugation, the ruthenium metal center was found to quench the photochemical ring-opening of DHA, which in one case could be restored by protonation or oxidation, allowing conversion to the VHF state.
Department of Chemistry and Center for Exploitation of Solar Energy, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark.
Alexandru
A
Vlasceanu
Department of Chemistry and Center for Exploitation of Solar Energy, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark.
Cecilie L
CL
Andersen
Department of Chemistry and Center for Exploitation of Solar Energy, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark.
Christian R
CR
Parker
Department of Chemistry and Center for Exploitation of Solar Energy, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark.
Ole
http://orcid.org/0000-0002-2080-1206
O
Hammerich
Department of Chemistry and Center for Exploitation of Solar Energy, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark.
Thorbjørn J
TJ
Morsing
Department of Chemistry and Center for Exploitation of Solar Energy, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark.
Martyn
M
Jevric
Department of Chemistry and Center for Exploitation of Solar Energy, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark.
Søren
S
Lindbaek Broman
Department of Chemistry and Center for Exploitation of Solar Energy, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark.
Anders
A
Kadziola
Department of Chemistry and Center for Exploitation of Solar Energy, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark. mbn@chem.ku.dk.
Mogens Brøndsted
http://orcid.org/0000-0001-8377-0788
MB
Nielsen
acetylides; azulenes; fulvenes; organometallic compounds; photochromism