title: A bis(heptafulvenyl)-dicyanoethylene thermoswitch with two sites for ring closure.
abstract: Suitably functionalized vinylheptafulvenes (VHFs) act as thermoswitches undergoing ring closure to the corresponding dihydroazulenes (DHAs). Here we present the synthesis of a new such thermoswitch incorporating two heptafulvene rings on a dicyanoethylene unit. The synthetic protocol explores both the tropylium species as an electrophile and as a leaving group in the generation of the heptafulvene units. The thermally induced ring closure was enhanced as a result of two accessible sites for the reaction to occur.
authors.affiliation: Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark.
authors.forename: Søren Lindbæk
authors.initials: SL
authors.lastname: Broman
authors.forename: Anne Ugleholdt
authors.initials: AU
authors.lastname: Petersen
authors.forename: Christian Gregers
authors.initials: CG
authors.lastname: Tortzen
authors.forename: Johan
authors.initials: J
authors.lastname: Vibenholt
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Bond
authors.forename: Mogens Brøndsted
authors.initials: MB
authors.lastname: Nielsen
mesh_terms: D003485:Cyanates / Q000737:chemistry*; D005030:Ethylenes / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure
chemical_list: D003485:Cyanates; D005030:Ethylenes; C036216:ethylene