title: A reverse donor-acceptor bistable [2]catenane.
abstract: A [2]catenane, composed of a pi-electron-rich bis-1,5-dioxynaphthalene[38]crown10 (BDNP38C10) ring, mechanically interlocked with a large macrocycle containing two disubstituted tetraarylmethane "speed bumps" and two different pi-electron-deficient units--namely, naphthalene dimide (NpI) and bipyridinium (BIPY(2+)) units--has been synthesized from a [2]rotaxane, containing the former recognition unit, after performing two sequential Cu(I)-catalyzed azide-alkyne cycloadditions with a linker containing the latter recognition unit. The product, which exists as a single co-conformer, wherein the BDNP38C10 ring encircles the NpI unit, undergoes equilibration to give approximately equal amounts of the other co-conformer in which the BDNP38C10 ring encircles the BIPY(2+) unit.
authors.affiliation: California NanoSystems Institute and Department of Chemistry and Biochemistry, University of California, Los Angeles, 405 Hilgard Avenue, Los Angeles, California 90095, USA.
authors.forename: Ali
authors.initials: A
authors.lastname: Coskun
authors.forename: Sourav
authors.initials: S
authors.lastname: Saha
authors.forename: Ivan
authors.initials: I
authors.lastname: Aprahamian
authors.forename: J Fraser
authors.initials: JF
authors.lastname: Stoddart