title: Cucurbit[7]uril complexes of crown-ether derived styryl and (bis)styryl dyes.
abstract: In this paper, we report the interaction of the CB[7] molecular container with crown ether styryl and (bis)styryl dyes 1-6. The interaction of monostyryl dyes (1 and 2) with CB[7] results in the formation of 1:1 complexes where the CB[7] molecule is located on the region of the guest encompassing the pyridinium ring, C=C double bond, and a portion of the aryl ring of benzocrown ethers 1 and 2. For (bis)styryl dyes (3-5), the formation of two types of complexes with composition dye.CB[7].dye and CB[7].dye.CB[7] was confirmed by a combination of optical and electrospray ionization mass spectroscopy (ESI-MS) methods. In the case of (bis)styryl dye (6), both 2:1 and 1:1 compositions 6.CB[7].6 and CB[7].6 were formed. Complex formation is accompanied by substantial changes in the optical characteristics of the dyes and formation of long-lived excimer species. We tested the stimuli responsiveness of this system in response to metal ions. We find that the metal ions prefer to bind to the electrostatically negative ureidyl C=O portals of the CB[7] rather than with the crown ether moiety of the styryl dyes.
authors.affiliation: A. N. Nesmeyanov Institute of Organoelement Compounds of the Russian Academy of Sciences, 28 Vavilova str., Moscow, 119991 Russia. fedorova@ineos.ac.ru
authors.forename: Olga A
authors.initials: OA
authors.lastname: Fedorova
authors.forename: Ekaterina Yu
authors.initials: EY
authors.lastname: Chernikova
authors.forename: Yuri V
authors.initials: YV
authors.lastname: Fedorov
authors.forename: Elena N
authors.initials: EN
authors.lastname: Gulakova
authors.forename: Aleksander S
authors.initials: AS
authors.lastname: Peregudov
authors.forename: Konstantin A
authors.initials: KA
authors.lastname: Lyssenko
authors.forename: Gediminas
authors.initials: G
authors.lastname: Jonusauskas
authors.forename: Lyle
authors.initials: L
authors.lastname: Isaacs