title: Complexation of Donor-Acceptor Substituted Aza-Crowns with Alkali and Alkaline Earth Metal Cations. Charge Transfer and Recoordination in Excited State.
abstract: Complexation between two aza-15-crown-5 ethers bearing electron donor and acceptor fragments and alkali and alkaline earth perchlorates has been studied using absorption, steady-state fluorescence and femtosecond transient absorption spectroscopy. The spectral-luminescent parameters, the stability and dissociation constants of the complexes were calculated. The intramolecular charge transfer reaction takes place both in the excited state of the crowns and their complexes 1:1; the latter is subjected to photorecoordination resulting in a weakening or a complete disruption of coordination bond between nitrogen atom and metal cation, disposed within a cavity of the crown. The compounds investigated can be viewed as novel optical molecular sensors for alkali and alkaline-earth metal cations. The photoejection of a metal cation into the bulk was not observed.
authors.affiliation: Chemistry Department, M. V. Lomonosov Moscow State University, 1-3 Leninskie gory, Moscow, 119991, Russia. volchkov_vv@mail.ru.
authors.forename: Valery V
authors.identifier: http://orcid.org/0000-0002-9902-076X
authors.initials: VV
authors.lastname: Volchkov
authors.affiliation: N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 4 Kosygina str., Moscow, 119991, Russia.
authors.forename: Fedor E
authors.initials: FE
authors.lastname: Gostev
authors.affiliation: N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 4 Kosygina str., Moscow, 119991, Russia.
authors.forename: Ivan V
authors.initials: IV
authors.lastname: Shelaev
authors.affiliation: Chemistry Department, M. V. Lomonosov Moscow State University, 1-3 Leninskie gory, Moscow, 119991, Russia.|N. N. Semenov Institute of Chemical Physics, Russian Academy of Sciences, 4 Kosygina str., Moscow, 119991, Russia.
authors.forename: Viktor A
authors.initials: VA
authors.lastname: Nadtochenko
authors.affiliation: Photochemistry Center, Russian Academy of Sciences, 7A-1 Novatorov str., Moscow, 119421, Russia.
authors.forename: Svetlana N
authors.initials: SN
authors.lastname: Dmitrieva
authors.affiliation: Chemistry Department, M. V. Lomonosov Moscow State University, 1-3 Leninskie gory, Moscow, 119991, Russia.|Photochemistry Center, Russian Academy of Sciences, 7A-1 Novatorov str., Moscow, 119421, Russia.
authors.forename: Sergey P
authors.initials: SP
authors.lastname: Gromov
authors.affiliation: Photochemistry Center, Russian Academy of Sciences, 7A-1 Novatorov str., Moscow, 119421, Russia.
authors.forename: Mikhail V
authors.initials: MV
authors.lastname: Alfimov
authors.affiliation: Chemistry Department, M. V. Lomonosov Moscow State University, 1-3 Leninskie gory, Moscow, 119991, Russia.
authors.forename: Mikhail Ya
authors.initials: MY
authors.lastname: Melnikov
keywords: Aza-crown ether; Complexation; Dissociation; Perchlorates; Recoordination; Transient absorption