title: Fluorescent ratiometry of tetrahomodioxacalix[4]arene pyrenylamides upon cation complexation.
abstract: [structure: see text] C-1,2-alternate tetrahomodioxacalix[4]arene pyreneamides were synthesized. Pb(2+) coordination gave a quenched monomer and excimer fluorescence emission, while upon Ca(2+) ion binding, the receptor provides an enhanced excimer and declined monomer emission with ratiometric response. The excimer emission spectra changes are rationalized by frontier molecular orbitals that the effective Py-Py interaction induces emission intensity increases upon Ca(2+) ion complexation, whereas there is no such interaction observed upon Pb(2+) binding.
authors.affiliation: Department of Chemistry, Institute of Nanosensor & Biotechnology, Dankook University, Seoul 140-714, Korea.
authors.forename: Jung Kyu
authors.initials: JK
authors.lastname: Choi
authors.forename: Areum
authors.initials: A
authors.lastname: Lee
authors.forename: Seyoung
authors.initials: S
authors.lastname: Kim
authors.forename: Sihyun
authors.initials: S
authors.lastname: Ham
authors.forename: Kwanghyun
authors.initials: K
authors.lastname: No
authors.forename: Jong Seung
authors.initials: JS
authors.lastname: Kim