TY - JOUR
T1 - Synthesis and H+, Cu2+, and Zn2+ coordination behavior of a bis(fluorophoric) bibrachial lariat aza-crown
AU - Clares, M. Paz
AU - Aguilar, Juan
AU - Aucejo, Ricardo
AU - Lodeiro, Carlos
AU - Albelda, M. Teresa
AU - Pina, Fernando
AU - Lima, J. C.
AU - Parola, A. Jorge
AU - Pina, João
AU - Melo, J. Seixas de
AU - Soriano, Concepción
AU - García-España, Enrique
PY - 2004/9/20
Y1 - 2004/9/20
N2 - The synthesis, protonation behavior, and Cu2+ and Zn 2+ coordination chemistry of the novel bibrachial aza lariat ether (naphthalen-1-ylmethyl)[2-(20-{2-[(naphthalen-1-ylmethyl)amino]ethyl}-3,6,9,17, 20,23,29,30-octaazatricyclo-[23.3.1.1*11,15*]triaconta-1(29),11(30), 12,14,25,27-hexaen-6-yl)ethyl]amine (L) are discussed. The macrocycle, which has two aminoethyl naphthyl moieties symmetrically appended to a 2:2 azapyridinophane structure, displays, in the pH range 2-11, six protonation steps that correspond to the protonation of the secondary amino groups. Steady-state fluorescence measurements show emissions due to the monomer and to the excimer formed between the two naphthalene fragments of the macrocycle. The time-resolved fluorescence data, obtained by the time-correlated single photon counting technique, show that a significant percentage of excimer is preformed as ground-state dimers. The ligand L forms with the metal ions Cu2+ and Zn2+ mono- and dinuclear complexes in aqueous solution. The influence of metal coordination in the fluorescence emission of L is analyzed. The acid-base, coordination capabilities, and emissive behavior of L are compared with those presented by its synthetic precursor L1, which has a tripodal tris(2-aminoethyl)amine structure functionalized at one of its terminal amino groups with a naphthyl moiety.
AB - The synthesis, protonation behavior, and Cu2+ and Zn 2+ coordination chemistry of the novel bibrachial aza lariat ether (naphthalen-1-ylmethyl)[2-(20-{2-[(naphthalen-1-ylmethyl)amino]ethyl}-3,6,9,17, 20,23,29,30-octaazatricyclo-[23.3.1.1*11,15*]triaconta-1(29),11(30), 12,14,25,27-hexaen-6-yl)ethyl]amine (L) are discussed. The macrocycle, which has two aminoethyl naphthyl moieties symmetrically appended to a 2:2 azapyridinophane structure, displays, in the pH range 2-11, six protonation steps that correspond to the protonation of the secondary amino groups. Steady-state fluorescence measurements show emissions due to the monomer and to the excimer formed between the two naphthalene fragments of the macrocycle. The time-resolved fluorescence data, obtained by the time-correlated single photon counting technique, show that a significant percentage of excimer is preformed as ground-state dimers. The ligand L forms with the metal ions Cu2+ and Zn2+ mono- and dinuclear complexes in aqueous solution. The influence of metal coordination in the fluorescence emission of L is analyzed. The acid-base, coordination capabilities, and emissive behavior of L are compared with those presented by its synthetic precursor L1, which has a tripodal tris(2-aminoethyl)amine structure functionalized at one of its terminal amino groups with a naphthyl moiety.
KW - Molecules
KW - Ligands
KW - Stability constants
UR - http://www.scopus.com/inward/record.url?scp=4644245222&partnerID=8YFLogxK
U2 - 10.1021/ic049694t
DO - 10.1021/ic049694t
M3 - Article
C2 - 15360264
AN - SCOPUS:4644245222
SN - 0020-1669
VL - 43
SP - 6114
EP - 6122
JO - Inorganic Chemistry
JF - Inorganic Chemistry
IS - 19
ER -