| Abstract |
Speciation studies in aqueous solution on the interaction Of Cu2+ and Zn2+ with a series of polyaminic ligands N-naphthalen-1-ylmethyl-N -[2-[(naphthalen-1-ylmethyl)- amino]-ethyl)-ethane-l,2-diamine (LI), N-naphthalen-lylmethyl-iV-(2-\2-[(naphthalen-1-ylmethyl)-amino]-ethyl - amino]-ethyl)-ethane-l,2-diamine (L2) and N-naphthalen-1-ylmethyl-N -[2-(2-\2-[(naphthalen-1-ylmethyl)-amino] - ethylamino)-ethylamino)-ethyl]-ethane-1,2-diamine (L3) containing two naphthylmethyl groups at their termini and N-1-(2-\2-[(naphthalen-1-ylmethyl)-amino]-ethyl-amino)-ethyl)-ethane- 1,2-diamine (L4) containing just one naphthylmethyl group have been carried out at 298.1 K in 0.15 mol dm (-3) NaCl. In the case of the tetraamines L2 and L4, their coordination capabilities towards Cd2+, Ni2+, Co2+ and Pb2+ have also been considered. The stability constants follow the general Irving-Williams sequence. The steady-state fluorescence emission studies on the interaction with metal ions show that while Cu2+ produces a chelation enhancement of the quenching (CHEQ), the interaction with Zn2+ leads to a chelation enhancement of the fluorescence (CHEF). Finally, ligands L1, L2 and L3 have been successfully covalently attached to silica surfaces and some preliminary results of their emissive properties are given. |
