A new dioxotetraamine ligand appended with fluorenyl and its copper(II) complex. Synthesis, crystal structure and solution behavior

A new dioxotetraamine ligand 6-(9-fluorenyl)-1,4,8,11-tetraazaundecane-5,7- dione (L) and its copper(II) complex have been synthesized. Detailed studie s have been made on solution chemistry of Cu(II), Ni(II) and Co(II) complex es of the ligand by pH-potentiometric and fluorimetric titration as well as cyclic voltammetry. The coordination of Cu2+ and Ni(2+)quenches the fluore scence of fluorenyl in the ligand through an electron transfer mechanism. T he crystal structure of [Cu(H-2L)] was determined. (C) 1999 Elsevier Scienc e S.A. All rights reserved.