The chelate ligands 11-R-dipyrido[3,2-a:2,3'-c]phenazine, dppz-R (R = NH2, CH3, H, COOH, NO2) and the Re(dppz-R)(CO)(3)Cl (R = NH2, COOH, NO2) complexes were synthesized and characterized by conventional techniques. The influence of the donor and acceptor properties of the R substituents on the ligand properties were studied by spectroscopic techniques such as H-1-NMR and UV-Vis. Theoretical calculations were also achieved, mainly to interpret and understand the experimental spectra.