Dinuclear Complexes of a (30)Py2N4O4 Macrocyclic Ligand Containing Two Alpha, Alpha'-Bis(aminomethyl)pyridine Moieties. Comparison with Analogous 22- and 24-Membered Macrocyclic Ligands.

摘要

Synthesis of the hexaaza macrocycle L = 3,12,20,29,35,36-hexaaza -6,9,23,26-tetraoxatricyclo(29.3.1.1.(14,18))hexatriaconta- 1(34),14,16,18(36),31(35),32-hexaene(02-BISBAMP) is reported. Protonation as well as metal binding constants with Cu(II), Co(II), Ni(II), and Zn(II) are determined at 25.0 C and 0.100 M ionic strength. Mononuclear and dinuclear chelates of these metal ions are identified in all systems investigated. Mono, diprotonated and monohydroxy mononuclear complexes of 02-BISBAMP are formed with all metal ions studied. Strong tendencies toward hydroxide ion bridging between the two metal centers in the dinuclear complexes were not found except for the dinuclear Cu(II) complex. The metal ion affinities as well as the binucleating and bridging tendencies of 02-BISBAMP are compared to those of analogous ligands containing macrocyclic rings. Keywords: Dioxygen complex formation; Oxygen activation, Reprints. (AW)