Versatile nuclearity in copper complexes with ortho functionalized 1,3-bis(aryl)triazenido ligands

The synthesis, characterization and crystal structures of three new copper complexes derived from 1,3-bis(aryl)triazenido ligands bearing either a methoxycarbonyl, methylthio or a hydroxymethyl group in the ortho position of one of the aromatic rings are reported. In addition to the coordination of the triazenido fragment, the Lewis basic groups coordinate to the copper centers to form complexes with different nuclearity: {1-[2-(methoxycarbonyl)phenyl]-3-[4-methylphenyl]}triazene and {1-[2-(methylthio)phenyl]-3-[4-methylphenyl]}triazene form stable dinuclear and tetranuclear Cu(I) complexes, respectively. Reaction of {1-[2-(hydroxymethyl)phenyl]-3-[4-methylphenyl]}triazene with either Cu(I) or Cu(II) results in a novel Cu(II) hexanuclear macrocyclic complex.