Structurally reinforced tetraazamacrocyclic complexes

The reaction between alkyl or aryl aldehydes and macrocyclic ligands with pendant amine groups produced imidazolidine-containing bi- or tricyclic ligands. The copper complexes of three of these ligands were structurally characterized: CuL3Cl].3H2O (triclinic, P1, a = 10.041(2) A, b = 10.172(1) A, c = 11.202(1) A, alpha = 92.07(1) degrees, beta = 96.76(2) degrees, gamma = 92.99(1) degrees, Z = 2), Cu(H2L4)Cl]Cl.2H2O (monoclinic, P2(1)/n, a = 15.159(5) A, b = 10.645(1) A, c = 19.094(6) A, beta = 93.78(1) degrees, Z = 4), CuL5].2H2O.NaNO3 (monoclinic, P2(1)/n, a = 10.649(8) A, b = 7.261(2) A, c = 15.25(1) A, beta = 94.77(4) degrees, Z = 2). The conformational rigidity and stereochemical activity of these macrocycles and their complexes are discussed in comparison with close analogues.