Syntheses And Structures Of The Coordination Complexes Based On Armed A Azacrown Ether Containing Phenol Groups

The synthesis of aza-macrocyclic compounds received considerable attention during the last decade because of their relationship to biomimetic and catalytic systems and the applications of this type of chelating agents to biology and medicine. However, N-Functionalization of these macrocycles can enhance their metal-ion selectivity and the stability of these complexes depending on the co-ordination properties of the pendant arms. In our current efforts in searching for how the functional groups effect the properties of the macrocyclic complexes. In this paper, we synthesized an aza-crown ether ligand: 12,25-dimethyl-3,8,16,21-tetraaza-tricyclo-[21.3.110,14]tetracosa-1(27), 10,12,14(28),23,25 -hexaene-27,28-diol(H2L) and its two armed derivatives H2L1and H6L2 (see below),. This article represents a systematical examination of the syntheses, structures and properties of the five new complexes generated from N-substituted aza-crown ether ligands, namely:[Co3 (L2)(H2O)2(MeOH)4] (1),[Co3(L2)(H2O)EtOH] (2),Ni3(L2)(H2O)2]·H2O (3),[Cu4(L2) H2O]MeOH·5H2O (4) and [Zn4(L2)(OAc)2]·1.5H2O (5). The compounds were characterized by IR, elemental analysis, thermogravimetric analysis (TGA), X-ray single-crystal diffraction and XRPD.By change the central metals, diverse structures were observed for these complexes. Compound 1 is a mononuclear, but the water extend the molecule to a 1D chain structure by intermolecular hydrogen bonds. The crystal structures of 2 and 3 are similar to each other being an infinite 1D chain structure, while 4 displays a novel 2D framework based on copper-oxygen clusters. Unexpectedly, compound 5 displays a different structure, which exhibits a 3D porous framework with the water molecule located in the channels.Their crystal structures and teamperatur-controlled syntheses were investigated.