Supramolecular Layer Structures of Mn(II), Co(II), and Cu(II) Complexes with the 3-(1H-Benzotriazol-1-yl)propaneamide Ligand: Metal Coordination vs Hydrogen Bonding

Complexes of the functionalized ligand 3-(1H-benzotriazol-1-yl)propaneamide ("BTPA") with MnCl2, CoCl2, CuCl2, and CuBr2 have been prepared and structurally characterized. Because BTPA is an amphiphilic molecule, a remarkable separation between the polar amide groups and the nonpolar benzotriazolyl residues occurs in the crystal. While in the free ligand the molecules are linked together by N-H center dot center dot center dot O bridges, the crystal structures of the metal complexes arise from interplay between bridging metal coordination and hydrogen bonding. All compounds are aggregated to supramolecular layers in the crystal, what makes them interesting as models for organic-inorganic hybrid membranes.