Hydrogen-Bonding Networks in a Bipodal Acyl-thiourea and Its NiII 2:2 Metallamacrocyclic Complex

The crystal structures of 3,3,3‘,3‘-tetra(2-hydroxyethyl)-1,1‘-isophthaloylbis(thiourea) ( 1 ) and its green metallamacrocyclic complex cis -[Ni(L- S, O )(pyridine) 2 ] 2 ( 2 ) are reported in the context of their supramolecular behavior dictated by the use of hydrogen-bonding end-groups on the ligand. In 1, each molecule forms a junction between two 4-fold chiral helices formed by the hydrogen bonding of hydroxyl moieties and sulfur atoms. The structure of 2 is laminar, consisting of layers of water-linked metallamacrocyclic cis -[Ni(L- S, O )(pyridine) 2 ] 2 units separated by layers of pyridine guest molecules. Thermogravimetric analysis of 2 shows that on heating the guest pyridine and water molecules are released at ca. 60 °C, followed quickly by the further release of coordinated pyridines from cis -[Ni(L- S, O )(pyridine) 2 ] 2 to yield cis -[Ni(L- S, O )] 2 .