Two Zn(II) mononuclear coordination compounds with pyridinedicarboxylate and auxiliary N-(pyridin-4-ylmethylidene)hydroxylamine ligands.

Abstract

Two new mononuclear coordination compounds, bis{4-[(hydroxyimino)methyl]pyridinium} diaquabis(pyridine-2,5-dicarboxylato-κ(2)N,O(2))zincate(II), (C6H7N2O)2[Zn(C7H3NO4)2(H2O)2], (1), and (pyridine-2,6-dicarboxylato-κ(3)O(2),N,O(6))bis[N-(pyridin-4-ylmethylidene-κN)hydroxylamine]zinc(II), [Zn(C7H3NO4)(C6H6N2O)2], (2), have been synthesized and characterized by single-crystal X-ray diffractometry. The centrosymmetric Zn(II) cation in (1) is octahedrally coordinated by two chelating pyridine-2,5-dicarboxylate ligands and by two water molecules in a distorted octahedral geometry. In (2), the Zn(II) cation is coordinated by a tridentate pyridine-2,6-dicarboxylate dianion and by two N-(pyridin-4-ylmethylidene)hydroxylamine molecules in a distorted C2-symmetric trigonal bipyramidal coordination geometry.