4-(Dimethyl-amino)-pyridinium trans-diaqua-bis-[oxalato(2-)κ- 2 O 1,O 2]chromate(III)

Abstract

In the title salt, (C7H11N2)[Cr(C 2O4)2(H2O)2], the asymmetric unit contains one half-cation and one half-anion. The Cr atom, the C and N atoms involved in C - N(exocyclic) bonding and the N and H atoms of N - H groups lie on twofold rotation axis. The CrIII atom of the complex anion is six-coordinated in a distorted (4 + 2) octa-hedral geometry with four equatorial O atoms of two nearly coplanar oxalate and two quasi-axial aqua O atoms. In the crystal, the protonated N atoms of the pyridine rings are hydrogen bonded to the carbonyl O atoms of the anions, forming chains along [010]. These chains are connected by lateral O - H⋯O hydrogen bonds, stabilizing the structure.