Crystal structure of tris[4-(dimethylamino)pyridinium] tris(oxalato-κ²O,O′)chromate(III) tetrahydrate

Abstract

In the crystal structure of the title compound, the mol­ecular components, viz. 4-(di­methyl­amino)­pyridinium cations, tris­[oxalatochromate(III)] anions and lattice water mol­ecules, are linked through O—H⋯O and N—H⋯O hydrogen bonds into a three-dimensional network. Additional π–π inter­actions between pyridinium rings stabilize this arrangement.

Two isostructural oxalato-bridged dimetallic heptanuclear [BaII3MIII4] complexes (M = Cr; Fe) associated with 3-aminopyridinium cations: Synthesis, crystal structure and magnetic properties

“…The metathesis reaction (Equation 1), which leads to precipitation of BaC2O4, ensures the presence of only two types of ionic species (C5H7N2 + and [Ba3(H2O)5M III (C2O4)3]4 [11,14]. These reactions have been proven to be sensitive to the nature of the starting materials, the acid used for the protonation of pyridine derivatives and more importantly, to the reaction stoichiometry [22,23].…”

“…The oxalato-bridged complexes have attracted considerable attention because of their rich structural diversity and special relevance in molecular magnetism over the last few decades [8,9]. Tris(oxalato)metalate(III) hybrid salts can be prepared following a number of strategies either from a one-pot reaction [10] or by a salt metathesis-type reaction [11]. This latter approach can formally generate the desired oxalatometalate(III) salt if appropriate starting salts along with their molar ratios are chosen.…”