Bis[4-(4-pyridyl)pyridinium] (4-carboxypyridine-2,6-dicarboxylato-κ³O²,N,O⁶)(pyridine-2,4,6-tricarboxylato-κ³O²,N,O⁶)ferrate(III) trihydrate

Abstract

In the title salt, (C 10 H 9 N 2) 2 [Fe(C 8 H 2 NO 6)(C 8 H 3 NO 6)]Á3H 2 O, the Fe III atom is O,N,O 0-chelated by dianionic and trianionic ligands in a slightly distorted octahedral coordination geometry. The cations and ferrate anions are linked into a layered structure; the layers are connected through the uncoordinated water molecules into a hydrogen-bonded three-dimensional supramolecular structure. One of the uncoordinated water molecules is disordered around an inversion centre and was refined with half-occupancy for each position.

Hydrogen-Bonded Quartz-type Network of Diprotonated Tetrakis(4-pyridyl)methane Dications

“…The positive charge should be accommodated mainly at the N1 atom, which also supports the position of protonation. The N1···N2 distance in the hydrogen bond is slightly longer than those of the reported distances for pyridinium ion−pyridine hydrogen bonds, , which is likely a result of this N1···O1 interaction. As described below, the counterion plays an important role for the construction of the hydrogen-bonded network structure.…”

“…Due to its directionality and energetic favorability, the hydrogen bond is one of the most important interactions to consider for the design of crystal structures . As pyridinium ions and pyridines act as proton donors and acceptors, respectively, half-protonated polypyridine derivatives, such as monoprotonated 4,4′-bipyridine (Scheme ), are useful components of hydrogen-bonded networks . Although there are numerous reports related to network structures based on pyridinium ion−pyridine hydrogen bonds, these networks are only one-dimensional.…”