Sodium tris(glycinium) bis(hexafluorosilicate) glycine trisolvate

Abstract

The title compound, Na(+) x 3C(2)H(6)NO(2)(+) x 2SiF(6)(2-) x 3C(2)H(5)NO(2), arose from an unexpected reaction of glycine and HF with the glass container. It is an unusual hybrid organic-inorganic network built up from chains of vertex-sharing NaF(4)O(2) and SiF(6) octahedra. A pair of glycinium/glycine molecules bridges the chains into a sheet via a centrosymmetric O...H...O link. The other organic species interact with the network by an extensive N-H...F hydrogen-bond network, including bifurcated and trifurcated bonds. Finally, an extremely short C-H...O interaction (H...O = 2.25 Angstrom) is seen in the crystal structure. The Na atom has site symmetry overline1.

Glycine hydrogen fluoride: Remarkable hydrogen bonding in the dimeric glycine glycinium cation

“…Since hydrofluoric acid readily reacts with the glass, we expected some other species, maybe even some crystals with the unit cell dimensions as given in [5,6]. 1 The result, however, was neither GlyÁHF, nor a crystal with the parameters given in [5,6], but the previously known species sodium tris(glycinium) bis(hexafluorosilicate) glycine trisolvate [12]. This confirms the assumption that synthesis of GlyÁHF is not possible from solutions out of glass containers.…”

“…It has also been shown that the same reaction in glass vessels does not yield glycine hydrogen fluoride, instead a reaction with the glass produces sodium tris(glycinium) bis(hexafluorosilicate) glycine trisolvate [12]. Glycine hydrogen fluoride has been structurally and spectroscopically characterized.…”

Shared Hydrogen Atom Location and Chemical Composition in Picolinic Acid and Pyridoxal Hydrochloride Derivatives Determined by X-ray Crystallography

“…Thus, the presence of acid cations such as copper or the acidic conditions generated by TFA could explain the formation of this type of crystalline networks with such an interesting load neutralization pattern. In this sense, only two works describing shared hydrogen atoms in sodium tris­(glycinium) bis­(hexafluorosilicate) glycine trisolvate and trisodium bis­(5-sulfonatosalicylate) monohydrate were published. Furthermore, neutron structures of the Helicobacter pylori 5′-methylthioadenosine nucleosidase, which catalyzes the hydrolysis of the N -ribosidic bond of a variety of adenosine-containing metabolites, have proved to have an unconventional hydrogen-bond geometry together with the presence of a shared hydrogen atom between the carboxylic acid from an aspartic acid residue (D198) and the N 7 of the adenyl moiety …”

Salts of amino acids with hexafluorosilicate anion

“…Nevertheless-as we have devoted much research on crystalline salts of various amino acids over the last years-we were surprised that the salts of amino acids with hexafluorosilicate anion have not been investigated previously. The only relevant paper is [2], where the authors obtained the crystal of sodium tris(glycinium) bis(hexafluorosilicate) glycine trisolvate when they tried to obtain glycinium fluoride in glass containers (see also [3]). …”