Synthesis, crystal structure, and some properties of 4-hydroxymethylpyridinium hexafluorosilicate

Abstract

Hexafluorosilicate with the composition (LH)2SiF6 (I), (L = 4-hydroxymethylpyridine) is isolated as the interaction product of an L methanol solution and 45% hydrofluorosilicic acid (L:H2SiF6 = 1:3). In the crystal structure of I the cations and anions are linked by NH⋯F (N⋯F of 2.809(2) Å, 2.824(2) Å) and OH⋯F (O⋯F of 2.7036(18) Å) H bonds; the geometry of the SiF62− anion is a distorted octahedron (Si–F distances 1.6780(11)-1.6877(11) Å). In the IR spectrum of I the absorption bands of the main vibrations are identified; the solubility of I in water and some organic solvents and the degree of hydrolysis of the salt in a 1⋅10–4 М aqueous solution are determined.