Crystal structure of cyclohexylammonium thiocyanate

In the title salt, C6H11NH3 +·SCN−, the cyclohexylammonium ring adopts a slightly distorted chair conformation. The ammonium group occupies an equatorial position to minimize 1,3 and 1,5 diaxial interactions. In the crystal, the components are linked by N—H⋯N and N—H⋯S hydrogen-bonding interactions, resulting in a three-dimensional network.

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 The title compound, C 6 H 11 NH 3 + .SCN -, has previously been synthesized by reacting an aqueous solution of cyclohexylamine (CHA) with ammonium thiocyanate (H 4 N + SCN -) at 85-90 °C, followed by extraction of C 6 H 11 NH 3 + .SCNwith benzene, and then recrystallization from ethanol (Mathes et al., 1948). This compound is used as an animal repellent and also as an insecticide or fungicide (Stewart, 1951). It is also a starting material for the preparation of other compounds (Baluja et al., 1960;Morrison et al., 1953;Stewart, 1951), an accelerator and activator for rubber vulcanization (Mathes et al., 1955) and an accelerator for the curing of polyepoxide-polyimine materials (Goel, 1988). It has also been used as a stationary phase for gas chromatography (Coddens et al., 1986). Nevertheless, the crystal structure of this important compound has not been determined. We report here the crystal structure of C 6 H 11 NH 3 + .SCNtogether with a new roomtemperature synthesis using a salt metathesis reaction. This is a simpler process and results in a higher yield than the one published in the literature. Furthermore, we aim to use this compound to prepare new metal complexes based on both the cyclohexylammonium cation and the thiocyanate anion.

S4. Synthesis and crystallization
The title compound, C 6 H 11 NH 3 + .SCN -, was prepared by exchanging counter ions in a salt metathesis reaction between sodium thiocyanate (NaSCN) and cyclohexylammonium chloride (C 6 H 11 NH 3 +. Cl -) in ethanolic medium, where the precipitation of sodium chloride (NaCl) is the driving force for the reaction. In typical reaction, 100 mmol of NaSCN was dissolved in 350 ml absolute ethanol, while 100 mmol C 6 H 11 NH 3 + Clwas dissolved separately in 250 ml absolute ethanol.
Combining these two solutions at room temperature resulted in white precipitate of NaCl, as confirmed by X-ray powder

Figure 1
The molecular structure of the title compound with atom labels and 50% probability displacement ellipsoids. The strong N-H···N hydrogen bond linking the cation and the anion is shown as a dashed line.

Figure 2
Crystal packing of the title compound, showing the N-H···N and N-H···S hydrogen bonding interactions (see Table 1