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Acta Cryst. (2009). E65, o1491    [ doi:10.1107/S160053680902042X ]

A polymorph of tetraethylammonium chloride

Y. Yan, J. T. Mague and J. P. Donahue

Abstract top

The structure of the title compound, C8H20N+·Cl-, is compared with a polymorph that was described earlier in the same space group. Differences in the conformations of the ethyl groups of the cation exist between the polymorphs. This study is given here in order to provide additional unit-cell data for use in qualitative identification of crystalline samples obtained in syntheses in which Et4N+·Cl- is either used or generated.

Comment top

Tetraethylammonium chloride, Et4N+Cl- (Scheme 1), is frequently employed in inorganic synthesis as a convenient source of soluble countercations for anionic metal species. For instance, Et4N+Cl- is added to the reaction mixture in which Na2[Fe2(mnt)4] is formed from Na2(mnt) and FeCl3 (mnt = (CN)2C2S2(2-) = maleonitriledithiolate(2-)), thereby providing a metallodithiolene product that has useful solubility in common organic solvents (McCleverty et al., 1967). In other instances, Et4N+Cl- is generated as a byproduct of synthesis, as in the preparation of [Et4N][M(OSiMe3)(bdt)2] (M = Mo or W; bdt = benzene-1,2-dithiolate(2-)) by silylation of the corresponding oxo bis(dithiolene) dianion (Lorber et al., 1998; Donahue et al., 1998). The frequency with which Et4N+Cl- is used or otherwise encountered in inorganic synthesis, and the ease with which crystalline samples may be occluded with colored impurities that obscure their identity, make desirable the availability of complete crystallographic data for this compound as a means for qualitatively identifying it and avoiding needless data collections.

White parallelpiped crystals of Et4N+Cl- grew without disorder (Fig. 1) in monoclinic space group P21/c with only one formula unit in the asymmetric unit and a Z value of 4 (Fig. 2). A view of the tetraethylammonium cation that is approximately orthogonal to a mean plane projection of the C and N atoms shows a propeller-like disposition of the ethyl groups around the central N atom (Fig. 1).

Related literature top

A polymorph with three molecules in the asymmetric unit was earlier solved in the P21/n setting of this same space group (Staples, 1999). For a discussion of crystal-growth conditions that can affect the occurrence of polymorphs, see: Hulliger (1994). For descriptions of chemistry involving tetraethylammonium chloride, see: McCleverty et al. (1967); Lorber et al. (1998); Donahue et al. (1998).

Experimental top

White parallelpiped crystals of Et4N+Cl- grew by diffusion of Et2O vapor into an acetonitrile solution under a dry, N2 atmosphere.

Refinement top

H atoms were placed in calculated positions (C—H = 0.98–0.99 Å) and included as riding contributions with isotropic displacement parameters 1.2–1.5 times those of the attached C atoms.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker 2008); data reduction: SAINT (Bruker 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b); molecular graphics: SHELXTL (Sheldrick, 2008b); software used to prepare material for publication: SHELXTL (Sheldrick, 2008b).

Figures top
[Figure 1] Fig. 1. Et4N+Cl- shown with 50% probability ellipsoids.
[Figure 2] Fig. 2. Unit cell of Et4N+Cl- in P21/c.
Tetraethylammonium chloride top
Crystal data top
C8H20N+·Cl−F(000) = 368
Mr = 165.70Dx = 1.111 Mg m−3
Monoclinic, P21/cMelting point: not measured K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 8.429 (2) ÅCell parameters from 5930 reflections
b = 8.109 (2) Åθ = 2.4–28.5°
c = 14.499 (4) ŵ = 0.32 mm−1
β = 91.378 (3)°T = 100 K
V = 990.7 (4) Å3Parallelepiped, colourless
Z = 40.20 × 0.14 × 0.12 mm
Data collection top
Bruker APEXII CCD
diffractometer		2302 independent reflections
Radiation source: fine-focus sealed tube2038 reflections with I > 2σ(I)
graphiteRint = 0.032
φ and ω scansθmax = 27.8°, θmin = 2.4°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008a)		h = −10→10
Tmin = 0.876, Tmax = 0.963k = −10→10
8314 measured reflectionsl = −18→18
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.030Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.083H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0437P)2 + 0.2706P]
where P = (Fo2 + 2Fc2)/3
2302 reflections(Δ/σ)max = 0.001
95 parametersΔρmax = 0.33 e Å−3
0 restraintsΔρmin = −0.21 e Å−3
Crystal data top
C8H20N+·Cl−V = 990.7 (4) Å3
Mr = 165.70Z = 4
Monoclinic, P21/cMo Kα radiation
a = 8.429 (2) ŵ = 0.32 mm−1
b = 8.109 (2) ÅT = 100 K
c = 14.499 (4) Å0.20 × 0.14 × 0.12 mm
β = 91.378 (3)°
Data collection top
Bruker APEXII CCD
diffractometer		2302 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008a)		2038 reflections with I > 2σ(I)
Tmin = 0.876, Tmax = 0.963Rint = 0.032
8314 measured reflectionsθmax = 27.8°
Refinement top
R[F2 > 2σ(F2)] = 0.030H-atom parameters constrained
wR(F2) = 0.083Δρmax = 0.33 e Å−3
S = 1.03Δρmin = −0.21 e Å−3
2302 reflectionsAbsolute structure: ?
95 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Special details top

Experimental. The diffraction data were collected in three sets of 606 frames (0.3 °. width in ω) at φ = 0, 120 and 240 °. A scan time of 30 sec/frame was used.

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl10.24449 (3)0.49267 (3)0.660880 (18)0.02030 (10)
N10.25555 (10)0.10663 (10)0.86208 (6)0.01401 (19)
C10.30638 (13)0.09217 (13)0.76286 (7)0.0177 (2)
H1A0.40270.02250.76100.021*
H1B0.33500.20320.74020.021*
C20.18066 (15)0.01931 (15)0.69818 (8)0.0252 (3)
H2A0.1584−0.09450.71660.038*
H2B0.21910.02030.63490.038*
H2C0.08330.08500.70120.038*
C30.19934 (13)−0.05808 (13)0.90007 (8)0.0182 (2)
H3A0.1879−0.04730.96760.022*
H3B0.0930−0.08250.87300.022*
C40.30819 (14)−0.20341 (14)0.88139 (8)0.0232 (2)
H4A0.3011−0.23210.81570.035*
H4B0.2758−0.29830.91830.035*
H4C0.4178−0.17350.89810.035*
C50.11843 (12)0.22872 (13)0.86575 (7)0.0176 (2)
H5A0.14320.32480.82650.021*
H5B0.02180.17560.83930.021*
C60.08328 (14)0.28976 (15)0.96222 (8)0.0251 (3)
H6A0.08400.19631.00510.038*
H6B−0.02130.34260.96190.038*
H6C0.16440.36970.98190.038*
C70.39616 (12)0.16349 (13)0.92106 (7)0.0167 (2)
H7A0.48060.07890.91850.020*
H7B0.36290.17200.98590.020*
C80.46431 (14)0.32803 (14)0.89185 (8)0.0243 (3)
H8A0.52080.31420.83400.036*
H8B0.53820.36840.94000.036*
H8C0.37800.40780.88270.036*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.01788 (16)0.02294 (16)0.02008 (16)−0.00039 (9)0.00052 (11)0.00271 (9)
N10.0142 (4)0.0146 (4)0.0132 (4)0.0006 (3)0.0001 (3)0.0003 (3)
C10.0206 (5)0.0200 (5)0.0125 (5)0.0022 (4)0.0023 (4)−0.0006 (4)
C20.0280 (6)0.0301 (6)0.0174 (6)0.0023 (5)−0.0054 (5)−0.0035 (4)
C30.0202 (5)0.0158 (5)0.0185 (5)−0.0023 (4)0.0002 (4)0.0027 (4)
C40.0281 (6)0.0158 (5)0.0256 (6)0.0021 (4)−0.0023 (5)0.0008 (4)
C50.0158 (5)0.0183 (5)0.0187 (5)0.0045 (4)0.0008 (4)0.0006 (4)
C60.0265 (6)0.0276 (6)0.0214 (6)0.0090 (5)0.0053 (4)−0.0007 (4)
C70.0164 (5)0.0182 (5)0.0153 (5)−0.0009 (4)−0.0029 (4)−0.0002 (4)
C80.0249 (6)0.0224 (6)0.0253 (6)−0.0062 (5)−0.0035 (5)0.0013 (4)
Geometric parameters (Å, °) top
N1—C11.5153 (13)C4—H4B0.9800
N1—C71.5165 (13)C4—H4C0.9800
N1—C51.5238 (13)C5—C61.5197 (16)
N1—C31.5246 (13)C5—H5A0.9900
C1—C21.5178 (16)C5—H5B0.9900
C1—H1A0.9900C6—H6A0.9800
C1—H1B0.9900C6—H6B0.9800
C2—H2A0.9800C6—H6C0.9800
C2—H2B0.9800C7—C81.5170 (15)
C2—H2C0.9800C7—H7A0.9900
C3—C41.5219 (15)C7—H7B0.9900
C3—H3A0.9900C8—H8A0.9800
C3—H3B0.9900C8—H8B0.9800
C4—H4A0.9800C8—H8C0.9800
C1—N1—C7108.90 (8)C3—C4—H4C109.5
C1—N1—C5108.39 (8)H4A—C4—H4C109.5
C7—N1—C5111.46 (8)H4B—C4—H4C109.5
C1—N1—C3111.88 (8)C6—C5—N1114.12 (9)
C7—N1—C3107.94 (8)C6—C5—H5A108.7
C5—N1—C3108.30 (8)N1—C5—H5A108.7
N1—C1—C2114.05 (9)C6—C5—H5B108.7
N1—C1—H1A108.7N1—C5—H5B108.7
C2—C1—H1A108.7H5A—C5—H5B107.6
N1—C1—H1B108.7C5—C6—H6A109.5
C2—C1—H1B108.7C5—C6—H6B109.5
H1A—C1—H1B107.6H6A—C6—H6B109.5
C1—C2—H2A109.5C5—C6—H6C109.5
C1—C2—H2B109.5H6A—C6—H6C109.5
H2A—C2—H2B109.5H6B—C6—H6C109.5
C1—C2—H2C109.5N1—C7—C8113.96 (8)
H2A—C2—H2C109.5N1—C7—H7A108.8
H2B—C2—H2C109.5C8—C7—H7A108.8
C4—C3—N1114.85 (9)N1—C7—H7B108.8
C4—C3—H3A108.6C8—C7—H7B108.8
N1—C3—H3A108.6H7A—C7—H7B107.7
C4—C3—H3B108.6C7—C8—H8A109.5
N1—C3—H3B108.6C7—C8—H8B109.5
H3A—C3—H3B107.5H8A—C8—H8B109.5
C3—C4—H4A109.5C7—C8—H8C109.5
C3—C4—H4B109.5H8A—C8—H8C109.5
H4A—C4—H4B109.5H8B—C8—H8C109.5
C7—N1—C1—C2174.07 (9)C1—N1—C5—C6−164.83 (9)
C5—N1—C1—C2−64.51 (11)C7—N1—C5—C6−45.00 (12)
C3—N1—C1—C254.83 (11)C3—N1—C5—C673.60 (11)
C1—N1—C3—C447.32 (11)C1—N1—C7—C858.94 (11)
C7—N1—C3—C4−72.47 (11)C5—N1—C7—C8−60.59 (11)
C5—N1—C3—C4166.71 (9)C3—N1—C7—C8−179.40 (9)
Acknowledgements top

JTM gratefully acknowledges Tulane University for support of the Tulane Crystallography Laboratory.

references
References top

Bruker (2008). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.

Bruker (2009). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.

Donahue, J. P., Goldsmith, C. R., Nadiminti, U. & Holm, R. H. (1998). J. Am. Chem. Soc. 120, 12869–12881.

Hulliger, J. (1994). Angew. Chem. Int. Ed. Engl. 33, 143–162.

Lorber, C., Donahue, J. P., Goddard, C. A., Nordlander, E. & Holm, R. H. (1998). J. Am. Chem. Soc. 120, 8102–8112.

McCleverty, J. A., Atherton, N. M., Locke, J., Wharton, E. J. & Winscom, C. J. (1967). J. Am. Chem. Soc. 89, 6082–6092.

Sheldrick, G. M. (2008a). Acta Cryst. A64, 112–122.

Sheldrick, G. M. (2008b). SADABS. University of Göttingen, Germany.

Staples, R. J. (1999). Z. Kristallogr. New Cryst. Struct. 214, 231–232.