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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 71| Part 12| December 2015| Page o916
https://doi.org/10.1107/S2056989015020678

Crystal structure of (eth­­oxy­ethyl­­idene)di­methyl­aza­nium ethyl sulfate

Ioannis Tiritiris,a Stefan Saura and Willi Kantlehnera*

aFakultät Chemie/Organische Chemie, Hochschule Aalen, Beethovenstrasse 1, D-73430 Aalen, Germany
*Correspondence e-mail: willi.kantlehner@hs-aalen.de

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 10 October 2015; accepted 31 October 2015; online 7 November 2015)

In the title salt, C6H14NO+·C2H5SO4−, the C—N bond lengths in the cation are 1.2981 (14), 1.4658 (14) and 1.4707 (15) Å, indicating double- and single-bond character, respectively. The C—O bond length of 1.3157 (13) Å shows double-bond character, indicating charge delocalization within the NCO plane of the iminium ion. In the crystal, C—H⋯O hydrogen bonds between H atoms of the cations and O atoms of neighbouring ethyl sulfate anions are present, generating a three-dimensional network.

CCDC reference: 1434493

Similar articles

1. Related literature

For the crystal structure of L-argininium ethyl sulfate, see: Karapetyan (2008[Karapetyan, H. A. (2008). Acta Cryst. E64, o1982.]). For the crystal structure of (meth­oxy­methyl­idene)di­methyl­aza­nium tetra­phenyl­borate aceto­nitrile monosolvate, see: Tiritiris et al. (2014a[Tiritiris, I., Saur, S. & Kantlehner, W. (2014a). Acta Cryst. E70, o333.]). For the crystal structure of (but­oxy­methyl­idene)di­methyl­aza­nium tetra­phenyl­borate aceto­nitrile monosolvate, see: Tiritiris et al. (2014b[Tiritiris, I., Saur, S. & Kantlehner, W. (2014b). Acta Cryst. E70, o459.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C6H14NO+·C2H5O4S−

  • Mr = 241.30

  • Monoclinic, P 21 /c

  • a = 13.3979 (8) Å

  • b = 7.2860 (4) Å

  • c = 12.5284 (8) Å

  • β = 97.712 (3)°

  • V = 1211.92 (13) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.27 mm−1

  • T = 100 K

  • 0.28 × 0.22 × 0.05 mm

2.2. Data collection

  • Bruker Kappa APEXII DUO diffractometer

  • Absorption correction: multi-scan (Blessing, 1995[Blessing, R. H. (1995). Acta Cryst. A51, 33-38.]) Tmin = 0.704, Tmax = 0.746

  • 25216 measured reflections

  • 3734 independent reflections

  • 3142 reflections with I > 2σ(I)

  • Rint = 0.028

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.032

  • wR(F2) = 0.091

  • S = 1.05

  • 3737 reflections

  • 142 parameters

  • H-atom parameters constrained

  • Δρmax = 0.37 e Å−3

  • Δρmin = −0.42 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C5—H5B⋯O5i 0.98 2.32 3.288 (2) 170
C2—H2A⋯O3ii 0.98 2.40 3.341 (2) 161
C3—H3A⋯O5 0.99 2.50 3.121 (2) 120
C5—H5A⋯O2iii 0.98 2.51 3.372 (2) 147
C6—H6B⋯O5i 0.98 2.54 3.453 (2) 154
C4—H4B⋯O2iv 0.98 2.55 3.452 (2) 154
Symmetry codes: (i) x, y+1, z; (ii) [-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) [x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (iv) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: DIAMOND (Brandenburg & Putz, 2005[Brandenburg, K. & Putz, H. (2005). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXL97.

Supporting information

CCDC reference: 1434493

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S2056989015020678/hb7521sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015020678/hb7521Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2056989015020678/hb7521Isup3.cml

checkCIF report


Comment top

The cation in the title compound is similar to the cations in the structurally known compounds (methoxymethylidene)dimethylazanium tetraphenylborate acetonitrile monosolvate (Tiritiris et al., 2014a) and (butoxymethylidene)dimethylazanium tetraphenylborate acetonitrile monosolvate (Tiritiris et al., 2014b). According to the structure analysis, the C5–N1 bond length is 1.4658 (14) Å, C6–N1 = 1.4707 (15) Å and C1–N1 = 1.2981 (14) Å, showing single and double bond character, respectively. The C–N1–C angles are: 116.88 (9)° (C5–N1–C6), 120.66 (10)° (C1–N1–C5) and 122.44 (10)° (C1–N1–C6), which indicates a nearly trigonal-planar surrounding of the nitrogen centre by the carbon atoms (Fig. 1). The C–O bond length shows with 1.3157 (13) Å double bond character. The positive charge is completely delocalized on the plane formed by the atoms N1, C1 and O1 (Fig. 1). The bond lengths and angles in the ethyl sulfate ion are in good agreement with the data from the crystal structure analysis of L-argininium ethyl sulfate (Karapetyan, 2008). In the crystal structure, C—H···O hydrogen bonds between H atoms of cations and oxygen atoms of neighboring ethyl sulfate ions are present [d(H···O) = 2.32–2.55 Å] (Tab. 1), generating a three-dimensional network (Fig. 2).

Related literature top

For the crystal structure of L-argininium ethyl sulfate, see: Karapetyan (2008). For the crystal structure of (methoxymethylidene)dimethylazanium tetraphenylborate acetonitrile monosolvate, see: Tiritiris et al. (2014a). For the crystal structure of (butoxymethylidene)dimethylazanium tetraphenylborate acetonitrile monosolvate, see: Tiritiris et al. (2014b).

Experimental top

The title compound was obtained by reacting equimolar amounts of N,N-dimethylacetamide with diethyl sulfate at room temperature forming (ethoxyethylidene)dimethylazanium ethyl sulfate in nearly quantitative yield. The title compound crystallized after prolonged stay for several years at 273 K, forming colorless single crystals suitable for X-ray analysis.

Diethyl sulfate is carcinogenic, mutagenic and highly poisonous. During the use appropriate precautions must be taken.

Refinement top

The hydrogen atoms of the methyl groups were allowed to rotate with a fixed angle around the C–N and C–C bonds to best fit the experimental electron density, with Uiso(H) set to 1.5Ueq(C) and d(C—H) = 0.98 Å. The H atoms in CH2 groups were placed in calculated positions with d(C—H) = 0.99 Å and refined using riding model, with U(H) set to 1.2 Ueq(C).

Structure description top

The cation in the title compound is similar to the cations in the structurally known compounds (methoxymethylidene)dimethylazanium tetraphenylborate acetonitrile monosolvate (Tiritiris et al., 2014a) and (butoxymethylidene)dimethylazanium tetraphenylborate acetonitrile monosolvate (Tiritiris et al., 2014b). According to the structure analysis, the C5–N1 bond length is 1.4658 (14) Å, C6–N1 = 1.4707 (15) Å and C1–N1 = 1.2981 (14) Å, showing single and double bond character, respectively. The C–N1–C angles are: 116.88 (9)° (C5–N1–C6), 120.66 (10)° (C1–N1–C5) and 122.44 (10)° (C1–N1–C6), which indicates a nearly trigonal-planar surrounding of the nitrogen centre by the carbon atoms (Fig. 1). The C–O bond length shows with 1.3157 (13) Å double bond character. The positive charge is completely delocalized on the plane formed by the atoms N1, C1 and O1 (Fig. 1). The bond lengths and angles in the ethyl sulfate ion are in good agreement with the data from the crystal structure analysis of L-argininium ethyl sulfate (Karapetyan, 2008). In the crystal structure, C—H···O hydrogen bonds between H atoms of cations and oxygen atoms of neighboring ethyl sulfate ions are present [d(H···O) = 2.32–2.55 Å] (Tab. 1), generating a three-dimensional network (Fig. 2).

For the crystal structure of L-argininium ethyl sulfate, see: Karapetyan (2008). For the crystal structure of (methoxymethylidene)dimethylazanium tetraphenylborate acetonitrile monosolvate, see: Tiritiris et al. (2014a). For the crystal structure of (butoxymethylidene)dimethylazanium tetraphenylborate acetonitrile monosolvate, see: Tiritiris et al. (2014b).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The structure of the title compound with displacement ellipsoids at the 50% probability level.
[Figure 2] Fig. 2. C—H···O hydrogen bonds (black dashed lines) between H atoms of the cations and oxygen atoms of the ethyl sulfate ions (ac view).
(Ethoxyethylidene)dimethylazanium ethyl sulfate top
Crystal data top
C6H14NO+·C2H5O4S−F(000) = 520
Mr = 241.30Dx = 1.322 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3142 reflections
a = 13.3979 (8) Åθ = 1.5–30.7°
b = 7.2860 (4) ŵ = 0.27 mm−1
c = 12.5284 (8) ÅT = 100 K
β = 97.712 (3)°Plate, colorless
V = 1211.92 (13) Å30.28 × 0.22 × 0.05 mm
Z = 4
Data collection top
Bruker Kappa APEXII DUO
diffractometer		3734 independent reflections
Radiation source: fine-focus sealed tube3142 reflections with I > 2σ(I)
Triumph monochromatorRint = 0.028
φ scans and ω scansθmax = 30.7°, θmin = 1.5°
Absorption correction: multi-scan
(Blessing, 1995)		h = −18→19
Tmin = 0.704, Tmax = 0.746k = −10→10
25216 measured reflectionsl = −17→17
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.032H-atom parameters constrained
wR(F2) = 0.091 w = 1/[σ2(Fo2) + (0.0453P)2 + 0.4489P]
where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max < 0.001
3737 reflectionsΔρmax = 0.37 e Å−3
142 parametersΔρmin = −0.42 e Å−3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0079 (12)
Crystal data top
C6H14NO+·C2H5O4S−V = 1211.92 (13) Å3
Mr = 241.30Z = 4
Monoclinic, P21/cMo Kα radiation
a = 13.3979 (8) ŵ = 0.27 mm−1
b = 7.2860 (4) ÅT = 100 K
c = 12.5284 (8) Å0.28 × 0.22 × 0.05 mm
β = 97.712 (3)°
Data collection top
Bruker Kappa APEXII DUO
diffractometer		3734 independent reflections
Absorption correction: multi-scan
(Blessing, 1995)		3142 reflections with I > 2σ(I)
Tmin = 0.704, Tmax = 0.746Rint = 0.028
25216 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0320 restraints
wR(F2) = 0.091H-atom parameters constrained
S = 1.05Δρmax = 0.37 e Å−3
3737 reflectionsΔρmin = −0.42 e Å−3
142 parameters
Special details top

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
O10.26034 (6)0.67627 (11)0.47160 (7)0.01926 (17)
N10.17582 (7)0.90509 (13)0.38585 (8)0.01829 (19)
C10.17248 (8)0.74789 (15)0.43400 (9)0.0176 (2)
C20.07696 (9)0.65143 (17)0.44583 (10)0.0231 (2)
H2A0.02000.73460.42570.035*
H2B0.07780.61260.52080.035*
H2C0.07000.54350.39870.035*
C30.26376 (9)0.50086 (15)0.52879 (10)0.0216 (2)
H3A0.21950.40990.48710.026*
H3B0.24110.51650.60030.026*
C40.37134 (10)0.43818 (17)0.54103 (11)0.0272 (3)
H4A0.39200.42000.46970.041*
H4B0.37790.32220.58100.041*
H4C0.41440.53130.58040.041*
C50.27260 (9)0.99326 (15)0.37648 (10)0.0208 (2)
H5A0.31261.00100.44780.031*
H5B0.26071.11700.34680.031*
H5C0.30920.92070.32850.031*
C60.08461 (9)1.00066 (18)0.33605 (11)0.0276 (3)
H6A0.04630.91980.28300.041*
H6B0.10381.11220.30010.041*
H6C0.04301.03360.39180.041*
S10.19729 (2)0.47672 (4)0.17775 (2)0.01768 (8)
O20.31092 (6)0.47791 (12)0.14749 (7)0.02197 (18)
O30.14783 (7)0.35675 (14)0.09598 (8)0.0313 (2)
O40.16386 (7)0.66526 (12)0.17017 (8)0.02607 (19)
O50.20491 (8)0.40445 (13)0.28581 (8)0.0308 (2)
C70.38088 (9)0.59962 (17)0.20875 (10)0.0228 (2)
H7A0.38900.56560.28590.027*
H7B0.35610.72760.20140.027*
C80.48008 (9)0.58239 (19)0.16523 (12)0.0288 (3)
H8A0.50300.45470.17140.043*
H8B0.53020.66180.20670.043*
H8C0.47150.61960.08940.043*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0167 (4)0.0153 (3)0.0259 (4)−0.0009 (3)0.0038 (3)0.0019 (3)
N10.0155 (4)0.0179 (4)0.0215 (4)−0.0004 (3)0.0028 (3)−0.0003 (3)
C10.0167 (5)0.0174 (5)0.0191 (5)−0.0014 (4)0.0040 (4)−0.0035 (4)
C20.0169 (5)0.0228 (5)0.0302 (6)−0.0047 (4)0.0050 (4)−0.0015 (4)
C30.0244 (5)0.0165 (5)0.0241 (5)−0.0020 (4)0.0037 (4)0.0034 (4)
C40.0267 (6)0.0207 (5)0.0330 (6)0.0025 (5)0.0001 (5)0.0041 (5)
C50.0179 (5)0.0196 (5)0.0253 (5)−0.0024 (4)0.0047 (4)0.0029 (4)
C60.0188 (5)0.0264 (6)0.0365 (7)0.0031 (4)0.0000 (5)0.0062 (5)
S10.01773 (13)0.01682 (13)0.01937 (13)0.00004 (9)0.00569 (9)−0.00045 (9)
O20.0169 (4)0.0233 (4)0.0267 (4)−0.0015 (3)0.0065 (3)−0.0075 (3)
O30.0238 (4)0.0363 (5)0.0346 (5)−0.0081 (4)0.0076 (4)−0.0156 (4)
O40.0233 (4)0.0194 (4)0.0363 (5)0.0051 (3)0.0069 (4)0.0039 (3)
O50.0379 (5)0.0309 (5)0.0250 (4)−0.0011 (4)0.0090 (4)0.0098 (4)
C70.0195 (5)0.0248 (5)0.0239 (5)−0.0019 (4)0.0021 (4)−0.0029 (4)
C80.0192 (5)0.0293 (6)0.0381 (7)−0.0004 (5)0.0049 (5)−0.0012 (5)
Geometric parameters (Å, º) top
O1—C11.3157 (13)C5—H5B0.9800
O1—C31.4629 (13)C5—H5C0.9800
N1—C11.2981 (14)C6—H6A0.9800
N1—C51.4658 (14)C6—H6B0.9800
N1—C61.4707 (15)C6—H6C0.9800
C1—C21.4848 (15)S1—O31.4390 (9)
C2—H2A0.9800S1—O51.4433 (9)
C2—H2B0.9800S1—O41.4440 (9)
C2—H2C0.9800S1—O21.6175 (9)
C3—C41.5001 (18)O2—C71.4356 (14)
C3—H3A0.9900C7—C81.5079 (17)
C3—H3B0.9900C7—H7A0.9900
C4—H4A0.9800C7—H7B0.9900
C4—H4B0.9800C8—H8A0.9800
C4—H4C0.9800C8—H8B0.9800
C5—H5A0.9800C8—H8C0.9800
C1—O1—C3119.31 (9)N1—C5—H5C109.5
C1—N1—C5120.66 (10)H5A—C5—H5C109.5
C1—N1—C6122.44 (10)H5B—C5—H5C109.5
C5—N1—C6116.88 (9)N1—C6—H6A109.5
N1—C1—O1115.55 (10)N1—C6—H6B109.5
N1—C1—C2123.23 (10)H6A—C6—H6B109.5
O1—C1—C2121.22 (10)N1—C6—H6C109.5
C1—C2—H2A109.5H6A—C6—H6C109.5
C1—C2—H2B109.5H6B—C6—H6C109.5
H2A—C2—H2B109.5O3—S1—O5114.46 (6)
C1—C2—H2C109.5O3—S1—O4114.95 (6)
H2A—C2—H2C109.5O5—S1—O4113.02 (6)
H2B—C2—H2C109.5O3—S1—O2101.21 (5)
O1—C3—C4106.41 (9)O5—S1—O2105.75 (6)
O1—C3—H3A110.4O4—S1—O2105.84 (5)
C4—C3—H3A110.4C7—O2—S1116.46 (7)
O1—C3—H3B110.4O2—C7—C8107.41 (10)
C4—C3—H3B110.4O2—C7—H7A110.2
H3A—C3—H3B108.6C8—C7—H7A110.2
C3—C4—H4A109.5O2—C7—H7B110.2
C3—C4—H4B109.5C8—C7—H7B110.2
H4A—C4—H4B109.5H7A—C7—H7B108.5
C3—C4—H4C109.5C7—C8—H8A109.5
H4A—C4—H4C109.5C7—C8—H8B109.5
H4B—C4—H4C109.5H8A—C8—H8B109.5
N1—C5—H5A109.5C7—C8—H8C109.5
N1—C5—H5B109.5H8A—C8—H8C109.5
H5A—C5—H5B109.5H8B—C8—H8C109.5
C5—N1—C1—O1−0.51 (15)C1—O1—C3—C4168.71 (10)
C6—N1—C1—O1177.86 (10)O3—S1—O2—C7174.76 (9)
C5—N1—C1—C2−179.82 (10)O5—S1—O2—C7−65.61 (9)
C6—N1—C1—C2−1.45 (17)O4—S1—O2—C754.55 (9)
C3—O1—C1—N1178.90 (9)S1—O2—C7—C8−178.39 (8)
C3—O1—C1—C2−1.77 (15)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C5—H5B···O5i0.982.323.288 (2)170
C2—H2A···O3ii0.982.403.341 (2)161
C3—H3A···O50.992.503.121 (2)120
C5—H5A···O2iii0.982.513.372 (2)147
C6—H6B···O5i0.982.543.453 (2)154
C4—H4B···O2iv0.982.553.452 (2)154
Symmetry codes: (i) x, y+1, z; (ii) −x, y+1/2, −z+1/2; (iii) x, −y+3/2, z+1/2; (iv) x, −y+1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C5—H5B···O5i0.982.323.288 (2)170
C2—H2A···O3ii0.982.403.341 (2)161
C3—H3A···O50.992.503.121 (2)120
C5—H5A···O2iii0.982.513.372 (2)147
C6—H6B···O5i0.982.543.453 (2)154
C4—H4B···O2iv0.982.553.452 (2)154
Symmetry codes: (i) x, y+1, z; (ii) −x, y+1/2, −z+1/2; (iii) x, −y+3/2, z+1/2; (iv) x, −y+1/2, z+1/2.
 

Acknowledgements

The authors thank Dr W. Frey (Institut für Organische Chemie, Universität Stuttgart) for measuring the diffraction data.

References

First citationBlessing, R. H. (1995). Acta Cryst. A51, 33–38.  CrossRef CAS Web of Science IUCr Journals Google Scholar
 First citationBrandenburg, K. & Putz, H. (2005). DIAMOND. Crystal Impact GbR, Bonn, Germany.  Google Scholar
 First citationBruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationKarapetyan, H. A. (2008). Acta Cryst. E64, o1982.  Web of Science CSD CrossRef IUCr Journals Google Scholar
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 First citationTiritiris, I., Saur, S. & Kantlehner, W. (2014a). Acta Cryst. E70, o333.  CSD CrossRef IUCr Journals Google Scholar
 First citationTiritiris, I., Saur, S. & Kantlehner, W. (2014b). Acta Cryst. E70, o459.  CSD CrossRef IUCr Journals Google Scholar

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 71| Part 12| December 2015| Page o916
https://doi.org/10.1107/S2056989015020678
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