[(Di­methyl­amino)­meth­yl]di­methyl­aza­nium bis­(tri­fluoro­methane­sulfon­yl)amide

Hummel, M.; Laus, G.; Kahlenberg, V.; Schottenberger, H.

doi:10.1107/S2414314616016588

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 1| Part 10| October 2016| x161658

https://doi.org/10.1107/S2414314616016588

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[(Dimethylamino)methyl]dimethylazanium bis(trifluoromethanesulfonyl)amide

Michael Hummel,^a Gerhard Laus,^b ^* Volker Kahlenberg ^c and Herwig Schottenberger ^b

^aAalto University, Department of Forest Products Technology, PO Box 16300, 00076 Aalto, Finland, ^bUniversity of Innsbruck, Faculty of Chemistry and Pharmacy, Innrain 80, 6020 Innsbruck, Austria, and ^cUniversity of Innsbruck, Institute of Mineralogy and Petrography, Innrain 52, 6020 Innsbruck, Austria
^*Correspondence e-mail: gerhard.laus@uibk.ac.at

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 15 October 2016; accepted 17 October 2016; online 21 October 2016)

The title molecular salt, C₅H₁₅N₂⁺·C₂F₆NO₄S₂⁻, was obtained by a proton transfer reaction between bis(trifluoromethanesulfonyl)amine and bis(dimethylamino)methane. In the crystal, the ions are linked by N—H⋯O=S hydrogen bonds, and these units are linked by C—H⋯O hydrogen bonds, forming sheets parallel to the bc plane. The crystal was refined as a non-merohedral twin with a BASF factor of 0.316 (1).

Keywords: crystal structure; bis(triflimide); ionic liquid; hydrogen bonding.

CCDC reference: 1510243

Structure description

The molecular structure of the title compound is shown in Fig. 1. The bis(dimethylamino)methane molecule is protonated resulting in a mono-cation. Bis(trifluoromethanesulfonyl)amides [also called `bis(triflimides)'] are known to exist as either syn or anti conformers in the solid state (Bentivoglio et al., 2009 ; Laus et al., 2011 ). Here, the anion adopts an anti conformation with a C6—S1⋯S2—C7 torsion angle of 169.4 (1)°. The negative charge of the anion is effectively delocalized, thus bestowing only weak coordinating properties.

Figure 1
The molecular structure of the ion pair of the title molecular salt, with atom labelling and 50% probability displacement ellipsoids.

In the crystal, N—H⋯O=S hydrogen bonds link the ions and one strong and two weaker C—H⋯O=S hydrogen bonds link these units, forming sheets parallel to the bc plane (Figs. 2 and 3, Table 1). No direct contacts to the triflimide nitrogen N3 atom were detected.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2⋯O4ⁱ	0.87 (2)	2.08 (2)	2.868 (3)	150 (2)
N2—H2⋯O2ⁱ	0.87 (2)	2.46 (2)	3.115 (2)	133 (2)
C5—H5A⋯O3ⁱⁱ	0.98	2.38	3.299 (3)	156
C4—H4C⋯O3ⁱⁱ	0.98	2.59	3.444 (3)	145
C5—H5B⋯O1ⁱⁱⁱ	0.98	2.57	3.423 (3)	145
Symmetry codes: (i) x, y, z-1; (ii) -x+1, -y, -z+1; (iii) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Figure 2
Crystal packing of the title molecular salt. Hydrogen atoms have been omitted for clarity, except those engaged in N—H⋯O hydrogen bonding (see Table 1

Figure 3
A view along the a axis of the crystal packing of the title molecular salt. The hydrogen bonds are shown as dashed lines (see Table 1

), and, for clarity, only the H atoms involved in these interactions have been included.

This compound is another example of a low-melting, protic organic bis(triflimide) salt. Properties and applications of these protic Ionic Liquids (PILs) have been reviewed (Greaves & Drummond, 2008 ). The related structure of an organic liquid salt formed by a proton-transfer reaction between bis(trifluoromethanesulfonyl)amine and dimethylformamide has been reported (Cardenas & O'Hagan, 2016 ).

Synthesis and crystallization

Bis(dimethylamino)methane (1.20 g, 11.7 mmol) was added dropwise to bis((trifluoromethane)sulfonyl)amine (3.30 g, 11.7 mmol). The mixture was stirred at room temperature to yield a viscous, colourless liquid. Suitable crystals were obtained by slow cooling (m.p. 280–283 K). ¹H NMR (300 MHz, DMSO-d₆): δ 2.45 (s, 12H), 3.63 (s, 2H), 6.9 (br, 1H) p.p.m. ¹³C NMR (75 MHz, DMSO-d₆): δ 41.7, 80.7 (4 C), 119.5 (q, J = 322 Hz, 2C) p.p.m. IR (neat): ν 3172 (w), 2807 (w), 1345 (m), 1325 (m), 1179 (s), 1130 (s), 1052 (s), 790 (w), 741 (w), 612 (m), 570 (m), 510 (m) cm⁻¹.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. The crystal was refined as a non-merohedral twin [180° rotation about a*] with a BASF factor of 0.316 (1).

Table 2
Experimental details

Crystal data
Chemical formula	C₅H₁₅N₂⁺·C₂F₆NO₄S₂⁻
M_r	383.36
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	100
a, b, c (Å)	8.5071 (3), 20.9755 (8), 8.9099 (4)
β (°)	90.173 (3)
V (Å³)	1589.88 (11)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.42
Crystal size (mm)	0.24 × 0.20 × 0.20

Data collection
Diffractometer	Oxford Diffraction Gemini-R Ultra
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2008 $[Oxford Diffraction (2008). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ )
T_min, T_max	0.907, 0.922
No. of measured, independent and observed [I > 2σ(I)] reflections	9624, 2874, 2739
R_int	0.028
(sin θ/λ)_max (Å⁻¹)	0.600

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.032, 0.068, 1.06
No. of reflections	2874
No. of parameters	207
No. of restraints	1
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.33, −0.29
Computer programs: CrysAlis CCD and CrysAlis RED (Oxford Diffraction, 2008 $[Oxford Diffraction (2008). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ), SIR2002 (Burla et al., 2003 ), SHELXL97 (Sheldrick, 2008 ), ORTEP-3 for Windows (Farrugia, 2012 ) and Mercury (Macrae et al., 2008 ).

Structural data

CCDC reference: 1510243

Crystal structure: contains datablocks Global, I. DOI: https://doi.org/10.1107/S2414314616016588/su4084sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314616016588/su4084Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314616016588/su4084Isup3.mol

Supporting information file. DOI: https://doi.org/10.1107/S2414314616016588/su4084Isup4.cml

checkCIF report

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2008); cell refinement: CrysAlis CCD (Oxford Diffraction, 2008); data reduction: CrysAlis RED (Oxford Diffraction, 2008); program(s) used to solve structure: SIR2002 (Burla et al., 2003); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: Mercury (Macrae et al., 2008).

[(Dimethylamino)methyl]dimethylazanium bis(trifluoromethanesulfonyl)amide top

Crystal data top

C₅H₁₅N₂⁺·C₂F₆NO₄S₂⁻	F(000) = 784
M_r = 383.36	D_x = 1.602 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 6860 reflections
a = 8.5071 (3) Å	θ = 3.0–28.3°
b = 20.9755 (8) Å	µ = 0.42 mm⁻¹
c = 8.9099 (4) Å	T = 100 K
β = 90.173 (3)°	Block, colourless
V = 1589.88 (11) Å³	0.24 × 0.20 × 0.20 mm
Z = 4

Data collection top

Oxford Diffraction Gemini-R Ultra diffractometer	2874 independent reflections
Graphite monochromator	2739 reflections with I > 2σ(I)
Detector resolution: 10.3822 pixels mm^-1	R_int = 0.028
ω (1° width) scans	θ_max = 25.3°, θ_min = 3°
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2008)	h = −10→8
T_min = 0.907, T_max = 0.922	k = −25→23
9624 measured reflections	l = −9→10

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.032	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.068	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	w = 1/[σ²(F_o²) + (0.0373P)² + 0.4067P] where P = (F_o² + 2F_c²)/3
2874 reflections	(Δ/σ)_max < 0.001
207 parameters	Δρ_max = 0.33 e Å⁻³
1 restraint	Δρ_min = −0.29 e Å⁻³

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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

	x	y	z	U_iso*/U_eq
S1	0.57434 (6)	0.14606 (2)	0.75790 (7)	0.01443 (13)
S2	0.72783 (7)	0.03241 (2)	0.83172 (7)	0.01478 (13)
F4	0.95493 (16)	0.11210 (6)	0.77018 (17)	0.0269 (3)
F5	0.94238 (18)	0.03106 (7)	0.62282 (16)	0.0310 (4)
F3	0.33176 (17)	0.09974 (8)	0.89895 (19)	0.0346 (4)
F6	1.03258 (17)	0.01977 (8)	0.84722 (18)	0.0357 (4)
F1	0.29633 (17)	0.11073 (8)	0.66095 (18)	0.0385 (4)
F2	0.29664 (19)	0.19311 (8)	0.8058 (2)	0.0440 (5)
O4	0.73015 (19)	0.05025 (7)	0.98655 (18)	0.0195 (4)
O3	0.7037 (2)	−0.03286 (7)	0.79420 (19)	0.0248 (4)
O1	0.5888 (2)	0.18332 (7)	0.62404 (18)	0.0221 (4)
O2	0.6286 (2)	0.17340 (7)	0.89653 (19)	0.0209 (4)
N3	0.6242 (2)	0.07529 (9)	0.7246 (2)	0.0174 (4)
C7	0.9264 (3)	0.04976 (11)	0.7639 (3)	0.0202 (5)
C6	0.3619 (3)	0.13647 (12)	0.7819 (3)	0.0243 (6)
N2	0.6602 (2)	0.13384 (9)	0.2322 (2)	0.0166 (4)
H2	0.673 (3)	0.1214 (12)	0.140 (2)	0.02*
N1	0.9399 (2)	0.15256 (9)	0.2565 (2)	0.0219 (4)
C2	1.0467 (3)	0.15839 (14)	0.3829 (3)	0.0329 (7)
H2A	1.0838	0.2025	0.3903	0.049*
H2B	1.1366	0.1299	0.3683	0.049*
H2C	0.9918	0.1467	0.4754	0.049*
C4	0.6675 (3)	0.07490 (11)	0.3251 (3)	0.0206 (5)
H4A	0.6492	0.0858	0.4306	0.031*
H4B	0.7715	0.0553	0.3149	0.031*
H4C	0.5867	0.0449	0.2911	0.031*
C3	1.0159 (3)	0.16873 (17)	0.1164 (3)	0.0367 (7)
H3A	0.9404	0.1645	0.0337	0.055*
H3B	1.1047	0.1399	0.0996	0.055*
H3C	1.054	0.2128	0.121	0.055*
C5	0.5036 (3)	0.16500 (11)	0.2400 (3)	0.0208 (5)
H5A	0.4219	0.1341	0.2128	0.031*
H5B	0.5003	0.2011	0.1701	0.031*
H5C	0.4854	0.1804	0.3424	0.031*
C1	0.7886 (3)	0.18053 (11)	0.2756 (3)	0.0218 (5)
H1A	0.7802	0.2192	0.2124	0.026*
H1B	0.7751	0.1934	0.3816	0.026*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0148 (3)	0.0143 (3)	0.0142 (3)	0.0019 (2)	0.0018 (3)	0.0008 (2)
S2	0.0148 (3)	0.0135 (3)	0.0160 (3)	0.0019 (2)	0.0006 (2)	0.0001 (2)
F4	0.0225 (7)	0.0283 (8)	0.0300 (8)	−0.0057 (6)	0.0071 (6)	−0.0016 (7)
F5	0.0340 (8)	0.0377 (9)	0.0214 (8)	0.0056 (7)	0.0094 (6)	−0.0062 (6)
F3	0.0291 (8)	0.0415 (10)	0.0334 (9)	−0.0058 (7)	0.0131 (7)	0.0096 (8)
F6	0.0195 (7)	0.0522 (10)	0.0354 (9)	0.0134 (7)	0.0000 (7)	0.0087 (8)
F1	0.0197 (8)	0.0589 (11)	0.0371 (9)	−0.0018 (7)	−0.0073 (7)	−0.0010 (9)
F2	0.0282 (9)	0.0378 (9)	0.0661 (13)	0.0166 (7)	0.0141 (8)	−0.0004 (8)
O4	0.0220 (9)	0.0202 (9)	0.0164 (8)	0.0048 (7)	0.0021 (7)	0.0015 (7)
O3	0.0300 (9)	0.0152 (8)	0.0293 (10)	0.0008 (7)	−0.0009 (8)	−0.0003 (7)
O1	0.0281 (10)	0.0203 (9)	0.0180 (9)	0.0019 (7)	0.0051 (7)	0.0026 (7)
O2	0.0270 (9)	0.0178 (9)	0.0180 (9)	0.0019 (7)	−0.0004 (7)	−0.0028 (7)
N3	0.0182 (9)	0.0174 (10)	0.0166 (10)	0.0030 (8)	−0.0027 (8)	−0.0041 (8)
C7	0.0160 (11)	0.0263 (13)	0.0183 (13)	0.0043 (10)	0.0025 (11)	−0.0012 (11)
C6	0.0187 (12)	0.0254 (14)	0.0288 (16)	0.0052 (10)	0.0018 (11)	0.0024 (11)
N2	0.0193 (10)	0.0178 (10)	0.0128 (11)	0.0000 (7)	0.0025 (9)	−0.0026 (8)
N1	0.0168 (10)	0.0270 (11)	0.0218 (10)	−0.0001 (8)	0.0021 (10)	−0.0036 (10)
C2	0.0278 (15)	0.0428 (17)	0.0281 (15)	0.0009 (13)	−0.0014 (12)	0.0035 (13)
C4	0.0227 (13)	0.0173 (12)	0.0220 (13)	−0.0001 (9)	0.0021 (11)	0.0022 (11)
C3	0.0265 (15)	0.063 (2)	0.0212 (15)	0.0016 (14)	0.0039 (12)	−0.0037 (14)
C5	0.0192 (12)	0.0198 (12)	0.0232 (13)	−0.0001 (9)	0.0002 (11)	0.0009 (12)
C1	0.0212 (12)	0.0188 (12)	0.0255 (14)	−0.0020 (10)	0.0019 (11)	−0.0047 (10)

Geometric parameters (Å, º) top

S1—O1	1.4315 (17)	N1—C1	1.425 (3)
S1—O2	1.4368 (18)	N1—C3	1.448 (3)
S1—N3	1.5722 (19)	N1—C2	1.450 (3)
S1—C6	1.832 (3)	C2—H2A	0.98
S2—O3	1.4240 (16)	C2—H2B	0.98
S2—O4	1.4294 (17)	C2—H2C	0.98
S2—N3	1.578 (2)	C4—H4A	0.98
S2—C7	1.832 (2)	C4—H4B	0.98
F4—C7	1.331 (3)	C4—H4C	0.98
F5—C7	1.324 (3)	C3—H3A	0.98
F3—C6	1.322 (3)	C3—H3B	0.98
F6—C7	1.326 (3)	C3—H3C	0.98
F1—C6	1.327 (3)	C5—H5A	0.98
F2—C6	1.329 (3)	C5—H5B	0.98
N2—C5	1.486 (3)	C5—H5C	0.98
N2—C4	1.489 (3)	C1—H1A	0.99
N2—C1	1.516 (3)	C1—H1B	0.99
N2—H2	0.869 (17)

O1—S1—O2	118.04 (10)	C1—N1—C2	115.9 (2)
O1—S1—N3	109.54 (10)	C3—N1—C2	111.67 (19)
O2—S1—N3	116.91 (10)	N1—C2—H2A	109.5
O1—S1—C6	104.14 (11)	N1—C2—H2B	109.5
O2—S1—C6	104.96 (11)	H2A—C2—H2B	109.5
N3—S1—C6	100.69 (11)	N1—C2—H2C	109.5
O3—S2—O4	118.68 (10)	H2A—C2—H2C	109.5
O3—S2—N3	109.04 (10)	H2B—C2—H2C	109.5
O4—S2—N3	116.12 (10)	N2—C4—H4A	109.5
O3—S2—C7	104.23 (11)	N2—C4—H4B	109.5
O4—S2—C7	104.85 (11)	H4A—C4—H4B	109.5
N3—S2—C7	101.60 (11)	N2—C4—H4C	109.5
S1—N3—S2	125.08 (13)	H4A—C4—H4C	109.5
F5—C7—F6	108.61 (19)	H4B—C4—H4C	109.5
F5—C7—F4	108.18 (19)	N1—C3—H3A	109.5
F6—C7—F4	108.59 (19)	N1—C3—H3B	109.5
F5—C7—S2	110.58 (16)	H3A—C3—H3B	109.5
F6—C7—S2	110.36 (16)	N1—C3—H3C	109.5
F4—C7—S2	110.45 (15)	H3A—C3—H3C	109.5
F3—C6—F1	108.8 (2)	H3B—C3—H3C	109.5
F3—C6—F2	108.2 (2)	N2—C5—H5A	109.5
F1—C6—F2	108.6 (2)	N2—C5—H5B	109.5
F3—C6—S1	110.45 (17)	H5A—C5—H5B	109.5
F1—C6—S1	111.24 (17)	N2—C5—H5C	109.5
F2—C6—S1	109.46 (18)	H5A—C5—H5C	109.5
C5—N2—C4	112.00 (19)	H5B—C5—H5C	109.5
C5—N2—C1	110.43 (18)	N1—C1—N2	110.71 (18)
C4—N2—C1	111.44 (19)	N1—C1—H1A	109.5
C5—N2—H2	107.0 (17)	N2—C1—H1A	109.5
C4—N2—H2	105.7 (17)	N1—C1—H1B	109.5
C1—N2—H2	110.0 (17)	N2—C1—H1B	109.5
C1—N1—C3	114.3 (2)	H1A—C1—H1B	108.1

O1—S1—N3—S2	138.03 (15)	N3—S2—C7—F4	56.75 (17)
O2—S1—N3—S2	0.3 (2)	O1—S1—C6—F3	176.83 (16)
C6—S1—N3—S2	−112.65 (16)	O2—S1—C6—F3	−58.5 (2)
O3—S2—N3—S1	159.72 (14)	N3—S1—C6—F3	63.3 (2)
O4—S2—N3—S1	22.45 (19)	O1—S1—C6—F1	55.95 (19)
C7—S2—N3—S1	−90.63 (16)	O2—S1—C6—F1	−179.36 (16)
O3—S2—C7—F5	50.34 (18)	N3—S1—C6—F1	−57.55 (19)
O4—S2—C7—F5	175.75 (15)	O1—S1—C6—F2	−64.1 (2)
N3—S2—C7—F5	−62.96 (18)	O2—S1—C6—F2	60.59 (19)
O3—S2—C7—F6	−69.86 (18)	N3—S1—C6—F2	−177.60 (18)
O4—S2—C7—F6	55.55 (19)	C3—N1—C1—N2	97.3 (2)
N3—S2—C7—F6	176.83 (17)	C2—N1—C1—N2	−130.6 (2)
O3—S2—C7—F4	170.06 (16)	C5—N2—C1—N1	−175.3 (2)
O4—S2—C7—F4	−64.54 (18)	C4—N2—C1—N1	59.6 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2···O4ⁱ	0.87 (2)	2.08 (2)	2.868 (3)	150 (2)
N2—H2···O2ⁱ	0.87 (2)	2.46 (2)	3.115 (2)	133 (2)
C5—H5A···O3ⁱⁱ	0.98	2.38	3.299 (3)	156
C4—H4C···O3ⁱⁱ	0.98	2.59	3.444 (3)	145
C5—H5B···O1ⁱⁱⁱ	0.98	2.57	3.423 (3)	145

Symmetry codes: (i) x, y, z−1; (ii) −x+1, −y, −z+1; (iii) x, −y+1/2, z−1/2.

References

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