Crystal structure of di­methyl­formamidium bis­(tri­fluoro­methane­sulfon­yl)amide: an ionic liquid

The cation and anion of the title salt are linked by an O—H...N hydrogen bond and a C—H...O inter­action, resulting in a high viscosity and a crystallization temperature slightly lower than ambient temperature.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](F-C) = 0.002 Å
• R factor = 0.025
• wR factor = 0.066
• Data-to-parameter ratio = 22.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT242_ALERT_2_C Low    'MainMol' Ueq as Compared to Neighbors of         C1 Check
PLAT431_ALERT_2_C Short Inter HL..A  Contact F5     ..  O2      ..       2.87 Ang.
PLAT480_ALERT_4_C Long H...A H-Bond Reported H4     ..  O4      ..       2.63 Ang.
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          2 Report
PLAT978_ALERT_2_C Number C-C Bonds with Positive Residual Density           0 Note

Alert level G
PLAT005_ALERT_5_G No Embedded Refinement Details found  in the CIF     Please Do !
PLAT042_ALERT_1_G Calc. and Reported MoietyFormula Strings  Differ     Please Check
PLAT242_ALERT_2_G Low    'MainMol' Ueq as Compared to Neighbors of         C2 Check
PLAT380_ALERT_4_G Incorrectly? Oriented X(sp2)-Methyl Moiety .....         C6 Check
PLAT434_ALERT_2_G Short Inter HL..HL Contact F1     ..  F2      ..       2.71 Ang.
PLAT434_ALERT_2_G Short Inter HL..HL Contact F4     ..  F6      ..       2.79 Ang.
PLAT790_ALERT_4_G Centre of Gravity not Within Unit Cell: Resd.  #          2 Note
              C3 H8 N O
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600         24 Note
PLAT913_ALERT_3_G Missing # of Very Strong Reflections in FCF ....          1 Note

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   5 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   9 ALERT level G = General information/check it is not something unexpected

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   6 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   4 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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Computing details

Data collection: APEX2 (Bruker, 2013); cell refinement: SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Dimethylformamidium bis(trifluoromethanesulfonyl)amide

Crystal data

C3H8NO^+·C2F6NO4S2^−	Dx = 1.840 Mg m^−3
Mr = 354.25	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, P212121	Cell parameters from 9937 reflections
a = 9.0254 (9) Å	θ = 2.4–31.5°
b = 11.4601 (12) Å	µ = 0.51 mm^−1
c = 12.3621 (14) Å	T = 100 K
V = 1278.6 (2) Å^3	Block, colourless
Z = 4	0.40 × 0.30 × 0.30 mm
F(000) = 712

Data collection

Bruker APEXII CCD diffractometer	4274 independent reflections
Radiation source: fine-focus sealed tube	3989 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.033
φ and ω scans	θmax = 31.7°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 2015)	h = −13→12
Tmin = 0.582, Tmax = 0.746	k = −16→16
15926 measured reflections	l = −17→18

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.025	H-atom parameters constrained
wR(F^2) = 0.066	w = 1/[σ^2(Fo^2) + (0.0363P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.06	(Δ/σ)max = 0.001
4274 reflections	Δρmax = 0.29 e Å^−3
187 parameters	Δρmin = −0.30 e Å^−3
0 restraints	Absolute structure: Flack (1983)
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.01 (4)

Special details

Experimental. Absorption correction: SADABS-2014/5 (Bruker,2014/5) was used for absorption correction. wR2(int) was 0.0777 before and 0.0530 after correction. The Ratio of minimum to maximum transmission is 0.7795. The λ/2 correction factor is 0.00150.

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 (Ų)

	x	y	z	Uiso*/Ueq
S1	0.95481 (3)	0.01794 (3)	0.22331 (2)	0.02018 (7)
S2	1.05136 (3)	−0.05314 (3)	0.43097 (2)	0.01784 (6)
C3	1.44513 (14)	0.35694 (12)	0.10155 (11)	0.0239 (2)
H3A	1.3456	0.3670	0.0757	0.036*
H3B	1.5095	0.3401	0.0417	0.036*
H3C	1.4774	0.4272	0.1366	0.036*
F1	1.14157 (11)	−0.10684 (12)	0.11057 (9)	0.0507 (3)
F2	1.09712 (11)	0.15500 (8)	0.51280 (8)	0.0352 (2)
F3	0.97455 (13)	0.03798 (10)	0.61557 (7)	0.0455 (3)
F4	0.92510 (12)	−0.09329 (9)	0.04146 (7)	0.0428 (3)
F5	0.96239 (14)	−0.20423 (8)	0.17885 (9)	0.0472 (3)
F6	0.86942 (10)	0.11845 (9)	0.47659 (8)	0.0413 (2)
O1	0.80609 (10)	−0.00178 (9)	0.25752 (9)	0.0324 (3)
O2	0.99064 (13)	0.11860 (9)	0.16080 (8)	0.0338 (3)
O3	1.19216 (10)	−0.08639 (9)	0.47431 (8)	0.0276 (2)
O4	0.92949 (10)	−0.13268 (9)	0.43684 (8)	0.0250 (2)
N1	1.07837 (11)	0.00592 (10)	0.31584 (9)	0.0210 (2)
N2	1.44952 (11)	0.25990 (9)	0.17894 (8)	0.01757 (19)
O5	1.33633 (10)	0.11905 (9)	0.27429 (9)	0.0260 (2)
C1	0.99834 (15)	−0.10436 (13)	0.13368 (11)	0.0246 (3)
C2	0.99431 (14)	0.07208 (13)	0.51356 (11)	0.0253 (3)
C6	1.59693 (13)	0.22881 (13)	0.22087 (12)	0.0275 (3)
H6A	1.5879	0.1646	0.2703	0.041*
H6B	1.6389	0.2947	0.2578	0.041*
H6C	1.6602	0.2068	0.1618	0.041*
C4	1.33073 (12)	0.20433 (11)	0.20528 (10)	0.0193 (2)
H4	1.2405	0.2254	0.1747	0.023*
H5	1.265 (3)	0.0923 (19)	0.2902 (16)	0.051 (6)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.02305 (12)	0.01838 (15)	0.01912 (13)	0.00063 (11)	−0.00390 (11)	0.00356 (11)
S2	0.01587 (10)	0.01937 (14)	0.01828 (12)	−0.00017 (10)	−0.00079 (10)	0.00504 (11)
C3	0.0222 (5)	0.0239 (7)	0.0257 (6)	−0.0006 (5)	0.0031 (5)	0.0054 (5)
F1	0.0329 (5)	0.0708 (8)	0.0485 (6)	0.0044 (5)	0.0119 (4)	−0.0170 (6)
F2	0.0436 (5)	0.0245 (5)	0.0374 (5)	−0.0066 (4)	−0.0092 (4)	−0.0004 (4)
F3	0.0703 (7)	0.0429 (6)	0.0232 (4)	−0.0029 (6)	0.0124 (5)	0.0005 (4)
F4	0.0657 (7)	0.0352 (5)	0.0276 (4)	−0.0002 (5)	−0.0181 (5)	−0.0046 (4)
F5	0.0837 (8)	0.0191 (4)	0.0389 (5)	−0.0046 (5)	0.0122 (6)	0.0027 (4)
F6	0.0301 (4)	0.0410 (6)	0.0530 (6)	0.0141 (4)	−0.0011 (4)	−0.0103 (5)
O1	0.0185 (4)	0.0475 (7)	0.0310 (5)	0.0074 (4)	−0.0046 (4)	0.0018 (5)
O2	0.0586 (7)	0.0185 (5)	0.0244 (5)	−0.0065 (5)	−0.0123 (5)	0.0063 (4)
O3	0.0198 (4)	0.0349 (6)	0.0282 (5)	0.0041 (4)	−0.0056 (4)	0.0067 (4)
O4	0.0234 (4)	0.0233 (5)	0.0282 (5)	−0.0052 (3)	0.0004 (4)	0.0070 (4)
N1	0.0199 (4)	0.0258 (6)	0.0174 (4)	−0.0036 (4)	−0.0020 (4)	0.0069 (4)
N2	0.0162 (4)	0.0197 (5)	0.0167 (4)	0.0011 (4)	0.0015 (4)	−0.0013 (4)
O5	0.0199 (4)	0.0285 (5)	0.0295 (5)	−0.0032 (4)	0.0019 (4)	0.0088 (4)
C1	0.0294 (5)	0.0225 (7)	0.0220 (6)	−0.0014 (5)	0.0003 (5)	0.0024 (5)
C2	0.0275 (5)	0.0252 (7)	0.0231 (6)	−0.0001 (5)	0.0006 (5)	0.0013 (5)
C6	0.0166 (5)	0.0322 (8)	0.0336 (7)	−0.0001 (5)	−0.0030 (5)	0.0034 (6)
C4	0.0172 (4)	0.0223 (6)	0.0184 (5)	−0.0003 (4)	0.0013 (4)	−0.0011 (5)

Geometric parameters (Å, º)

S1—O1	1.4253 (10)	F2—C2	1.3282 (16)
S1—O2	1.4256 (11)	F3—C2	1.3321 (16)
S1—N1	1.6035 (11)	F4—C1	1.3239 (16)
S1—C1	1.8293 (15)	F5—C1	1.3141 (17)
S2—O3	1.4307 (9)	F6—C2	1.3273 (16)
S2—O4	1.4304 (9)	N2—C6	1.4716 (15)
S2—N1	1.5947 (11)	N2—C4	1.2888 (15)
S2—C2	1.8349 (15)	O5—C4	1.2983 (16)
C3—H3A	0.9600	O5—H5	0.74 (2)
C3—H3B	0.9600	C6—H6A	0.9600
C3—H3C	0.9600	C6—H6B	0.9600
C3—N2	1.4675 (16)	C6—H6C	0.9600
F1—C1	1.3242 (16)	C4—H4	0.9300
O1—S1—O2	120.18 (7)	C4—O5—H5	116.8 (16)
O1—S1—N1	115.44 (6)	F1—C1—S1	110.90 (11)
O1—S1—C1	105.10 (7)	F4—C1—S1	109.94 (10)
O2—S1—N1	107.36 (6)	F4—C1—F1	107.68 (12)
O2—S1—C1	104.06 (7)	F5—C1—S1	110.91 (10)
N1—S1—C1	102.53 (6)	F5—C1—F1	108.30 (13)
O3—S2—N1	108.15 (6)	F5—C1—F4	109.03 (13)
O3—S2—C2	104.43 (6)	F2—C2—S2	111.07 (9)
O4—S2—O3	119.62 (6)	F2—C2—F3	108.06 (11)
O4—S2—N1	115.68 (6)	F3—C2—S2	109.56 (10)
O4—S2—C2	104.73 (6)	F6—C2—S2	111.09 (9)
N1—S2—C2	101.98 (6)	F6—C2—F2	107.72 (12)
H3A—C3—H3B	109.5	F6—C2—F3	109.25 (12)
H3A—C3—H3C	109.5	N2—C6—H6A	109.5
H3B—C3—H3C	109.5	N2—C6—H6B	109.5
N2—C3—H3A	109.5	N2—C6—H6C	109.5
N2—C3—H3B	109.5	H6A—C6—H6B	109.5
N2—C3—H3C	109.5	H6A—C6—H6C	109.5
S2—N1—S1	124.53 (6)	H6B—C6—H6C	109.5
C3—N2—C6	115.95 (10)	N2—C4—O5	120.37 (11)
C4—N2—C3	121.11 (11)	N2—C4—H4	119.8
C4—N2—C6	122.92 (11)	O5—C4—H4	119.8
C3—N2—C4—O5	−179.64 (11)	O4—S2—N1—S1	21.78 (11)
O1—S1—N1—S2	14.69 (11)	O4—S2—C2—F2	−178.35 (9)
O1—S1—C1—F1	−169.55 (11)	O4—S2—C2—F3	62.34 (10)
O1—S1—C1—F4	71.48 (11)	O4—S2—C2—F6	−58.47 (11)
O1—S1—C1—F5	−49.18 (12)	N1—S1—C1—F1	−48.50 (12)
O2—S1—N1—S2	151.76 (9)	N1—S1—C1—F4	−167.47 (9)
O2—S1—C1—F1	63.26 (12)	N1—S1—C1—F5	71.88 (11)
O2—S1—C1—F4	−55.70 (11)	N1—S2—C2—F2	−57.43 (10)
O2—S1—C1—F5	−176.36 (10)	N1—S2—C2—F3	−176.74 (9)
O3—S2—N1—S1	159.07 (8)	N1—S2—C2—F6	62.45 (11)
O3—S2—C2—F2	55.11 (11)	C1—S1—N1—S2	−98.96 (9)
O3—S2—C2—F3	−64.20 (10)	C2—S2—N1—S1	−91.20 (9)
O3—S2—C2—F6	174.99 (10)	C6—N2—C4—O5	2.30 (19)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5···N1	0.74 (3)	1.98 (3)	2.7139 (14)	172 (2)
C4—H4···O2	0.93	2.57	3.2694 (16)	132
C4—H4···O4^i	0.93	2.63	3.4773 (16)	152

Symmetry code: (i) −x+2, y+1/2, −z+1/2.