1-Dodecyl-3-methyl­imidazolium bromide monohydrate

The asymmetric unit of the title compound, C₁₆H₃₁N₂⁺·Br^-·H₂O, contains one crystallographically independent 1-do­decyl-3-methyl­imidazolium cation, one bromide anion, to counterbalance the charge, and one solvent water mol­ecule. The halide anion forms hydrogen bonds with the H atoms of the imidazole ring and with the water H atoms.

Key indicators

• Single-crystal X-ray study
• T = 263 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.026
• wR factor = 0.069
• Data-to-parameter ratio = 21.9

checkCIF/PLATON results

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Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.98
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

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

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Computing details

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 1996); software used to prepare material for publication: SHELXL97.

1-Dodecyl-3-methylimidazolium bromide monohydrate

Crystal data

C16H31N2^+·Br^−·H2O	Z = 2
Mr = 349.34	F(000) = 372
Triclinic, P1	Dx = 1.221 Mg m^−3
Hall symbol: -P 1	Melting point: unknown K
a = 5.500 (5) Å	Mo Kα radiation, λ = 0.71073 Å
b = 7.794 (5) Å	Cell parameters from 4273 reflections
c = 22.961 (5) Å	θ = 2.8–28.3°
α = 81.893 (5)°	µ = 2.16 mm^−1
β = 83.761 (5)°	T = 263 K
γ = 78.102 (5)°	Needle, white
V = 950.3 (11) Å^3	0.3 × 0.2 × 0.1 mm

Data collection

Stoe IPDS-I diffractometer	4167 independent reflections
Radiation source: fine-focus sealed tube	3523 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.034
φ scans	θmax = 27.3°, θmin = 1.8°
Absorption correction: numerical [X-RED32 (Stoe & Cie, 2002) and X-SHAPE (Stoe & Cie, 2001)]	h = −6→7
Tmin = 0.585, Tmax = 0.794	k = −9→9
14912 measured reflections	l = −29→29

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.026	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.069	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0397P)^2 + 0.1463P] where P = (Fo^2 + 2Fc^2)/3
4167 reflections	(Δ/σ)max = 0.001
190 parameters	Δρmax = 0.24 e Å^−3
2 restraints	Δρmin = −0.29 e Å^−3

Special details

Experimental. A suitable single-crystal was carefully selected under a polarizing microscope and mounted in a glass capillary. The scattering intensities were collected with an imaging plate diffractometer (Stoe IPDS-I) equipped with a fine focus sealed tube X-ray source (Mo Kα, λ = 0.71073 Å) operating at 50 kV and 30 mA. Intensity data were collected at 263 K by φ scans in 360 frames (0 < φ < 180° exposure time of 10 min) in the 2Θ range 1.91 - 54.78 °·Structure solution and refinement were carried out using the program SHELXL97 (Sheldrick, 1997). A numerical absorption correction (X-RED (Stoe & Cie, 2001) was applied after optimization of the crystal shape (X-SHAPE (Stoe & Cie, 2001)). The final difference maps were free of any chemically significant features. The refinement was based on F² for ALL reflections.

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. Carbon-bound H atoms were positioned with idealized geometry (methine d(C—H) = 93 pm, methylene: d(C—H) = 99 pm; methyl: d(C—H) = 98 pm) and refined with fixed isotropic displacement parameters [U_iso(H)=1.5U_eq (for methyl C) and U_iso(H)=1.2U_eq (for methylene C)] using a riding atom model. The methyl groups were idealized, then refined as a rigid group allowed to rotate but not tip. The water H atoms were located in a difference map and their bond length restrained.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
Br	0.73175 (3)	0.32730 (3)	0.383956 (8)	0.05446 (8)
N1	0.4615 (3)	−0.05054 (19)	0.36555 (6)	0.0442 (3)
N2	0.6005 (3)	−0.21059 (19)	0.44379 (6)	0.0463 (3)
O	0.1671 (4)	0.5835 (3)	0.34933 (13)	0.1026 (7)
H1O	0.315 (4)	0.528 (4)	0.3517 (16)	0.128 (13)*
H2O	0.084 (5)	0.500 (3)	0.3521 (15)	0.110 (11)*
C1	0.6543 (3)	−0.1654 (2)	0.38675 (8)	0.0472 (4)
H1	0.8025	−0.2072	0.3652	0.057*
C2	0.3659 (3)	−0.1219 (2)	0.45970 (8)	0.0506 (4)
H2	0.2822	−0.1296	0.4971	0.061*
C3	0.2797 (3)	−0.0214 (3)	0.41077 (8)	0.0505 (4)
H3	0.1252	0.0538	0.4082	0.061*
C4	0.4544 (4)	0.0394 (3)	0.30472 (8)	0.0525 (4)
H4A	0.6050	−0.0089	0.2817	0.063*
H4B	0.4522	0.1639	0.3053	0.063*
C5	0.2312 (3)	0.0207 (2)	0.27513 (7)	0.0469 (4)
H5A	0.0796	0.0754	0.2965	0.056*
H5B	0.2278	−0.1035	0.2758	0.056*
C6	0.2431 (4)	0.1079 (3)	0.21164 (8)	0.0505 (4)
H6A	0.2505	0.2312	0.2116	0.061*
H6B	0.3959	0.0524	0.1909	0.061*
C7	0.0246 (3)	0.0978 (3)	0.17806 (7)	0.0498 (4)
H7A	−0.1281	0.1563	0.1980	0.060*
H7B	0.0143	−0.0253	0.1788	0.060*
C8	0.0437 (3)	0.1816 (3)	0.11422 (8)	0.0502 (4)
H8A	0.0524	0.3049	0.1137	0.060*
H8B	0.1981	0.1242	0.0946	0.060*
C9	−0.1699 (4)	0.1712 (3)	0.07940 (8)	0.0502 (4)
H9A	−0.3246	0.2284	0.0990	0.060*
H9B	−0.1783	0.0480	0.0796	0.060*
C10	−0.1486 (3)	0.2563 (3)	0.01589 (8)	0.0503 (4)
H10A	0.0062	0.1991	−0.0036	0.060*
H10B	−0.1401	0.3794	0.0157	0.060*
C11	−0.3622 (4)	0.2466 (3)	−0.01946 (8)	0.0507 (4)
H11A	−0.5172	0.3038	0.0000	0.061*
H11B	−0.3708	0.1235	−0.0194	0.061*
C12	−0.3394 (4)	0.3321 (3)	−0.08305 (8)	0.0506 (4)
H12A	−0.3312	0.4552	−0.0831	0.061*
H12B	−0.1840	0.2751	−0.1023	0.061*
C13	−0.5513 (4)	0.3224 (3)	−0.11872 (8)	0.0513 (4)
H13A	−0.5584	0.1992	−0.1190	0.062*
H13B	−0.7069	0.3782	−0.0991	0.062*
C14	−0.5312 (4)	0.4089 (3)	−0.18186 (8)	0.0579 (5)
H14A	−0.5254	0.5323	−0.1817	0.070*
H14B	−0.3755	0.3535	−0.2015	0.070*
C15	−0.7430 (5)	0.3974 (3)	−0.21700 (10)	0.0725 (6)
H15A	−0.7183	0.4551	−0.2564	0.109*
H15B	−0.8978	0.4543	−0.1985	0.109*
H15C	−0.7473	0.2756	−0.2185	0.109*
C16	0.7654 (4)	−0.3362 (3)	0.48298 (9)	0.0606 (5)
H16A	0.6680	−0.3808	0.5168	0.091*	0.50
H16B	0.8842	−0.2775	0.4956	0.091*	0.50
H16C	0.8518	−0.4325	0.4622	0.091*	0.50
H16D	0.9347	−0.3464	0.4662	0.091*	0.50
H16E	0.7184	−0.4496	0.4875	0.091*	0.50
H16F	0.7509	−0.2947	0.5209	0.091*	0.50

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br	0.05039 (11)	0.05782 (12)	0.05377 (11)	−0.00501 (8)	−0.01003 (8)	−0.00571 (8)
N1	0.0451 (7)	0.0469 (7)	0.0403 (7)	−0.0070 (6)	−0.0101 (6)	−0.0025 (6)
N2	0.0477 (8)	0.0453 (7)	0.0441 (7)	−0.0008 (6)	−0.0135 (6)	−0.0043 (6)
O	0.0575 (10)	0.0631 (11)	0.175 (2)	−0.0021 (9)	0.0001 (12)	0.0037 (12)
C1	0.0429 (8)	0.0494 (9)	0.0477 (9)	−0.0024 (7)	−0.0071 (7)	−0.0084 (7)
C2	0.0489 (9)	0.0588 (10)	0.0413 (9)	−0.0022 (8)	−0.0060 (7)	−0.0069 (8)
C3	0.0438 (9)	0.0561 (10)	0.0476 (9)	0.0023 (8)	−0.0089 (7)	−0.0065 (8)
C4	0.0568 (11)	0.0591 (11)	0.0434 (9)	−0.0174 (9)	−0.0123 (8)	0.0027 (8)
C5	0.0492 (9)	0.0526 (9)	0.0396 (8)	−0.0115 (8)	−0.0081 (7)	−0.0026 (7)
C6	0.0525 (10)	0.0569 (10)	0.0432 (9)	−0.0158 (8)	−0.0099 (8)	0.0021 (8)
C7	0.0517 (10)	0.0584 (10)	0.0406 (9)	−0.0176 (8)	−0.0089 (7)	0.0036 (7)
C8	0.0508 (10)	0.0597 (10)	0.0412 (9)	−0.0165 (8)	−0.0083 (7)	0.0024 (7)
C9	0.0521 (10)	0.0577 (10)	0.0420 (9)	−0.0164 (8)	−0.0094 (8)	0.0020 (8)
C10	0.0511 (10)	0.0584 (10)	0.0428 (9)	−0.0160 (8)	−0.0084 (8)	0.0009 (8)
C11	0.0537 (10)	0.0579 (10)	0.0421 (9)	−0.0168 (8)	−0.0092 (8)	0.0008 (8)
C12	0.0527 (10)	0.0574 (10)	0.0432 (9)	−0.0165 (8)	−0.0088 (8)	0.0006 (8)
C13	0.0548 (10)	0.0564 (10)	0.0439 (9)	−0.0148 (8)	−0.0094 (8)	−0.0002 (8)
C14	0.0631 (12)	0.0675 (12)	0.0443 (9)	−0.0183 (10)	−0.0104 (9)	0.0023 (8)
C15	0.0807 (15)	0.0894 (16)	0.0504 (11)	−0.0223 (13)	−0.0224 (11)	0.0028 (11)
C16	0.0626 (12)	0.0563 (11)	0.0569 (11)	0.0072 (9)	−0.0230 (9)	−0.0005 (9)

Geometric parameters (Å, º)

N1—C1	1.327 (2)	C9—C10	1.517 (2)
N1—C3	1.370 (2)	C9—H9A	0.9700
N1—C4	1.472 (2)	C9—H9B	0.9700
N2—C1	1.325 (2)	C10—C11	1.518 (3)
N2—C2	1.370 (2)	C10—H10A	0.9700
N2—C16	1.467 (2)	C10—H10B	0.9700
O—H1O	0.842 (18)	C11—C12	1.521 (2)
O—H2O	0.859 (18)	C11—H11A	0.9700
C1—H1	0.9300	C11—H11B	0.9700
C2—C3	1.347 (2)	C12—C13	1.515 (3)
C2—H2	0.9300	C12—H12A	0.9700
C3—H3	0.9300	C12—H12B	0.9700
C4—C5	1.508 (3)	C13—C14	1.513 (2)
C4—H4A	0.9700	C13—H13A	0.9700
C4—H4B	0.9700	C13—H13B	0.9700
C5—C6	1.520 (2)	C14—C15	1.511 (3)
C5—H5A	0.9700	C14—H14A	0.9700
C5—H5B	0.9700	C14—H14B	0.9700
C6—C7	1.517 (3)	C15—H15A	0.9600
C6—H6A	0.9700	C15—H15B	0.9600
C6—H6B	0.9700	C15—H15C	0.9600
C7—C8	1.520 (2)	C16—H16A	0.9600
C7—H7A	0.9700	C16—H16B	0.9600
C7—H7B	0.9700	C16—H16C	0.9600
C8—C9	1.513 (3)	C16—H16D	0.9600
C8—H8A	0.9700	C16—H16E	0.9600
C8—H8B	0.9700	C16—H16F	0.9600
C1—N1—C3	108.37 (15)	C9—C10—H10B	108.7
C1—N1—C4	125.22 (15)	C11—C10—H10B	108.7
C3—N1—C4	126.26 (15)	H10A—C10—H10B	107.6
C1—N2—C2	108.71 (14)	C10—C11—C12	114.00 (16)
C1—N2—C16	125.31 (16)	C10—C11—H11A	108.8
C2—N2—C16	125.98 (16)	C12—C11—H11A	108.8
H1O—O—H2O	103 (3)	C10—C11—H11B	108.8
N2—C1—N1	108.66 (15)	C12—C11—H11B	108.8
N2—C1—H1	125.7	H11A—C11—H11B	107.6
N1—C1—H1	125.7	C13—C12—C11	114.36 (16)
C3—C2—N2	106.90 (16)	C13—C12—H12A	108.7
C3—C2—H2	126.5	C11—C12—H12A	108.7
N2—C2—H2	126.5	C13—C12—H12B	108.7
C2—C3—N1	107.36 (16)	C11—C12—H12B	108.7
C2—C3—H3	126.3	H12A—C12—H12B	107.6
N1—C3—H3	126.3	C14—C13—C12	114.63 (16)
N1—C4—C5	113.05 (15)	C14—C13—H13A	108.6
N1—C4—H4A	109.0	C12—C13—H13A	108.6
C5—C4—H4A	109.0	C14—C13—H13B	108.6
N1—C4—H4B	109.0	C12—C13—H13B	108.6
C5—C4—H4B	109.0	H13A—C13—H13B	107.6
H4A—C4—H4B	107.8	C15—C14—C13	114.08 (18)
C4—C5—C6	110.22 (15)	C15—C14—H14A	108.7
C4—C5—H5A	109.6	C13—C14—H14A	108.7
C6—C5—H5A	109.6	C15—C14—H14B	108.7
C4—C5—H5B	109.6	C13—C14—H14B	108.7
C6—C5—H5B	109.6	H14A—C14—H14B	107.6
H5A—C5—H5B	108.1	C14—C15—H15A	109.5
C7—C6—C5	114.32 (16)	C14—C15—H15B	109.5
C7—C6—H6A	108.7	H15A—C15—H15B	109.5
C5—C6—H6A	108.7	C14—C15—H15C	109.5
C7—C6—H6B	108.7	H15A—C15—H15C	109.5
C5—C6—H6B	108.7	H15B—C15—H15C	109.5
H6A—C6—H6B	107.6	N2—C16—H16A	109.5
C6—C7—C8	113.41 (16)	N2—C16—H16B	109.5
C6—C7—H7A	108.9	H16A—C16—H16B	109.5
C8—C7—H7A	108.9	N2—C16—H16C	109.5
C6—C7—H7B	108.9	H16A—C16—H16C	109.5
C8—C7—H7B	108.9	H16B—C16—H16C	109.5
H7A—C7—H7B	107.7	N2—C16—H16D	109.5
C9—C8—C7	114.58 (16)	H16A—C16—H16D	141.1
C9—C8—H8A	108.6	H16B—C16—H16D	56.3
C7—C8—H8A	108.6	H16C—C16—H16D	56.3
C9—C8—H8B	108.6	N2—C16—H16E	109.5
C7—C8—H8B	108.6	H16A—C16—H16E	56.3
H8A—C8—H8B	107.6	H16B—C16—H16E	141.1
C8—C9—C10	113.90 (16)	H16C—C16—H16E	56.3
C8—C9—H9A	108.8	H16D—C16—H16E	109.5
C10—C9—H9A	108.8	N2—C16—H16F	109.5
C8—C9—H9B	108.8	H16A—C16—H16F	56.3
C10—C9—H9B	108.8	H16B—C16—H16F	56.3
H9A—C9—H9B	107.7	H16C—C16—H16F	141.1
C9—C10—C11	114.33 (16)	H16D—C16—H16F	109.5
C9—C10—H10A	108.7	H16E—C16—H16F	109.5
C11—C10—H10A	108.7

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O—H2O···Br^i	0.86 (2)	2.57 (2)	3.386 (3)	159 (3)
O—H1O···Br	0.84 (2)	2.61 (2)	3.435 (3)	166 (3)
C3—H3···Br^i	0.93	2.75	3.661 (3)	167
C1—H1···O^ii	0.93	2.34	3.193 (4)	152

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