Crystal structure of 1-butyl-2,3-di­methyl­imidazolium dicarba-7,8-nido-undeca­borate

Klemes, M.J.; Soderstrom, L.; Hunting, J.L.; Larsen, A.S.

doi:10.1107/S2056989015002765

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 71| Part 3| March 2015| Page o183

doi:10.1107/S2056989015002765

Open

access

Crystal structure of 1-butyl-2,3-dimethylimidazolium dicarba-7,8-nido-undecaborate

M. J. Klemes,^a L. Soderstrom,^a J. L. Hunting ^a and A. S. Larsen ^a ^*

^aDepartment of Chemistry, Ithaca College, 953 Danby Road, Ithaca, NY 14850, USA
^*Correspondence e-mail: alarsen@ithaca.edu

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 25 November 2014; accepted 9 February 2015; online 13 February 2015)

In the title molecular salt, C₉H₁₇N₂⁺·C₂H₁₂B₉⁻, the carborane cage has a bridging B—H—B bond on the open B₃C₂ face. The butyl side chain of the cation adopts an extended conformation [C—C—C—C = 179.6 (1)°]. In the crystal, the imidazolium ring is almost coplanar with the open face of the carborane anion. The cations stack in the [010] direction and the dihedral angle between the imidazolium rings of adjacent cations is 68.45 (6)°. The butyl chains extend into the space between carborane anions.

Keywords: crystal structure; carborane cage anion; imidazolium cation; bridging B—H—B bond.

CCDC reference: 1048494

1. Related literature

For structural and thermodynamic properties of the title compound and similar boron cluster anion low-melting ionic compounds, see: Larsen et al. (2000 ); Dymon et al. (2008 ); Suarez et al. (2011 ). A similar bridging hydrogen atom was reported by Jones et al. 1997 in an analogous crystal structure.

2. Experimental

2.1. Crystal data

C₉H₁₇N₂⁺·C₂H₁₂B₉⁻
M_r = 286.78
Monoclinic, P 2₁ /n
a = 9.5242 (2) Å
b = 11.5173 (2) Å
c = 16.3357 (3) Å
β = 104.821 (1)°
V = 1732.30 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.06 mm⁻¹
T = 100 K
0.42 × 0.32 × 0.26 mm

2.2. Data collection

Bruker SMART CCD 1K area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2012 ) T_min = 0.701, T_max = 0.746
27028 measured reflections
3964 independent reflections
3582 reflections with I > 2σ(I)
R_int = 0.021

2.3. Refinement

R[F² > 2σ(F²)] = 0.043
wR(F²) = 0.120
S = 1.05
3964 reflections
225 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.40 e Å⁻³
Δρ_min = −0.28 e Å⁻³

Data collection: APEX2 (Bruker, 2012); cell refinement: SAINT (Bruker, 2012); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015 ); molecular graphics: OLEX2 (Dolomanov et al., 2009 ); software used to prepare material for publication: OLEX2.

Supporting information

CCDC reference: 1048494

Crystal structure: contains datablock I. DOI: 10.1107/S2056989015002765/hb7327sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2056989015002765/hb7327Isup2.hkl

checkCIF report

Comment top

The title compound was synthesized as part of a study of low melting ionic compounds with carborane cage anions. (Larsen et al. 2000, Dymon et al. 2008, Suarez et al. 2011). The formula unit consists of a carborane anion and an alkylated imidazolium cation. A similar bridging hydrogen atom was also seen, for example, by Jones et al. 1997 in an analogous crystal structure. In the crystal packing the imidazolium rings are almost coplanar with open face of the carborane anions. The angle between two orientations of coplanar imidazolium rings is 68.45°. The butyl chains form interlinking pattern extending into the space between carborane anions. The carborane anion possesses a bridging hydrogen at the open face of the cage (shown on Figure 1).

Related literature top

For structural and thermodynamic properties of the title compound and similar boron cluster anion low-melting ionic compounds, see: Larsen et al. (2000); Dymon et al. (2008); Suarez et al. (2011). A similar bridging hydrogen atom was reported by Jones et al. 1997 in an analogous crystal structure.

Experimental top

Caesium dicarba-7,8-nido-undecaborate was synthesized according to published procedure (Dymon et al. 2008). Caesium dicarba-7,8-nido-undecaborate (0.300 g, 1.14 mmol) was dissolved in acetone (2 ml). This solution was added to 1-butyl-2,3-dimethylimidazolium chloride (0.215 g, 1.14 mmol) dissolved in dichloromethane (30 ml). The turbid solution was stirred at room temperature for 30 minutes. The mixture was filtered through a plug of celite to remove the caesium chloride precipitate. The volatiles were removed in vacuo and the residue was dissolved in dichloromethane (30 ml) and filtered via celite again. The dichloromethane was removed in vacuo. The solid residue was dissolved in a small amount of absolute ethanol and crystals were grown by slow vapor diffusion of hexane into the absolute ethanol solution at 233 K.

Computing details top

Data collection: APEX2 (Bruker, 2012); cell refinement: SAINT (Bruker, 2012); data reduction: SAINT (Bruker, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Figures top

	Fig. 1. Crystal structure of the title compound with displacement ellipsoids at the 50% probability level.
	Fig. 2. Packing diagram of the title compound, showing coplanar alignment of the imidazolium rings and parallel butyl chains. The angle between two orientations of coplanar imidazolium rings is 68.45°.
	Fig. 3. Packing diagram of the title compound showing the imidazolium rings nearly coplanar with the open B3C2 face. For clarity, H-atoms are removed.

1-Butyl-2,3-dimethylimidazolium dicarba-7,8-nido-undecaborate top

Crystal data top

C₉H₁₇N₂⁺·C₂H₁₂B₉⁻	F(000) = 616
M_r = 286.78	D_x = 1.099 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
a = 9.5242 (2) Å	Cell parameters from 3582 reflections
b = 11.5173 (2) Å	θ = 2.2–27.5°
c = 16.3357 (3) Å	µ = 0.06 mm⁻¹
β = 104.821 (1)°	T = 100 K
V = 1732.30 (6) Å³	Prism, clear light colourless
Z = 4	0.42 × 0.32 × 0.26 mm

Data collection top

Bruker SMART CCD 1K area-detector diffractometer	3964 independent reflections
Radiation source: sealed X-ray tube	3582 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.021
Detector resolution: 7.9 pixels mm^-1	θ_max = 27.5°, θ_min = 2.2°
ω scans	h = −12→12
Absorption correction: multi-scan (SADABS; Bruker, 2012)	k = −14→14
T_min = 0.701, T_max = 0.746	l = −21→20
27028 measured reflections

Refinement top

Refinement on F²	37 constraints
Least-squares matrix: full	Primary atom site location: structure-invariant direct methods
R[F² > 2σ(F²)] = 0.043	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.120	w = 1/[σ²(F_o²) + (0.0633P)² + 0.7865P] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max = 0.004
3964 reflections	Δρ_max = 0.40 e Å⁻³
225 parameters	Δρ_min = −0.28 e Å⁻³
0 restraints

Crystal data top

C₉H₁₇N₂⁺·C₂H₁₂B₉⁻	V = 1732.30 (6) Å³
M_r = 286.78	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 9.5242 (2) Å	µ = 0.06 mm⁻¹
b = 11.5173 (2) Å	T = 100 K
c = 16.3357 (3) Å	0.42 × 0.32 × 0.26 mm
β = 104.821 (1)°

Data collection top

Bruker SMART CCD 1K area-detector diffractometer	3964 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2012)	3582 reflections with I > 2σ(I)
T_min = 0.701, T_max = 0.746	R_int = 0.021
27028 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.043	0 restraints
wR(F²) = 0.120	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	Δρ_max = 0.40 e Å⁻³
3964 reflections	Δρ_min = −0.28 e Å⁻³
225 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
N1	0.76133 (10)	0.49244 (8)	0.20979 (6)	0.0148 (2)
N2	0.67739 (10)	0.47136 (8)	0.31974 (6)	0.0149 (2)
C3	0.85032 (13)	0.52932 (10)	0.15375 (7)	0.0201 (2)
H3a	0.8045 (5)	0.5960 (5)	0.1201 (4)	0.0301 (4)*
H3b	0.9471 (3)	0.5514 (8)	0.18769 (8)	0.0301 (4)*
H3c	0.8590 (8)	0.4653 (3)	0.1159 (4)	0.0301 (4)*
C6	0.90467 (12)	0.59313 (10)	0.34029 (7)	0.0195 (2)
H6a	0.99760 (12)	0.5562 (4)	0.3408 (5)	0.0292 (4)*
H6b	0.9000 (6)	0.6697 (3)	0.3136 (3)	0.0292 (4)*
H6c	0.8963 (6)	0.6019 (7)	0.39853 (18)	0.0292 (4)*
C5	0.78385 (12)	0.51986 (9)	0.29174 (7)	0.0145 (2)
C4	0.63722 (12)	0.42556 (9)	0.18504 (7)	0.0169 (2)
H4	0.59636 (12)	0.39499 (9)	0.13008 (7)	0.0203 (3)*
C7	0.58539 (12)	0.41206 (9)	0.25370 (7)	0.0167 (2)
H7	0.50115 (12)	0.36962 (9)	0.25636 (7)	0.0200 (3)*
C8	0.66132 (12)	0.47245 (10)	0.40748 (7)	0.0165 (2)
H8a	0.72201 (12)	0.53512 (10)	0.43998 (7)	0.0198 (3)*
H8b	0.55882 (12)	0.48834 (10)	0.40668 (7)	0.0198 (3)*
C9	0.70717 (12)	0.35634 (10)	0.45034 (7)	0.0178 (2)
H9a	0.64746 (12)	0.29405 (10)	0.41672 (7)	0.0214 (3)*
H9b	0.80982 (12)	0.34134 (10)	0.45104 (7)	0.0214 (3)*
C10	0.69123 (12)	0.35140 (10)	0.54080 (7)	0.0164 (2)
H10a	0.75173 (12)	0.41286 (10)	0.57497 (7)	0.0197 (3)*
H10b	0.58876 (12)	0.36634 (10)	0.54054 (7)	0.0197 (3)*
C11	0.73738 (13)	0.23351 (10)	0.58104 (7)	0.0205 (2)
H11a	0.7246 (10)	0.2324 (3)	0.6387 (2)	0.0308 (4)*
H11b	0.6775 (7)	0.17259 (13)	0.5473 (3)	0.0308 (4)*
H11c	0.8397 (3)	0.2197 (4)	0.5830 (5)	0.0308 (4)*
C2	0.17288 (12)	0.08417 (9)	0.42860 (7)	0.0147 (2)
C1	0.21122 (12)	0.08264 (9)	0.34140 (7)	0.0149 (2)
B5	0.33450 (13)	0.14839 (11)	0.42313 (8)	0.0167 (2)
H5	0.44690 (13)	0.11671 (11)	0.45362 (8)	0.0201 (3)*
B6	0.22452 (13)	0.21212 (11)	0.48302 (8)	0.0158 (2)
H6	0.26690 (13)	0.22484 (11)	0.55298 (8)	0.0190 (3)*
B1	0.04205 (13)	0.16869 (11)	0.43443 (8)	0.0147 (2)
B2	−0.01661 (13)	0.23783 (11)	0.33083 (8)	0.0150 (2)
B3	0.10220 (13)	0.16468 (11)	0.27283 (8)	0.0153 (2)
B4	0.28625 (13)	0.20985 (11)	0.32130 (8)	0.0161 (2)
H4a	0.36949 (13)	0.22198 (11)	0.28446 (8)	0.0193 (3)*
B9	0.28663 (13)	0.29761 (11)	0.40908 (8)	0.0161 (2)
H9	0.36735 (13)	0.36940 (11)	0.42941 (8)	0.0193 (3)*
B7	0.10328 (13)	0.30870 (10)	0.41803 (8)	0.0147 (2)
H7a	0.06430 (13)	0.38730 (10)	0.44608 (8)	0.0176 (3)*
B8	0.14080 (13)	0.30817 (11)	0.31390 (8)	0.0154 (2)
H8	0.12680 (13)	0.38547 (11)	0.27096 (8)	0.0185 (3)*
H2	0.1878 (15)	0.0099 (13)	0.4581 (9)	0.019 (3)*
H2a	−0.1222 (16)	0.2751 (13)	0.2999 (9)	0.025 (4)*
H1	0.2458 (16)	0.0102 (14)	0.3259 (9)	0.024 (4)*
H1a	−0.0255 (15)	0.1466 (12)	0.4776 (9)	0.020 (3)*
H3	0.0733 (16)	0.1437 (13)	0.2064 (9)	0.022 (4)*
H2b	−0.0116 (18)	0.1414 (15)	0.3104 (10)	0.038 (4)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0161 (4)	0.0128 (4)	0.0155 (4)	0.0003 (3)	0.0040 (3)	0.0013 (3)
N2	0.0157 (4)	0.0125 (4)	0.0168 (5)	0.0006 (3)	0.0049 (3)	−0.0002 (3)
C3	0.0226 (6)	0.0218 (6)	0.0174 (5)	−0.0036 (4)	0.0080 (4)	0.0018 (4)
C6	0.0191 (5)	0.0163 (5)	0.0208 (6)	−0.0031 (4)	0.0010 (4)	−0.0010 (4)
C5	0.0166 (5)	0.0112 (5)	0.0158 (5)	0.0031 (4)	0.0045 (4)	0.0019 (4)
C4	0.0164 (5)	0.0134 (5)	0.0191 (5)	0.0000 (4)	0.0013 (4)	−0.0006 (4)
C7	0.0149 (5)	0.0131 (5)	0.0208 (5)	−0.0009 (4)	0.0025 (4)	−0.0001 (4)
C8	0.0201 (5)	0.0158 (5)	0.0161 (5)	0.0014 (4)	0.0091 (4)	−0.0003 (4)
C9	0.0205 (5)	0.0179 (5)	0.0168 (5)	0.0059 (4)	0.0081 (4)	0.0017 (4)
C10	0.0174 (5)	0.0179 (5)	0.0142 (5)	0.0033 (4)	0.0045 (4)	−0.0011 (4)
C11	0.0258 (6)	0.0212 (6)	0.0150 (5)	0.0065 (4)	0.0059 (4)	0.0013 (4)
C2	0.0176 (5)	0.0120 (5)	0.0151 (5)	0.0005 (4)	0.0055 (4)	0.0016 (4)
C1	0.0166 (5)	0.0129 (5)	0.0165 (5)	0.0003 (4)	0.0067 (4)	−0.0014 (4)
B5	0.0138 (5)	0.0173 (6)	0.0187 (6)	0.0015 (4)	0.0035 (4)	0.0006 (5)
B6	0.0175 (6)	0.0153 (6)	0.0142 (5)	0.0010 (4)	0.0032 (4)	−0.0003 (4)
B1	0.0152 (5)	0.0145 (6)	0.0156 (6)	0.0002 (4)	0.0060 (4)	0.0013 (4)
B2	0.0128 (5)	0.0152 (6)	0.0167 (6)	0.0004 (4)	0.0033 (4)	0.0007 (4)
B3	0.0159 (6)	0.0161 (6)	0.0146 (5)	−0.0017 (4)	0.0052 (4)	−0.0005 (4)
B4	0.0150 (5)	0.0167 (6)	0.0180 (6)	−0.0015 (4)	0.0067 (4)	−0.0000 (5)
B9	0.0144 (5)	0.0156 (6)	0.0178 (6)	−0.0021 (4)	0.0034 (4)	−0.0005 (4)
B7	0.0161 (6)	0.0126 (5)	0.0157 (5)	0.0006 (4)	0.0048 (4)	−0.0007 (4)
B8	0.0169 (6)	0.0139 (5)	0.0157 (6)	−0.0011 (4)	0.0047 (4)	0.0018 (4)

Geometric parameters (Å, º) top

N1—C3	1.4608 (14)	C1—B5	1.7125 (16)
N1—C5	1.3382 (14)	C1—B3	1.6219 (16)
N1—C4	1.3819 (14)	C1—B4	1.6986 (16)
N2—C5	1.3367 (14)	C1—H1	0.955 (16)
N2—C7	1.3836 (14)	B5—H5	1.1200
N2—C8	1.4798 (13)	B5—B6	1.7656 (17)
C3—H3a	0.9800	B5—B4	1.7574 (18)
C3—H3b	0.9800	B5—B9	1.7778 (18)
C3—H3c	0.9800	B6—H6	1.1200
C6—H6a	0.9800	B6—B1	1.7873 (17)
C6—H6b	0.9800	B6—B9	1.7732 (18)
C6—H6c	0.9800	B6—B7	1.7524 (17)
C6—C5	1.4827 (15)	B1—B2	1.8238 (17)
C4—H4	0.9500	B1—B7	1.7584 (17)
C4—C7	1.3451 (16)	B1—H1a	1.099 (14)
C7—H7	0.9500	B2—B3	1.8538 (17)
C8—H8a	0.9900	B2—B7	1.7796 (17)
C8—H8b	0.9900	B2—B8	1.7868 (17)
C8—C9	1.5208 (15)	B2—H2a	1.091 (15)
C9—H9a	0.9900	B2—H2b	1.165 (17)
C9—H9b	0.9900	B3—B4	1.8056 (17)
C9—C10	1.5246 (14)	B3—B8	1.7862 (17)
C10—H10a	0.9900	B3—H3	1.077 (14)
C10—H10b	0.9900	B3—H2b	1.401 (16)
C10—C11	1.5236 (15)	B4—H4a	1.1200
C11—H11a	0.9800	B4—B9	1.7536 (18)
C11—H11b	0.9800	B4—B8	1.7693 (18)
C11—H11c	0.9800	B9—H9	1.1200
C2—C1	1.5585 (14)	B9—B7	1.7938 (17)
C2—B5	1.7305 (16)	B9—B8	1.8046 (18)
C2—B6	1.7263 (16)	B7—H7a	1.1200
C2—B1	1.6030 (16)	B7—B8	1.8254 (17)
C2—H2	0.975 (15)	B8—H8	1.1200

C5—N1—C3	126.02 (10)	B6—B1—C2	60.93 (7)
C4—N1—C3	124.66 (10)	B2—B1—C2	105.57 (8)
C4—N1—C5	109.30 (9)	B2—B1—B6	108.80 (8)
C7—N2—C5	108.90 (9)	B7—B1—C2	104.76 (8)
C8—N2—C5	127.11 (9)	B7—B1—B6	59.23 (7)
C8—N2—C7	123.89 (9)	B7—B1—B2	59.54 (7)
H3a—C3—N1	109.5	H1a—B1—C2	119.3 (7)
H3b—C3—N1	109.5	H1a—B1—B6	116.2 (7)
H3b—C3—H3a	109.5	H1a—B1—B2	127.3 (7)
H3c—C3—N1	109.5	H1a—B1—B7	125.5 (7)
H3c—C3—H3a	109.5	B3—B2—B1	101.16 (8)
H3c—C3—H3b	109.5	B7—B2—B1	58.40 (7)
H6b—C6—H6a	109.5	B7—B2—B3	105.48 (8)
H6c—C6—H6a	109.5	B8—B2—B1	105.76 (8)
H6c—C6—H6b	109.5	B8—B2—B3	58.73 (7)
C5—C6—H6a	109.5	B8—B2—B7	61.57 (7)
C5—C6—H6b	109.5	H2a—B2—B1	128.9 (8)
C5—C6—H6c	109.5	H2a—B2—B3	123.6 (8)
N2—C5—N1	107.59 (9)	H2a—B2—B7	121.1 (8)
C6—C5—N1	124.98 (10)	H2a—B2—B8	117.4 (8)
C6—C5—N2	127.42 (10)	H2b—B2—B1	79.9 (8)
H4—C4—N1	126.59 (6)	H2b—B2—B3	49.1 (8)
C7—C4—N1	106.82 (10)	H2b—B2—B7	127.0 (8)
C7—C4—H4	126.59 (7)	H2b—B2—B8	106.9 (8)
C4—C7—N2	107.39 (9)	H2b—B2—H2a	110.1 (11)
H7—C7—N2	126.31 (6)	B2—B3—C1	106.17 (8)
H7—C7—C4	126.31 (7)	B4—B3—C1	59.13 (7)
H8a—C8—N2	109.56 (6)	B4—B3—B2	107.22 (8)
H8b—C8—N2	109.56 (6)	B8—B3—C1	104.23 (8)
H8b—C8—H8a	108.1	B8—B3—B2	58.76 (7)
C9—C8—N2	110.48 (9)	B8—B3—B4	59.02 (7)
C9—C8—H8a	109.56 (6)	H3—B3—C1	121.3 (8)
C9—C8—H8b	109.56 (6)	H3—B3—B2	125.8 (8)
H9a—C9—C8	108.98 (6)	H3—B3—B4	118.4 (8)
H9b—C9—C8	108.98 (6)	H3—B3—B8	124.1 (8)
H9b—C9—H9a	107.8	H2b—B3—C1	90.9 (7)
C10—C9—C8	113.02 (9)	H2b—B3—B2	38.9 (7)
C10—C9—H9a	108.98 (6)	H2b—B3—B4	129.5 (7)
C10—C9—H9b	108.98 (6)	H2b—B3—B8	96.9 (7)
H10a—C10—C9	109.39 (6)	H2b—B3—H3	111.8 (10)
H10b—C10—C9	109.39 (6)	B5—B4—C1	59.38 (7)
H10b—C10—H10a	108.0	B3—B4—C1	55.04 (6)
C11—C10—C9	111.23 (9)	B3—B4—B5	106.77 (8)
C11—C10—H10a	109.39 (6)	H4a—B4—C1	127.03 (5)
C11—C10—H10b	109.39 (6)	H4a—B4—B5	120.62 (6)
H11a—C11—C10	109.5	H4a—B4—B3	122.79 (5)
H11b—C11—C10	109.5	B9—B4—C1	104.60 (8)
H11b—C11—H11a	109.5	B9—B4—B5	60.84 (7)
H11c—C11—C10	109.5	B9—B4—B3	108.87 (8)
H11c—C11—H11a	109.5	B9—B4—H4a	120.92 (6)
H11c—C11—H11b	109.5	B8—B4—C1	101.80 (8)
B5—C2—C1	62.50 (7)	B8—B4—B5	109.46 (9)
B6—C2—C1	112.20 (8)	B8—B4—B3	59.94 (7)
B6—C2—B5	61.43 (7)	B8—B4—H4a	122.20 (6)
B1—C2—C1	115.37 (9)	B8—B4—B9	61.62 (7)
B1—C2—B5	117.30 (9)	B6—B9—B5	59.63 (7)
B1—C2—B6	64.82 (7)	B4—B9—B5	59.68 (7)
H2—C2—C1	113.8 (8)	B4—B9—B6	107.80 (9)
H2—C2—B5	112.5 (8)	H9—B9—B5	122.78 (5)
H2—C2—B6	120.6 (8)	H9—B9—B6	122.09 (6)
H2—C2—B1	121.4 (8)	H9—B9—B4	121.72 (6)
B5—C1—C2	63.68 (7)	B7—B9—B5	106.33 (8)
B3—C1—C2	111.49 (8)	B7—B9—B6	58.85 (7)
B3—C1—B5	118.09 (9)	B7—B9—B4	108.02 (8)
B4—C1—C2	112.05 (8)	B7—B9—H9	122.14 (6)
B4—C1—B5	62.02 (7)	B8—B9—B5	106.97 (8)
B4—C1—B3	65.83 (7)	B8—B9—B6	107.88 (8)
H1—C1—C2	115.4 (9)	B8—B9—B4	59.62 (7)
H1—C1—B5	112.3 (9)	B8—B9—H9	121.63 (5)
H1—C1—B3	122.0 (9)	B8—B9—B7	60.97 (7)
H1—C1—B4	120.8 (9)	B1—B7—B6	61.21 (7)
C1—B5—C2	53.82 (6)	B2—B7—B6	112.47 (8)
H5—B5—C2	126.83 (5)	B2—B7—B1	62.06 (7)
H5—B5—C1	126.11 (5)	B9—B7—B6	59.99 (7)
B6—B5—C2	59.17 (7)	B9—B7—B1	108.35 (8)
B6—B5—C1	103.31 (8)	B9—B7—B2	109.93 (8)
B6—B5—H5	121.61 (6)	H7a—B7—B6	120.08 (6)
B4—B5—C2	101.56 (8)	H7a—B7—B1	121.43 (5)
B4—B5—C1	58.60 (7)	H7a—B7—B2	119.10 (5)
B4—B5—H5	122.74 (6)	H7a—B7—B9	121.49 (6)
B4—B5—B6	107.97 (8)	B8—B7—B6	107.87 (8)
B9—B5—C2	102.58 (8)	B8—B7—B1	106.89 (8)
B9—B5—C1	102.99 (8)	B8—B7—B2	59.41 (7)
B9—B5—H5	123.83 (5)	B8—B7—B9	59.81 (7)
B9—B5—B6	60.05 (7)	B8—B7—H7a	123.25 (5)
B9—B5—B4	59.47 (7)	B3—B8—B2	62.51 (7)
B5—B6—C2	59.40 (7)	B4—B8—B2	111.87 (8)
H6—B6—C2	128.17 (5)	B4—B8—B3	61.04 (7)
H6—B6—B5	120.64 (6)	B9—B8—B2	109.11 (8)
B1—B6—C2	54.26 (6)	B9—B8—B3	107.48 (8)
B1—B6—B5	106.55 (8)	B9—B8—B4	58.76 (7)
B1—B6—H6	123.06 (5)	B7—B8—B2	59.02 (7)
B9—B6—C2	102.94 (8)	B7—B8—B3	106.41 (8)
B9—B6—B5	60.31 (7)	B7—B8—B4	105.96 (8)
B9—B6—H6	121.77 (6)	B7—B8—B9	59.23 (7)
B9—B6—B1	107.98 (8)	H8—B8—B2	119.15 (5)
B7—B6—C2	99.97 (8)	H8—B8—B3	121.34 (5)
B7—B6—B5	108.69 (8)	H8—B8—B4	121.15 (6)
B7—B6—H6	123.01 (6)	H8—B8—B9	122.36 (5)
B7—B6—B1	59.56 (7)	H8—B8—B7	124.10 (5)
B7—B6—B9	61.16 (7)	B3—H2b—B2	92.0 (11)

Experimental details

Crystal data
Chemical formula	C₉H₁₇N₂⁺·C₂H₁₂B₉⁻
M_r	286.78
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	100
a, b, c (Å)	9.5242 (2), 11.5173 (2), 16.3357 (3)
β (°)	104.821 (1)
V (Å³)	1732.30 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.06
Crystal size (mm)	0.42 × 0.32 × 0.26

Data collection
Diffractometer	Bruker SMART CCD 1K area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2012)
T_min, T_max	0.701, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	27028, 3964, 3582
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.043, 0.120, 1.05
No. of reflections	3964
No. of parameters	225
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.40, −0.28

Computer programs: APEX2 (Bruker, 2012), SAINT (Bruker, 2012), SHELXS97 (Sheldrick, 2008), SHELXL2013 (Sheldrick, 2015), OLEX2 (Dolomanov et al., 2009).

Acknowledgements

AL thanks Professor Maitland Jones for the generous donation of the starting orthocarborane stock and Dr John Holbrey for the supply of imidazolium halide reagents. The research support by ACS PRF and Cottrell College awards (44692.01-GB and CC6755) is gratefully acknowledged.

References

Bruker (2012). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339–341. Web of Science CrossRef CAS IUCr Journals Google Scholar
Dymon, J., Wibby, R., Kleingardner, J., Tanski, J. M., Guzei, I. A., Holbrey, J. D. & Larsen, A. S. (2008). Dalton Trans. pp. 2999–3006. Web of Science CSD CrossRef Google Scholar
Jones, P. G., Villacampa, M. D., Crespo, O., Gimeno, M. C. & Laguna, A. (1997). Acta Cryst. C53, 570–572. CSD CrossRef CAS Web of Science IUCr Journals Google Scholar
Larsen, A. S., Holbrey, J. D., Tham, F. S. & Reed, C. A. (2000). J. Am. Chem. Soc. 122, 7264–7272. Web of Science CSD CrossRef CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (2015). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar
Suarez, S. A., Foi, A., Eady, S., Larsen, A. & Doctorovich, F. (2011). Acta Cryst. C67, o417–o420. Web of Science CSD CrossRef IUCr Journals Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.