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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 70| Part 2| February 2014| Pages o171-o172

1-Ethyl-3-methyl-1H-imidazol-3-ium spiro­penta­borate

aDepartment of Chemistry and Biochemistry, Florida State University, 95 Chieftain Way, Tallahassee, Florida 32306, USA
*Correspondence e-mail: albrecht-schmitt@chem.fsu.edu

(Received 17 October 2013; accepted 20 December 2013; online 18 January 2014)

In the anion of the title compound, (C6H11N2)[B5O6(OH)4], both six-membered borate rings adopt a flattened boat conformation with the spiro-B atom and its opposite O atom deviating from the remainders of the rings by 0.261 (3)/0.101 (2) and 0.160 (3)/0.109 (2) Å, respectively. The imidazolium cation also deviates from planarity due to rotation of the ethyl group (as indicated by the C—N—C—C torsion angle) by 71.4 (2)° out of the plane of the heterocycle. In the crystal, the anions are connected in a three-dimensional network through O—H⋯O hydrogen bonds, forming channels along the a-axis direction. The cations are situated in the channels, forming C—H⋯O hydrogen bonds with the anions.

Related literature

Several compounds with the same anion as the title compound, in addition to several anions that bear some similarities to it, have been prepared previously with a number of different cations. For an extensive analysis of these oxoboron compounds, please refer to the review by Lin & Yang (2011[Lin, Z.-E. & Yang, G.-Y. (2011). Eur. J. Inorg. Chem. 26, 3857-3867.]). The ionic liquid 1-ethyl-3-methyl­imidazolium bromide, from which the cation of the title compound originates, is one of the most common and easily synthesized ionic liquids available. For an extensive review of ionic liquid chemistry, including details on the preparation of imidazolium-based ionic liquids, please refer to the text by Wasserscheid & Welton (2003[Wasserscheid, P. & Welton, T. (2003). In Ionic Liquids in Synthesis. Weinheim: VCH.]).

[Scheme 1]

Experimental

Crystal data
  • C6H11N2+·B5H4O10

  • Mr = 329.25

  • Monoclinic, P 21 /c

  • a = 9.3599 (12) Å

  • b = 15.1128 (19) Å

  • c = 10.4770 (13) Å

  • β = 92.181 (2)°

  • V = 1480.9 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.13 mm−1

  • T = 100 K

  • 0.3 × 0.2 × 0.1 mm

Data collection
  • Bruker D8 Quest diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1997[Sheldrick, G. M. (1997). SADABS. University of Göttingen, Germany.]) Tmin = 0.970, Tmax = 0.987

  • 22780 measured reflections

  • 3404 independent reflections

  • 2902 reflections with I > 2σ(I)

  • Rint = 0.034

Refinement
  • R[F2 > 2σ(F2)] = 0.033

  • wR(F2) = 0.088

  • S = 1.04

  • 3404 reflections

  • 226 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.27 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O7—H1⋯O9i 0.88 (2) 1.84 (2) 2.7169 (12) 172.8 (17)
O8—H2⋯O2ii 0.861 (18) 1.843 (18) 2.7022 (12) 174.9 (17)
O9—H3⋯O3iii 0.87 (2) 1.80 (2) 2.6687 (11) 174.3 (18)
O10—H4⋯O4iv 0.85 (2) 1.90 (2) 2.7426 (12) 173.9 (19)
C1—H1A⋯O5iii 0.95 2.14 3.0265 (14) 155
C4—H4C⋯O10ii 0.98 2.47 3.4456 (16) 175
Symmetry codes: (i) x+1, y, z; (ii) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (iii) -x+2, -y, -z+1; (iv) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Data collection: SMART (Bruker, 2000[Bruker (2000). SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT; data reduction: SAINT and XPREP (Bruker, 1999[Bruker (1999). SAINT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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: SHELXP97 (2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and CrystalMaker (Kohn, 1995[Kohn, S. (1995). Terra Nova, 7, 554-556.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Experimental top

The title compound formed as a byproduct in the ionothermal flux synthesis of a lanthanide borate cluster. 50.2 mg of erbium (III) oxide (Atomergic Chemetals Corp., 99.9 %), 97.2 mg of boric acid (EMD, 99.5 %) and 766 mg of 1-ethyl-3-methyl­imidazolium bromide were loaded into a PTFE-lined stainless steel autoclave with an inter­nal volume of 23 mL in the presence of 100 mL of water for counterpressure. After heating for 3 days at 150 °C, the autoclave was cooled to 25 °C at a rate of 5 °C per hour. Colorless blocks of the title compound suitable for single crystal X-ray diffraction were isolated from the reaction.

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 1.

Results and discussion top

Related literature top

Several compounds with the same anion as the title compound, in addition to several anions that bear some similarities to it, have been prepared previously with a number of different cations. For an extensive analysis of these oxoboron compounds, please refer to the review by Lin & Yang (2011). The ionic liquid 1-ethyl-3-methylimidazolium bromide, from which the cation of the title compound originates, is one of the most common and easily synthesized ionic liquids available. For an extensive review of ionic liquid chemistry, including details on the preparation of imidazolium-based ionic liquids, please refer to the text by Wasserscheid & Welton (2003).

Refinement top

H atoms of hydroxy groups were found in a difference Fourier synthesis and refined isotropically. The rest of the H atoms were calculated geometrically and refined within a riding/rotating model with Uiso = 1.2Uiso/eq of the adjacent carbon atom (1.5 for CH3 group).

Structure description top

The title compound formed as a byproduct in the ionothermal flux synthesis of a lanthanide borate cluster. 50.2 mg of erbium (III) oxide (Atomergic Chemetals Corp., 99.9 %), 97.2 mg of boric acid (EMD, 99.5 %) and 766 mg of 1-ethyl-3-methyl­imidazolium bromide were loaded into a PTFE-lined stainless steel autoclave with an inter­nal volume of 23 mL in the presence of 100 mL of water for counterpressure. After heating for 3 days at 150 °C, the autoclave was cooled to 25 °C at a rate of 5 °C per hour. Colorless blocks of the title compound suitable for single crystal X-ray diffraction were isolated from the reaction.

Several compounds with the same anion as the title compound, in addition to several anions that bear some similarities to it, have been prepared previously with a number of different cations. For an extensive analysis of these oxoboron compounds, please refer to the review by Lin & Yang (2011). The ionic liquid 1-ethyl-3-methylimidazolium bromide, from which the cation of the title compound originates, is one of the most common and easily synthesized ionic liquids available. For an extensive review of ionic liquid chemistry, including details on the preparation of imidazolium-based ionic liquids, please refer to the text by Wasserscheid & Welton (2003).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT and XPREP (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXP97 (Sheldrick, 2008) and CrystalMaker (Kohn, 1995); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of 1-ethyl-3-methylimidazolium spiropentaborate including atomic numbering and 50% probability ellipsoids.
[Figure 2] Fig. 2. The view normal to the bc-plane showing the channels along which the cations reside. Hydrogen atoms not participating in hydrogen bonding have been omitted for clarity.
1-Ethyl-3-methyl-1H-imidazolium 4,8,10-tetrahydroxyspiro[5.5]pentaboroxan-6-uide top
Crystal data top
C6H11N2+·B5H4O10F(000) = 680
Mr = 329.25Dx = 1.477 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3404 reflections
a = 9.3599 (12) Åθ = 2.2–27.5°
b = 15.1128 (19) ŵ = 0.13 mm1
c = 10.4770 (13) ÅT = 100 K
β = 92.181 (2)°Block, colorless
V = 1480.9 (3) Å30.3 × 0.2 × 0.1 mm
Z = 4
Data collection top
Bruker D8 Quest
diffractometer
3404 independent reflections
Radiation source: Iµs microfocused2902 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
0.5° wide ω exposures scansθmax = 27.5°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1997)
h = 1212
Tmin = 0.970, Tmax = 0.987k = 1919
22780 measured reflectionsl = 1313
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.033Hydrogen site location: difference Fourier map
wR(F2) = 0.088H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.0442P)2 + 0.5004P]
where P = (Fo2 + 2Fc2)/3
3404 reflections(Δ/σ)max = 0.001
226 parametersΔρmax = 0.27 e Å3
0 restraintsΔρmin = 0.22 e Å3
Crystal data top
C6H11N2+·B5H4O10V = 1480.9 (3) Å3
Mr = 329.25Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.3599 (12) ŵ = 0.13 mm1
b = 15.1128 (19) ÅT = 100 K
c = 10.4770 (13) Å0.3 × 0.2 × 0.1 mm
β = 92.181 (2)°
Data collection top
Bruker D8 Quest
diffractometer
3404 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1997)
2902 reflections with I > 2σ(I)
Tmin = 0.970, Tmax = 0.987Rint = 0.034
22780 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0330 restraints
wR(F2) = 0.088H atoms treated by a mixture of independent and constrained refinement
S = 1.04Δρmax = 0.27 e Å3
3404 reflectionsΔρmin = 0.22 e Å3
226 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
O10.92508 (8)0.16731 (5)0.69807 (7)0.01589 (17)
O61.49330 (8)0.16170 (5)0.52890 (7)0.01567 (17)
O31.08727 (8)0.08183 (5)0.57803 (7)0.01407 (17)
O51.33102 (8)0.07833 (5)0.65159 (7)0.01398 (17)
O21.17600 (8)0.18727 (5)0.73424 (7)0.01490 (17)
O41.24439 (8)0.19660 (5)0.51455 (7)0.01469 (17)
O90.83683 (8)0.05749 (6)0.56047 (8)0.01843 (18)
O71.57125 (9)0.03768 (5)0.65252 (8)0.01789 (18)
O81.40915 (9)0.26406 (6)0.37734 (8)0.02090 (19)
O101.00812 (9)0.25571 (6)0.86757 (8)0.01941 (19)
B10.95195 (13)0.10211 (8)0.60986 (11)0.0140 (2)
B31.21157 (12)0.13593 (8)0.61957 (11)0.0128 (2)
B21.03975 (13)0.20424 (8)0.76705 (12)0.0146 (2)
B41.46484 (13)0.09275 (8)0.61107 (11)0.0136 (2)
B51.37948 (13)0.20780 (8)0.47349 (12)0.0146 (2)
N20.69980 (10)0.11782 (7)0.14371 (9)0.0194 (2)
N10.70973 (12)0.02735 (7)0.01465 (9)0.0227 (2)
C20.73105 (14)0.11083 (8)0.06212 (11)0.0217 (3)
H2A0.74740.12590.14840.026*
C30.72443 (13)0.16723 (8)0.03697 (11)0.0222 (3)
H3A0.73490.22970.03360.027*
C50.7149 (2)0.05582 (9)0.08757 (13)0.0378 (4)
H5A0.65480.05000.16690.045*
H5B0.67520.10440.03630.045*
C40.68454 (14)0.15161 (9)0.27388 (12)0.0270 (3)
H4A0.65550.10330.32960.041*
H4B0.61170.19820.27300.041*
H4C0.77620.17590.30590.041*
C10.69163 (14)0.03353 (9)0.11043 (11)0.0240 (3)
H1A0.67550.01460.16640.029*
C60.8655 (3)0.07868 (12)0.12121 (18)0.0576 (5)
H6A0.90590.03000.17010.086*
H6B0.86470.13280.17270.086*
H6C0.92380.08810.04270.086*
H11.656 (2)0.0489 (12)0.6215 (16)0.042 (5)*
H21.3336 (19)0.2818 (11)0.3353 (16)0.034 (4)*
H30.864 (2)0.0145 (13)0.5119 (18)0.047 (5)*
H41.081 (2)0.2741 (13)0.9101 (19)0.049 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0107 (4)0.0196 (4)0.0174 (4)0.0003 (3)0.0014 (3)0.0044 (3)
O60.0100 (4)0.0192 (4)0.0179 (4)0.0003 (3)0.0018 (3)0.0048 (3)
O30.0102 (4)0.0169 (4)0.0152 (4)0.0010 (3)0.0019 (3)0.0035 (3)
O50.0107 (4)0.0162 (4)0.0152 (4)0.0002 (3)0.0019 (3)0.0025 (3)
O20.0114 (4)0.0191 (4)0.0142 (4)0.0019 (3)0.0014 (3)0.0035 (3)
O40.0113 (4)0.0176 (4)0.0153 (4)0.0011 (3)0.0016 (3)0.0032 (3)
O90.0108 (4)0.0223 (4)0.0223 (4)0.0012 (3)0.0028 (3)0.0094 (3)
O70.0114 (4)0.0211 (4)0.0213 (4)0.0019 (3)0.0028 (3)0.0056 (3)
O80.0121 (4)0.0272 (5)0.0234 (4)0.0007 (3)0.0016 (3)0.0115 (3)
O100.0124 (4)0.0260 (4)0.0199 (4)0.0009 (3)0.0017 (3)0.0088 (3)
B10.0125 (5)0.0162 (6)0.0135 (5)0.0004 (4)0.0015 (4)0.0005 (4)
B30.0106 (5)0.0158 (6)0.0121 (5)0.0008 (4)0.0016 (4)0.0008 (4)
B20.0132 (6)0.0156 (6)0.0152 (6)0.0008 (4)0.0011 (4)0.0012 (4)
B40.0131 (5)0.0154 (6)0.0124 (5)0.0006 (4)0.0011 (4)0.0008 (4)
B50.0132 (6)0.0158 (6)0.0148 (5)0.0007 (4)0.0010 (4)0.0003 (4)
N20.0180 (5)0.0238 (5)0.0164 (5)0.0005 (4)0.0032 (4)0.0010 (4)
N10.0336 (6)0.0176 (5)0.0170 (5)0.0006 (4)0.0005 (4)0.0030 (4)
C20.0284 (6)0.0190 (6)0.0181 (5)0.0014 (5)0.0042 (5)0.0055 (4)
C30.0260 (6)0.0193 (6)0.0214 (6)0.0011 (5)0.0042 (5)0.0037 (5)
C50.0731 (11)0.0168 (6)0.0230 (6)0.0010 (7)0.0052 (7)0.0001 (5)
C40.0280 (7)0.0351 (7)0.0183 (6)0.0005 (5)0.0064 (5)0.0040 (5)
C10.0309 (7)0.0228 (6)0.0184 (6)0.0039 (5)0.0009 (5)0.0048 (5)
C60.0941 (15)0.0324 (9)0.0470 (10)0.0266 (9)0.0111 (10)0.0080 (7)
Geometric parameters (Å, º) top
O1—B11.3805 (14)N2—C11.3221 (17)
O1—B21.3881 (14)N2—C31.3715 (15)
O6—B51.3822 (14)N2—C41.4683 (15)
O6—B41.3839 (14)N1—C11.3311 (15)
O3—B11.3571 (14)N1—C21.3735 (15)
O3—B31.4740 (14)N1—C51.4726 (16)
O5—B41.3553 (14)C2—C31.3464 (17)
O5—B31.4463 (14)C2—H2A0.9500
O2—B21.3578 (14)C3—H3A0.9500
O2—B31.4788 (13)C5—C61.506 (3)
O4—B51.3615 (14)C5—H5A0.9900
O4—B31.4736 (14)C5—H5B0.9900
O9—B11.3569 (14)C4—H4A0.9800
O9—H30.87 (2)C4—H4B0.9800
O7—B41.3566 (15)C4—H4C0.9800
O7—H10.88 (2)C1—H1A0.9500
O8—B51.3550 (15)C6—H6A0.9800
O8—H20.861 (18)C6—H6B0.9800
O10—B21.3512 (15)C6—H6C0.9800
O10—H40.85 (2)
B1—O1—B2118.59 (9)C1—N1—C2108.53 (10)
B5—O6—B4118.51 (9)C1—N1—C5125.35 (11)
B1—O3—B3122.39 (9)C2—N1—C5126.02 (11)
B4—O5—B3123.09 (9)C3—C2—N1106.90 (10)
B2—O2—B3123.19 (9)C3—C2—H2A126.6
B5—O4—B3122.40 (9)N1—C2—H2A126.6
B1—O9—H3110.2 (12)C2—C3—N2107.35 (11)
B4—O7—H1114.9 (12)C2—C3—H3A126.3
B5—O8—H2112.8 (11)N2—C3—H3A126.3
B2—O10—H4113.9 (13)N1—C5—C6111.52 (14)
O9—B1—O3121.94 (10)N1—C5—H5A109.3
O9—B1—O1116.60 (10)C6—C5—H5A109.3
O3—B1—O1121.41 (10)N1—C5—H5B109.3
O5—B3—O4111.49 (9)C6—C5—H5B109.3
O5—B3—O3109.22 (9)H5A—C5—H5B108.0
O4—B3—O3108.02 (8)N2—C4—H4A109.5
O5—B3—O2108.86 (9)N2—C4—H4B109.5
O4—B3—O2109.87 (9)H4A—C4—H4B109.5
O3—B3—O2109.35 (8)N2—C4—H4C109.5
O10—B2—O2122.81 (10)H4A—C4—H4C109.5
O10—B2—O1116.70 (10)H4B—C4—H4C109.5
O2—B2—O1120.49 (10)N2—C1—N1108.60 (10)
O5—B4—O7118.49 (10)N2—C1—H1A125.7
O5—B4—O6121.20 (10)N1—C1—H1A125.7
O7—B4—O6120.31 (10)C5—C6—H6A109.5
O8—B5—O4122.14 (10)C5—C6—H6B109.5
O8—B5—O6116.87 (10)H6A—C6—H6B109.5
O4—B5—O6120.99 (10)C5—C6—H6C109.5
C1—N2—C3108.62 (10)H6A—C6—H6C109.5
C1—N2—C4124.99 (11)H6B—C6—H6C109.5
C3—N2—C4126.39 (11)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O7—H1···O9i0.88 (2)1.84 (2)2.7169 (12)172.8 (17)
O8—H2···O2ii0.861 (18)1.843 (18)2.7022 (12)174.9 (17)
O9—H3···O3iii0.87 (2)1.80 (2)2.6687 (11)174.3 (18)
O10—H4···O4iv0.85 (2)1.90 (2)2.7426 (12)173.9 (19)
C1—H1A···O5iii0.952.143.0265 (14)155
C4—H4C···O10ii0.982.473.4456 (16)175
Symmetry codes: (i) x+1, y, z; (ii) x, y+1/2, z1/2; (iii) x+2, y, z+1; (iv) x, y+1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O7—H1···O9i0.88 (2)1.84 (2)2.7169 (12)172.8 (17)
O8—H2···O2ii0.861 (18)1.843 (18)2.7022 (12)174.9 (17)
O9—H3···O3iii0.87 (2)1.80 (2)2.6687 (11)174.3 (18)
O10—H4···O4iv0.85 (2)1.90 (2)2.7426 (12)173.9 (19)
C1—H1A···O5iii0.952.143.0265 (14)154.9
C4—H4C···O10ii0.982.473.4456 (16)174.7
Symmetry codes: (i) x+1, y, z; (ii) x, y+1/2, z1/2; (iii) x+2, y, z+1; (iv) x, y+1/2, z+1/2.
 

Acknowledgements

We are grateful for support provided by the Chemical Sciences, Geosciences, and Biosciences Division, Office of Basic Energy Sciences, Office of Science, Heavy Elements Program, US Department of Energy, under grant DE–FG02-13ER16414.

References

First citationBruker (1999). SAINT and XPREP. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationBruker (2000). SMART. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationKohn, S. (1995). Terra Nova, 7, 554–556.  CrossRef Web of Science Google Scholar
First citationLin, Z.-E. & Yang, G.-Y. (2011). Eur. J. Inorg. Chem. 26, 3857–3867.  Web of Science CrossRef Google Scholar
First citationSheldrick, G. M. (1997). SADABS. University of Göttingen, Germany.  Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationWasserscheid, P. & Welton, T. (2003). In Ionic Liquids in Synthesis. Weinheim: VCH.  Google Scholar
First citationWestrip, S. P. (2010). J. Appl. Cryst. 43, 920–925.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 70| Part 2| February 2014| Pages o171-o172
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