supplementary materials


su2369 scheme

Acta Cryst. (2012). E68, m292-m293    [ doi:10.1107/S160053681200517X ]

catena-Poly[1-butyl-3-methylimidazolium [[dichlorido(methanol-[kappa]O)(propan-2-ol-[kappa]O)lanthanate(III)]-di-[mu]-chlorido]]

Y. Han, F. Dai, A. G. Sykes, P. S. May, M. T. Berry, Q. Meng and C. Lin

Abstract top

The title compound, (C8H15N2)[LaCl4(CH3OH)(C3H7OH)], consists of one 1-butyl-3-methylimidazolium (BMI+) cation and one hexahedral tetrachlorido(methanol)(propan-2-ol)lanthanate anion. The LaIII ion is eight-coordinate, with the LaIII ion bridged by a pair of Cl atoms, so forming chains propagating along the a-axis direction. Each LaIII ion is further coordinated by two isolated Cl atoms, one methanol and one propan-2-ol molecule. The coordinated methanol and propan-2-ol molecules of the anion form O-H...Cl hydrogen bonds with the Cl atoms of inversion-related anions. The BMI+ cation froms C-H...Cl hydrogen bonds with the Cl atoms of the anion. The anions are located in the C faces of the triclinic unit cell, with an inversion center in the middle of the La2Cl2 ring of the polymeric chain.

Comment top

Ionic liquids (ILs) have received considerable attention due to their extraordinary properties as solvents (Binnemans, 2007). They have been proposed as excellent alternatives to conventional solvents for luminescent lanthanide complexes. Compared with aqueous or organic solvents, ILs have the advantages of potentially excluding quenching oscillators, providing greater luminescence quantum yields (Brandner et al., 2011; Samikkanu et al., 2007). Some analogous structures to the title compound, tris(1-ethyl-3-methylimidazolium)hexabromidoeuropate(III) (Pellens et al., 2008) and tris(1-ethyl-3-methylimidazolium)hexachloridolanthanate(III) (Matsumoto et al., 2002) have been reported.

The title compound, in contrast to these examples, includes coordinated alcohol molecules and crystallized after mixing lanthanum chloride in 1-butyl-3-methylimidazolium chloride (BMICl) with a mixture of methanol and propan-2-ol (Fig. 1). The bond lengths between La and the two non-bridging Cl atoms are 2.8232 (5) Å and 2.838 (1) Å, respectively. The La to bridging Cl distances are in the range of 2.8884 (6) Å and 3.0021 (8) Å. All the Cl atoms, except Cl4, exhibit short contacts to neighboring H atoms on the imidazolium rings or on alcohol molecules ranging from 2.653 Å to 2.909 Å.

In the crystal, H atoms in the imidazolium cations, such as H5A and H8A, form hydrogen bonds with chlorine Cl3 (Fig. 2 and Table 1). The two H atoms in methanol (H2B) and propan-2-ol (H1D) form hydrogen bonds with atoms Cl2 and Cl1, respectively (Table 1). The [LaCl4(CH3OH)(i-C3H9OH)]- anions are centered in the C faces of the triclinic unit cell, with an inversion center in the middle of La2Cl2 ring, as shown in Fig. 3. The BMI+ cation is on an inversion center, at position (1/2, 1/2, 1/2) in the unit cell.

Related literature top

For related crystal structures, see: Binnemans (2007); Pellens et al. (2008); Matsumoto et al. (2002). For the synthesis of the title compound, see: Burrell et al. (2007). For the optical properties of lanthanides in ionic liquids, see: Brandner et al. (2011); Samikkanu et al. (2007).

Experimental top

1-butyl-3-methylimidazolium chloride (BMICl) was synthesized following a method reported by Burrell et al. (2007). Lanthanum chloride heptahydrate (0.708 g, 1.906 mmol) was mixed with BMICl (1.000 g, 5.725 mmol) in a small vial in a glove box. Equal amount of methanol and propan-2-ol were added carefully until the total dissolution of the mixture. The vial was sealed and a colourless crystal appeared after cooling at 258 K for three weeks.

Refinement top

The OH H atoms were located in a difference Fourier map and were freely refined. The C-bound H atoms were included in calculated positions and treated as riding atoms: C—H = 0.98, 0.97 and 0.96 Å for CH, CH2 and CH3 H-atoms, respectively, with Uiso(H) = k × Ueq(parent C-atom), where k = 1.5 for CH3 H atoms and k = 1.2 for all other H atoms.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of the asymmetric unit of the title compound, with the numbering scheme and displacement ellipsoids drawn at the 50% probability level. H atoms have been omitted for clarify.
[Figure 2] Fig. 2. A view of the molecular structure of the title compound, with the dashed lines denoting the hydrogen bonding.
[Figure 3] Fig. 3. Crystal packing of the title compound viewed along the a axis. The [LaCl4(CH3OH)(i-C3H9OH)]- anions are located about the inversion centers in the C faces of the triclinic unit cell.
catena-Poly[1-butyl-3-methylimidazolium [[dichlorido(methanol- κO)(propan-2-ol-κO)lanthanate(III)]-di-µ-chlorido]] top
Crystal data top
(C8H15N2)[LaCl4(CH4O)(C3H8O)]Z = 2
Mr = 512.07F(000) = 508
Triclinic, P1Dx = 1.674 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 9.5035 (6) ÅCell parameters from 8208 reflections
b = 10.7413 (6) Åθ = 2.3–26.4°
c = 11.8625 (7) ŵ = 2.63 mm1
α = 114.009 (1)°T = 100 K
β = 109.735 (1)°Block, colourless
γ = 92.857 (1)°0.30 × 0.15 × 0.05 mm
V = 1016.20 (10) Å3
Data collection top
Bruker APEXII CCD area-detector
diffractometer
4155 independent reflections
Radiation source: fine-focus sealed tube3780 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.029
φ and ω scansθmax = 26.4°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1111
Tmin = 0.506, Tmax = 0.880k = 1313
11178 measured reflectionsl = 1414
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)] = 0.022Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.049H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.0193P)2 + 0.4077P]
where P = (Fo2 + 2Fc2)/3
4155 reflections(Δ/σ)max = 0.001
198 parametersΔρmax = 0.71 e Å3
0 restraintsΔρmin = 0.59 e Å3
Crystal data top
(C8H15N2)[LaCl4(CH4O)(C3H8O)]γ = 92.857 (1)°
Mr = 512.07V = 1016.20 (10) Å3
Triclinic, P1Z = 2
a = 9.5035 (6) ÅMo Kα radiation
b = 10.7413 (6) ŵ = 2.63 mm1
c = 11.8625 (7) ÅT = 100 K
α = 114.009 (1)°0.30 × 0.15 × 0.05 mm
β = 109.735 (1)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
4155 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
3780 reflections with I > 2σ(I)
Tmin = 0.506, Tmax = 0.880Rint = 0.029
11178 measured reflectionsθmax = 26.4°
Refinement top
R[F2 > 2σ(F2)] = 0.022H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.049Δρmax = 0.71 e Å3
S = 1.04Δρmin = 0.59 e Å3
4155 reflectionsAbsolute structure: ?
198 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
La10.739307 (15)0.491237 (15)0.023339 (14)0.00964 (5)
Cl10.54404 (7)0.24123 (7)0.24214 (6)0.01713 (14)
Cl20.77665 (7)0.64602 (7)0.16020 (7)0.01686 (14)
Cl31.05144 (7)0.63430 (7)0.15869 (6)0.01356 (13)
Cl40.56003 (7)0.42798 (7)0.11059 (6)0.01393 (13)
O10.8605 (2)0.3297 (2)0.0650 (2)0.0176 (4)
H1D0.951 (4)0.344 (4)0.096 (4)0.042 (11)*
O20.7406 (2)0.7145 (2)0.16709 (19)0.0169 (4)
H2B0.668 (4)0.710 (4)0.180 (4)0.040 (12)*
N10.6581 (2)0.1728 (2)0.4667 (2)0.0145 (5)
N20.6359 (2)0.3591 (2)0.4388 (2)0.0148 (5)
C10.7807 (3)0.8505 (3)0.1784 (3)0.0253 (7)
H1A0.77340.91960.25770.038*
H1B0.71180.85650.10100.038*
H1C0.88370.86660.18410.038*
C20.7981 (3)0.1900 (3)0.0376 (3)0.0218 (6)
H2A0.68640.17660.00480.026*
C30.8374 (3)0.0814 (3)0.0713 (3)0.0297 (7)
H3A0.79930.09410.15090.045*
H3B0.79110.01040.09070.045*
H3C0.94650.09180.04090.045*
C40.8534 (4)0.1779 (4)0.1663 (3)0.0335 (8)
H4A0.82550.24880.23100.050*
H4B0.96280.18970.20010.050*
H4C0.80730.08750.15020.050*
C50.6982 (3)0.3114 (3)0.5278 (3)0.0152 (6)
H5A0.75990.36620.61800.018*
C60.5659 (3)0.1306 (3)0.3339 (3)0.0188 (6)
H6A0.52140.03890.26860.023*
C70.5522 (3)0.2461 (3)0.3163 (3)0.0195 (6)
H7A0.49670.24920.23650.023*
C80.7080 (3)0.0804 (3)0.5284 (3)0.0168 (6)
H8A0.77130.13560.62190.025*
H8B0.76540.02200.48470.025*
H8C0.61990.02320.51910.025*
C90.6552 (3)0.5071 (3)0.4667 (3)0.0167 (6)
H9A0.64950.56160.55260.020*
H9B0.57120.51670.39860.020*
C100.8046 (3)0.5662 (3)0.4693 (3)0.0175 (6)
H10A0.81130.51360.38330.021*
H10B0.88990.55850.53780.021*
C110.8133 (3)0.7191 (3)0.4988 (3)0.0199 (6)
H11A0.81190.77170.58690.024*
H11B0.72380.72640.43350.024*
C120.9580 (3)0.7831 (3)0.4944 (3)0.0250 (7)
H12A0.95880.87900.51350.038*
H12B0.95880.73250.40680.038*
H12C1.04690.77780.56010.038*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
La10.00730 (8)0.00983 (8)0.01066 (8)0.00150 (5)0.00309 (6)0.00398 (6)
Cl10.0115 (3)0.0139 (3)0.0183 (3)0.0012 (2)0.0051 (3)0.0010 (3)
Cl20.0131 (3)0.0205 (4)0.0221 (3)0.0054 (3)0.0073 (3)0.0138 (3)
Cl30.0089 (3)0.0143 (3)0.0129 (3)0.0018 (2)0.0032 (2)0.0029 (3)
Cl40.0113 (3)0.0179 (3)0.0158 (3)0.0046 (2)0.0060 (2)0.0099 (3)
O10.0107 (10)0.0165 (10)0.0292 (11)0.0036 (8)0.0068 (9)0.0143 (9)
O20.0120 (10)0.0131 (10)0.0206 (11)0.0001 (8)0.0072 (8)0.0027 (8)
N10.0128 (11)0.0147 (12)0.0153 (11)0.0024 (9)0.0057 (9)0.0061 (10)
N20.0118 (11)0.0168 (12)0.0173 (12)0.0046 (9)0.0077 (9)0.0073 (10)
C10.0278 (16)0.0136 (15)0.0324 (18)0.0036 (12)0.0152 (14)0.0059 (13)
C20.0188 (14)0.0170 (15)0.0346 (17)0.0055 (12)0.0112 (13)0.0156 (14)
C30.0246 (16)0.0244 (17)0.0350 (19)0.0063 (13)0.0079 (14)0.0117 (15)
C40.041 (2)0.0298 (19)0.038 (2)0.0069 (15)0.0174 (16)0.0215 (16)
C50.0124 (13)0.0172 (14)0.0124 (13)0.0032 (11)0.0039 (10)0.0042 (11)
C60.0169 (14)0.0161 (15)0.0153 (14)0.0017 (11)0.0034 (11)0.0023 (12)
C70.0173 (14)0.0205 (15)0.0132 (14)0.0036 (11)0.0013 (11)0.0045 (12)
C80.0179 (14)0.0158 (14)0.0165 (14)0.0034 (11)0.0080 (11)0.0061 (12)
C90.0163 (14)0.0162 (14)0.0207 (15)0.0066 (11)0.0081 (11)0.0102 (12)
C100.0136 (13)0.0188 (15)0.0173 (14)0.0029 (11)0.0052 (11)0.0065 (12)
C110.0174 (14)0.0189 (15)0.0231 (15)0.0046 (11)0.0066 (12)0.0101 (13)
C120.0231 (15)0.0249 (17)0.0271 (17)0.0023 (13)0.0089 (13)0.0128 (14)
Geometric parameters (Å, º) top
La1—O12.5102 (19)C3—H3A0.9600
La1—O22.5348 (19)C3—H3B0.9600
La1—Cl12.8232 (6)C3—H3C0.9600
La1—Cl22.8378 (7)C4—H4A0.9600
La1—Cl32.8884 (6)C4—H4B0.9600
La1—Cl42.9119 (6)C4—H4C0.9600
La1—Cl4i2.9841 (6)C5—H5A0.9300
La1—Cl3ii3.0021 (6)C6—C71.346 (4)
Cl3—La1ii3.0021 (6)C6—H6A0.9300
Cl4—La1i2.9841 (6)C7—H7A0.9300
O1—C21.446 (3)C8—H8A0.9600
O1—H1D0.79 (4)C8—H8B0.9600
O2—C11.431 (3)C8—H8C0.9600
O2—H2B0.75 (4)C9—C101.512 (4)
N1—C51.329 (3)C9—H9A0.9700
N1—C61.378 (3)C9—H9B0.9700
N1—C81.466 (3)C10—C111.525 (4)
N2—C51.332 (3)C10—H10A0.9700
N2—C71.381 (3)C10—H10B0.9700
N2—C91.474 (3)C11—C121.533 (4)
C1—H1A0.9600C11—H11A0.9700
C1—H1B0.9600C11—H11B0.9700
C1—H1C0.9600C12—H12A0.9600
C2—C41.500 (4)C12—H12B0.9600
C2—C31.520 (4)C12—H12C0.9600
C2—H2A0.9800
O1—La1—O2110.49 (6)C3—C2—H2A107.9
O1—La1—Cl183.72 (5)C2—C3—H3A109.5
O2—La1—Cl1142.48 (5)C2—C3—H3B109.5
O1—La1—Cl2141.74 (5)H3A—C3—H3B109.5
O2—La1—Cl289.42 (5)C2—C3—H3C109.5
Cl1—La1—Cl2100.30 (2)H3A—C3—H3C109.5
O1—La1—Cl372.67 (5)H3B—C3—H3C109.5
O2—La1—Cl370.43 (5)C2—C4—H4A109.5
Cl1—La1—Cl3146.015 (18)C2—C4—H4B109.5
Cl2—La1—Cl384.745 (19)H4A—C4—H4B109.5
O1—La1—Cl472.72 (5)C2—C4—H4C109.5
O2—La1—Cl470.12 (5)H4A—C4—H4C109.5
Cl1—La1—Cl482.364 (19)H4B—C4—H4C109.5
Cl2—La1—Cl4145.479 (18)N1—C5—N2109.0 (2)
Cl3—La1—Cl4112.230 (18)N1—C5—H5A125.5
O1—La1—Cl4i141.39 (5)N2—C5—H5A125.5
O2—La1—Cl4i71.22 (5)C7—C6—N1107.5 (2)
Cl1—La1—Cl4i76.418 (18)C7—C6—H6A126.3
Cl2—La1—Cl4i75.142 (17)N1—C6—H6A126.3
Cl3—La1—Cl4i136.524 (19)C6—C7—N2107.1 (2)
Cl4—La1—Cl4i72.078 (19)C6—C7—H7A126.5
O1—La1—Cl3ii70.16 (5)N2—C7—H7A126.5
O2—La1—Cl3ii139.40 (5)N1—C8—H8A109.5
Cl1—La1—Cl3ii77.752 (18)N1—C8—H8B109.5
Cl2—La1—Cl3ii73.582 (18)H8A—C8—H8B109.5
Cl3—La1—Cl3ii71.48 (2)N1—C8—H8C109.5
Cl4—La1—Cl3ii139.352 (18)H8A—C8—H8C109.5
Cl4i—La1—Cl3ii134.605 (17)H8B—C8—H8C109.5
La1—Cl3—La1ii108.52 (2)N2—C9—C10113.7 (2)
La1—Cl4—La1i107.922 (19)N2—C9—H9A108.8
C2—O1—La1130.59 (16)C10—C9—H9A108.8
C2—O1—H1D109 (3)N2—C9—H9B108.8
La1—O1—H1D118 (3)C10—C9—H9B108.8
C1—O2—La1123.48 (17)H9A—C9—H9B107.7
C1—O2—H2B108 (3)C9—C10—C11109.5 (2)
La1—O2—H2B112 (3)C9—C10—H10A109.8
C5—N1—C6108.2 (2)C11—C10—H10A109.8
C5—N1—C8125.9 (2)C9—C10—H10B109.8
C6—N1—C8125.8 (2)C11—C10—H10B109.8
C5—N2—C7108.2 (2)H10A—C10—H10B108.2
C5—N2—C9125.7 (2)C10—C11—C12112.2 (2)
C7—N2—C9126.1 (2)C10—C11—H11A109.2
O2—C1—H1A109.5C12—C11—H11A109.2
O2—C1—H1B109.5C10—C11—H11B109.2
H1A—C1—H1B109.5C12—C11—H11B109.2
O2—C1—H1C109.5H11A—C11—H11B107.9
H1A—C1—H1C109.5C11—C12—H12A109.5
H1B—C1—H1C109.5C11—C12—H12B109.5
O1—C2—C4108.9 (2)H12A—C12—H12B109.5
O1—C2—C3110.9 (2)C11—C12—H12C109.5
C4—C2—C3113.2 (3)H12A—C12—H12C109.5
O1—C2—H2A107.9H12B—C12—H12C109.5
C4—C2—H2A107.9
O1—La1—Cl3—La1ii74.31 (5)Cl1—La1—O2—C1116.57 (19)
O2—La1—Cl3—La1ii165.68 (5)Cl2—La1—O2—C110.28 (19)
Cl1—La1—Cl3—La1ii26.22 (4)Cl3—La1—O2—C174.35 (19)
Cl2—La1—Cl3—La1ii74.42 (2)Cl4—La1—O2—C1161.9 (2)
Cl4—La1—Cl3—La1ii136.68 (2)Cl4i—La1—O2—C184.77 (19)
Cl4i—La1—Cl3—La1ii136.31 (2)Cl3ii—La1—O2—C153.2 (2)
Cl3ii—La1—Cl3—La1ii0.0La1—O1—C2—C4139.1 (2)
O1—La1—Cl4—La1i163.89 (5)La1—O1—C2—C395.8 (2)
O2—La1—Cl4—La1i75.95 (5)C6—N1—C5—N20.4 (3)
Cl1—La1—Cl4—La1i78.13 (2)C8—N1—C5—N2177.5 (2)
Cl2—La1—Cl4—La1i18.96 (4)C7—N2—C5—N10.3 (3)
Cl3—La1—Cl4—La1i133.77 (2)C9—N2—C5—N1178.9 (2)
Cl4i—La1—Cl4—La1i0.0C5—N1—C6—C70.4 (3)
Cl3ii—La1—Cl4—La1i139.14 (2)C8—N1—C6—C7177.5 (2)
O2—La1—O1—C2119.5 (2)N1—C6—C7—N20.2 (3)
Cl1—La1—O1—C224.7 (2)C5—N2—C7—C60.0 (3)
Cl2—La1—O1—C2123.36 (19)C9—N2—C7—C6179.1 (2)
Cl3—La1—O1—C2179.9 (2)C5—N2—C9—C1080.0 (3)
Cl4—La1—O1—C259.3 (2)C7—N2—C9—C1099.1 (3)
Cl4i—La1—O1—C234.2 (2)N2—C9—C10—C11180.0 (2)
Cl3ii—La1—O1—C2103.9 (2)C9—C10—C11—C12176.5 (2)
O1—La1—O2—C1136.28 (19)
Symmetry codes: (i) x+1, y+1, z; (ii) x+2, y+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1D···Cl2ii0.79 (4)2.42 (4)3.206 (2)171 (4)
O2—H2B···Cl1i0.75 (4)2.39 (4)3.122 (2)166 (4)
C5—H5A···Cl3iii0.932.653.458 (3)145
C8—H8A···Cl3iii0.962.673.565 (3)156
Symmetry codes: (i) x+1, y+1, z; (ii) x+2, y+1, z; (iii) x+2, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1D···Cl2i0.79 (4)2.42 (4)3.206 (2)171 (4)
O2—H2B···Cl1ii0.75 (4)2.39 (4)3.122 (2)166 (4)
C5—H5A···Cl3iii0.932.653.458 (3)145.2
C8—H8A···Cl3iii0.962.673.565 (3)156.0
Symmetry codes: (i) x+2, y+1, z; (ii) x+1, y+1, z; (iii) x+2, y+1, z+1.
Acknowledgements top

The authors thank the National Science Foundation/EPSCoR (grant No. 0554609) and the State of South Dakota, Governor's Office of Economic Development, for financial support.

references
References top

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