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Acta Cryst. (2007). E63, m1727-m1728    [ doi:10.1107/S160053680702418X ]

Bis(8-methylquinolinium) tetrabromidoferrate(III) bromide

R. Kruszynski, D. Wyrzykowski and L. Chmurzynski

Abstract top

The asymmetric unit of the title compound, (C10H10N)2[FeBr4]Br, contains two protonated 8-methylquinolinium cations, one bromide anion and one tetrabromidoferrate anion. The mean Fe-Br distance is 2.3338 (6) Å. The 8-methylquinolinium cations are planar and are inclined at a dihedral angle of 5.25 (9)° with respect to each other. The two 8-methylquinolinium cations and bromide anion are connected via N-H...Br hydrogen bonds. Furthermore, there are short C-H...Br contacts and [pi]...[pi] stacking interactions between cations. The N-H...Br hydrogen bonds link the molecules into chains along the [210] direction.

Comment top

The composition of quinolinium and methylquinolinium tetrahalogenoferrates(III) has been found to be distinctly dependent on location of the methyl substituent in the quinoline ring and the kind of halide ligands in the coordination sphere of Fe(III) (Warnke et al., 2003). When a quinolinum cation is a counter-ion, both the [FeBr4]- and [FeCl4]- anions form binary (1:1) salts (Wyrzykowski, Sikorski, Konitz et al., 2006). With a 2-methyl substituted quinolinium cation, resulting salts have a composition of (2MeQH)2[FeX4]X (where 2MeQH is 2-methylquinolinum cation, and X = Br or Cl) (Warnke et al., 2006; Wyrzykowski, Sikorski, Lis et al., 2006). Introduction of the 2-methylquinoline substituted at position 4 by —NH2 leads again to formation of 1:1 salt (Wyrzykowski, Warnke et al., 2006). Thus determining the composition of FeBr4 complex containing quinoline methylated at another position was interesting, and in future can lead to general conclusions about influence of quinoline substituents on complex composition.

All 8-methylquinolinium cations intramolecular distances and angles in (I) (Fig. 1) can be considered normal. All atoms lie in general positions. The asymmetric unit contains two protonated 8-methylquinolinium cations, one bromide anion and one tetrabromoferrate anion. The mean Fe—Br distance is 2.3338 (6) Å. Two Br—Fe—Br angles are smaller than tetrahedral, two are almost tetrahedral, and two are greater than tetrahedral. The 8-methylquinolinium cations can be considered planar and are inclined at 5.25 (9)°. From weighted least-squares planes calculated through all non-hydrogen atoms of the cations the most deviating atoms are C7 [0.025 (3) Å] in one molecule and C14 [0.026 (3) Å] in the second molecule. The two 8-methylquinolinium cations and bromide anion are connected via N—H···Br hydrogen bonds (Table 1, Fig. 2). In the structure can be found one more intermolecular C—H···Br short contact (Table 2), which, according to Desiraju & Steiner (1999), can be considered as a weak hydrogen bond. The cations are associated via π···π stacking interactions (Table 2) to dimers, and dimers are separated by anions one form each other. Thus, in considered structure, tetrabromoferrate anions play role of stacking breaker. The N—H···Br hydrogen bonds link the molecules to a chain running along [2 1 0] (Fig. 2).

Related literature top

For details of other tetrahalogenoferrates with quinoline and its derivatives, see: Bottomley et al. (1984), Warnke et al. (2006), Wyrzykowski, Sikorski, Konitz et al. (2006), Wyrzykowski, Sikorski, Lis et al. (2006), Wyrzykowski, Warnke et al. (2006); and for similar tetrahalogenoferrates with aromatic amines acting as balancing cations see: Abboud et al. (2005), Barbaro et al. (1992), Chan & Baird (2004), Couce et al. (1995), Daran et al. (1979), James et al. (2001), James et al. (1982), Khan et al. (1987), Lowe et al. (1990), Lowe et al. (1994), Hackert & Jacobson (1971), Podesta & Orpen (2005), Shaviv et al. (1992), Veidis et al. (1979), Veidis et al. (1981), Zora et al. (1990), Zordan et al. (2005). For general synthesis procedures see: Warnke et al. (2003).

For related literature, see: Desiraju & Steiner (1999).

For related literature, see: Hackert & Jacobson (1971).

Experimental top

To a solution of FeBr3 (ca 0.025 mol) in ethanol (96%) (50 ml), a stoichiometric quantity of a 40% HBr solution and 8-methylquinoline (ca 0.025 mol) were added in turn. The compound crystallized directly from the reaction mixture at ambient temperature. After ca 3 months dark-red crystals appeared. The compound was dried over P4O10 in a vacuum desiccator. Elemental analysis (calculated/found %): C 32.38/32.28, H 2.69/2.66, N 3.77/3.80, Br 53.74/53.54, Fe 7.51/7.28.

Refinement top

The carbon-bonded hydrogen atoms were placed in calculated positions and were refined as riding on adjacent carbon atom with fixed U values [Uiso(H) = 1.2Ueq(C) or Uiso(H) = 1.5Ueq(C-methyl)]. The methyl groups were allowed to rotate about their local threefold axis (AFIX 137). The nitrogen-bonded hydrogen atoms were founded from difference Fourier synthesis after eight cycles of anisotropic refinement and were refined as riding on adjacent nitrogen atom with fixed U values (Uiso(H) = 1.2Ueq(N).

Computing details top

Data collection: CrysAlis CCD v. 1.163 (UNIL IC & KUMA 2000); cell refinement: CrysAlis RED v. 1.163 (UNIL IC & KUMA 2000); data reduction: CrysAlis RED v. 1.163; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP in SHELXTL/PC (Sheldrick, 1990b) ORTEP-3 W v. 1.062 (Farrugia 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997) and PLATON (Spek, 1990).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound (I). Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. A part of the molecular packing of the title compound showing short intermolecular interactions (hydrogen bonds are indicated by dashed lines).
Bis(8-methylquinolinium) tetrabromidoferrate(III) bromide top
Crystal data top
(C10H10N)2[FeBr4]BrZ = 2
Mr = 743.78F(000) = 710
Triclinic, P1Dx = 2.007 Mg m−3
Dm = 2.01 Mg m−3
Dm measured by Berman density torsion balance
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.9533 (5) ÅCell parameters from 7884 reflections
b = 10.3853 (4) Åθ = 5–20°
c = 15.2432 (8) ŵ = 8.74 mm−1
α = 84.781 (4)°T = 291 K
β = 79.645 (5)°Plate, orange
γ = 85.556 (4)°0.38 × 0.11 × 0.03 mm
V = 1231.00 (11) Å3
Data collection top
Kuma KM4-CCD
diffractometer		4345 independent reflections
Radiation source: fine-focus sealed tube3120 reflections with I > 2σ(I)
graphiteRint = 0.020
Detector resolution: 1048576 pixels mm-1θmax = 25.1°, θmin = 2.0°
ω scansh = −8→9
Absorption correction: numerical
X-RED. STOE & Cie (1999)		k = −12→12
Tmin = 0.321, Tmax = 0.780l = −16→18
12314 measured reflections
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)] = 0.023Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.057H-atom parameters constrained
S = 0.98 w = 1/[σ2(Fo2) + (0.0304P)2]
where P = (Fo2 + 2Fc2)/3
4345 reflections(Δ/σ)max = 0.001
255 parametersΔρmax = 0.43 e Å−3
0 restraintsΔρmin = −0.57 e Å−3
Crystal data top
(C10H10N)2[FeBr4]Brγ = 85.556 (4)°
Mr = 743.78V = 1231.00 (11) Å3
Triclinic, P1Z = 2
a = 7.9533 (5) ÅMo Kα radiation
b = 10.3853 (4) ŵ = 8.74 mm−1
c = 15.2432 (8) ÅT = 291 K
α = 84.781 (4)°0.38 × 0.11 × 0.03 mm
β = 79.645 (5)°
Data collection top
Kuma KM4-CCD
diffractometer		4345 independent reflections
Absorption correction: numerical
X-RED. STOE & Cie (1999)		3120 reflections with I > 2σ(I)
Tmin = 0.321, Tmax = 0.780Rint = 0.020
12314 measured reflectionsθmax = 25.1°
Refinement top
R[F2 > 2σ(F2)] = 0.023H-atom parameters constrained
wR(F2) = 0.057Δρmax = 0.43 e Å−3
S = 0.98Δρmin = −0.57 e Å−3
4345 reflectionsAbsolute structure: ?
255 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 > 2σ(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
Fe10.84814 (6)0.24354 (4)0.12389 (3)0.04493 (13)
Br10.82953 (4)0.02568 (3)0.10380 (2)0.05566 (11)
Br21.10108 (4)0.31300 (3)0.03423 (2)0.05990 (11)
Br40.61015 (5)0.36204 (4)0.08073 (3)0.06862 (13)
Br50.86151 (6)0.26018 (5)0.27339 (3)0.08107 (14)
N10.4142 (3)1.0191 (2)0.24958 (17)0.0491 (7)
H1N0.43001.07080.29580.059*
C10.3428 (4)1.0733 (3)0.1817 (2)0.0580 (9)
H10.29621.15820.18320.070*
C20.3373 (4)1.0048 (4)0.1094 (2)0.0654 (10)
H20.28771.04300.06170.078*
C30.4047 (4)0.8812 (4)0.1083 (2)0.0610 (10)
H30.40100.83480.05940.073*
C40.4800 (4)0.8217 (3)0.1789 (2)0.0498 (8)
C50.4844 (4)0.8946 (3)0.2527 (2)0.0461 (8)
C60.5485 (4)0.6941 (4)0.1818 (3)0.0634 (10)
H60.54880.64450.13400.076*
C70.6143 (5)0.6420 (4)0.2538 (3)0.0780 (13)
H70.65630.55590.25570.094*
C80.6205 (4)0.7161 (4)0.3261 (3)0.0680 (11)
H80.66850.67820.37430.082*
C90.5574 (4)0.8425 (3)0.3269 (2)0.0543 (9)
C100.5637 (5)0.9234 (4)0.4024 (2)0.0799 (12)
H10A0.61540.87240.44740.120*
H10B0.44950.95310.42770.120*
H10C0.63010.99660.38040.120*
N110.1901 (3)0.5284 (2)0.31091 (18)0.0494 (7)
H11N0.23980.45740.34730.059*
C110.1751 (4)0.5010 (3)0.2300 (2)0.0581 (9)
H110.21040.41880.21160.070*
C120.1075 (5)0.5929 (3)0.1723 (3)0.0648 (10)
H120.09670.57320.11530.078*
C130.0573 (4)0.7127 (3)0.2003 (2)0.0603 (9)
H130.01070.77500.16220.072*
C140.0747 (4)0.7440 (3)0.2859 (2)0.0502 (8)
C150.1451 (4)0.6474 (3)0.3433 (2)0.0456 (8)
C160.0312 (5)0.8670 (4)0.3157 (3)0.0669 (10)
H16−0.01460.93200.27920.080*
C170.0557 (5)0.8919 (4)0.3977 (3)0.0823 (12)
H170.02740.97440.41720.099*
C180.1232 (5)0.7949 (4)0.4539 (3)0.0826 (13)
H180.13670.81460.51050.099*
C190.1701 (4)0.6718 (3)0.4288 (2)0.0624 (10)
C200.2449 (5)0.5689 (4)0.4901 (2)0.0845 (13)
H20A0.26440.60690.54220.127*
H20B0.35140.53260.45910.127*
H20C0.16630.50180.50780.127*
Br990.31991 (6)0.24911 (4)0.38250 (3)0.08361 (16)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Fe10.0569 (3)0.0382 (3)0.0423 (3)0.0022 (2)−0.0162 (2)−0.0065 (2)
Br10.0671 (2)0.03822 (19)0.0643 (2)−0.00061 (16)−0.01844 (18)−0.00616 (16)
Br20.0676 (2)0.0539 (2)0.0579 (2)−0.00829 (17)−0.01148 (18)0.00184 (17)
Br40.0731 (3)0.0532 (2)0.0841 (3)0.01958 (18)−0.0308 (2)−0.0154 (2)
Br50.1119 (3)0.0926 (3)0.0433 (2)−0.0105 (3)−0.0195 (2)−0.0148 (2)
N10.0650 (17)0.0445 (16)0.0415 (16)0.0087 (13)−0.0197 (14)−0.0121 (13)
C10.068 (2)0.049 (2)0.058 (2)0.0062 (17)−0.0183 (19)−0.0016 (18)
C20.075 (3)0.076 (3)0.050 (2)−0.005 (2)−0.0211 (19)−0.009 (2)
C30.068 (2)0.076 (3)0.044 (2)−0.012 (2)−0.0102 (18)−0.0240 (19)
C40.049 (2)0.050 (2)0.050 (2)−0.0086 (16)−0.0003 (16)−0.0152 (17)
C50.052 (2)0.0398 (19)0.046 (2)0.0022 (15)−0.0082 (16)−0.0071 (15)
C60.059 (2)0.048 (2)0.081 (3)−0.0017 (18)0.002 (2)−0.022 (2)
C70.070 (3)0.036 (2)0.120 (4)0.0106 (18)0.004 (3)−0.014 (2)
C80.066 (2)0.056 (2)0.076 (3)0.0125 (19)−0.009 (2)0.005 (2)
C90.060 (2)0.048 (2)0.053 (2)0.0083 (17)−0.0103 (18)−0.0062 (17)
C100.103 (3)0.088 (3)0.055 (3)0.018 (2)−0.038 (2)−0.009 (2)
N110.0596 (17)0.0384 (15)0.0500 (18)0.0000 (13)−0.0139 (14)0.0033 (13)
C110.081 (3)0.042 (2)0.058 (2)−0.0044 (17)−0.026 (2)−0.0095 (17)
C120.095 (3)0.052 (2)0.056 (2)−0.009 (2)−0.036 (2)0.0004 (18)
C130.071 (2)0.048 (2)0.065 (3)0.0004 (18)−0.029 (2)0.0077 (18)
C140.052 (2)0.045 (2)0.053 (2)0.0009 (16)−0.0101 (17)−0.0005 (16)
C150.0498 (19)0.0401 (19)0.045 (2)0.0051 (15)−0.0052 (15)−0.0038 (15)
C160.079 (3)0.053 (2)0.062 (3)0.0169 (19)−0.004 (2)−0.0021 (19)
C170.110 (3)0.058 (3)0.072 (3)0.022 (2)0.000 (2)−0.020 (2)
C180.120 (3)0.074 (3)0.049 (2)0.023 (3)−0.007 (2)−0.021 (2)
C190.078 (3)0.056 (2)0.049 (2)0.0091 (19)−0.0057 (19)−0.0054 (18)
C200.128 (4)0.077 (3)0.052 (2)0.016 (3)−0.032 (2)−0.006 (2)
Br990.1428 (4)0.0520 (2)0.0567 (3)0.0362 (2)−0.0337 (3)−0.01146 (19)
Geometric parameters (Å, °) top
Fe1—Br52.3230 (6)C10—H10B0.9600
Fe1—Br12.3300 (5)C10—H10C0.9600
Fe1—Br42.3387 (5)N11—C111.318 (4)
Fe1—Br22.3436 (6)N11—C151.370 (4)
N1—C11.329 (4)N11—H11N0.9828
N1—C51.368 (4)C11—C121.383 (4)
N1—H1N0.9551C11—H110.9300
C1—C21.374 (4)C12—C131.359 (5)
C1—H10.9300C12—H120.9300
C2—C31.353 (5)C13—C141.405 (5)
C2—H20.9300C13—H130.9300
C3—C41.398 (5)C14—C161.393 (4)
C3—H30.9300C14—C151.420 (4)
C4—C61.393 (5)C15—C191.401 (4)
C4—C51.418 (4)C16—C171.350 (5)
C5—C91.410 (4)C16—H160.9300
C6—C71.351 (5)C17—C181.401 (5)
C6—H60.9300C17—H170.9300
C7—C81.409 (5)C18—C191.373 (5)
C7—H70.9300C18—H180.9300
C8—C91.369 (5)C19—C201.512 (5)
C8—H80.9300C20—H20A0.9600
C9—C101.494 (5)C20—H20B0.9600
C10—H10A0.9600C20—H20C0.9600
Br5—Fe1—Br1107.92 (2)C9—C10—H10C109.5
Br5—Fe1—Br4112.12 (2)H10A—C10—H10C109.5
Br1—Fe1—Br4108.87 (2)H10B—C10—H10C109.5
Br5—Fe1—Br2109.50 (2)C11—N11—C15123.8 (3)
Br1—Fe1—Br2107.98 (2)C11—N11—H11N115.3
Br4—Fe1—Br2110.33 (2)C15—N11—H11N120.9
C1—N1—C5123.2 (3)N11—C11—C12120.8 (3)
C1—N1—H1N119.6N11—C11—H11119.6
C5—N1—H1N116.8C12—C11—H11119.6
N1—C1—C2120.5 (3)C13—C12—C11118.7 (3)
N1—C1—H1119.8C13—C12—H12120.6
C2—C1—H1119.8C11—C12—H12120.6
C3—C2—C1119.2 (3)C12—C13—C14121.1 (3)
C3—C2—H2120.4C12—C13—H13119.5
C1—C2—H2120.4C14—C13—H13119.5
C2—C3—C4121.5 (3)C16—C14—C13122.8 (3)
C2—C3—H3119.2C16—C14—C15118.5 (3)
C4—C3—H3119.2C13—C14—C15118.7 (3)
C6—C4—C3123.8 (3)N11—C15—C19121.0 (3)
C6—C4—C5118.0 (3)N11—C15—C14116.8 (3)
C3—C4—C5118.2 (3)C19—C15—C14122.1 (3)
N1—C5—C9120.5 (3)C17—C16—C14119.9 (4)
N1—C5—C4117.4 (3)C17—C16—H16120.0
C9—C5—C4122.1 (3)C14—C16—H16120.0
C7—C6—C4120.3 (3)C16—C17—C18120.8 (4)
C7—C6—H6119.8C16—C17—H17119.6
C4—C6—H6119.8C18—C17—H17119.6
C6—C7—C8121.1 (3)C19—C18—C17122.5 (4)
C6—C7—H7119.4C19—C18—H18118.7
C8—C7—H7119.4C17—C18—H18118.7
C9—C8—C7121.4 (4)C18—C19—C15116.2 (3)
C9—C8—H8119.3C18—C19—C20121.7 (4)
C7—C8—H8119.3C15—C19—C20122.1 (3)
C8—C9—C5116.9 (3)C19—C20—H20A109.5
C8—C9—C10122.5 (3)C19—C20—H20B109.5
C5—C9—C10120.6 (3)H20A—C20—H20B109.5
C9—C10—H10A109.5C19—C20—H20C109.5
C9—C10—H10B109.5H20A—C20—H20C109.5
H10A—C10—H10B109.5H20B—C20—H20C109.5
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···Br99i0.962.393.229 (2)146
N11—H11N···Br990.982.253.168 (3)155
C10—H10A···Br99ii0.962.893.819 (4)163
Symmetry codes: (i) x, y+1, z; (ii) −x+1, −y+1, −z+1.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···Br99i0.962.393.229 (2)146
N11—H11N···Br990.982.253.168 (3)155
C10—H10A···Br99ii0.962.893.819 (4)163
Symmetry codes: (i) x, y+1, z; (ii) −x+1, −y+1, −z+1.
Table 2
Stacking interactions geometry, distances in Å, angles in °. Cg(Z) means six-membered ring containing Z atom. top
Cg(I)···Cg(J)Cg···CgαβγCg(I)pCg(J)p
Cg(N1)···Cg(C19)3.89705.1625.2530.363.3633.525
Cg(C9)···Cg(N11)3.81305.1426.1921.423.5503.421
Cg(C9)···Cg(C19)3.70894.1417.9617.243.5423.528
Cg···Cg - distance between ring centroids, α - dihedral Angle between Planes I and J, β - angle between Cg(I)-->Cg(J) vector and normal to plane I, γ - angle between Cg(I)-->Cg(J) vector and normal to plane J, Cg(I)p perpendicular distance of Cg(I) on ring J, Cg(J)p perpendicular distance of Cg(J) on ring I.
Acknowledgements top

This work was supported by the Polish State Committee for Scientific Research (grant No. DS/8230–4–0088–7). The crystallographic part was financed by funds allocated by the Ministry of Science and Higher Education to the Institute of General and Ecological Chemistry, Technical University of Łódź. Poland.

references
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