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Acta Cryst. (2007). E63, m2279-m2280    [ doi:10.1107/S1600536807037555 ]

Bis(8-methylquinolinium) tetrachloridoferrate(III) chloride

R. Kruszynski, D. Wyrzykowski, E. Styczen and L. Chmurzynski

Abstract top

The asymmetric unit of the title compound, (C10H10N)2[FeCl4]Cl, contains two protonated 8-methylquinolinium cations, one chloride anion and one tetrachloridoferrate(III) anion. The mean Fe-Cl distance is 2.1880 (7) Å. The two 8-methylquinolinium cations and chloride anion are connected via N-H...Cl hydrogen bonds. Furthermore, there are stacking interactions between cations. N-H...Cl hydrogen bonds link two 8-methylquinolinium cations. The bromido analogue is isostructural with the title compound.

Comment top

The composition of quinolinium and methylquinolinium tetrahalogenoferrates(III) has been found to be distinctly dependent on the 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 (MeQH), resulting salts have a composition of (2MeQH)2[FeX4]X (where X = Br or Cl) (Warnke et al., 2006; Wyrzykowski, Sikorski, Lis et al., 2006). Introduction of the 2-methylquinolie substituted at position 4 by —NH2 leads again to formation of 1:1 salt (Wyrzykowski, Warnke et al., 2006). The 8-methylquinolie forms (8MeQH)2[FeBr4]Br salt (Kruszynski et al., 2007). Generally in compounds containing aromatic amines acting as balancing cations, replacing the FeBr4 anions by FeCl4 anions leads to isostructural compounds: (2MeQH)2[FeX4]X (Warnke et al., 2006; Wyrzykowski, Sikorski, Lis et al., 2006), (4ClpyH)3(FeX4)2X (where 4ClpyH means 4-chloropyridinium) (Lowe et al., 1990; Zordan et al., 2005), but cases of non-isostructurality are also known: (pyH)3(FeX4)2X (where pyH means pyridinium) (Shaviv et al., 1992; Lowe et al., 1994). For some compounds, salts with different composition are found for FeCl4 anions: (pyH)5(FeX4)2X3 (James et al., 1982). Thus determining the composition of FeCl4 complex containing quinoline methylated at position 8 was undertaken.

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 chloride anion and one tetrachloroferrate anion. The mean Fe—Cl distance is 2.1880 (7) Å. Four Cl—Fe—Cl angles are smaller than tetrahedral and and two are greater than tetrahedral one. The 8-methylquinolinium cations can be considered planar and are inclined at 4.71 (7)°. From weighted last squares planes calculated through all non-hydrogen atoms of cations the most deviate atom C10 (about 0.018 (2) Å) in one molecule and C14 (about 0.018 (2) Å) in second molecule. The two 8-methylquinolinium cations and chloride anion are connected via N—H···Cl···H—N hydrogen bonds (Table 2, Fig. 2). The cations are associated via π···π stacking interactions (Table 2) to dimers, and dimers are separated by anions from each other. Thus, in the considered structure, tetrachloroferrate anions play the role of a stacking breaker. The N—H···Cl···H—N hydrogen bonds together with π···π stacking interactions expands molecules to the seminifinite chain along crystallographic b axis (Fig. 2).

Related literature top

For the bromo analogue, see: Kruszynski et al. (2007). 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, 1982), Khan et al. (1987); Lowe et al. (1990, 1994); Hackert & Jacobson (1971); Podesta & Orpen (2005); Shaviv et al. (1992); Veidis et al. (1979, 1981); Zora et al. (1990); Zordan et al. (2005). For general synthesis procedures, see: Warnke et al. (2003).

Experimental top

The synthesis of the title compound was carried out using a procedure similar to that previously reported for the preparation of bis(8-methylquinolinium) tetrabromidoferrate(III) bromide (Kruszynski et al., 2007). To a solution of FeCl3 (ca 0.05 mol) in ethanol (96%) (25 ml), a stoichiometric quantity of a 12 mol/dm3 HCl solution and 8-methylquinoline (ca 0.05 mol) were added in turn. After 7 days the title compound precipitated. It was recrystallized from ethanol at ambient temperature. After 2 days yellow crystals appeared. The compound was dried over P4O10 in a vacuum desiccator. Elemental analysis (calculated/found %): C 46.04/46.36, H 3.84/3.82, N 5.37/5.17, Cl 34.05/33.85, Fe 10.71/10.52.

Refinement top

The carbon-bonded hydrogen atoms were placed in calculated positions and were refined as riding on adjacent carbon atom with Uiso(H) = 1.2Ueq(C-non-methyl) and 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 found from difference Fourier synthesis after eight cycles of anisotropic refinement and were refined as riding on adjacent nitrogen atom with Uiso(H) = 1.2Ueq(N).

Computing details top

Data collection: CrysAlis CCD (UNIL IC & Kuma, 2000); cell refinement: CrysAlis RED (UNIL IC & Kuma, 2000); data reduction: CrysAlis RED; 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) and ORTEP-3 (Windows Version 1.062; Farrugia 1997); software used to prepare material for publication: SHELXL97 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) tetrachloridoferrate(III) chloride top
Crystal data top
(C10H10N)2[FeCl4]ClZ = 2
Mr = 521.48F000 = 530
Triclinic, P1Dx = 1.497 Mg m−3
Dm = 1.50 Mg m−3
Dm measured by Berman density torsion balance
Hall symbol: -P 1Mo Kα radiation
λ = 0.71073 Å
a = 7.9065 (3) ÅCell parameters from 6196 reflections
b = 10.1445 (3) Åθ = 5–20º
c = 14.8518 (6) ŵ = 1.24 mm−1
α = 84.097 (3)ºT = 291.0 (3) K
β = 78.200 (3)ºNeedle, yellow
γ = 84.869 (2)º0.38 × 0.10 × 0.06 mm
V = 1157.00 (7) Å3
Data collection top
Kuma KM-4-CCD
diffractometer		4101 independent reflections
Radiation source: fine-focus sealed tube3257 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.039
Detector resolution: 1048576 pixels mm-1θmax = 25.1º
T = 291.0(3) Kθmin = 2.0º
ω scansh = −9→8
Absorption correction: numerical
(X-RED; Stoe & Cie, 1999)		k = −12→12
Tmin = 0.861, Tmax = 0.919l = −16→17
11265 measured reflections
Refinement top
Refinement on F2Secondary atom site location: structure-invariant direct methods
Least-squares matrix: fullHydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.029H-atom parameters constrained
wR(F2) = 0.086  w = 1/[σ2(Fo2) + (0.0487P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.09(Δ/σ)max = 0.001
4101 reflectionsΔρmax = 0.33 e Å−3
255 parametersΔρmin = −0.29 e Å−3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
(C10H10N)2[FeCl4]Clγ = 84.869 (2)º
Mr = 521.48V = 1157.00 (7) Å3
Triclinic, P1Z = 2
a = 7.9065 (3) ÅMo Kα
b = 10.1445 (3) ŵ = 1.24 mm−1
c = 14.8518 (6) ÅT = 291.0 (3) K
α = 84.097 (3)º0.38 × 0.10 × 0.06 mm
β = 78.200 (3)º
Data collection top
Kuma KM-4-CCD
diffractometer		4101 independent reflections
Absorption correction: numerical
(X-RED; Stoe & Cie, 1999)		3257 reflections with I > 2σ(I)
Tmin = 0.861, Tmax = 0.919Rint = 0.039
11265 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.029255 parameters
wR(F2) = 0.086H-atom parameters constrained
S = 1.09Δρmax = 0.33 e Å−3
4101 reflectionsΔρmin = −0.29 e Å−3
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 > 2sigma(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
Fe10.84101 (4)0.23561 (3)0.128413 (19)0.04951 (12)
Cl10.82335 (8)0.02684 (6)0.10945 (4)0.06251 (17)
Cl21.08019 (8)0.30260 (6)0.03856 (4)0.06542 (18)
Cl40.61592 (9)0.35139 (7)0.08881 (5)0.0759 (2)
Cl50.85692 (11)0.25261 (9)0.27133 (4)0.0882 (2)
N10.3990 (2)1.01488 (17)0.24864 (11)0.0513 (4)
H1N0.39351.06900.29830.062*
C10.3282 (3)1.0698 (2)0.17910 (15)0.0606 (6)
H10.27761.15610.18100.073*
C20.3285 (3)1.0010 (3)0.10422 (16)0.0685 (7)
H20.27831.03980.05560.082*
C30.4035 (3)0.8752 (3)0.10222 (15)0.0622 (6)
H30.40570.82840.05130.075*
C40.4772 (3)0.8150 (2)0.17530 (14)0.0523 (5)
C50.4737 (3)0.8883 (2)0.25102 (13)0.0450 (5)
C60.5517 (3)0.6842 (2)0.17673 (19)0.0650 (6)
H60.55590.63420.12710.078*
C70.6166 (3)0.6318 (3)0.2500 (2)0.0772 (8)
H70.66450.54470.25120.093*
C80.6136 (3)0.7065 (3)0.32554 (19)0.0678 (7)
H80.66090.66740.37510.081*
C90.5436 (3)0.8341 (2)0.32818 (15)0.0554 (5)
C100.5423 (4)0.9154 (3)0.40664 (16)0.0757 (8)
H10A0.58910.86180.45410.114*
H10B0.42540.94690.43110.114*
H10C0.61130.98970.38510.114*
N110.1904 (2)0.51280 (17)0.30506 (11)0.0500 (4)
H11N0.23800.44490.34290.060*
C110.1783 (3)0.4871 (2)0.22141 (15)0.0580 (6)
H110.21650.40370.20130.070*
C120.1095 (3)0.5828 (2)0.16336 (16)0.0628 (6)
H120.10220.56490.10420.075*
C130.0529 (3)0.7029 (2)0.19396 (15)0.0569 (6)
H130.00340.76710.15590.068*
C140.0673 (3)0.7326 (2)0.28227 (14)0.0476 (5)
C150.1394 (3)0.6330 (2)0.33969 (13)0.0446 (5)
C160.0135 (3)0.8566 (2)0.31588 (17)0.0628 (6)
H16−0.03480.92360.27930.075*
C170.0315 (4)0.8789 (3)0.40055 (18)0.0784 (8)
H17−0.00320.96190.42220.094*
C180.1020 (4)0.7788 (3)0.45683 (17)0.0718 (7)
H180.11040.79660.51590.086*
C190.1590 (3)0.6560 (2)0.42852 (14)0.0551 (6)
C200.2383 (4)0.5506 (3)0.48932 (16)0.0733 (7)
H20A0.24920.58690.54490.110*
H20B0.35070.52010.45720.110*
H20C0.16550.47740.50470.110*
Cl990.31343 (11)0.23929 (7)0.37586 (4)0.0810 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Fe10.0657 (2)0.04101 (19)0.04674 (18)0.00170 (14)−0.02298 (14)−0.00737 (12)
Cl10.0779 (4)0.0394 (3)0.0755 (4)−0.0032 (3)−0.0279 (3)−0.0049 (2)
Cl20.0801 (4)0.0563 (4)0.0618 (3)−0.0113 (3)−0.0194 (3)0.0021 (3)
Cl40.0841 (4)0.0607 (4)0.0900 (4)0.0244 (3)−0.0386 (3)−0.0223 (3)
Cl50.1168 (6)0.1058 (6)0.0494 (3)−0.0085 (5)−0.0284 (3)−0.0168 (3)
N10.0686 (12)0.0436 (10)0.0443 (9)0.0053 (9)−0.0179 (8)−0.0098 (7)
C10.0774 (16)0.0508 (14)0.0555 (13)0.0066 (12)−0.0240 (11)−0.0008 (10)
C20.0866 (18)0.0747 (19)0.0501 (13)−0.0060 (14)−0.0285 (12)−0.0023 (12)
C30.0740 (16)0.0723 (18)0.0451 (12)−0.0168 (13)−0.0116 (11)−0.0174 (11)
C40.0558 (13)0.0501 (13)0.0516 (12)−0.0104 (10)−0.0034 (10)−0.0151 (10)
C50.0508 (12)0.0401 (11)0.0438 (10)0.0006 (9)−0.0080 (9)−0.0081 (8)
C60.0631 (15)0.0507 (15)0.0796 (16)−0.0018 (12)−0.0019 (12)−0.0236 (12)
C70.0704 (17)0.0424 (14)0.113 (2)0.0083 (12)−0.0048 (15)−0.0156 (14)
C80.0660 (15)0.0542 (15)0.0826 (17)0.0083 (12)−0.0233 (13)0.0032 (13)
C90.0637 (14)0.0481 (13)0.0549 (12)0.0059 (11)−0.0173 (10)−0.0043 (10)
C100.102 (2)0.0740 (18)0.0588 (14)0.0181 (15)−0.0408 (13)−0.0118 (12)
N110.0620 (11)0.0394 (10)0.0502 (10)−0.0013 (8)−0.0195 (8)0.0031 (7)
C110.0800 (16)0.0412 (12)0.0568 (13)−0.0017 (11)−0.0220 (11)−0.0081 (10)
C120.0945 (18)0.0470 (14)0.0544 (13)−0.0078 (12)−0.0313 (12)−0.0029 (10)
C130.0705 (15)0.0488 (13)0.0553 (13)−0.0043 (11)−0.0266 (11)0.0064 (10)
C140.0494 (12)0.0410 (12)0.0528 (11)−0.0007 (9)−0.0139 (9)0.0004 (9)
C150.0478 (11)0.0398 (11)0.0448 (11)−0.0007 (9)−0.0080 (8)−0.0012 (8)
C160.0712 (16)0.0481 (14)0.0681 (15)0.0134 (11)−0.0199 (12)−0.0037 (11)
C170.101 (2)0.0611 (17)0.0747 (17)0.0241 (15)−0.0230 (15)−0.0260 (13)
C180.095 (2)0.0710 (18)0.0510 (13)0.0126 (15)−0.0188 (12)−0.0174 (12)
C190.0646 (14)0.0540 (14)0.0460 (11)0.0038 (11)−0.0134 (10)−0.0026 (10)
C200.103 (2)0.0677 (17)0.0531 (13)0.0077 (15)−0.0325 (13)−0.0006 (12)
Cl990.1340 (6)0.0521 (4)0.0576 (3)0.0333 (4)−0.0340 (4)−0.0127 (3)
Geometric parameters (Å, °) top
Fe1—Cl52.1770 (7)C10—H10B0.9600
Fe1—Cl12.1853 (7)C10—H10C0.9600
Fe1—Cl42.1921 (7)N11—C111.319 (3)
Fe1—Cl22.1977 (7)N11—C151.368 (3)
N1—C11.324 (3)N11—H11N0.9444
N1—C51.365 (3)C11—C121.381 (3)
N1—H1N0.9560C11—H110.9300
C1—C21.372 (3)C12—C131.351 (3)
C1—H10.9300C12—H120.9300
C2—C31.358 (4)C13—C141.404 (3)
C2—H20.9300C13—H130.9300
C3—C41.396 (3)C14—C161.401 (3)
C3—H30.9300C14—C151.411 (3)
C4—C61.403 (3)C15—C191.404 (3)
C4—C51.405 (3)C16—C171.338 (3)
C5—C91.413 (3)C16—H160.9300
C6—C71.338 (4)C17—C181.399 (4)
C6—H60.9300C17—H170.9300
C7—C81.412 (4)C18—C191.364 (3)
C7—H70.9300C18—H180.9300
C8—C91.362 (3)C19—C201.505 (3)
C8—H80.9300C20—H20A0.9600
C9—C101.493 (3)C20—H20B0.9600
C10—H10A0.9600C20—H20C0.9600
Cl5—Fe1—Cl1108.91 (3)C9—C10—H10C109.5
Cl5—Fe1—Cl4112.49 (3)H10A—C10—H10C109.5
Cl1—Fe1—Cl4108.72 (3)H10B—C10—H10C109.5
Cl5—Fe1—Cl2108.64 (3)C11—N11—C15123.54 (18)
Cl1—Fe1—Cl2108.12 (3)C11—N11—H11N118.3
Cl4—Fe1—Cl2109.85 (3)C15—N11—H11N118.2
C1—N1—C5122.81 (19)N11—C11—C12120.6 (2)
C1—N1—H1N115.9N11—C11—H11119.7
C5—N1—H1N121.3C12—C11—H11119.7
N1—C1—C2120.8 (2)C13—C12—C11119.0 (2)
N1—C1—H1119.6C13—C12—H12120.5
C2—C1—H1119.6C11—C12—H12120.5
C3—C2—C1118.9 (2)C12—C13—C14121.1 (2)
C3—C2—H2120.5C12—C13—H13119.4
C1—C2—H2120.5C14—C13—H13119.4
C2—C3—C4121.1 (2)C16—C14—C13122.9 (2)
C2—C3—H3119.4C16—C14—C15118.5 (2)
C4—C3—H3119.4C13—C14—C15118.6 (2)
C3—C4—C6122.7 (2)N11—C15—C19121.17 (18)
C3—C4—C5118.3 (2)N11—C15—C14117.16 (18)
C6—C4—C5118.9 (2)C19—C15—C14121.67 (19)
N1—C5—C4117.97 (19)C17—C16—C14120.0 (2)
N1—C5—C9120.19 (19)C17—C16—H16120.0
C4—C5—C9121.8 (2)C14—C16—H16120.0
C7—C6—C4119.5 (2)C16—C17—C18120.7 (2)
C7—C6—H6120.2C16—C17—H17119.7
C4—C6—H6120.2C18—C17—H17119.7
C6—C7—C8121.2 (2)C19—C18—C17122.6 (2)
C6—C7—H7119.4C19—C18—H18118.7
C8—C7—H7119.4C17—C18—H18118.7
C9—C8—C7122.1 (2)C18—C19—C15116.5 (2)
C9—C8—H8118.9C18—C19—C20121.8 (2)
C7—C8—H8118.9C15—C19—C20121.7 (2)
C8—C9—C5116.4 (2)C19—C20—H20A109.5
C8—C9—C10122.8 (2)C19—C20—H20B109.5
C5—C9—C10120.7 (2)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···Cl99i0.962.153.0490 (18)156
N11—H11N···Cl990.942.153.0143 (18)151
Symmetry codes: (i) x, y+1, z.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···Cl99i0.962.153.0490 (18)156
N11—H11N···Cl990.942.153.0143 (18)151
Symmetry codes: (i) x, y+1, z.
Geometry of stacking interactions (Å, °). top
Cg(I)···Cg(J)Cg···CgαβγCg(I)pCg(J)p
Cg(N1)···Cg(C19)3.86765.1024.5429.633.3623.518
Cg(C9)···Cg(N11)3.80444.4926.3022.233.5223.411
Cg(C9)···Cg(C19)3.71214.0318.9318.863.5133.511
Cg(Z) is the centroid of the six-membered ring containing atom Z. Cg···Cg is the distance between ring centroids, α is the dihedral angle between planes I and J, β is the angle between the Cg(I)–Cg(J) vector and the normal to plane I, γ is the angle between the Cg(I)–Cg(J) vector and the normal to plane J, Cg(I)p is the perpendicular distance of Cg(I) from ring J and Cg(J)p is the perpendicular distance of Cg(J) from ring I.
Acknowledgements top

This work was supported by the Polish State Committee for Scientific Research (grant No. DS/8232–4–0088–7). 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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