8-Hy­droxy-5,7-dimethyl­quinolin-1-ium hydrogen sulfate

The quinoline ring system of the title salt, C₁₁H₁₂NO⁺·HSO₄⁻, is essentially planar, with a maximum deviation of 0.054 (2) Å for all non H atoms. In the crystal, the cations and anions are linked via N—H...O, O—H...O and weak C—H...O hydrogen bonds, and are stacked respectively in columns along the a axis. π–π stacking inter­actions, with centroid–centroid distances of 3.5473 (12) and 3.6926 (12) Å, are also observed. The crystal studied was an inversion twin with refined components of 0.43 (7):0.57 (7).

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.039
• wR factor = 0.103
• Data-to-parameter ratio = 18.8

checkCIF/PLATON results

No syntax errors found



Alert level C
STRVA01_ALERT_4_C           Flack test results are ambiguous.
           From the CIF: _refine_ls_abs_structure_Flack    0.430
           From the CIF: _refine_ls_abs_structure_Flack_su    0.070
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          1
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          3

Alert level G
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF          ?
PLAT033_ALERT_4_G Flack x Value Deviates .gt. 2*sigma from Zero ..      0.430
PLAT720_ALERT_4_G Number of Unusual/Non-Standard Labels ..........          3
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600          4

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   3 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   4 ALERT level G = General information/check it is not something unexpected

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   4 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

Recently, hydrogen-bonding patterns involving quinoline and its derivatives with organic acid have been investigated (Loh et al., 2010a,b). Syntheses of the quinoline derivatives were discussed earlier (Sasaki et al., 1998; Reux et al., 2009). Quinolines and their derivatives are very important compounds because of their wide occurrence in natural products (Morimoto et al., 1991) and biologically active compounds (Markees et al., 1970). Herein we report the synthesis of 8-hydroxy-5,7-dimethylquinolin-1-ium hydrogen sulfate.

The asymmetric unit of the title compound (Fig. 1) consists of one 8-hydroxy-5,7-dimethylquinolin-1-ium cation and one hydrogen sulfate anion. One proton is transferred from the hydroxyl group of sulfuric acid to the atom N1 of 8-hydroxy-5,7-dimethylquinoline during the crystallization, resulting in the formation of salt. The quinoline ring system (C1–C9/N1) is essentially planar with a maximum deviation of 0.054 (2) Å at atom C8. The bond lengths (Allen et al., 1987) and angles are normal.

In the crystal packing (Fig. 2), the cations are linked by the anions via intermolecular N1—H1N1···O3ⁱ, O5—H1O5···O2ⁱⁱ, O1—H1O1···O4ⁱ, C3—H3A···O5ⁱⁱⁱ and C11—H11C···O3ⁱⁱ hydrogen bonds (symmetry codes in Table 1) into a three-dimensional network. Furthermore, the crystal structure is stabilized by the following π–π interactions: (a) between pyridine (N1/C1–C5, centroid Cg1) and benzene (C1/C5–C9, centroid Cg2) rings Cg1···Cg2 (1/2 + x, 1/2 - y, 2 - z) 3.5473 (12) Å and (b) between benzene rings (C1/C5–C9, centroid Cg2) Cg2···Cg2 (-1/2 + x, 1/2 - y, 2 - z) 3.6926 (12) Å. The crystal studied was an inversion twin, with a ratio of the twin components of 0.43 (7):0.57 (7).

Related literature

For background to and the biological activity of quinoline derivatives, see: Sasaki et al. (1998); Reux et al. (2009); Morimoto et al. (1991); Markees et al. (1970). For related structures, see: Loh et al. (2010a,b). For bond-length data, see: Allen et al. (1987). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986).

S2. Experimental

A few drops of sulfuric acid were added to a hot methanol solution (20 ml) of 8-hydroxy-5,7-dimethylquinoline (36 mg, Aldrich) which had been warmed over a heating magnetic stirrer hotplate for a few minutes. The resulting solution was allowed to cool slowly at room temperature and crystals of the title compound (I) appeared after a few days.

S3. Refinement

O- and N-bound H atoms were located in a difference Fourier map and refined freely [refined distances: O—H = 0.97 (4) and 0.79 (3) Å, N—H = 0.91 (2) Å]. The remaining hydrogen atoms were positioned geometrically (C—H = 0.95–0.98 Å) and were refined using a riding model, with U_iso(H) = 1.2 U_eq(C) or 1.5U_eq(methyl C). A rotating-group model was used for the methyl group. The crystal studied was an inversion twin, with a ratio of the twin components of 0.43 (7):0.57 (7). The Hooft y parameter was 0.48 (4).

Computing details

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures

	Fig. 1. The molecular structure of the title compound with atom labels with 50% probability displacement ellipsoids.
	Fig. 2. The crystal packing of the title compound. The H atoms not involved in the intermolecular interactions (dashed lines) have been omitted for clarity.

8-Hydroxy-5,7-dimethylquinolin-1-ium hydrogen sulfate

Crystal data

C11H12NO^+·HSO4^−	F(000) = 568
Mr = 271.28	Dx = 1.567 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 6153 reflections
a = 6.6750 (9) Å	θ = 2.8–29.9°
b = 11.6952 (14) Å	µ = 0.30 mm^−1
c = 14.7283 (18) Å	T = 100 K
V = 1149.8 (3) Å^3	Block, yellow
Z = 4	0.41 × 0.17 × 0.15 mm

Data collection

Bruker APEXII DUO CCD area-detector diffractometer	3341 independent reflections
Radiation source: fine-focus sealed tube	3142 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.040
φ and ω scans	θmax = 30.0°, θmin = 2.8°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −9→9
Tmin = 0.889, Tmax = 0.956	k = −16→16
9735 measured reflections	l = −20→20

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.039	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.103	w = 1/[σ^2(Fo^2) + (0.0699P)^2 + 0.0691P] where P = (Fo^2 + 2Fc^2)/3
S = 1.05	(Δ/σ)max = 0.001
3341 reflections	Δρmax = 0.84 e Å^−3
178 parameters	Δρmin = −0.42 e Å^−3
0 restraints	Absolute structure: Flack (1983), 1410 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.43 (7)

Special details

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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 (Ų)

	x	y	z	Uiso*/Ueq
S1	0.15917 (7)	0.73295 (3)	0.89075 (3)	0.01680 (11)
O1	0.3784 (2)	0.68512 (11)	0.89220 (9)	0.0235 (3)
O2	0.0640 (3)	0.66640 (10)	0.82023 (10)	0.0284 (3)
O3	0.1707 (3)	0.85435 (10)	0.87008 (9)	0.0270 (3)
O4	0.0779 (3)	0.70976 (12)	0.98112 (10)	0.0307 (3)
O5	0.7154 (2)	0.37726 (9)	1.19245 (7)	0.0180 (3)
N1	0.7224 (2)	0.45539 (10)	1.01976 (9)	0.0145 (3)
C1	0.7217 (3)	0.33937 (12)	1.03458 (9)	0.0126 (3)
C2	0.7309 (3)	0.50147 (13)	0.93688 (10)	0.0165 (3)
H2A	0.7349	0.5822	0.9302	0.020*
C3	0.7339 (3)	0.43178 (14)	0.85994 (10)	0.0175 (3)
H3A	0.7394	0.4646	0.8010	0.021*
C4	0.7288 (3)	0.31450 (14)	0.87066 (9)	0.0158 (3)
H4A	0.7283	0.2665	0.8186	0.019*
C5	0.7243 (3)	0.26499 (13)	0.95828 (9)	0.0128 (3)
C6	0.7217 (3)	0.14410 (12)	0.97396 (10)	0.0138 (3)
C7	0.7275 (3)	0.10657 (13)	1.06266 (10)	0.0156 (3)
H7A	0.7291	0.0265	1.0733	0.019*
C8	0.7312 (3)	0.18055 (14)	1.13898 (10)	0.0151 (3)
C9	0.7197 (3)	0.29722 (12)	1.12470 (9)	0.0137 (3)
C10	0.7169 (3)	0.06073 (13)	0.89626 (11)	0.0189 (3)
H10A	0.7094	−0.0174	0.9201	0.028*
H10B	0.8388	0.0692	0.8598	0.028*
H10C	0.5994	0.0760	0.8583	0.028*
C11	0.7464 (3)	0.13120 (14)	1.23285 (11)	0.0203 (4)
H11A	0.8315	0.1804	1.2704	0.030*
H11B	0.8052	0.0545	1.2296	0.030*
H11C	0.6125	0.1264	1.2598	0.030*
H1N1	0.713 (4)	0.5064 (18)	1.0663 (15)	0.015 (5)*
H1O5	0.630 (5)	0.359 (2)	1.227 (2)	0.038 (8)*
H1O1	0.454 (6)	0.718 (3)	0.942 (2)	0.060 (10)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0199 (2)	0.01535 (16)	0.01516 (16)	0.00047 (15)	−0.00309 (16)	−0.00102 (12)
O1	0.0210 (7)	0.0244 (5)	0.0250 (6)	0.0039 (5)	0.0003 (6)	−0.0053 (5)
O2	0.0380 (9)	0.0183 (5)	0.0289 (6)	−0.0014 (6)	−0.0167 (7)	−0.0033 (5)
O3	0.0395 (9)	0.0146 (5)	0.0268 (6)	−0.0008 (6)	−0.0120 (6)	−0.0010 (4)
O4	0.0316 (8)	0.0373 (7)	0.0232 (6)	0.0046 (7)	0.0116 (6)	0.0026 (5)
O5	0.0252 (7)	0.0174 (5)	0.0113 (4)	−0.0031 (5)	0.0034 (5)	−0.0027 (4)
N1	0.0161 (7)	0.0135 (5)	0.0139 (5)	0.0003 (5)	0.0017 (5)	0.0007 (4)
C1	0.0130 (7)	0.0129 (6)	0.0120 (6)	0.0003 (6)	0.0007 (6)	0.0000 (5)
C2	0.0174 (8)	0.0151 (6)	0.0170 (6)	0.0011 (6)	0.0006 (7)	0.0044 (5)
C3	0.0179 (9)	0.0205 (7)	0.0142 (6)	−0.0002 (7)	0.0005 (7)	0.0039 (5)
C4	0.0169 (8)	0.0193 (6)	0.0112 (6)	−0.0002 (6)	0.0003 (6)	0.0004 (5)
C5	0.0125 (7)	0.0153 (6)	0.0107 (5)	0.0004 (6)	0.0000 (5)	−0.0002 (5)
C6	0.0136 (7)	0.0133 (6)	0.0146 (6)	0.0003 (6)	0.0005 (6)	−0.0020 (5)
C7	0.0151 (8)	0.0141 (6)	0.0177 (6)	0.0007 (6)	0.0018 (6)	0.0012 (5)
C8	0.0139 (8)	0.0180 (6)	0.0134 (6)	0.0006 (6)	0.0011 (6)	0.0016 (5)
C9	0.0159 (7)	0.0156 (6)	0.0098 (6)	−0.0014 (6)	−0.0005 (6)	−0.0008 (5)
C10	0.0219 (9)	0.0172 (6)	0.0176 (6)	−0.0010 (6)	0.0010 (7)	−0.0053 (5)
C11	0.0240 (10)	0.0219 (7)	0.0149 (6)	0.0038 (7)	0.0012 (7)	0.0067 (5)

Geometric parameters (Å, º)

S1—O2	1.4451 (13)	C4—C5	1.4148 (18)
S1—O3	1.4542 (12)	C4—H4A	0.9500
S1—O4	1.4626 (14)	C5—C6	1.433 (2)
S1—O1	1.5668 (15)	C6—C7	1.379 (2)
O1—H1O1	0.97 (4)	C6—C10	1.504 (2)
O5—C9	1.3685 (17)	C7—C8	1.419 (2)
O5—H1O5	0.79 (3)	C7—H7A	0.9500
N1—C2	1.3355 (18)	C8—C9	1.383 (2)
N1—C1	1.3743 (17)	C8—C11	1.502 (2)
N1—H1N1	0.91 (2)	C10—H10A	0.9800
C1—C9	1.4160 (18)	C10—H10B	0.9800
C1—C5	1.4212 (19)	C10—H10C	0.9800
C2—C3	1.396 (2)	C11—H11A	0.9800
C2—H2A	0.9500	C11—H11B	0.9800
C3—C4	1.381 (2)	C11—H11C	0.9800
C3—H3A	0.9500
O2—S1—O3	113.50 (8)	C1—C5—C6	118.45 (12)
O2—S1—O4	113.03 (10)	C7—C6—C5	117.81 (13)
O3—S1—O4	113.04 (8)	C7—C6—C10	121.01 (13)
O2—S1—O1	103.19 (8)	C5—C6—C10	121.17 (13)
O3—S1—O1	107.56 (9)	C6—C7—C8	123.86 (14)
O4—S1—O1	105.54 (9)	C6—C7—H7A	118.1
S1—O1—H1O1	111 (2)	C8—C7—H7A	118.1
C9—O5—H1O5	108 (2)	C9—C8—C7	118.70 (13)
C2—N1—C1	122.94 (13)	C9—C8—C11	121.54 (14)
C2—N1—H1N1	115.2 (14)	C7—C8—C11	119.75 (14)
C1—N1—H1N1	121.8 (14)	O5—C9—C8	124.42 (13)
N1—C1—C9	119.52 (13)	O5—C9—C1	116.46 (13)
N1—C1—C5	118.60 (13)	C8—C9—C1	119.05 (13)
C9—C1—C5	121.89 (13)	C6—C10—H10A	109.5
N1—C2—C3	120.46 (14)	C6—C10—H10B	109.5
N1—C2—H2A	119.8	H10A—C10—H10B	109.5
C3—C2—H2A	119.8	C6—C10—H10C	109.5
C4—C3—C2	119.12 (14)	H10A—C10—H10C	109.5
C4—C3—H3A	120.4	H10B—C10—H10C	109.5
C2—C3—H3A	120.4	C8—C11—H11A	109.5
C3—C4—C5	120.74 (13)	C8—C11—H11B	109.5
C3—C4—H4A	119.6	H11A—C11—H11B	109.5
C5—C4—H4A	119.6	C8—C11—H11C	109.5
C4—C5—C1	118.11 (13)	H11A—C11—H11C	109.5
C4—C5—C6	123.44 (13)	H11B—C11—H11C	109.5
C2—N1—C1—C9	177.73 (17)	C1—C5—C6—C10	177.83 (16)
C2—N1—C1—C5	−1.9 (3)	C5—C6—C7—C8	1.5 (3)
C1—N1—C2—C3	1.8 (3)	C10—C6—C7—C8	−179.68 (18)
N1—C2—C3—C4	−0.3 (3)	C6—C7—C8—C9	2.9 (3)
C2—C3—C4—C5	−1.2 (3)	C6—C7—C8—C11	−177.37 (18)
C3—C4—C5—C1	1.1 (3)	C7—C8—C9—O5	177.81 (17)
C3—C4—C5—C6	−179.12 (17)	C11—C8—C9—O5	−1.9 (3)
N1—C1—C5—C4	0.4 (2)	C7—C8—C9—C1	−5.3 (3)
C9—C1—C5—C4	−179.20 (17)	C11—C8—C9—C1	175.01 (17)
N1—C1—C5—C6	−179.41 (16)	N1—C1—C9—O5	1.0 (3)
C9—C1—C5—C6	1.0 (3)	C5—C1—C9—O5	−179.39 (16)
C4—C5—C6—C7	176.82 (17)	N1—C1—C9—C8	−176.17 (17)
C1—C5—C6—C7	−3.4 (3)	C5—C1—C9—C8	3.4 (3)
C4—C5—C6—C10	−2.0 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N1···O3^i	0.91 (2)	1.90 (2)	2.7753 (17)	161 (2)
O5—H1O5···O2^ii	0.79 (3)	1.91 (3)	2.698 (2)	172 (2)
O1—H1O1···O4^i	0.97 (4)	1.64 (4)	2.601 (2)	172 (3)
C3—H3A···O5^iii	0.95	2.46	3.3448 (19)	154
C11—H11C···O3^ii	0.98	2.50	3.445 (3)	161

Symmetry codes: (i) x+1/2, −y+3/2, −z+2; (ii) −x+1/2, −y+1, z+1/2; (iii) −x+3/2, −y+1, z−1/2.