8-Hy­droxy­quinolin-1-ium nitrate

In the title salt, C₉H₈NO⁺·NO₃⁻, the quinoline ring system is essentially planar with a maximum deviation of 0.043 (1) Å. In the crystal, an R₂²(7) ring motif is formed by inter­molecular N—H...O and C—H...O hydrogen bonds between the cation and the anion. In addition, inter­molecular O—H...O and C—H...O hydrogen bonds link the two ions, generating an R₂²(8) ring motif. These sets of ring motifs are further linked into a ribbon along the a axis via inter­molecular C—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.033
• wR factor = 0.095
• Data-to-parameter ratio = 13.7

checkCIF/PLATON results

No syntax errors found



Alert level C
SHFSU01_ALERT_2_C  Test not performed. _refine_ls_shift/su_max and
            _refine_ls_shift/esd_max not present.
            Absolute value of the parameter shift to su ratio given   0.001
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          2
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          3

Alert level G
PLAT720_ALERT_4_G Number of Unusual/Non-Standard Labels ..........          2

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 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
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   0 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,c,d). 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; Michael, 1997) and biologically active compounds (Markees et al., 1970; Campbell et al., 1988). Herein we report the synthesis of 8-hydroxyquinolin-1-ium nitrate.

The asymmetric unit of the title compound (Fig. 1) consists of one 8-hydroxyquinolin-1-ium cation (C1–C10/N1/N2) and one nitrate anion (O2–O4/N2). One proton is transferred from the hydroxyl group of nitric acid to the atom N1 of 8-hydroxyquinoline during the crystallization, resulting in the formation of salt. The quinoline ring system (C1–C9/N1) is approximately planar with a maximum deviation of 0.043 (1) Å at atom C4. Bond lengths (Allen et al., 1987) and angles are within the normal ranges and are comparable to the related structures (Loh et al., 2010a,b,c,d).

In the crystal packing (Fig. 2), R₂²(7) ring motifs are formed by intermolecular N1—H1N1···O4 and C2—H2A···O3 hydrogen bonds (Table 1). In addition, pairs of intermolecular O1—H1O1···O4 and C8—H8A···O2 hydrogen bonds (Table 1) link the cations and anions together to generate another set of R₂²(8) ring motifs. These sets of ring motifs are further linked into ribbons along the a axis via intermolecular C2—H2A···O3 hydrogen bonds (Table 1).

Related literature

For background to and the biological activity of quinoline derivatives, see: Campbell et al. (1988); Markees et al. (1970); Michael (1997); Morimoto et al. (1991); Reux et al. (2009); Sasaki et al. (1998). For related structures, see: Loh et al. (2010a,b,c,d). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986). For bond-length data, see: Allen et al. (1987).

S2. Experimental

A few drops of nitric acid were added to a hot methanol solution (20 ml) of 8-hydroxyquinoline (29 mg, Merck) which had been warmed over a magnetic stirrer hotplate for a few minutes. The resulting solution was allowed to cool slowly to room temperature. Crystals of the title compound appeared after a few days.

S3. Refinement

Atoms H1N1 and H1O1 were located from the difference Fourier map and were refined freely [N—H = 0.874 (18) Å and O—H = 0.86 (2) Å]. The remaining H atoms were positioned geometrically with the bond length of C—H being 0.93 Å and were refined using a riding model, with U_iso(H) = 1.2U_eq(C).

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 showing 50% probability displacement ellipsoids for non-H atoms and the atom-numbering scheme.
	Fig. 2. The crystal structure of the title compound, viewed along the b axis.

8-Hydroxyquinolin-1-ium nitrate

Crystal data

C9H8NO^+·NO3^−	F(000) = 432
Mr = 208.17	Dx = 1.602 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 5491 reflections
a = 11.3186 (2) Å	θ = 3.5–37.4°
b = 6.7568 (1) Å	µ = 0.13 mm^−1
c = 14.5006 (2) Å	T = 100 K
β = 128.882 (1)°	Block, colourless
V = 863.27 (2) Å^3	0.33 × 0.21 × 0.15 mm
Z = 4

Data collection

Bruker SMART APEXII CCD area-detector diffractometer	1978 independent reflections
Radiation source: fine-focus sealed tube	1754 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.023
φ and ω scans	θmax = 27.5°, θmin = 3.5°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −14→14
Tmin = 0.959, Tmax = 0.981	k = −8→8
9590 measured reflections	l = −18→18

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.095	H atoms treated by a mixture of independent and constrained refinement
S = 1.08	w = 1/[σ^2(Fo^2) + (0.0472P)^2 + 0.3584P] where P = (Fo^2 + 2Fc^2)/3
1978 reflections	(Δ/σ)max < 0.001
144 parameters	Δρmax = 0.39 e Å^−3
0 restraints	Δρmin = −0.22 e Å^−3

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
O1	0.07908 (9)	0.09986 (13)	0.12784 (7)	0.0167 (2)
N1	−0.13600 (11)	0.10475 (14)	0.15595 (8)	0.0139 (2)
C1	0.01506 (13)	0.11333 (16)	0.25398 (10)	0.0138 (2)
C2	−0.24612 (13)	0.10646 (17)	0.16438 (10)	0.0163 (2)
H2A	−0.3465	0.0953	0.0961	0.020*
C3	−0.21344 (13)	0.12476 (17)	0.27446 (10)	0.0171 (2)
H3A	−0.2913	0.1279	0.2795	0.021*
C4	−0.06498 (13)	0.13802 (17)	0.37464 (10)	0.0158 (2)
H4A	−0.0424	0.1546	0.4479	0.019*
C5	0.05450 (13)	0.12672 (16)	0.36803 (10)	0.0144 (2)
C6	0.21000 (13)	0.12812 (17)	0.46913 (10)	0.0171 (2)
H6A	0.2383	0.1339	0.5447	0.020*
C7	0.31841 (13)	0.12080 (18)	0.45453 (10)	0.0186 (3)
H7A	0.4204	0.1209	0.5210	0.022*
C8	0.27878 (13)	0.11312 (18)	0.34078 (11)	0.0177 (2)
H8A	0.3547	0.1114	0.3334	0.021*
C9	0.12859 (13)	0.10813 (16)	0.24054 (10)	0.0148 (2)
O2	0.52824 (10)	0.47945 (18)	0.24518 (8)	0.0321 (3)
O3	0.53907 (10)	0.42125 (15)	0.39694 (8)	0.0239 (2)
O4	0.74765 (9)	0.44023 (13)	0.41965 (7)	0.0179 (2)
N2	0.60151 (11)	0.44742 (16)	0.35208 (9)	0.0177 (2)
H1N1	−0.1627 (19)	0.091 (2)	0.0852 (16)	0.028 (4)*
H1O1	0.145 (2)	0.056 (3)	0.1211 (17)	0.042 (5)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0159 (4)	0.0230 (4)	0.0140 (4)	0.0024 (3)	0.0108 (3)	0.0012 (3)
N1	0.0159 (5)	0.0145 (5)	0.0124 (4)	0.0001 (4)	0.0095 (4)	−0.0002 (3)
C1	0.0161 (5)	0.0114 (5)	0.0137 (5)	0.0003 (4)	0.0094 (4)	0.0003 (4)
C2	0.0153 (5)	0.0169 (5)	0.0167 (5)	−0.0007 (4)	0.0100 (4)	−0.0008 (4)
C3	0.0189 (5)	0.0183 (6)	0.0200 (5)	−0.0007 (4)	0.0150 (5)	−0.0012 (4)
C4	0.0216 (6)	0.0138 (5)	0.0150 (5)	0.0000 (4)	0.0130 (5)	−0.0003 (4)
C5	0.0183 (5)	0.0114 (5)	0.0146 (5)	−0.0001 (4)	0.0108 (5)	0.0000 (4)
C6	0.0198 (5)	0.0163 (5)	0.0133 (5)	0.0006 (4)	0.0095 (5)	−0.0004 (4)
C7	0.0152 (5)	0.0191 (6)	0.0160 (5)	0.0010 (4)	0.0071 (4)	−0.0004 (4)
C8	0.0163 (5)	0.0186 (6)	0.0203 (6)	0.0008 (4)	0.0126 (5)	0.0003 (4)
C9	0.0184 (5)	0.0132 (5)	0.0147 (5)	0.0010 (4)	0.0113 (5)	0.0010 (4)
O2	0.0186 (4)	0.0607 (7)	0.0157 (4)	0.0030 (4)	0.0101 (4)	0.0078 (4)
O3	0.0169 (4)	0.0395 (5)	0.0197 (4)	−0.0012 (4)	0.0137 (4)	0.0007 (4)
O4	0.0121 (4)	0.0260 (5)	0.0155 (4)	0.0000 (3)	0.0087 (3)	−0.0005 (3)
N2	0.0141 (4)	0.0238 (5)	0.0159 (5)	0.0002 (4)	0.0098 (4)	−0.0006 (4)

Geometric parameters (Å, º)

O1—C9	1.3558 (13)	C4—H4A	0.9300
O1—H1O1	0.86 (2)	C5—C6	1.4170 (15)
N1—C2	1.3266 (15)	C6—C7	1.3707 (16)
N1—C1	1.3770 (14)	C6—H6A	0.9300
N1—H1N1	0.874 (18)	C7—C8	1.4126 (16)
C1—C9	1.4160 (16)	C7—H7A	0.9300
C1—C5	1.4196 (15)	C8—C9	1.3790 (16)
C2—C3	1.3995 (16)	C8—H8A	0.9300
C2—H2A	0.9300	O2—N2	1.2343 (13)
C3—C4	1.3701 (16)	O3—N2	1.2372 (13)
C3—H3A	0.9300	O4—N2	1.2899 (12)
C4—C5	1.4166 (16)
C9—O1—H1O1	114.7 (13)	C4—C5—C1	117.82 (10)
C2—N1—C1	122.28 (10)	C6—C5—C1	118.93 (10)
C2—N1—H1N1	117.2 (11)	C7—C6—C5	119.40 (10)
C1—N1—H1N1	120.5 (11)	C7—C6—H6A	120.3
N1—C1—C9	120.19 (10)	C5—C6—H6A	120.3
N1—C1—C5	118.95 (10)	C6—C7—C8	121.52 (11)
C9—C1—C5	120.86 (10)	C6—C7—H7A	119.2
N1—C2—C3	120.99 (10)	C8—C7—H7A	119.2
N1—C2—H2A	119.5	C9—C8—C7	120.63 (11)
C3—C2—H2A	119.5	C9—C8—H8A	119.7
C4—C3—C2	119.03 (10)	C7—C8—H8A	119.7
C4—C3—H3A	120.5	O1—C9—C8	125.09 (10)
C2—C3—H3A	120.5	O1—C9—C1	116.28 (10)
C3—C4—C5	120.81 (10)	C8—C9—C1	118.62 (10)
C3—C4—H4A	119.6	O2—N2—O3	122.01 (10)
C5—C4—H4A	119.6	O2—N2—O4	119.39 (9)
C4—C5—C6	123.24 (10)	O3—N2—O4	118.60 (9)
C2—N1—C1—C9	179.06 (10)	C4—C5—C6—C7	−178.64 (11)
C2—N1—C1—C5	−0.72 (16)	C1—C5—C6—C7	1.38 (16)
C1—N1—C2—C3	2.44 (17)	C5—C6—C7—C8	0.40 (18)
N1—C2—C3—C4	−0.98 (17)	C6—C7—C8—C9	−1.52 (18)
C2—C3—C4—C5	−2.14 (17)	C7—C8—C9—O1	−179.71 (11)
C3—C4—C5—C6	−176.26 (11)	C7—C8—C9—C1	0.77 (17)
C3—C4—C5—C1	3.72 (16)	N1—C1—C9—O1	1.69 (15)
N1—C1—C5—C4	−2.31 (15)	C5—C1—C9—O1	−178.53 (10)
C9—C1—C5—C4	177.91 (10)	N1—C1—C9—C8	−178.75 (10)
N1—C1—C5—C6	177.67 (10)	C5—C1—C9—C8	1.03 (16)
C9—C1—C5—C6	−2.11 (16)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N1···O4^i	0.874 (18)	1.944 (18)	2.8112 (12)	171.6 (15)
O1—H1O1···O4^ii	0.86 (3)	1.83 (3)	2.6794 (16)	169 (2)
C2—H2A···O3^iii	0.93	2.53	3.106 (2)	120
C2—H2A···O3^i	0.93	2.31	3.0247 (14)	133
C8—H8A···O2^ii	0.93	2.40	3.249 (2)	152

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