4-Carboxy­pyridazin-1-ium chloride

Abstract

The structure of the title compound, C₅H₅N₂O₂ ⁺·Cl⁻, is composed of chloride anions and 4-carboxy­pyridazin-1-ium cations. Chloride anions bridge the cations via O—H⋯Cl and N—H⋯Cl hydrogen bonds to form ribbons. The latter, linked by van der Waals forces with lengths in the range 3.254 (2)–3.497 (2) Å, form coplanar layers. Very weak inter­actions operate also between adjacent layers, as indicated by their spacing of 3.339 (1) Å.

Related literature

For the crystal structure of pyridazine-3-carboxylic acid hydro­chloride, see: Gryz et al. (2003 ▶). For a report of mol­ecular layers in the structure of pyrazine-2-carboxylic acid, see: Takusagawa et al. (1974 ▶).

Experimental

Crystal data

• C₅H₅N₂O₂ ⁺·Cl⁻

• M _r = 160.56

• Monoclinic,

• a = 6.8505 (14) Å

• b = 6.5905 (13) Å

• c = 14.561 (3) Å

• β = 97.65 (3)°

• V = 651.6 (2) ų

• Z = 4

• Mo Kα radiation

• μ = 0.52 mm⁻¹

• T = 293 (2) K

• 0.39 × 0.16 × 0.12 mm

Data collection

• Kuma KM-4 four-circle diffractometer

• Absorption correction: analytical (CrysAlis RED; Oxford Diffraction, 2008 ▶) T _min = 0.942, T _max = 0.952

• 2062 measured reflections

• 1917 independent reflections

• 1318 reflections with I > 2σ(I)

• R _int = 0.024

• 3 standard reflections every 200 reflections intensity decay: 1.1%

Refinement

• R[F ² > 2σ(F ²)] = 0.030

• wR(F ²) = 0.104

• S = 1.03

• 1917 reflections

• 99 parameters

• H atoms treated by a mixture of independent and constrained refinement

• Δρ_max = 0.35 e Å⁻³

• Δρ_min = −0.21 e Å⁻³

Data collection: KM-4 Software (Kuma, 1996 ▶); cell refinement: KM-4 Software; data reduction: DATAPROC (Kuma, 2001 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O2—H2⋯Cl1	0.91 (3)	2.05 (3)	2.9464 (14)	169 (2)
N1—H1⋯Cl1i	0.92 (3)	2.15 (3)	3.0373 (15)	160 (2)

Symmetry code: (i) .

supplementary crystallographic information

Comment

The structure of the title compound (C₅H₅N₂O₂)⁺ Cl^-, I, is built from chloride anions and heterocycle cations. Chloride anions bridge the cations via hydrogen bonds O2—H2···Cl1 2.05 (3)Å and N1—H1···Cl1ⁱ 2.15 (3)Å to form ribbons; symmetry code: (i) x+1/2, -y+3/2, z+1/2. The ribbons linked by van der Waals forces with lengths in the range from 3.254 (2) to 3.497 (2)Å make coplanar layers. The shortest distance between pyridazine rings belonging to adjacent layers is 3.339 (1)Å. The pyridazine ring are planar (r.m.s. 0.0060Å) and formes with the carboxylate group (C7/O1/O2) dihedral angle 27.7 (1)°. Bond lengths and bond angles within the cation agree well with those reported in the structure of pyridazine–3–carboxylic acid hydrochloride (Gryz et al., 2003).

Experimental

Single crystals of I were obtained by recrystallization of pyridazine–4–carboxylic acid (ALDRICH) from warm 1M solution of hydrochloric acid. Attempts to recrystallize from water and alcohols yielded specimens unsuitable for collecting X–ray data.

Refinement

All H atoms bonded with C atoms were positioned geometrically and refined in riding model approximation with C—H = 0.93Å and U_iso(H) = 1.2U_eq(C). The H atoms connected with N and O atoms were located in difference Fourier map and refined isotropically.

Figures

Fig. 1.

A molecular structure of I with the atom labelling scheme. The displacement ellipsoids are drawn at 50% probability level. H atoms are presented as a small spheres of arbitrary radius.

Fig. 2.

The structure packing diagram of I.

Crystal data

C5H5N2O2+·Cl–	F000 = 328
Mr = 160.56	Dx = 1.637 Mg m−3
Monoclinic, P21/n	Mo Kα radiation λ = 0.71073 Å
a = 6.8505 (14) Å	Cell parameters from 6 reflections
b = 6.5905 (13) Å	θ = 6–15º
c = 14.561 (3) Å	µ = 0.52 mm−1
β = 97.65 (3)º	T = 293 (2) K
V = 651.6 (2) Å3	Block, colourless
Z = 4	0.39 × 0.16 × 0.12 mm

Data collection

Kuma KM-4 four-circle diffractometer	Rint = 0.024
Radiation source: Fine–focus sealed tube	θmax = 30.1º
Monochromator: Graphite	θmin = 2.8º
T = 293(2) K	h = −9→0
Profile data from ω/2θ scans	k = 0→9
Absorption correction: Analytical(CrysAlis RED; Oxford Diffraction, 2008)	l = −20→20
Tmin = 0.942, Tmax = 0.952	3 standard reflections
2062 measured reflections	every 200 reflections
1917 independent reflections	intensity decay: 1.2%
1318 reflections with I > 2σ(I)

Refinement

Refinement on F2	Secondary atom site location: Difmap
Least-squares matrix: Full	Hydrogen site location: Geom
R[F2 > 2σ(F2)] = 0.030	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.104	w = 1/[σ2(Fo2) + (0.0577P)2 + 0.1527P] where P = (Fo2 + 2Fc2)/3
S = 1.03	(Δ/σ)max = 0.001
1917 reflections	Δρmax = 0.36 e Å−3
99 parameters	Δρmin = −0.21 e Å−3
Primary atom site location: Direct	Extinction correction: None

Special details

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes.

Refinement. Refinement of F^2^ against ALL reflections. The weighted R–factor wR and goodness of fit S are based on F^2^, conventional R–factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > σ(F^2^) is used only for calculating R–factors(gt) etc. and is not relevant to the choice of reflections for refinement. R–factors based on F^2^ 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
Cl1	0.61082 (6)	0.18289 (6)	0.39362 (3)	0.03696 (13)
O1	0.8041 (2)	0.6663 (2)	0.46266 (8)	0.0485 (3)
C3	0.8870 (3)	0.9337 (3)	0.61752 (11)	0.0382 (4)
H3	0.8395	0.9943	0.5613	0.046*
C4	0.8811 (2)	0.7225 (2)	0.62339 (10)	0.0296 (3)
O2	0.7273 (2)	0.4276 (2)	0.56133 (8)	0.0414 (3)
C7	0.7988 (2)	0.6028 (3)	0.53974 (10)	0.0330 (3)
C5	0.9550 (2)	0.6321 (2)	0.70515 (11)	0.0337 (3)
H5	0.9548	0.4918	0.7120	0.040*
N2	0.9559 (2)	1.0516 (2)	0.68707 (10)	0.0414 (3)
C6	1.0306 (3)	0.7589 (3)	0.77771 (11)	0.0376 (4)
H6	1.0841	0.7045	0.8345	0.045*
N1	1.0257 (2)	0.9555 (2)	0.76522 (10)	0.0368 (3)
H1	1.063 (3)	1.042 (4)	0.8143 (17)	0.063 (7)*
H2	0.675 (4)	0.358 (4)	0.5097 (19)	0.069 (8)*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Cl1	0.0472 (2)	0.02641 (19)	0.0353 (2)	0.00189 (16)	−0.00212 (15)	−0.00355 (14)
O1	0.0698 (9)	0.0472 (8)	0.0264 (6)	0.0011 (7)	−0.0010 (5)	0.0038 (5)
C3	0.0507 (10)	0.0319 (8)	0.0309 (7)	0.0058 (7)	0.0017 (7)	0.0058 (6)
C4	0.0313 (7)	0.0310 (7)	0.0259 (6)	0.0027 (6)	0.0021 (5)	0.0015 (5)
O2	0.0567 (8)	0.0354 (6)	0.0303 (6)	−0.0046 (6)	−0.0010 (5)	−0.0028 (5)
C7	0.0371 (8)	0.0336 (8)	0.0267 (7)	0.0064 (6)	−0.0017 (6)	0.0005 (6)
C5	0.0406 (8)	0.0291 (7)	0.0295 (7)	0.0003 (6)	−0.0025 (6)	0.0030 (5)
N2	0.0554 (9)	0.0296 (7)	0.0386 (7)	0.0022 (7)	0.0041 (6)	0.0022 (5)
C6	0.0463 (9)	0.0349 (8)	0.0288 (7)	−0.0010 (7)	−0.0045 (6)	0.0028 (6)
N1	0.0443 (8)	0.0340 (7)	0.0315 (6)	−0.0034 (6)	0.0023 (5)	−0.0034 (5)

Geometric parameters (Å, °)

O1—C7	1.203 (2)	O2—H2	0.91 (3)
C3—N2	1.313 (2)	C5—C6	1.392 (2)
C3—C4	1.395 (2)	C5—H5	0.9300
C3—H3	0.9300	N2—N1	1.334 (2)
C4—C5	1.367 (2)	C6—N1	1.308 (2)
C4—C7	1.497 (2)	C6—H6	0.9300
O2—C7	1.309 (2)	N1—H1	0.92 (3)
N2—C3—C4	123.60 (15)	C4—C5—C6	117.17 (16)
N2—C3—H3	118.2	C4—C5—H5	121.4
C4—C3—H3	118.2	C6—C5—H5	121.4
C5—C4—C3	118.55 (15)	C3—N2—N1	115.32 (14)
C5—C4—C7	122.31 (15)	N1—C6—C5	119.27 (15)
C3—C4—C7	119.12 (14)	N1—C6—H6	120.4
C7—O2—H2	111.4 (17)	C5—C6—H6	120.4
O1—C7—O2	126.14 (16)	C6—N1—N2	126.06 (15)
O1—C7—C4	121.39 (16)	C6—N1—H1	120.2 (16)
O2—C7—C4	112.47 (13)	N2—N1—H1	113.5 (16)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···Cl1	0.91 (3)	2.05 (3)	2.9464 (14)	169 (2)
N1—H1···Cl1i	0.92 (3)	2.15 (3)	3.0373 (15)	160 (2)

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