2-Amino-3-nitro­pyridinium hydrogen oxalate

Abstract

In the non-centrosymetric title compound, C₅H₆N₃O₂ ⁺·C₂HO₄ ⁻, the hydrogen oxalate anions form corrugated chains parallel to the c axis, linked by O—H⋯O hydrogen bonds. The 2-amino-3-nitro­pyridinium cations are anchored between theses chains by N—H⋯O and C—H⋯O hydrogen bonds and van der Waals and electrostatic inter­actions, creating a three-dimensional network.

Related literature

For related structures, see: Akriche & Rzaigui (2000 ▶, 2009 ▶); Le Fur et al. (1998 ▶); Nicoud et al. (1997 ▶); For a discussion of hydrogen bonding, see: Desiraju (1989 ▶, 1995 ▶).

Experimental

Crystal data

• C₅H₆N₃O₂ ⁺·C₂HO₄ ⁻

• M _r = 229.16

• Orthorhombic,

• a = 15.268 (4) Å

• b = 6.921 (3) Å

• c = 8.807 (2) Å

• V = 930.6 (5) ų

• Z = 4

• Mo Kα radiation

• μ = 0.15 mm⁻¹

• T = 293 K

• 0.33 × 0.25 × 0.21 mm

Data collection

• Enraf–Nonius Turbo CAD-4 diffractometer

• Absorption correction: none

• 2228 measured reflections

• 1190 independent reflections

• 1003 reflections with I > 2σ(I)

• R _int = 0.020

• 2 standard reflections frequency: 120 min intensity decay: 1%

Refinement

• R[F ² > 2σ(F ²)] = 0.034

• wR(F ²) = 0.088

• S = 1.06

• 1190 reflections

• 147 parameters

• 1 restraint

• H-atom parameters constrained

• Δρ_max = 0.33 e Å⁻³

• Δρ_min = −0.20 e Å⁻³

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994 ▶); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1996 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 (Farrugia, 1997 ▶) and DIAMOND (Brandenburg & Putz, 2005 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

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
O3—H3⋯O2i	0.82	1.82	2.632 (2)	171
N1—H1⋯O2	0.86	1.85	2.706 (3)	175
N2—H2A⋯O1	0.86	1.99	2.837 (3)	170
N2—H2B⋯O5	0.86	2.09	2.673 (3)	124
N2—H2B⋯O4ii	0.86	2.51	3.188 (3)	136
C3—H3A⋯O5iii	0.93	2.44	3.178 (3)	136
C4—H4⋯O1iv	0.93	2.33	3.258 (3)	174
C5—H5⋯O6v	0.93	2.57	3.262 (3)	132

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) ; (v) .

supplementary crystallographic information

Comment

The search for new molecular materials for the non-linear optics lies at the basis of our ongoing study of 2-amino-3-nitropyridinium salts. Our strategy is aimed at the production of very cohesive non-centrosymmetric packing of chromophores. We have previously reported two centrosymetric structures of 2-amino-3-nitropyridinium (Akriche & Rzaigui, 2000; Akriche & Rzaigui, 2009). We report here a new non-centrosymmetric structure, 2-amino-3-nitropyridinium hydrogenoxalate.

The asymmetric unit of the title compound consists of one (HC₂O₄)^- anion and one (2-NH₂-3-NO₂C₅H₃NH)⁺ cation (Fig. 1). In the hydrogenoxalate (HC₂O₄)^-, the H atom is located at O3 as is also indicated by elongation of the corresponding C—O distance [O3—C7 is 1.314 (3) Å]. The bond length of C6—C7 is relatively long [1.545 (3) Å] as expected for an oxalate anion. In the 2-amino-3-nitropyridinium cation, nitro and amino groups are ortho to one another, which explains the presence of the intra-cation contact N2—H2B···O5 (Le Fur et al., 1998; Nicoud et al.,1997).

The structure projection in Fig. 2 shows that the oxalate ions are organized in corrugated chains extending along the c axis. The cations are located between these chains and manifest multiple H-bonds. In fact, in this structure there are three categories of H-bond (Table 1), O—H···O, N—H···O and C—H···O. Within each oxalate chain, the (HC₂O₄)^- groups are interconnected by strong O—H···O hydrogen bonds. These chains are themselves interconnected by N—H···O interactions originating from the NH⁺ and NH₂ groups of the cations. It is worth noticing the presence of long C—H···O contacts (Desiraju, 1989; Desiraju, 1995) occurring between cations and between cations and anions. The density of this H-bond scheme constitutes probably the main factor responsible for the formation of a non-centrosymetric material.

Experimental

An aqueous solution containing 0.004 mol of H₂C₂O₄ in 10 ml of water, was added to 0.004 mol of 2-amino-3-nitropyridine in 20 ml of pure acetic acid. The obtained yellow solution was stirred at 333 K for 10 min and then left to stand at room temperature. Yellow single crystals of the title compound were obtained after some days.

Figures

Fig. 1.

View of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen bonds are represented as dashed lines.

Fig. 2.

A perspective view of the packing of the title compound. Hydrogen bonds are represented as dashed lines.

Crystal data

C5H6N3O2+·C2HO4−	Dx = 1.636 Mg m−3
Mr = 229.16	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pna21	Cell parameters from 25 reflections
a = 15.268 (4) Å	θ = 9–11°
b = 6.921 (3) Å	µ = 0.15 mm−1
c = 8.807 (2) Å	T = 293 K
V = 930.6 (5) Å3	Rectangular prism, yellow
Z = 4	0.33 × 0.25 × 0.21 mm
F(000) = 472

Data collection

Enraf–Nonius Turbo CAD-4 diffractometer	Rint = 0.020
Radiation source: Enraf–Nonius FR590	θmax = 28.0°, θmin = 2.7°
graphite	h = −20→0
Nonprofiled ω scans	k = −7→9
2228 measured reflections	l = −11→0
1190 independent reflections	2 standard reflections every 120 min
1003 reflections with I > 2σ(I)	intensity decay: 1%

Refinement

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.034	H-atom parameters constrained
wR(F2) = 0.088	w = 1/[σ2(Fo2) + (0.0559P)2 + 0.0295P] where P = (Fo2 + 2Fc2)/3
S = 1.06	(Δ/σ)max = 0.001
1190 reflections	Δρmax = 0.33 e Å−3
147 parameters	Δρmin = −0.20 e Å−3
1 restraint	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.053 (6)

Special details

Geometry. H atoms were treated as riding, with C—H = 0.93 A °, N—H = 0.86 A ° and O—H = 0.82 A °, and with Uiso(H) = 1.2Ueq(C,N) and 1.5Ueq(O). 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	0.18864 (12)	0.6389 (3)	0.4311 (2)	0.0512 (5)
O2	0.10055 (11)	0.5552 (3)	0.2423 (2)	0.0408 (4)
O3	0.05130 (11)	0.5172 (3)	0.6129 (2)	0.0391 (4)
H3	0.0051	0.5043	0.6593	0.059*
O4	−0.03139 (11)	0.6833 (3)	0.4481 (2)	0.0494 (5)
O5	0.49613 (12)	0.5813 (3)	0.1226 (3)	0.0532 (5)
O6	0.52023 (11)	0.6750 (3)	−0.1071 (3)	0.0545 (5)
N1	0.23161 (12)	0.5903 (3)	0.0374 (3)	0.0375 (5)
H1	0.1920	0.5818	0.1065	0.045*
N2	0.33259 (15)	0.6060 (3)	0.2291 (3)	0.0462 (6)
H2A	0.2900	0.6012	0.2930	0.055*
H2B	0.3857	0.6133	0.2612	0.055*
N3	0.47122 (12)	0.6244 (3)	−0.0050 (3)	0.0367 (5)
C1	0.31649 (14)	0.6020 (3)	0.0827 (3)	0.0321 (5)
C2	0.37793 (14)	0.6148 (3)	−0.0380 (3)	0.0318 (5)
C3	0.35201 (16)	0.6188 (4)	−0.1871 (3)	0.0363 (5)
H3A	0.3936	0.6300	−0.2638	0.044*
C4	0.26384 (17)	0.6061 (4)	−0.2236 (3)	0.0437 (6)
H4	0.2452	0.6078	−0.3241	0.052*
C5	0.20572 (16)	0.5911 (4)	−0.1078 (3)	0.0421 (6)
H5	0.1463	0.5811	−0.1298	0.050*
C6	0.11677 (14)	0.5994 (3)	0.3773 (3)	0.0303 (5)
C7	0.03636 (14)	0.6065 (3)	0.4838 (3)	0.0302 (5)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
O1	0.0315 (8)	0.0930 (14)	0.0292 (9)	−0.0146 (10)	−0.0004 (7)	−0.0040 (10)
O2	0.0286 (7)	0.0684 (11)	0.0254 (8)	−0.0040 (8)	0.0007 (7)	−0.0037 (9)
O3	0.0300 (8)	0.0618 (12)	0.0256 (7)	0.0005 (8)	0.0063 (7)	0.0065 (8)
O4	0.0346 (9)	0.0660 (12)	0.0475 (11)	0.0110 (8)	0.0040 (8)	0.0115 (10)
O5	0.0342 (9)	0.0727 (13)	0.0528 (12)	0.0094 (9)	−0.0082 (9)	0.0076 (11)
O6	0.0330 (9)	0.0779 (13)	0.0526 (12)	−0.0118 (9)	0.0125 (8)	−0.0050 (11)
N1	0.0243 (9)	0.0522 (14)	0.0361 (12)	−0.0015 (8)	0.0039 (8)	−0.0004 (9)
N2	0.0317 (10)	0.0773 (18)	0.0296 (11)	−0.0022 (10)	0.0002 (8)	0.0046 (11)
N3	0.0259 (9)	0.0401 (10)	0.0440 (12)	0.0007 (8)	0.0035 (9)	−0.0039 (9)
C1	0.0271 (10)	0.0372 (12)	0.0319 (12)	−0.0008 (9)	0.0024 (9)	0.0020 (9)
C2	0.0252 (10)	0.0356 (11)	0.0347 (12)	0.0013 (8)	0.0024 (9)	−0.0014 (10)
C3	0.0352 (12)	0.0427 (14)	0.0311 (12)	0.0002 (10)	0.0057 (10)	−0.0004 (10)
C4	0.0407 (13)	0.0592 (17)	0.0311 (13)	0.0026 (11)	−0.0038 (10)	−0.0018 (11)
C5	0.0271 (10)	0.0585 (16)	0.0406 (15)	0.0020 (10)	−0.0049 (10)	−0.0044 (12)
C6	0.0279 (10)	0.0391 (11)	0.0240 (10)	−0.0029 (9)	0.0015 (9)	0.0033 (9)
C7	0.0263 (10)	0.0382 (11)	0.0261 (11)	−0.0040 (8)	−0.0003 (8)	−0.0026 (9)

Geometric parameters (Å, °)

O1—C6	1.226 (3)	N2—H2A	0.8600
O2—C6	1.252 (3)	N2—H2B	0.8600
O3—C7	1.314 (3)	N3—C2	1.455 (3)
O3—H3	0.8200	C1—C2	1.420 (3)
O4—C7	1.205 (3)	C2—C3	1.372 (3)
O5—N3	1.223 (3)	C3—C4	1.387 (3)
O6—N3	1.221 (3)	C3—H3A	0.9300
N1—C5	1.338 (4)	C4—C5	1.356 (4)
N1—C1	1.358 (3)	C4—H4	0.9300
N1—H1	0.8600	C5—H5	0.9300
N2—C1	1.313 (3)	C6—C7	1.545 (3)
C7—O3—H3	109.5	C2—C3—C4	120.0 (2)
C5—N1—C1	124.2 (2)	C2—C3—H3A	120.0
C5—N1—H1	117.9	C4—C3—H3A	120.0
C1—N1—H1	117.9	C5—C4—C3	117.8 (2)
C1—N2—H2A	120.0	C5—C4—H4	121.1
C1—N2—H2B	120.0	C3—C4—H4	121.1
H2A—N2—H2B	120.0	N1—C5—C4	121.7 (2)
O6—N3—O5	123.8 (2)	N1—C5—H5	119.1
O6—N3—C2	117.8 (2)	C4—C5—H5	119.1
O5—N3—C2	118.5 (2)	O1—C6—O2	126.8 (2)
N2—C1—N1	117.9 (2)	O1—C6—C7	118.0 (2)
N2—C1—C2	127.6 (2)	O2—C6—C7	115.25 (19)
N1—C1—C2	114.5 (2)	O4—C7—O3	125.6 (2)
C3—C2—C1	121.8 (2)	O4—C7—C6	122.5 (2)
C3—C2—N3	118.2 (2)	O3—C7—C6	111.85 (19)
C1—C2—N3	120.0 (2)
C5—N1—C1—N2	177.8 (3)	C1—C2—C3—C4	−1.3 (4)
C5—N1—C1—C2	−0.2 (4)	N3—C2—C3—C4	178.7 (2)
N2—C1—C2—C3	−176.6 (3)	C2—C3—C4—C5	0.4 (4)
N1—C1—C2—C3	1.2 (3)	C1—N1—C5—C4	−0.7 (5)
N2—C1—C2—N3	3.3 (4)	C3—C4—C5—N1	0.6 (4)
N1—C1—C2—N3	−178.8 (2)	O1—C6—C7—O4	134.2 (3)
O6—N3—C2—C3	14.8 (3)	O2—C6—C7—O4	−45.0 (3)
O5—N3—C2—C3	−165.1 (2)	O1—C6—C7—O3	−46.9 (3)
O6—N3—C2—C1	−165.2 (2)	O2—C6—C7—O3	133.9 (2)
O5—N3—C2—C1	15.0 (3)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O2i	0.82	1.82	2.632 (2)	171
N1—H1···O2	0.86	1.85	2.706 (3)	175
N2—H2A···O1	0.86	1.99	2.837 (3)	170
N2—H2B···O5	0.86	2.09	2.673 (3)	124
N2—H2B···O4ii	0.86	2.51	3.188 (3)	136
C3—H3A···O5iii	0.93	2.44	3.178 (3)	136
C4—H4···O1iv	0.93	2.33	3.258 (3)	174
C5—H5···O6v	0.93	2.57	3.262 (3)	132

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