2-Amino-5-nitro­pyridinium hydrogen oxalate

Rajkumar, M.A.; Xavier, S.S.J.; Anbarasu, S.; Devarajan, P.A.; NizamMohideen, M.

doi:10.1107/S160053681400525X

organic compounds

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ISSN: 2056-9890

Volume 70| Part 4| April 2014| Pages o473-o474

doi:10.1107/S160053681400525X

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2-Amino-5-nitropyridinium hydrogen oxalate

M. Ambrose Rajkumar,^a S. Stanly John Xavier,^b S. Anbarasu,^a Prem Anand Devarajan ^a ^* and M. NizamMohideen ^c ^*

^aPhysics Research Centre, Department of Physics, St Xavier's College (Autonomous), Palayamkottai 627 002, Tamil Nadu, India, ^bDepartment of Chemistry, St Xavier's College (Autonomous), Palayamkottai 627 002, Tamil Nadu, India, and ^cDepartment of Physics, The New College (Autonomous), Chennai 600 014, Tamil Nadu, India
^*Correspondence e-mail: devarajanpremanand@gmail.com, mnizam_new@yahoo.in

(Received 6 February 2014; accepted 7 March 2014; online 26 March 2014)

In the cation of the title molecular salt, C₅H₆N₃O₂⁺·C₂HO₄⁻, the dihedral angle between the aromatic ring and the nitro group is 3.5 (3)°; in the anion, the dihedral angle between the CO2 and CO₂H planes is 10.5 (2)°. In the crystal, the anions are linked into [100] chains by O—H⋯O hydrogen bonds. The cations cross-link the chains by way of N—H⋯O hydrogen bonds and the structure is consolidated by C—H⋯O interactions.

CCDC reference: 990527

Related literature

For the crystal structures of related pyridine derivatives, see: Babu et al. (2014 ); Anderson et al. (2005 ); Karle et al. (2003 ). For simple organic–inorganic salts containing strong intermolecular hydrogen bonds, see: Fu et al. (2011 ); Sethuram et al. (2013a ,b ); Shihabuddeen Syed et al. (2013 ); Showrilu et al. (2013 ); Huq et al. (2013 ). For the structure of oxalic acid, see: Derissen & Smith (1974 ). For graph-set analysis, see: Bernstein et al.(1995 ).

Experimental

Crystal data

C₅H₆N₃O₂⁺·C₂HO₄⁻
M_r = 229.16
Triclinic, $[P \overline 1]$
a = 5.5609 (2) Å
b = 9.2012 (4) Å
c = 9.2305 (4) Å
α = 90.245 (2)°
β = 98.500 (2)°
γ = 100.038 (2)°
V = 459.74 (3) Å³
Z = 2
Mo Kα radiation
μ = 0.15 mm⁻¹
T = 293 K
0.35 × 0.30 × 0.30 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2004 ) T_min = 0.950, T_max = 0.957
10142 measured reflections
1615 independent reflections
1417 reflections with I > 2σ(I)
R_int = 0.020

Refinement

R[F² > 2σ(F²)] = 0.039
wR(F²) = 0.110
S = 1.07
1615 reflections
153 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.28 e Å⁻³
Δρ_min = −0.32 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯O5ⁱ	0.93	2.48	3.323 (2)	152
C3—H3⋯O2ⁱⁱ	0.93	2.37	3.296 (2)	178
C5—H5⋯O1ⁱⁱⁱ	0.93	2.42	3.186 (2)	140
C5—H5⋯O4^iv	0.93	2.44	2.970 (2)	116
N1—H1⋯O6^iv	0.86	1.94	2.7697 (18)	160
O4—H4⋯O5^v	0.82	1.64	2.4486 (16)	170
N2—H2A⋯O3^v	0.89 (3)	2.16 (3)	2.959 (2)	149 (2)
N2—H2A⋯O5^v	0.89 (3)	2.36 (3)	3.007 (2)	130 (2)
N2—H2B⋯O3^vi	0.89 (3)	1.99 (3)	2.870 (2)	173 (2)
Symmetry codes: (i) -x+2, -y+1, -z+2; (ii) -x+2, -y, -z+2; (iii) -x+1, -y, -z+1; (iv) -x+1, -y+1, -z+1; (v) x-1, y, z; (vi) -x+1, -y+1, -z+2.

Data collection: APEX2 (Bruker, 2004 ); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ) and Mercury (Macrae et al., 2008 ); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009 ).

Supporting information

CCDC reference: 990527

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053681400525X/jj2183sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681400525X/jj2183Isup2.hkl

Supporting information file. DOI: 10.1107/S160053681400525X/jj2183Isup3.cml

checkCIF report

Comment top

Simple organic–inorganic salts containing strong intermolecular hydrogen bonds have attracted an attention as materials which display ferroelectric-paraelectric phase transitions (Fu et al., 2011; Sethuram, et al., 2013a,b; Huq, et al., 2013; Shihabuddeen Syed, et al., 2013; Showrilu, et al., 2013). As part of our ongoing investigations of pyridine derivatives (Babu et al., 2014), the title compound was synthesized and we report herein on its crystal structure.

In the title salt, (C₅H₆N₃O₂)⁺, (C₂HO₄)^-, the asymmetric unit consists of an independent 2-amino-5-nitropyridinium cation, and oxalic actetate anion, which lie on an inversion symmetry. A proton transfer from the carboxyl group of oxalic acid to atom N1 of 2-amino-5-nitro pyridinine resulted in the formation of a salt. This protonation lead to the widening of the C5-N1-C1 angle of the pyridine ring to 122.79 (14)°, compared to 115.25 (13)° in the unprotonated aminopyridine (Anderson et al., 2005). This type of protonation is observed in various aminopyridine acid complexes (Babu et al., 2014; Karle et al., 2003).

The bond lengths and bond angles of the aminopyridine are comparable to the values reported earlier for aminopyridine (Babu et al., 2014; Anderson et al., 2005). The bond lengths and bond angles of the oxalate are comparable to the values reported for oxalic acid (Derissen & Smith, 1974). The non hydrogen pyridine ring, C1/C2/C3/C4/C5/N1, is planar with a maximum deviation of 0.006 (1)Å from the least squares plane for the C3 atom, with the endocyclic angles covering range of 117.88 (16) - 122.79 (14)°. The hydrogen oxalate anion O3/O4/O5/O6/C6/C7, is less planar with a maximum deviation of -0.131 (1)Å for the O3 and O6 atoms.

The crystal packing is consolidated by intermolecular N—H···O and O—H···O hydrogen bonds and weak C—H···O intermolecular interactions (Table 1 and Fig. 2). In the crystal structure, the 2-Amino-5-nitropyridinium unit is bound to acetate anions by five distinct N—H···O hydrogen bonds. The ion pairs are joined by two N—H···O hydrogen bonds in which the N atom of the 2-amino-5-nitroPyridinium unit acts as a bifurcated donor, thus generating R₁²(5) ring motifs (Bernstein et al., 1995). The hydroxyl group hydrogen atom is also hydrogen-bonded to the carboxylate oxygen atom through strong intermolecular O—H···O hydrogen bonds, with the O···O distance of 2.4486 (16)Å, which is from a chain, C(5), running along the b axis (Bernstein et al., 1995). The structure is further stabilized by weak C—H···O intermolecular inteactions, forming a three-dimensional network.

Related literature top

For the crystal structures of related pyridine derivatives, see: Babu et al. (2014); Anderson et al. (2005); Karle et al. (2003). For simple organic–inorganic salts containing strong intermolecular hydrogen bonds, see: Fu et al. (2011); Sethuram et al. (2013a,b); Shihabuddeen Syed et al. (2013); Showrilu et al. (2013); Huq et al. (2013). For the structure of oxalic acid, see: Derissen & Smith (1974). For graph-set analysis, see: Bernstein et al.(1995).

Experimental top

Crystals of the title compound were obtained by slow evaporation of a 1:1 mol. mixture of 2-amino-5-nitropyridine and oxalic acid in methanol at room temperature.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2008); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Figures top

	Fig. 1. View of the title compound showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 40% probability level. H atoms are presented as a small spheres of arbitrary radius.
	Fig. 2. The crystal packing of the title compound viewed along a axis. N—H···O, O—H···O hydrogen bonds and weak C—H···O intermolecular inteeractions are shown as dashed lines, forming a three-dimensional network. H atoms not involved in hydrogen bonding have been omitted for clarity.

2-Amino-5-nitropyridinium hydrogen oxalate top

Crystal data top

C₅H₆N₃O₂⁺·C₂HO₄⁻	Z = 2
M_r = 229.16	F(000) = 236
Triclinic, P1	D_x = 1.655 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 5.5609 (2) Å	Cell parameters from 2794 reflections
b = 9.2012 (4) Å	θ = 2.4–31.1°
c = 9.2305 (4) Å	µ = 0.15 mm⁻¹
α = 90.245 (2)°	T = 293 K
β = 98.500 (2)°	Block, colourless
γ = 100.038 (2)°	0.35 × 0.30 × 0.30 mm
V = 459.74 (3) Å³

Data collection top

Bruker Kappa APEXII CCD diffractometer	1615 independent reflections
Radiation source: fine-focus sealed tube	1417 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.020
Detector resolution: 0.1000 pixels mm^-1	θ_max = 25.0°, θ_min = 2.2°
ω and ϕ scans	h = −6→6
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	k = −10→10
T_min = 0.950, T_max = 0.957	l = −10→10
10142 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.110	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ²(F_o²) + (0.0559P)² + 0.2329P] where P = (F_o² + 2F_c²)/3
1615 reflections	(Δ/σ)_max < 0.001
153 parameters	Δρ_max = 0.28 e Å⁻³
0 restraints	Δρ_min = −0.32 e Å⁻³

Crystal data top

C₅H₆N₃O₂⁺·C₂HO₄⁻	γ = 100.038 (2)°
M_r = 229.16	V = 459.74 (3) Å³
Triclinic, P1	Z = 2
a = 5.5609 (2) Å	Mo Kα radiation
b = 9.2012 (4) Å	µ = 0.15 mm⁻¹
c = 9.2305 (4) Å	T = 293 K
α = 90.245 (2)°	0.35 × 0.30 × 0.30 mm
β = 98.500 (2)°

Data collection top

Bruker Kappa APEXII CCD diffractometer	1615 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	1417 reflections with I > 2σ(I)
T_min = 0.950, T_max = 0.957	R_int = 0.020
10142 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.039	0 restraints
wR(F²) = 0.110	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	Δρ_max = 0.28 e Å⁻³
1615 reflections	Δρ_min = −0.32 e Å⁻³
153 parameters

Special details top

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

	x	y	z	U_iso*/U_eq
C1	0.3486 (3)	0.30577 (19)	0.87248 (18)	0.0302 (4)
C2	0.5136 (3)	0.2468 (2)	0.97783 (19)	0.0361 (4)
H2	0.5206	0.2695	1.0768	0.043*
C3	0.6606 (3)	0.1580 (2)	0.9356 (2)	0.0380 (4)
H3	0.7711	0.1201	1.0046	0.046*
C4	0.6446 (3)	0.12349 (19)	0.78639 (19)	0.0338 (4)
C5	0.4879 (3)	0.18053 (19)	0.68547 (19)	0.0332 (4)
H5	0.4796	0.1582	0.5863	0.040*
C6	0.8206 (3)	0.61691 (18)	0.66445 (17)	0.0270 (4)
C7	1.0607 (3)	0.64305 (19)	0.59536 (17)	0.0269 (4)
N1	0.3441 (3)	0.26987 (16)	0.72996 (15)	0.0323 (4)
H1	0.2451	0.3057	0.6649	0.039*
N2	0.2009 (3)	0.39211 (19)	0.90933 (19)	0.0408 (4)
N3	0.7996 (3)	0.02858 (19)	0.73614 (19)	0.0450 (4)
O1	0.7803 (3)	−0.0001 (2)	0.60645 (19)	0.0674 (5)
O2	0.9490 (4)	−0.0148 (3)	0.8270 (2)	0.0882 (7)
O3	0.8197 (2)	0.56345 (16)	0.78510 (13)	0.0410 (4)
O4	0.6388 (2)	0.65291 (16)	0.58166 (14)	0.0409 (4)
H4	0.5159	0.6372	0.6226	0.061*
O5	1.2521 (2)	0.62615 (16)	0.68401 (13)	0.0395 (4)
O6	1.0537 (2)	0.67353 (14)	0.46624 (12)	0.0342 (3)
H2A	0.114 (5)	0.439 (3)	0.842 (3)	0.060 (7)*
H2B	0.208 (4)	0.407 (2)	1.005 (3)	0.051 (6)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0316 (9)	0.0336 (9)	0.0242 (8)	0.0042 (7)	0.0024 (7)	0.0058 (7)
C2	0.0424 (10)	0.0428 (10)	0.0217 (8)	0.0085 (8)	−0.0013 (7)	0.0051 (7)
C3	0.0379 (10)	0.0426 (10)	0.0313 (9)	0.0111 (8)	−0.0070 (7)	0.0093 (8)
C4	0.0324 (9)	0.0333 (9)	0.0351 (10)	0.0082 (7)	0.0002 (7)	0.0039 (7)
C5	0.0387 (10)	0.0347 (9)	0.0253 (9)	0.0074 (7)	0.0010 (7)	0.0015 (7)
C6	0.0212 (8)	0.0392 (9)	0.0216 (8)	0.0085 (7)	0.0027 (6)	0.0034 (6)
C7	0.0205 (8)	0.0390 (9)	0.0221 (8)	0.0082 (6)	0.0022 (6)	0.0029 (6)
N1	0.0344 (8)	0.0391 (8)	0.0231 (7)	0.0118 (6)	−0.0027 (6)	0.0064 (6)
N2	0.0464 (10)	0.0537 (10)	0.0275 (9)	0.0224 (8)	0.0064 (7)	0.0078 (7)
N3	0.0458 (10)	0.0423 (9)	0.0481 (11)	0.0169 (8)	−0.0003 (8)	0.0007 (7)
O1	0.0832 (12)	0.0683 (11)	0.0567 (10)	0.0355 (9)	0.0044 (9)	−0.0148 (8)
O2	0.0942 (14)	0.1202 (17)	0.0668 (12)	0.0807 (14)	−0.0069 (10)	0.0069 (11)
O3	0.0313 (7)	0.0720 (9)	0.0249 (7)	0.0190 (6)	0.0090 (5)	0.0143 (6)
O4	0.0193 (6)	0.0712 (9)	0.0359 (7)	0.0150 (6)	0.0074 (5)	0.0221 (6)
O5	0.0192 (6)	0.0751 (10)	0.0257 (6)	0.0139 (6)	0.0014 (5)	0.0102 (6)
O6	0.0257 (6)	0.0560 (8)	0.0234 (6)	0.0122 (5)	0.0054 (5)	0.0099 (5)

Geometric parameters (Å, º) top

C1—N2	1.315 (2)	C6—O3	1.220 (2)
C1—N1	1.351 (2)	C6—O4	1.268 (2)
C1—C2	1.413 (2)	C6—C7	1.545 (2)
C2—C3	1.347 (3)	C7—O6	1.222 (2)
C2—H2	0.9300	C7—O5	1.2759 (19)
C3—C4	1.398 (3)	N1—H1	0.8600
C3—H3	0.9300	N2—H2A	0.89 (3)
C4—C5	1.352 (2)	N2—H2B	0.89 (3)
C4—N3	1.448 (2)	N3—O1	1.210 (2)
C5—N1	1.344 (2)	N3—O2	1.211 (2)
C5—H5	0.9300	O4—H4	0.8200

N2—C1—N1	119.96 (16)	O3—C6—C7	120.04 (14)
N2—C1—C2	122.16 (16)	O4—C6—C7	112.84 (13)
N1—C1—C2	117.88 (16)	O6—C7—O5	126.27 (14)
C3—C2—C1	120.31 (16)	O6—C7—C6	120.06 (14)
C3—C2—H2	119.8	O5—C7—C6	113.64 (13)
C1—C2—H2	119.8	C5—N1—C1	122.79 (14)
C2—C3—C4	118.97 (16)	C5—N1—H1	118.6
C2—C3—H3	120.5	C1—N1—H1	118.6
C4—C3—H3	120.5	C1—N2—H2A	121.5 (16)
C5—C4—C3	120.75 (17)	C1—N2—H2B	115.1 (15)
C5—C4—N3	118.45 (16)	H2A—N2—H2B	123 (2)
C3—C4—N3	120.79 (16)	O1—N3—O2	123.01 (19)
N1—C5—C4	119.29 (16)	O1—N3—C4	119.28 (16)
N1—C5—H5	120.4	O2—N3—C4	117.68 (17)
C4—C5—H5	120.4	C6—O4—H4	109.5
O3—C6—O4	127.10 (15)

N2—C1—C2—C3	179.55 (17)	O3—C6—C7—O5	−10.4 (2)
N1—C1—C2—C3	0.1 (3)	O4—C6—C7—O5	171.21 (16)
C1—C2—C3—C4	−0.9 (3)	C4—C5—N1—C1	−0.1 (3)
C2—C3—C4—C5	1.3 (3)	N2—C1—N1—C5	−179.04 (16)
C2—C3—C4—N3	179.89 (17)	C2—C1—N1—C5	0.4 (3)
C3—C4—C5—N1	−0.8 (3)	C5—C4—N3—O1	−1.9 (3)
N3—C4—C5—N1	−179.43 (16)	C3—C4—N3—O1	179.50 (18)
O3—C6—C7—O6	168.06 (17)	C5—C4—N3—O2	175.9 (2)
O4—C6—C7—O6	−10.3 (2)	C3—C4—N3—O2	−2.7 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O5ⁱ	0.93	2.48	3.323 (2)	152
C3—H3···O2ⁱⁱ	0.93	2.37	3.296 (2)	178
C5—H5···O1ⁱⁱⁱ	0.93	2.42	3.186 (2)	140
C5—H5···O4^iv	0.93	2.44	2.970 (2)	116
N1—H1···O4^iv	0.86	2.47	2.9770 (18)	119
N1—H1···O6^iv	0.86	1.94	2.7697 (18)	160
O4—H4···O5^v	0.82	1.64	2.4486 (16)	170
N2—H2A···O3^v	0.89 (3)	2.16 (3)	2.959 (2)	149 (2)
N2—H2A···O5^v	0.89 (3)	2.36 (3)	3.007 (2)	130 (2)
N2—H2B···O3^vi	0.89 (3)	1.99 (3)	2.870 (2)	173 (2)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O5ⁱ	0.93	2.48	3.323 (2)	151.6
C3—H3···O2ⁱⁱ	0.93	2.37	3.296 (2)	177.5
C5—H5···O1ⁱⁱⁱ	0.93	2.42	3.186 (2)	139.7
C5—H5···O4^iv	0.93	2.44	2.970 (2)	115.8
N1—H1···O6^iv	0.86	1.94	2.7697 (18)	160.3
O4—H4···O5^v	0.82	1.64	2.4486 (16)	170.0
N2—H2A···O3^v	0.89 (3)	2.16 (3)	2.959 (2)	149 (2)
N2—H2A···O5^v	0.89 (3)	2.36 (3)	3.007 (2)	130 (2)
N2—H2B···O3^vi	0.89 (3)	1.99 (3)	2.870 (2)	173 (2)

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

Acknowledgements

MAR, DPA and SJX would like to thank the Board of Research in Nuclear Sciences, Department of Atomic Energy (BRNS-DAE) (file No. 2012/34/63/BRNS/2865; dated 01/03/2013), for funding this major research project.

References

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