4-Methyl-3-nitro­pyridin-2-amine

Khan, M.A.; Tahir, M.N.; Ather, A.Q.; Shaheen, M.; Khan, R.A.

doi:10.1107/S1600536809022582

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 65| Part 7| July 2009| Page o1615

doi:10.1107/S1600536809022582

Open

access

4-Methyl-3-nitropyridin-2-amine

Misbahul Ain Khan,^a M. Nawaz Tahir,^b ^* Abdul Qayyum Ather,^c Maryam Shaheen ^a and Rauf Ahmad Khan ^c

^aInstitute of Chemistry, University of the Punjab, Lahore, Pakistan, ^bUniversity of Sargodha, Department of Physics, Sargodha, Pakistan, and ^cApplied Chemistry Research Center, PCSIR Laboratories complex, Lahore 54600, Pakistan
^*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 11 June 2009; accepted 12 June 2009; online 20 June 2009)

In the title compound, C₆H₇N₃O₂, the dihedral angle between the nitro group and the pyridine ring is 15.5 (3)° and an intramolecular N—H⋯O hydrogen bond occurs. In the crystal, inversion dimers linked by two N—H⋯N hydrogen bonds occur, resulting in R₂²(8) rings. The packing is stabilized by aromatic π–π stacking [centroid–centroid distance = 3.5666 (15) Å] and a short N—O⋯π contact is seen.

Related literature

For a related structure, see: Kvick & Noordik (1977 ). For graph-set notation, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₆H₇N₃O₂
M_r = 153.15
Monoclinic, P 2₁ /n
a = 7.3776 (6) Å
b = 12.8673 (11) Å
c = 7.3884 (6) Å
β = 104.364 (4)°
V = 679.45 (10) Å³
Z = 4
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 296 K
0.25 × 0.10 × 0.08 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.985, T_max = 0.992
7483 measured reflections
1677 independent reflections
759 reflections with I > 2σ(I)
R_int = 0.055

Refinement

R[F² > 2σ(F²)] = 0.056
wR(F²) = 0.173
S = 1.00
1677 reflections
107 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.39 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
N2—H2A⋯N1ⁱ	0.88 (3)	2.17 (4)	3.045 (4)	174 (3)
N2—H2B⋯O1	0.85 (3)	2.01 (3)	2.612 (4)	127 (2)
N3—O2⋯Cg1ⁱⁱ	1.20 (1)	3.27 (1)	3.681 (12)	100 (1)
Symmetry codes: (i) -x+1, -y, -z; (ii) -x+2, -y, -z+1. Cg1 is the centroid of the pyridine ring.

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; 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 PLATON (Spek, 2009 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ) and PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809022582/hb5007sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809022582/hb5007Isup2.hkl

checkCIF report

Comment top

Pyridines form a very important class of heterocyclic compounds. In it are included various vitamins, enzymes, pharmaceuticals, dyes, agrochemicals and other products. The title compound (I), (Fig. 1) is nitro substituted 2-Amino-4-methylpyridine.

The crystal structure of (II) 2-Amino-4-methylpyridine (Kvick & Noordik, 1977) has been reported. In (I), the pyridine ring A (C1—C5/N1) is planar with Rms deviation of 0.0135 Å. The amino N-atom and the methyl C-atom deviates from the plane of ring A by -0.0551 (37) Å and -0.044 (4) Å, respectively. The dihedral angle between ring A and nitro group B (O1/N3/O2) is 15.53 (27)°. The title compound consists of dimers due to inversion related intermolecular H-bonds of N–H···N type forming ring motifs R₂²(8) (Bernstein et al., 1995). The interamoleculr H-bond of N–H···O type completes R₁¹(6) ring motif (Fig. 2). The molecules are stabilized due to π–π-interactions with centroid to centroid distance of 3.5666 (15) Å [CgA···CgAⁱ: symmetry code i = 2 - x, -y, -z] and N–O···π interactions (Table 1).

Related literature top

For a related structure, see: Kvick & Noordik (1977). For graph-set notation, see: Bernstein et al. (1995). Cg1 is the centroid of the pyridine ring.

Experimental top

2-Amino-4-picoline (1.1 g, 0.01 mol) was dissolved in 10 ml of concentrated nitric and sulfuric acid (1:1) and cooled to 278 K. The mixture was left overnight and the resultant nitramino product was further treated with 5 ml of conc. sulfuric acid at room temperature for 3 h and poured over 250 g of crushed ice. The precipitates obtained were collected by filtration and subjected to steam distillation. The title compound was obtained as yellow needles of (I) on cooling the distillate to room temperature.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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 PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top

	Fig. 1. View of (I) with displacement ellipsoids drawn at the 50% probability level. H-atoms are shown by small spheres of arbitrary radii. Intermolecular H-bond is shown by dotted lines.
	Fig. 2. The partial packing of (I), which shows that molecules form dimers.

4-Methyl-3-nitropyridin-2-amine top

Crystal data top

C₆H₇N₃O₂	F(000) = 320
M_r = 153.15	D_x = 1.497 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 1677 reflections
a = 7.3776 (6) Å	θ = 3.2–28.3°
b = 12.8673 (11) Å	µ = 0.12 mm⁻¹
c = 7.3884 (6) Å	T = 296 K
β = 104.364 (4)°	Needle, yellow
V = 679.45 (10) Å³	0.25 × 0.10 × 0.08 mm
Z = 4

Data collection top

Bruker Kappa APEXII CCD diffractometer	1677 independent reflections
Radiation source: fine-focus sealed tube	759 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.055
Detector resolution: 7.40 pixels mm^-1	θ_max = 28.3°, θ_min = 3.2°
ω scans	h = −9→9
Absorption correction: multi-scan (SADABS; Bruker, 2005)	k = −17→17
T_min = 0.985, T_max = 0.992	l = −9→9
7483 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)] = 0.056	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.173	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	w = 1/[σ²(F_o²) + (0.0745P)² + 0.0769P] where P = (F_o² + 2F_c²)/3
1677 reflections	(Δ/σ)_max < 0.001
107 parameters	Δρ_max = 0.39 e Å⁻³
0 restraints	Δρ_min = −0.32 e Å⁻³

Crystal data top

C₆H₇N₃O₂	V = 679.45 (10) Å³
M_r = 153.15	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 7.3776 (6) Å	µ = 0.12 mm⁻¹
b = 12.8673 (11) Å	T = 296 K
c = 7.3884 (6) Å	0.25 × 0.10 × 0.08 mm
β = 104.364 (4)°

Data collection top

Bruker Kappa APEXII CCD diffractometer	1677 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	759 reflections with I > 2σ(I)
T_min = 0.985, T_max = 0.992	R_int = 0.055
7483 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.056	0 restraints
wR(F²) = 0.173	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	Δρ_max = 0.39 e Å⁻³
1677 reflections	Δρ_min = −0.32 e Å⁻³
107 parameters

Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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 (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.9915 (3)	−0.20091 (18)	0.2978 (3)	0.0860 (10)
O2	1.2249 (3)	−0.11801 (19)	0.4483 (4)	0.0904 (10)
N1	0.7197 (3)	0.06783 (18)	0.0831 (3)	0.0426 (8)
N2	0.6845 (4)	−0.1039 (2)	0.1310 (3)	0.0529 (9)
N3	1.0759 (3)	−0.11908 (19)	0.3358 (3)	0.0475 (9)
C1	0.8004 (4)	−0.0221 (2)	0.1552 (3)	0.0386 (8)
C2	0.9935 (3)	−0.0238 (2)	0.2507 (3)	0.0378 (9)
C3	1.1041 (3)	0.0656 (2)	0.2608 (3)	0.0405 (9)
C4	1.0135 (4)	0.1542 (2)	0.1803 (4)	0.0480 (10)
C5	0.8246 (4)	0.1511 (2)	0.0979 (4)	0.0472 (10)
C6	1.3108 (4)	0.0719 (3)	0.3480 (4)	0.0555 (10)
H2A	0.570 (5)	−0.089 (2)	0.066 (4)	0.0635*
H2B	0.730 (4)	−0.164 (2)	0.156 (4)	0.0635*
H4	1.07986	0.21582	0.18170	0.0576*
H5	0.76702	0.21275	0.04899	0.0566*
H6A	1.35738	0.13785	0.31888	0.0666*
H6B	1.37365	0.01708	0.29973	0.0666*
H6C	1.33334	0.06475	0.48107	0.0666*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0667 (16)	0.0497 (16)	0.127 (2)	−0.0025 (12)	−0.0035 (14)	0.0240 (14)
O2	0.0609 (15)	0.0759 (19)	0.110 (2)	0.0105 (13)	−0.0247 (14)	0.0200 (14)
N1	0.0373 (12)	0.0424 (14)	0.0475 (13)	0.0041 (11)	0.0096 (10)	−0.0006 (11)
N2	0.0399 (13)	0.0506 (17)	0.0639 (16)	−0.0020 (13)	0.0048 (12)	0.0097 (14)
N3	0.0416 (14)	0.0502 (17)	0.0506 (14)	0.0091 (12)	0.0110 (12)	0.0076 (12)
C1	0.0355 (14)	0.0427 (16)	0.0394 (14)	0.0019 (13)	0.0126 (11)	−0.0016 (12)
C2	0.0356 (15)	0.0404 (16)	0.0378 (14)	0.0070 (12)	0.0101 (11)	0.0004 (12)
C3	0.0361 (14)	0.0500 (18)	0.0354 (14)	0.0038 (13)	0.0090 (11)	−0.0046 (12)
C4	0.0493 (18)	0.0399 (17)	0.0547 (17)	−0.0042 (14)	0.0126 (14)	−0.0032 (14)
C5	0.0495 (18)	0.0421 (17)	0.0492 (16)	0.0105 (14)	0.0110 (13)	−0.0001 (13)
C6	0.0391 (16)	0.066 (2)	0.0589 (18)	−0.0051 (14)	0.0077 (13)	−0.0058 (16)

Geometric parameters (Å, º) top

O1—N3	1.220 (3)	C2—C3	1.402 (4)
O2—N3	1.203 (3)	C3—C4	1.380 (4)
N1—C1	1.349 (3)	C3—C6	1.503 (4)
N1—C5	1.310 (4)	C4—C5	1.376 (4)
N2—C1	1.340 (4)	C4—H4	0.9300
N3—C2	1.442 (3)	C5—H5	0.9300
N2—H2B	0.85 (3)	C6—H6A	0.9600
N2—H2A	0.88 (3)	C6—H6B	0.9600
C1—C2	1.425 (4)	C6—H6C	0.9600

C1—N1—C5	118.4 (2)	C2—C3—C4	116.2 (2)
O1—N3—O2	119.7 (2)	C4—C3—C6	118.2 (3)
O1—N3—C2	119.9 (2)	C3—C4—C5	119.7 (2)
O2—N3—C2	120.4 (2)	N1—C5—C4	125.0 (3)
H2A—N2—H2B	126 (3)	C3—C4—H4	120.00
C1—N2—H2A	113.3 (18)	C5—C4—H4	120.00
C1—N2—H2B	119 (2)	N1—C5—H5	118.00
N1—C1—N2	114.6 (3)	C4—C5—H5	118.00
N1—C1—C2	119.9 (2)	C3—C6—H6A	109.00
N2—C1—C2	125.5 (2)	C3—C6—H6B	109.00
N3—C2—C1	119.4 (2)	C3—C6—H6C	109.00
N3—C2—C3	119.9 (2)	H6A—C6—H6B	109.00
C1—C2—C3	120.8 (2)	H6A—C6—H6C	109.00
C2—C3—C6	125.6 (2)	H6B—C6—H6C	109.00

C5—N1—C1—N2	−178.7 (2)	N2—C1—C2—N3	−2.1 (4)
C5—N1—C1—C2	2.3 (4)	N2—C1—C2—C3	177.2 (2)
C1—N1—C5—C4	0.8 (4)	N3—C2—C3—C4	−178.3 (2)
O1—N3—C2—C1	13.3 (3)	N3—C2—C3—C6	2.8 (4)
O1—N3—C2—C3	−166.0 (2)	C1—C2—C3—C4	2.4 (3)
O2—N3—C2—C1	−164.5 (2)	C1—C2—C3—C6	−176.4 (2)
O2—N3—C2—C3	16.2 (4)	C2—C3—C4—C5	0.5 (4)
N1—C1—C2—N3	176.7 (2)	C6—C3—C4—C5	179.5 (3)
N1—C1—C2—C3	−4.0 (3)	C3—C4—C5—N1	−2.3 (5)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···N1ⁱ	0.88 (3)	2.17 (4)	3.045 (4)	174 (3)
N2—H2B···O1	0.85 (3)	2.01 (3)	2.612 (4)	127 (2)
N3—O2···Cg1ⁱⁱ	1.20 (1)	3.27 (1)	3.681 (12)	100 (1)

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

Experimental details

Crystal data
Chemical formula	C₆H₇N₃O₂
M_r	153.15
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	296
a, b, c (Å)	7.3776 (6), 12.8673 (11), 7.3884 (6)
β (°)	104.364 (4)
V (Å³)	679.45 (10)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.12
Crystal size (mm)	0.25 × 0.10 × 0.08

Data collection
Diffractometer	Bruker Kappa APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.985, 0.992
No. of measured, independent and observed [I > 2σ(I)] reflections	7483, 1677, 759
R_int	0.055
(sin θ/λ)_max (Å⁻¹)	0.667

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.056, 0.173, 1.00
No. of reflections	1677
No. of parameters	107
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.39, −0.32

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···N1ⁱ	0.88 (3)	2.17 (4)	3.045 (4)	174 (3)
N2—H2B···O1	0.85 (3)	2.01 (3)	2.612 (4)	127 (2)
N3—O2···Cg1ⁱⁱ	1.203 (3)	3.2743 (3)	3.681 (12)	100.16 (17)

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

Acknowledgements

The authors acknowledge the Higher Education Commission, Islamabad, Pakistan, and Bana International, Karachi, Pakistan, for funding the purchase of the diffractometer at GCU, Lahore and for technical support, respectively.

References

Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573. CrossRef CAS Web of Science Google Scholar
Bruker (2005). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838. CrossRef CAS IUCr Journals Google Scholar
Kvick, Å. & Noordik, J. (1977). Acta Cryst. B33, 2862–2866. CSD CrossRef CAS IUCr Journals Web of Science Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar