2,6-Dichloro-3-nitro­pyridine

Fun, H.-K.; Arshad, S.; Chandrakantha, B.; Isloor, A.M.; Shetty, P.

doi:10.1107/S1600536811023683

organic compounds

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ISSN: 2056-9890

Volume 67| Part 7| July 2011| Page o1785

doi:10.1107/S1600536811023683

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2,6-Dichloro-3-nitropyridine

Hoong-Kun Fun,^a ^*‡ Suhana Arshad,^a B. Chandrakantha,^b Arun M. Isloor ^c and Prakash Shetty ^d

^aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, ^bDepartment of Chemistry, Manipal Institute of Technology, Manipal 576 104, India, ^cDepartment of Chemistry, National Institute of Technology-Karnataka, Surathkal, Mangalore 575 025, India, and ^dDepartment of Printing, Manipal Institute of Technology, Manipal 576 104, India
^*Correspondence e-mail: hkfun@usm.my

(Received 15 June 2011; accepted 17 June 2011; online 25 June 2011)

The asymmetric unit of the title compound, C₅H₂Cl₂N₂O₂, consists of two crystallographically independent molecules. The pyridine ring in each molecule is essentially planar, with maximum deviations of 0.004 (4) and 0.007 (4) Å. Short Cl⋯O [3.09 (3) and 3.13 (4) Å] and Cl⋯Cl [3.38 (12) Å] contacts were observed. No significant intermolecular interactions were observed in the crystal packing.

Related literature

For the role of the nitropyridine nucleus in the development of medicinal agents and in the field of agrochemicals, see: Davis et al. (1996 ). For the properties and use of pyridine derivatives, see: Vacher et al. (1998 ); Olah et al. (1980 ); Bare et al. (1989 ). For standard bond lengths, see: Allen et al. (1987 ). For the melting point, see: Johnson et al. (1967 ).

Experimental

Crystal data

C₅H₂Cl₂N₂O₂
M_r = 192.99
Monoclinic, P 2₁ /c
a = 7.9021 (8) Å
b = 19.166 (2) Å
c = 11.0987 (9) Å
β = 122.072 (5)°
V = 1424.4 (2) Å³
Z = 8
Mo Kα radiation
μ = 0.85 mm⁻¹
T = 296 K
0.40 × 0.27 × 0.24 mm

Data collection

Bruker SMART APEXII DUO CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.727, T_max = 0.821
16845 measured reflections
4817 independent reflections
2323 reflections with I > 2σ(I)
R_int = 0.060

Refinement

R[F² > 2σ(F²)] = 0.067
wR(F²) = 0.180
S = 1.08
4817 reflections
199 parameters
H-atom parameters constrained
Δρ_max = 0.55 e Å⁻³
Δρ_min = −0.42 e Å⁻³

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811023683/ng5183sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811023683/ng5183Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811023683/ng5183Isup3.cml

checkCIF report

Comment top

Nitropyridine nucleus played a pivotal role in the development of different medicinal agents and in the field of agrochemicals (Davis et al., 1996). It is seen from the current literature that pyridine derivatives have been developed and used as insecticidal agents (Vacher et al., 1998). Nitrated pyridines and their derivatives are important intermediates in synthesis of heterocyclic compounds in dyes and pharmaceutical products (Olah et al., 1980). Fused heterocycles containing nitropyridine systems have been associated with several biological and medicinal activities including antiolytic (Olah et al., 1980), antiviral and anti-inflammatory (Bare et al., 1989) profiles.

The asymmetric unit of the tittle compound (Fig. 1), consists of two crystallographically independent molecules A and B. The pyridine rings (N1/C1–C5) for molecules A and B are essentially planar with maximum deviations of 0.004 (4) Å at atom C1A and 0.007 (4) Å at atom C3B, respectively. The bond lengths (Allen et al., 1987) and angles are within normal ranges. In addition, short Cl···O [Cl1A···O2A (1 - x, -1/2 + y, 1/2 - z) = 3.093 (3) Å and Cl2A···O2A (1 - x, 2 - y, -z) = 3.132 (4) Å] and Cl···Cl [Cl2A···Cl2A (1 - x, 2 - y, -z) = 3.3839 (12) Å] contacts were observed.

The crystal packing is shown in Fig. 2. No significant intermolecular interactions were observed in the crystal packing.

Related literature top

For the role of the nitropyridine nucleus in the development of medicinal agents and in the field of agrochemicals, see: Davis et al. (1996). For the use of pyridine derivatives as insecticidal agents, see: Vacher et al. (1998). Nitrated pyridines and their derivatives are important intermediates in synthesis of heterocyclic compounds in dyes and pharmaceutical products, see: Olah et al. (1980). Fused heterocycles containing nitropyridine systems have been associated with several biological and medicinal activities including antiolytic (Olah et al., 1980), antiviral and anti-inflammatory (Bare et al., 1989) profiles. For standard of bond lengths, see: Allen et al. (1987). For the melting point, see: Johnson et al. (1967).

Experimental top

2,6-Dichloropyridine (5 g, 0.033 mol) was added lotwise to mixture of concentrated H₂SO₄ (25 ml) and fuming nitric acid (10 ml) at 0 °C. After the addition, the reaction mixture was heated to 65 °C for 2 h. After completion of the reaction, the reaction mixture was cooled to room temperature and quenched with ice water. The solid that separated out was filtered and dried under vacuum. The crude product was purified by column chromatography using silica gel 60–120 mesh size and petroleum ether: ethyl acetate as eluent to afford title compound as a pale yellow solid. Yield: 3.0 g, 46.0%. M.p.: 333–338 K (Johnson et al., 1967).

Computing details top

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 top

	Fig. 1. The molecular structure of the title compound, showing the two independent molecules with atom labels and 30% probability displacement ellipsoids.
	Fig. 2. The crystal packing of the title compound.

2,6-Dichloro-3-nitropyridine top

Crystal data top

C₅H₂Cl₂N₂O₂	F(000) = 768
M_r = 192.99	D_x = 1.800 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3419 reflections
a = 7.9021 (8) Å	θ = 2.4–31.7°
b = 19.166 (2) Å	µ = 0.85 mm⁻¹
c = 11.0987 (9) Å	T = 296 K
β = 122.072 (5)°	Block, yellow
V = 1424.4 (2) Å³	0.40 × 0.27 × 0.24 mm
Z = 8

Data collection top

Bruker SMART APEXII DUO CCD area-detector diffractometer	4817 independent reflections
Radiation source: fine-focus sealed tube	2323 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.060
ϕ and ω scans	θ_max = 31.8°, θ_min = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −11→11
T_min = 0.727, T_max = 0.821	k = −28→28
16845 measured reflections	l = −16→16

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)] = 0.067	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.180	H-atom parameters constrained
S = 1.08	w = 1/[σ²(F_o²) + (0.0527P)² + 1.2999P] where P = (F_o² + 2F_c²)/3
4817 reflections	(Δ/σ)_max = 0.001
199 parameters	Δρ_max = 0.55 e Å⁻³
0 restraints	Δρ_min = −0.42 e Å⁻³

Crystal data top

C₅H₂Cl₂N₂O₂	V = 1424.4 (2) Å³
M_r = 192.99	Z = 8
Monoclinic, P2₁/c	Mo Kα radiation
a = 7.9021 (8) Å	µ = 0.85 mm⁻¹
b = 19.166 (2) Å	T = 296 K
c = 11.0987 (9) Å	0.40 × 0.27 × 0.24 mm
β = 122.072 (5)°

Data collection top

Bruker SMART APEXII DUO CCD area-detector diffractometer	4817 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	2323 reflections with I > 2σ(I)
T_min = 0.727, T_max = 0.821	R_int = 0.060
16845 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.067	0 restraints
wR(F²) = 0.180	H-atom parameters constrained
S = 1.08	Δρ_max = 0.55 e Å⁻³
4817 reflections	Δρ_min = −0.42 e Å⁻³
199 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
Cl1A	0.51344 (18)	0.68002 (5)	0.26085 (12)	0.0667 (3)
Cl2A	0.49627 (16)	0.91466 (4)	0.03753 (9)	0.0540 (3)
O1A	0.6135 (4)	1.00995 (14)	0.4256 (3)	0.0656 (8)
O2A	0.4472 (5)	1.01996 (13)	0.1975 (3)	0.0641 (8)
N1A	0.5042 (4)	0.80475 (13)	0.1709 (3)	0.0411 (6)
N2A	0.5284 (4)	0.98557 (14)	0.3053 (3)	0.0433 (6)
C1A	0.5404 (5)	0.87035 (18)	0.4058 (3)	0.0445 (8)
H1A	0.5538	0.8926	0.4848	0.053*
C2A	0.5356 (5)	0.79924 (18)	0.3979 (4)	0.0463 (8)
H2A	0.5436	0.7720	0.4701	0.056*
C3A	0.5182 (5)	0.76941 (15)	0.2786 (3)	0.0397 (7)
C4A	0.5072 (5)	0.87406 (15)	0.1788 (3)	0.0359 (7)
C5A	0.5251 (5)	0.90936 (15)	0.2945 (3)	0.0351 (7)
Cl1B	1.01800 (19)	0.67408 (5)	0.25606 (12)	0.0673 (3)
Cl2B	0.98563 (15)	0.91167 (5)	0.03234 (9)	0.0532 (3)
O1B	0.9156 (5)	1.00415 (15)	0.3366 (3)	0.0731 (9)
O2B	1.1216 (5)	1.01192 (14)	0.2658 (3)	0.0663 (8)
N1B	1.0071 (4)	0.79906 (13)	0.1667 (3)	0.0403 (6)
N2B	1.0196 (5)	0.97918 (15)	0.2975 (3)	0.0470 (7)
C1B	1.0342 (5)	0.86410 (18)	0.4000 (3)	0.0450 (8)
H1B	1.0422	0.8863	0.4773	0.054*
C2B	1.0342 (5)	0.79259 (19)	0.3928 (4)	0.0481 (8)
H2B	1.0421	0.7650	0.4646	0.058*
C3B	1.0218 (5)	0.76313 (16)	0.2741 (3)	0.0427 (8)
C4B	1.0086 (5)	0.86795 (16)	0.1754 (3)	0.0356 (7)
C5B	1.0219 (5)	0.90270 (16)	0.2895 (3)	0.0376 (7)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1A	0.0972 (8)	0.0347 (4)	0.0768 (7)	0.0060 (5)	0.0521 (7)	0.0129 (4)
Cl2A	0.0868 (7)	0.0430 (4)	0.0416 (5)	−0.0036 (4)	0.0405 (5)	0.0053 (3)
O1A	0.085 (2)	0.0609 (17)	0.0551 (16)	−0.0130 (15)	0.0404 (16)	−0.0206 (13)
O2A	0.093 (2)	0.0406 (13)	0.0633 (17)	0.0096 (13)	0.0444 (17)	0.0094 (12)
N1A	0.0520 (18)	0.0343 (12)	0.0418 (15)	0.0003 (12)	0.0281 (14)	0.0016 (11)
N2A	0.0494 (17)	0.0377 (13)	0.0509 (17)	−0.0023 (12)	0.0321 (15)	−0.0046 (12)
C1A	0.049 (2)	0.056 (2)	0.0346 (17)	0.0028 (16)	0.0257 (17)	0.0035 (14)
C2A	0.050 (2)	0.055 (2)	0.0391 (18)	0.0067 (16)	0.0274 (17)	0.0137 (15)
C3A	0.0457 (19)	0.0331 (14)	0.0429 (18)	0.0047 (13)	0.0252 (17)	0.0086 (13)
C4A	0.0435 (19)	0.0332 (14)	0.0329 (16)	0.0010 (13)	0.0215 (15)	0.0025 (11)
C5A	0.0392 (18)	0.0337 (14)	0.0353 (16)	0.0015 (13)	0.0218 (14)	0.0012 (12)
Cl1B	0.0970 (9)	0.0390 (5)	0.0691 (7)	0.0050 (5)	0.0463 (6)	0.0105 (4)
Cl2B	0.0762 (7)	0.0501 (5)	0.0381 (4)	−0.0015 (4)	0.0335 (5)	0.0079 (3)
O1B	0.084 (2)	0.0648 (18)	0.093 (2)	0.0032 (15)	0.062 (2)	−0.0159 (16)
O2B	0.093 (2)	0.0517 (15)	0.0721 (18)	−0.0135 (15)	0.0556 (18)	−0.0038 (13)
N1B	0.0452 (16)	0.0392 (14)	0.0387 (15)	0.0028 (12)	0.0238 (13)	0.0050 (11)
N2B	0.0530 (18)	0.0447 (15)	0.0421 (16)	−0.0030 (14)	0.0244 (15)	−0.0050 (12)
C1B	0.051 (2)	0.0542 (19)	0.0355 (17)	−0.0033 (16)	0.0268 (17)	−0.0007 (14)
C2B	0.052 (2)	0.059 (2)	0.0369 (18)	−0.0006 (17)	0.0255 (17)	0.0104 (15)
C3B	0.046 (2)	0.0391 (16)	0.0417 (19)	0.0036 (14)	0.0224 (17)	0.0085 (14)
C4B	0.0360 (18)	0.0426 (16)	0.0296 (15)	0.0014 (13)	0.0183 (14)	0.0045 (12)
C5B	0.0385 (18)	0.0420 (16)	0.0358 (16)	−0.0011 (14)	0.0221 (15)	0.0013 (13)

Geometric parameters (Å, º) top

Cl1A—C3A	1.723 (3)	Cl1B—C3B	1.717 (3)
Cl2A—C4A	1.711 (3)	Cl2B—C4B	1.717 (3)
O1A—N2A	1.224 (3)	O1B—N2B	1.214 (4)
O2A—N2A	1.209 (4)	O2B—N2B	1.211 (4)
N1A—C4A	1.331 (4)	N1B—C4B	1.323 (4)
N1A—C3A	1.326 (4)	N1B—C3B	1.327 (4)
N2A—C5A	1.465 (4)	N2B—C5B	1.469 (4)
C1A—C2A	1.365 (5)	C1B—C2B	1.373 (5)
C1A—C5A	1.393 (4)	C1B—C5B	1.391 (4)
C1A—H1A	0.9300	C1B—H1B	0.9300
C2A—C3A	1.381 (5)	C2B—C3B	1.389 (5)
C2A—H2A	0.9300	C2B—H2B	0.9300
C4A—C5A	1.391 (4)	C4B—C5B	1.385 (4)

C4A—N1A—C3A	117.4 (3)	C4B—N1B—C3B	117.3 (3)
O2A—N2A—O1A	124.5 (3)	O2B—N2B—O1B	125.5 (3)
O2A—N2A—C5A	119.0 (3)	O2B—N2B—C5B	117.9 (3)
O1A—N2A—C5A	116.5 (3)	O1B—N2B—C5B	116.6 (3)
C2A—C1A—C5A	119.5 (3)	C2B—C1B—C5B	118.8 (3)
C2A—C1A—H1A	120.2	C2B—C1B—H1B	120.6
C5A—C1A—H1A	120.2	C5B—C1B—H1B	120.6
C1A—C2A—C3A	117.4 (3)	C1B—C2B—C3B	117.3 (3)
C1A—C2A—H2A	121.3	C1B—C2B—H2B	121.4
C3A—C2A—H2A	121.3	C3B—C2B—H2B	121.4
N1A—C3A—C2A	124.8 (3)	N1B—C3B—C2B	124.7 (3)
N1A—C3A—Cl1A	114.8 (2)	N1B—C3B—Cl1B	115.0 (3)
C2A—C3A—Cl1A	120.4 (2)	C2B—C3B—Cl1B	120.2 (3)
N1A—C4A—C5A	122.4 (3)	N1B—C4B—C5B	122.7 (3)
N1A—C4A—Cl2A	113.8 (2)	N1B—C4B—Cl2B	115.3 (2)
C5A—C4A—Cl2A	123.8 (2)	C5B—C4B—Cl2B	122.0 (2)
C1A—C5A—C4A	118.4 (3)	C4B—C5B—C1B	119.1 (3)
C1A—C5A—N2A	118.2 (3)	C4B—C5B—N2B	122.5 (3)
C4A—C5A—N2A	123.3 (3)	C1B—C5B—N2B	118.4 (3)

C5A—C1A—C2A—C3A	0.9 (5)	C5B—C1B—C2B—C3B	0.0 (5)
C4A—N1A—C3A—C2A	0.0 (5)	C4B—N1B—C3B—C2B	1.5 (5)
C4A—N1A—C3A—Cl1A	−180.0 (3)	C4B—N1B—C3B—Cl1B	179.7 (2)
C1A—C2A—C3A—N1A	−0.6 (6)	C1B—C2B—C3B—N1B	−1.1 (6)
C1A—C2A—C3A—Cl1A	179.4 (3)	C1B—C2B—C3B—Cl1B	−179.2 (3)
C3A—N1A—C4A—C5A	0.3 (5)	C3B—N1B—C4B—C5B	−0.9 (5)
C3A—N1A—C4A—Cl2A	178.0 (2)	C3B—N1B—C4B—Cl2B	−179.1 (2)
C2A—C1A—C5A—C4A	−0.6 (5)	N1B—C4B—C5B—C1B	0.0 (5)
C2A—C1A—C5A—N2A	179.3 (3)	Cl2B—C4B—C5B—C1B	178.1 (3)
N1A—C4A—C5A—C1A	0.0 (5)	N1B—C4B—C5B—N2B	−178.8 (3)
Cl2A—C4A—C5A—C1A	−177.5 (3)	Cl2B—C4B—C5B—N2B	−0.7 (5)
N1A—C4A—C5A—N2A	−179.9 (3)	C2B—C1B—C5B—C4B	0.5 (5)
Cl2A—C4A—C5A—N2A	2.6 (5)	C2B—C1B—C5B—N2B	179.3 (3)
O2A—N2A—C5A—C1A	−153.8 (3)	O2B—N2B—C5B—C4B	−44.8 (5)
O1A—N2A—C5A—C1A	25.6 (4)	O1B—N2B—C5B—C4B	135.7 (4)
O2A—N2A—C5A—C4A	26.1 (5)	O2B—N2B—C5B—C1B	136.4 (3)
O1A—N2A—C5A—C4A	−154.5 (3)	O1B—N2B—C5B—C1B	−43.0 (5)

Experimental details

Crystal data
Chemical formula	C₅H₂Cl₂N₂O₂
M_r	192.99
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	7.9021 (8), 19.166 (2), 11.0987 (9)
β (°)	122.072 (5)
V (Å³)	1424.4 (2)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.85
Crystal size (mm)	0.40 × 0.27 × 0.24

Data collection
Diffractometer	Bruker SMART APEXII DUO CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.727, 0.821
No. of measured, independent and observed [I > 2σ(I)] reflections	16845, 4817, 2323
R_int	0.060
(sin θ/λ)_max (Å⁻¹)	0.741

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.067, 0.180, 1.08
No. of reflections	4817
No. of parameters	199
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.55, −0.42

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Footnotes

‡Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

The authors thank Universiti Sains Malaysia (USM) for the Research University Grant (1001/PFIZIK/811160). SA thanks the Malaysian Government and USM for the award of a research scholarship. AMI thanks the Department of Atomic Energy, Board for Research in Nuclear Sciences, Government of India for a Young Scientist award.

References

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