organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

6-Chloro-3-nitro-N-(propan-2-yl)pyridin-2-amine

aState Key Laboratory of Biotherapy and Cancer Center, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, People's Republic of China, and bDepartment of Applied Chemistry, College of Chemical Engineering, Sichuan University, Chengdu 610041, People's Republic of China
*Correspondence e-mail: xieym@scu.edu.cn

(Received 23 February 2011; accepted 12 May 2011; online 20 May 2011)

There are two mol­ecules in the asymmetric unit mol­ecule of the title compound, C8H10ClN3O2. Intra­molecular N—H⋯O hydrogen bonds stabilize the mol­ecular structure. There are no classical inter­molecular hydrogen bonds in the crystal structure.

Related literature

For the biological activity of 6-chloro-N-isopropyl-3-nitro­pyridin-2-amine derivatives, see: Lan et al. (2010[Lan, P., Chen, W. N., Xiao, G. K., Sun, P. H. & Chen, W. M. (2010). Bioorg. Med. Chem. Lett. 20, 6764-6772.]); Bavetsias et al. (2010[Bavetsias, V., Large, J. M., Sun, C., Bouloc, N., Kosmopoulou, M., Matteucci, M., Wilsher, N. E., Martins, V., Reynisson, J., Atrash, B., Faisal, A., Urban, F., Valenti, M., Brandon, A. H., Box, G., Raynaud, F. I., Workman, P., Eccles, S. A., Richard, B., Julian, L. S. & McDonald, E. (2010). J. Med. Chem. 53, 5213-5228.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans 2, pp. 1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C8H10ClN3O2

  • Mr = 215.64

  • Triclinic, [P \overline 1]

  • a = 7.4283 (8) Å

  • b = 8.9573 (10) Å

  • c = 15.4301 (17) Å

  • α = 89.672 (9)°

  • β = 86.252 (9)°

  • γ = 78.860 (9)°

  • V = 1005.16 (19) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.36 mm−1

  • T = 295 K

  • 0.28 × 0.23 × 0.18 mm

Data collection
  • Oxford Diffraction Xcalibur Eos diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2006[Oxford Diffraction (2006). CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, England.]) Tmin = 0.971, Tmax = 1.0

  • 8239 measured reflections

  • 4073 independent reflections

  • 2773 reflections with I > 2σ(I)

  • Rint = 0.022

Refinement
  • R[F2 > 2σ(F2)] = 0.061

  • wR(F2) = 0.149

  • S = 1.07

  • 4073 reflections

  • 257 parameters

  • H-atom parameters constrained

  • Δρmax = 0.24 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2⋯O2 0.86 2.02 2.660 (3) 130
N5—H5⋯O3 0.86 2.01 2.653 (3) 130

Data collection: CrysAlis PRO (Oxford Diffraction, 2006[Oxford Diffraction (2006). CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]); software used to prepare material for publication: OLEX2.

Supporting information


Comment top

6–Chloro–N–isopropyl–3–nitropyridin–2–amine derivatives are of great importance owing to their anticancer activity (Lan et al., 2010; Bavetsias et al., 2010). The title compound is one of the key intermediates in our synthetic investigations of anticancer drugs. Now we synthesized the title compound and report here its molecular and crystal structures. In the title compound, C8H10ClN3O2, (Fig. 1), the bond lengths and angles are within normal ranges (Allen et al., 1987). In crystal, there are two molecules of the compound observed in the asymmetric unit. The intramolecular hydrogen bond N2—H2···O2 (N2···O2 = 2.660Å) stabilizes the almost coplanar arrangement of the N2—C5—C4—N3—O2 plane and pyridine ring. And there are no classical hydrogen bonds observed in the crystall packing (Fig. 2).

Related literature top

For the biological activity of 6-chloro-N-isopropyl-3-nitropyridin-2-amine derivatives, see: Lan et al. (2010); Bavetsias et al. (2010). For bond-length data, see: Allen et al. (1987).

Experimental top

A solution of 0.58 g (3.0 mmol) of 2,6–dichloro–3–nitropyridine in 20 ml of dichloromethane was stirred in the ice–water bath for a few minutes, then 0.38 ml (4.5 mmol) isopropylamine was added dropwise. The reaction was stirred in the ice–water bath for 4 h, concentrated under reduced pressure and purified by silica gel column chromatography. Crystals suitable for X–ray analysis were obtained by slow evaporation from a solution of dichloromethane.

Refinement top

All H atoms were positioned geometrically and refined as riding (C—H = 0.93Å–0.98Å, N—H = 0.86Å) and allowed to ride on their parent atoms, with Uiso(H) = 1.2–1.5Ueq(parent).

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2006); cell refinement: CrysAlis PRO (Oxford Diffraction, 2006); data reduction: CrysAlis PRO (Oxford Diffraction, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. Intramolecular hydrogen bonds are presented by blue lines.
[Figure 2] Fig. 2. A packing diagram of the title compound.
6-Chloro-3-nitro-N-(propan-2-yl)pyridin-2-amine top
Crystal data top
C8H10ClN3O2Z = 4
Mr = 215.64F(000) = 448
Triclinic, P1Dx = 1.425 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.7107 Å
a = 7.4283 (8) ÅCell parameters from 2782 reflections
b = 8.9573 (10) Åθ = 3.0–29.2°
c = 15.4301 (17) ŵ = 0.36 mm1
α = 89.672 (9)°T = 295 K
β = 86.252 (9)°Block, colourless
γ = 78.860 (9)°0.28 × 0.23 × 0.18 mm
V = 1005.16 (19) Å3
Data collection top
Oxford Diffraction Xcalibur Eos
diffractometer
4073 independent reflections
Radiation source: fine-focus sealed tube2773 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.022
Detector resolution: 16.0874 pixels mm-1θmax = 26.4°, θmin = 3.0°
ω scansh = 98
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2006)
k = 1111
Tmin = 0.971, Tmax = 1.0l = 1919
8239 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.061Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.149H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0511P)2 + 0.4285P]
where P = (Fo2 + 2Fc2)/3
4073 reflections(Δ/σ)max < 0.001
257 parametersΔρmax = 0.24 e Å3
0 restraintsΔρmin = 0.21 e Å3
Crystal data top
C8H10ClN3O2γ = 78.860 (9)°
Mr = 215.64V = 1005.16 (19) Å3
Triclinic, P1Z = 4
a = 7.4283 (8) ÅMo Kα radiation
b = 8.9573 (10) ŵ = 0.36 mm1
c = 15.4301 (17) ÅT = 295 K
α = 89.672 (9)°0.28 × 0.23 × 0.18 mm
β = 86.252 (9)°
Data collection top
Oxford Diffraction Xcalibur Eos
diffractometer
4073 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2006)
2773 reflections with I > 2σ(I)
Tmin = 0.971, Tmax = 1.0Rint = 0.022
8239 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0610 restraints
wR(F2) = 0.149H-atom parameters constrained
S = 1.07Δρmax = 0.24 e Å3
4073 reflectionsΔρmin = 0.21 e Å3
257 parameters
Special details top

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 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
xyzUiso*/Ueq
Cl10.27337 (14)0.24866 (9)0.55983 (6)0.0755 (3)
Cl20.22248 (13)0.27284 (9)0.95299 (6)0.0649 (3)
O10.2452 (5)0.3317 (3)0.30153 (16)0.1036 (10)
O20.2403 (4)0.4488 (3)0.42175 (16)0.0911 (9)
O30.3152 (4)0.9485 (3)1.08072 (16)0.0773 (7)
O40.3156 (4)0.8329 (3)1.20304 (15)0.0806 (8)
N10.2670 (3)0.0404 (3)0.55475 (14)0.0438 (6)
N20.2640 (4)0.2945 (3)0.56967 (15)0.0510 (6)
H20.26460.38180.54640.061*
N30.2445 (4)0.3306 (4)0.38070 (18)0.0692 (8)
N40.2595 (3)0.5533 (2)0.95342 (14)0.0420 (5)
N50.2928 (4)0.8005 (3)0.93459 (15)0.0504 (6)
H50.30870.88490.95620.060*
N60.3082 (4)0.8333 (3)1.12380 (17)0.0573 (7)
C10.2645 (4)0.0767 (3)0.5049 (2)0.0476 (7)
C20.2568 (4)0.0768 (4)0.4162 (2)0.0576 (8)
H2A0.25600.16520.38500.069*
C30.2504 (4)0.0606 (4)0.3764 (2)0.0563 (8)
H30.24560.06760.31640.068*
C40.2512 (4)0.1893 (3)0.42550 (18)0.0487 (7)
C50.2595 (4)0.1783 (3)0.51714 (17)0.0421 (6)
C60.2678 (4)0.2846 (3)0.66435 (17)0.0452 (7)
H60.35560.19260.67830.054*
C70.0831 (4)0.2722 (4)0.7059 (2)0.0684 (9)
H7B0.00620.35970.69120.103*
H7C0.08940.26730.76790.103*
H7A0.04790.18180.68530.103*
C80.3374 (6)0.4205 (4)0.6968 (2)0.0769 (11)
H8A0.45510.42370.66800.115*
H8C0.34930.41210.75830.115*
H8B0.25200.51200.68470.115*
C90.2499 (4)0.4388 (3)1.00420 (19)0.0439 (7)
C100.2613 (4)0.4363 (3)1.0939 (2)0.0503 (7)
H100.25560.34941.12640.060*
C110.2814 (4)0.5690 (4)1.13095 (19)0.0493 (7)
H110.28920.57461.19070.059*
C120.2901 (4)0.6956 (3)1.08053 (18)0.0428 (6)
C130.2804 (4)0.6865 (3)0.98920 (18)0.0405 (6)
C140.2811 (4)0.7920 (3)0.84014 (18)0.0481 (7)
H140.35040.69250.82010.058*
C150.0870 (5)0.8048 (6)0.8159 (2)0.0928 (14)
H15C0.01660.90220.83410.139*
H15B0.03440.72580.84390.139*
H15A0.08540.79460.75400.139*
C160.3737 (5)0.9121 (4)0.7985 (2)0.0737 (10)
H16A0.37450.90370.73650.111*
H16B0.49780.89820.81560.111*
H16C0.30781.01100.81690.111*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.1077 (7)0.0471 (5)0.0766 (7)0.0291 (5)0.0014 (5)0.0021 (4)
Cl20.0873 (6)0.0453 (5)0.0662 (6)0.0228 (4)0.0058 (4)0.0016 (4)
O10.177 (3)0.092 (2)0.0360 (15)0.0075 (19)0.0197 (17)0.0146 (14)
O20.164 (3)0.0536 (15)0.0507 (16)0.0076 (16)0.0119 (16)0.0113 (13)
O30.128 (2)0.0505 (14)0.0553 (15)0.0203 (14)0.0114 (14)0.0059 (12)
O40.118 (2)0.0906 (19)0.0381 (14)0.0327 (15)0.0006 (13)0.0173 (13)
N10.0527 (14)0.0420 (13)0.0369 (13)0.0108 (10)0.0001 (11)0.0027 (11)
N20.0850 (18)0.0355 (12)0.0317 (13)0.0100 (12)0.0043 (12)0.0031 (10)
N30.096 (2)0.0656 (19)0.0395 (17)0.0025 (16)0.0126 (15)0.0071 (15)
N40.0463 (13)0.0424 (13)0.0370 (13)0.0089 (10)0.0009 (10)0.0026 (11)
N50.0793 (18)0.0376 (13)0.0359 (13)0.0146 (12)0.0054 (12)0.0011 (11)
N60.0691 (18)0.0601 (17)0.0418 (16)0.0106 (13)0.0013 (13)0.0112 (14)
C10.0488 (17)0.0441 (16)0.0514 (19)0.0130 (13)0.0023 (13)0.0034 (14)
C20.061 (2)0.061 (2)0.051 (2)0.0123 (15)0.0064 (15)0.0181 (17)
C30.059 (2)0.071 (2)0.0363 (17)0.0060 (16)0.0079 (14)0.0083 (16)
C40.0536 (18)0.0546 (18)0.0356 (16)0.0038 (14)0.0066 (13)0.0015 (14)
C50.0476 (16)0.0429 (16)0.0344 (15)0.0051 (12)0.0022 (12)0.0028 (12)
C60.0665 (19)0.0372 (15)0.0311 (15)0.0067 (13)0.0063 (13)0.0017 (12)
C70.069 (2)0.083 (2)0.049 (2)0.0039 (18)0.0027 (17)0.0019 (18)
C80.129 (3)0.054 (2)0.053 (2)0.028 (2)0.016 (2)0.0034 (17)
C90.0434 (16)0.0430 (16)0.0451 (17)0.0083 (12)0.0017 (13)0.0028 (13)
C100.0507 (18)0.0546 (18)0.0471 (18)0.0143 (14)0.0029 (14)0.0154 (15)
C110.0485 (17)0.067 (2)0.0323 (16)0.0125 (14)0.0005 (12)0.0043 (14)
C120.0435 (16)0.0474 (16)0.0367 (16)0.0073 (12)0.0008 (12)0.0055 (13)
C130.0426 (15)0.0404 (15)0.0367 (15)0.0037 (11)0.0007 (12)0.0014 (12)
C140.0665 (19)0.0433 (16)0.0363 (16)0.0139 (14)0.0075 (14)0.0038 (13)
C150.072 (3)0.149 (4)0.059 (2)0.024 (3)0.011 (2)0.024 (3)
C160.110 (3)0.068 (2)0.051 (2)0.036 (2)0.005 (2)0.0099 (18)
Geometric parameters (Å, º) top
Cl1—C11.746 (3)C6—H60.9800
Cl2—C91.740 (3)C6—C71.500 (4)
O1—N31.221 (3)C6—C81.511 (4)
O2—N31.231 (3)C7—H7B0.9600
O3—N61.232 (3)C7—H7C0.9600
O4—N61.228 (3)C7—H7A0.9600
N1—C11.308 (3)C8—H8A0.9600
N1—C51.355 (3)C8—H8C0.9600
N2—H20.8600C8—H8B0.9600
N2—C51.329 (3)C9—C101.392 (4)
N2—C61.465 (3)C10—H100.9300
N3—C41.432 (4)C10—C111.360 (4)
N4—C91.297 (3)C11—H110.9300
N4—C131.357 (3)C11—C121.381 (4)
N5—H50.8600C12—C131.420 (4)
N5—C131.333 (3)C14—H140.9800
N5—C141.469 (3)C14—C151.496 (4)
N6—C121.438 (4)C14—C161.504 (4)
C1—C21.374 (4)C15—H15C0.9600
C2—H2A0.9300C15—H15B0.9600
C2—C31.365 (4)C15—H15A0.9600
C3—H30.9300C16—H16A0.9600
C3—C41.384 (4)C16—H16B0.9600
C4—C51.421 (4)C16—H16C0.9600
O1—N3—O2120.7 (3)C6—C8—H8C109.5
O1—N3—C4119.2 (3)C6—C8—H8B109.5
O2—N3—C4120.1 (3)C7—C6—H6108.1
O3—N6—C12119.4 (2)C7—C6—C8112.7 (3)
O4—N6—O3121.6 (3)H7B—C7—H7C109.5
O4—N6—C12118.9 (3)H7B—C7—H7A109.5
N1—C1—Cl1114.6 (2)H7C—C7—H7A109.5
N1—C1—C2126.9 (3)C8—C6—H6108.1
N1—C5—C4118.8 (2)H8A—C8—H8C109.5
N2—C5—N1116.6 (2)H8A—C8—H8B109.5
N2—C5—C4124.6 (3)H8C—C8—H8B109.5
N2—C6—H6108.1C9—N4—C13118.6 (2)
N2—C6—C7111.4 (2)C9—C10—H10122.1
N2—C6—C8108.3 (2)C10—C9—Cl2118.0 (2)
N4—C9—Cl2115.5 (2)C10—C11—H11119.7
N4—C9—C10126.5 (3)C10—C11—C12120.5 (3)
N4—C13—C12118.9 (2)C11—C10—C9115.7 (3)
N5—C13—N4116.6 (2)C11—C10—H10122.1
N5—C13—C12124.4 (2)C11—C12—N6117.8 (3)
N5—C14—H14107.9C11—C12—C13119.7 (3)
N5—C14—C15111.9 (3)C12—C11—H11119.7
N5—C14—C16108.4 (2)C13—N5—H5117.7
C1—N1—C5118.3 (2)C13—N5—C14124.6 (2)
C1—C2—H2A122.0C13—C12—N6122.5 (3)
C2—C1—Cl1118.4 (2)C14—N5—H5117.7
C2—C3—H3120.0C14—C15—H15C109.5
C2—C3—C4120.0 (3)C14—C15—H15B109.5
C3—C2—C1116.0 (3)C14—C15—H15A109.5
C3—C2—H2A122.0C14—C16—H16A109.5
C3—C4—N3117.8 (3)C14—C16—H16B109.5
C3—C4—C5120.0 (3)C14—C16—H16C109.5
C4—C3—H3120.0C15—C14—H14107.9
C5—N2—H2117.6C15—C14—C16112.8 (3)
C5—N2—C6124.8 (2)H15C—C15—H15B109.5
C5—C4—N3122.2 (3)H15C—C15—H15A109.5
C6—N2—H2117.6H15B—C15—H15A109.5
C6—C7—H7B109.5C16—C14—H14107.9
C6—C7—H7C109.5H16A—C16—H16B109.5
C6—C7—H7A109.5H16A—C16—H16C109.5
C6—C8—H8A109.5H16B—C16—H16C109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···O20.862.022.660 (3)130
N5—H5···O30.862.012.653 (3)130

Experimental details

Crystal data
Chemical formulaC8H10ClN3O2
Mr215.64
Crystal system, space groupTriclinic, P1
Temperature (K)295
a, b, c (Å)7.4283 (8), 8.9573 (10), 15.4301 (17)
α, β, γ (°)89.672 (9), 86.252 (9), 78.860 (9)
V3)1005.16 (19)
Z4
Radiation typeMo Kα
µ (mm1)0.36
Crystal size (mm)0.28 × 0.23 × 0.18
Data collection
DiffractometerOxford Diffraction Xcalibur Eos
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Oxford Diffraction, 2006)
Tmin, Tmax0.971, 1.0
No. of measured, independent and
observed [I > 2σ(I)] reflections
8239, 4073, 2773
Rint0.022
(sin θ/λ)max1)0.625
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.061, 0.149, 1.07
No. of reflections4073
No. of parameters257
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.24, 0.21

Computer programs: CrysAlis PRO (Oxford Diffraction, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), OLEX2 (Dolomanov et al., 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···O20.862.022.660 (3)130
N5—H5···O30.862.012.653 (3)130
 

Acknowledgements

We thank the Analytical and Testing Center of Sichuan University for the X–ray measurements.

References

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First citationBavetsias, V., Large, J. M., Sun, C., Bouloc, N., Kosmopoulou, M., Matteucci, M., Wilsher, N. E., Martins, V., Reynisson, J., Atrash, B., Faisal, A., Urban, F., Valenti, M., Brandon, A. H., Box, G., Raynaud, F. I., Workman, P., Eccles, S. A., Richard, B., Julian, L. S. & McDonald, E. (2010). J. Med. Chem. 53, 5213–5228.  Web of Science CrossRef CAS PubMed Google Scholar
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