2-Methyl-6-nitro-2H-indazole

Abstract

In the title compound, C₈H₇N₃O₂, the mol­ecular skeleton is almost planar with a maximum deviation of 0.0484 (9) Å for the methyl C atom. In the crystal, weak inter­molecular C—H⋯N and C—H⋯O hydrogen bonds help to establish the packing.

Related literature

For the synthesis, see: Sorbera et al. (2006 ▶); Balardi et al. (1997 ▶). For related structures, see: Qi et al. (2010 ▶); Chen et al. (2009 ▶). For applications of indazole derivatives, see, for example: Li et al. (2008 ▶).

Experimental

Crystal data

• C₈H₇N₃O₂

• M _r = 177.17

• Monoclinic,

• a = 3.793 (3) Å

• b = 12.200 (8) Å

• c = 16.675 (11) Å

• β = 95.722 (9)°

• V = 767.7 (9) ų

• Z = 4

• Mo Kα radiation

• μ = 0.12 mm⁻¹

• T = 113 K

• 0.40 × 0.20 × 0.10 mm

Data collection

• Rigaku Saturn724 CCD diffractometer

• Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005 ▶) T _min = 0.956, T _max = 0.989

• 7726 measured reflections

• 1802 independent reflections

• 1317 reflections with I > 2σ(I)

• R _int = 0.039

Refinement

• R[F ² > 2σ(F ²)] = 0.035

• wR(F ²) = 0.092

• S = 1.03

• 1802 reflections

• 119 parameters

• H-atom parameters constrained

• Δρ_max = 0.28 e Å⁻³

• Δρ_min = −0.23 e Å⁻³

Data collection: CrystalClear (Rigaku/MSC, 2005 ▶); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: CrystalStructure (Rigaku/MSC, 2005 ▶).

Supplementary Material

Supplementary material file. DOI: 10.1107/S1600536811019374/cv5096Isup3.cdx

Supplementary material file. DOI: 10.1107/S1600536811019374/cv5096Isup4.cml

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
C2—H2⋯N2i	0.95	2.52	3.446 (2)	164
C7—H7⋯O2ii	0.95	2.56	3.500 (2)	169
C8—H8A⋯O2iii	0.98	2.61	3.549 (2)	161
C8—H8B⋯O1ii	0.98	2.51	3.491 (2)	174

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

supplementary crystallographic information

Comment

Some derivatives of indazole are important intermediates in the synthesis of drugs (Li et al. 2008). Herewith we report the crystal structure of the tile compound (I), which is an intermediate in the synthesis of the antitumor agent pazopanib.

In (I) (Fig. 1), the bond lengths and angles are normal and comparable with those reported for related compounds (Qi et al., 2010; Chen et al., 2009). Rings N2/N3/C7/C6/C1 and C1—C6 are almost coplanar forming a dihedral angle 1.08 (7) °. The indazole ring system is almost planar with the maximal deviation of 0.0118 (7) Å for atom N3. Nitro group is twisted at 0.93 (16)° from the plane of the attached indazole ring system.

In the crystal structure, weak intermolecular C—H···N and C—H···O hydrogen bonds (Table 1) help to establish the packing.

Experimental

The title compound was prepared according to Sorbera et al. (2006) and Balardi et al. (1997). 6-Nitro-1H-indazole (2 g) was dissolved in regurgitant dichloromethane (30 ml), then dimethyl sulfate (1.7 ml) and dimethyl sulfoxide (2 ml) were introduced. The mixture was heated to reflux and stayed for 12 h. The reaction mixture was washed with saturated sodium bicarbonate (10 ml) and then extracted with dichloromethane (20 ml), dried with sodium sulfate and evaporated, to give yellow solid (78% yield). Crystals suitable for X-ray analysis were obtained by slow evaporation of a dichloromethane.

Refinement

H atoms were positioned geometrically, with C—H = 0.95 and 0.98 Å for indazole and methyl H, and refined as riding atoms, with U_iso(H) = 1.2U_eq(C) or 1.5U_eq(C_methyl).

Figures

Fig. 1.

The molecular structure of (I), with the atom-numbering scheme and 50% probability displacement ellipsoids.

Crystal data

C8H7N3O2	F(000) = 368
Mr = 177.17	Dx = 1.533 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2636 reflections
a = 3.793 (3) Å	θ = 2.1–28.0°
b = 12.200 (8) Å	µ = 0.12 mm−1
c = 16.675 (11) Å	T = 113 K
β = 95.722 (9)°	Prism, colourless
V = 767.7 (9) Å3	0.40 × 0.20 × 0.10 mm
Z = 4

Data collection

Rigaku Saturn724 CCD diffractometer	1802 independent reflections
Radiation source: rotating anode	1317 reflections with I > 2σ(I)
multilayer	Rint = 0.039
Detector resolution: 14.22 pixels mm-1	θmax = 27.9°, θmin = 2.1°
ω and φ scans	h = −4→4
Absorption correction: multi-scan (CrystalClear; Rigaku/MSC, 2005)	k = −15→16
Tmin = 0.956, Tmax = 0.989	l = −21→21
7726 measured reflections

Refinement

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)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.092	H-atom parameters constrained
S = 1.03	w = 1/[σ2(Fo2) + (0.05P)2] where P = (Fo2 + 2Fc2)/3
1802 reflections	(Δ/σ)max = 0.001
119 parameters	Δρmax = 0.28 e Å−3
0 restraints	Δρmin = −0.23 e Å−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.0001 (2)	0.40192 (7)	1.13521 (6)	0.0330 (3)
O2	−0.1008 (2)	0.23042 (7)	1.15673 (5)	0.0285 (2)
N1	0.0034 (2)	0.30444 (8)	1.11496 (6)	0.0204 (2)
N2	0.2860 (2)	0.04933 (8)	0.90394 (6)	0.0191 (2)
N3	0.4265 (2)	0.07413 (8)	0.83460 (6)	0.0189 (2)
C1	0.2577 (3)	0.14834 (9)	0.93942 (7)	0.0164 (3)
C2	0.1284 (3)	0.16936 (9)	1.01433 (7)	0.0172 (3)
H2	0.0426	0.1128	1.0463	0.021*
C3	0.1351 (3)	0.27717 (9)	1.03783 (7)	0.0172 (3)
C4	0.2556 (3)	0.36516 (9)	0.99200 (7)	0.0197 (3)
H4	0.2521	0.4380	1.0120	0.024*
C5	0.3767 (3)	0.34458 (9)	0.91902 (7)	0.0202 (3)
H5	0.4565	0.4026	0.8874	0.024*
C6	0.3805 (3)	0.23462 (9)	0.89161 (7)	0.0175 (3)
C7	0.4868 (3)	0.18162 (9)	0.82402 (7)	0.0197 (3)
H7	0.5827	0.2147	0.7794	0.024*
C8	0.5084 (3)	−0.01456 (9)	0.78106 (8)	0.0225 (3)
H8A	0.6589	−0.0687	0.8114	0.034*
H8B	0.6335	0.0150	0.7372	0.034*
H8C	0.2879	−0.0497	0.7586	0.034*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
O1	0.0491 (6)	0.0212 (5)	0.0301 (5)	0.0001 (4)	0.0114 (4)	−0.0077 (4)
O2	0.0399 (5)	0.0249 (5)	0.0227 (5)	−0.0030 (4)	0.0126 (4)	0.0002 (4)
N1	0.0211 (5)	0.0207 (5)	0.0195 (5)	0.0007 (4)	0.0026 (4)	−0.0017 (4)
N2	0.0233 (5)	0.0198 (5)	0.0149 (5)	−0.0002 (4)	0.0058 (4)	0.0000 (4)
N3	0.0200 (5)	0.0216 (5)	0.0155 (5)	0.0003 (4)	0.0040 (4)	0.0004 (4)
C1	0.0147 (5)	0.0172 (5)	0.0171 (6)	0.0000 (4)	0.0004 (4)	0.0013 (4)
C2	0.0182 (6)	0.0172 (5)	0.0163 (6)	−0.0002 (4)	0.0021 (5)	0.0013 (4)
C3	0.0155 (6)	0.0203 (6)	0.0158 (6)	0.0016 (4)	0.0018 (5)	−0.0004 (5)
C4	0.0194 (6)	0.0161 (6)	0.0235 (6)	−0.0009 (4)	0.0010 (5)	0.0008 (5)
C5	0.0194 (6)	0.0189 (6)	0.0222 (6)	−0.0015 (5)	0.0026 (5)	0.0046 (5)
C6	0.0151 (6)	0.0208 (6)	0.0163 (6)	−0.0002 (4)	0.0008 (4)	0.0027 (5)
C7	0.0193 (6)	0.0218 (6)	0.0185 (6)	−0.0013 (5)	0.0036 (5)	0.0033 (5)
C8	0.0262 (6)	0.0234 (6)	0.0190 (6)	0.0016 (5)	0.0073 (5)	−0.0029 (5)

Geometric parameters (Å, °)

O1—N1	1.2367 (14)	C3—C4	1.4194 (17)
O2—N1	1.2294 (14)	C4—C5	1.3662 (19)
N1—C3	1.4639 (17)	C4—H4	0.9500
N2—C1	1.3539 (16)	C5—C6	1.4178 (17)
N2—N3	1.3547 (15)	C5—H5	0.9500
N3—C7	1.3459 (17)	C6—C7	1.3934 (18)
N3—C8	1.4559 (16)	C7—H7	0.9500
C1—C2	1.4102 (18)	C8—H8A	0.9800
C1—C6	1.4265 (17)	C8—H8B	0.9800
C2—C3	1.3719 (17)	C8—H8C	0.9800
C2—H2	0.9500
O2—N1—O1	122.63 (11)	C5—C4—H4	120.2
O2—N1—C3	119.20 (10)	C3—C4—H4	120.2
O1—N1—C3	118.17 (10)	C4—C5—C6	118.44 (11)
C1—N2—N3	103.23 (10)	C4—C5—H5	120.8
C7—N3—N2	114.58 (10)	C6—C5—H5	120.8
C7—N3—C8	126.47 (11)	C7—C6—C5	135.47 (11)
N2—N3—C8	118.91 (10)	C7—C6—C1	104.27 (11)
N2—C1—C2	126.80 (10)	C5—C6—C1	120.25 (11)
N2—C1—C6	111.69 (11)	N3—C7—C6	106.23 (11)
C2—C1—C6	121.50 (11)	N3—C7—H7	126.9
C3—C2—C1	115.41 (10)	C6—C7—H7	126.9
C3—C2—H2	122.3	N3—C8—H8A	109.5
C1—C2—H2	122.3	N3—C8—H8B	109.5
C2—C3—C4	124.70 (12)	H8A—C8—H8B	109.5
C2—C3—N1	118.07 (10)	N3—C8—H8C	109.5
C4—C3—N1	117.22 (10)	H8A—C8—H8C	109.5
C5—C4—C3	119.69 (11)	H8B—C8—H8C	109.5
C1—N2—N3—C7	−0.23 (12)	N1—C3—C4—C5	−179.08 (10)
C1—N2—N3—C8	177.69 (9)	C3—C4—C5—C6	−0.52 (16)
N3—N2—C1—C2	−179.34 (10)	C4—C5—C6—C7	−178.43 (12)
N3—N2—C1—C6	0.13 (12)	C4—C5—C6—C1	0.46 (16)
N2—C1—C2—C3	178.46 (10)	N2—C1—C6—C7	0.01 (12)
C6—C1—C2—C3	−0.96 (15)	C2—C1—C6—C7	179.51 (10)
C1—C2—C3—C4	0.92 (16)	N2—C1—C6—C5	−179.19 (9)
C1—C2—C3—N1	179.81 (9)	C2—C1—C6—C5	0.31 (16)
O2—N1—C3—C2	1.59 (15)	N2—N3—C7—C6	0.24 (12)
O1—N1—C3—C2	−178.04 (10)	C8—N3—C7—C6	−177.50 (10)
O2—N1—C3—C4	−179.44 (9)	C5—C6—C7—N3	178.87 (12)
O1—N1—C3—C4	0.93 (14)	C1—C6—C7—N3	−0.14 (11)
C2—C3—C4—C5	−0.19 (17)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···N2i	0.95	2.52	3.446 (2)	164
C7—H7···O2ii	0.95	2.56	3.500 (2)	169
C8—H8A···O2iii	0.98	2.61	3.549 (2)	161
C8—H8B···O1ii	0.98	2.51	3.491 (2)	174

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