2,3-Dimethyl-6-nitro-2H-indazole

Chen, Y.; Fang, Z.; Wei, P.

doi:10.1107/S1600536809025410

organic compounds

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ISSN: 2056-9890

Volume 65| Part 8| August 2009| Page o1775

doi:10.1107/S1600536809025410

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2,3-Dimethyl-6-nitro-2H-indazole

Yan Chen,^a Zheng Fang ^b ^* and Ping Wei ^a

^aCollege of Biotechnology and Pharmaceutical Engineering, Nanjing University of Technolgy, Xinmofan Road No. 5 Nanjing, Nanjing 210009, People's Republic of China, and ^bSchool of Pharmaceutical Sciences, Nanjing University of Technolgy, Xinmofan Road No. 5 Nanjing, Nanjing 210009, People's Republic of China
^*Correspondence e-mail: fzcpu@163.com

(Received 26 June 2009; accepted 1 July 2009; online 4 July 2009)

In the molecule of the title compound, C₉H₉N₃O₂, the indazole ring system is almost planar [maximum deviation = 0.019 (3) Å for the C atom bearing the nitro group]. In the crystal structure, intermolecular C—H⋯O interactions link the molecules into centrosymmetric dimers, forming R₂²(18) ring motifs. Aromatic π–π contacts between indazole rings [centroid–centroid distances = 3.632 (1) and 3.705 (1) Å] may further stabilize the structure.

Related literature

For a related structure, see: Xu et al. (1999 ). For bond-length data, see: Allen et al. (1987 ). For ring-motifs, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₉H₉N₃O₂
M_r = 191.19
Triclinic, $[P \overline 1]$
a = 6.5800 (13) Å
b = 7.2050 (14) Å
c = 10.752 (2) Å
α = 75.07 (3)°
β = 74.67 (3)°
γ = 66.73 (3)°
V = 444.81 (19) Å³
Z = 2
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 294 K
0.30 × 0.20 × 0.10 mm

Data collection

Enraf–Nonius CAD-4 diffractometer
Absorption correction: ψ scan (North et al., 1968 ) T_min = 0.969, T_max = 0.990
1756 measured reflections
1606 independent reflections
1292 reflections with I > 2σ(I)
R_int = 0.031
3 standard reflections frequency: 120 min intensity decay: 1%

Refinement

R[F² > 2σ(F²)] = 0.054
wR(F²) = 0.154
S = 1.00
1606 reflections
129 parameters
H-atom parameters constrained
Δρ_max = 0.32 e Å⁻³
Δρ_min = −0.25 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1A⋯O2ⁱ	0.96	2.58	3.533 (4)	171
Symmetry code: (i) -x-1, -y+2, -z.

Data collection: CAD-4 Software (Enraf–Nonius, 1989 ); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995 ); 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, 1997 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXL97 and PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809025410/hk2724sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809025410/hk2724Isup2.hkl

checkCIF report

Comment top

Some derivatives of indazole are important chemical materials. We report herein the crystal structure of the title compound.

In the molecule of the title compound (Fig 1), the bond lengths (Allen et al., 1987) and angles are within normal ranges. Rings A (N1/N2/C3/C4/C9) and B (C4-C9) are, of course, planar and the dihedral angle between them is A/B = 0.80 (3)°. The indazole ring system is planar with a maximum deviation of -0.019 (3) Å for atom C6. Atoms O1, O2, N3, C1 and C2 are 0.024 (3), -0.124 (3), -0.038 (3), 0.003 (3) and -0.056 (3) Å away from the plane of the indazole ring system, respectively.

In the crystal structure, weak intermolecular C-H···O interactions (Table 1) link the molecules into centrosymmetric dimers forming R₂²(18) ring motifs (Bernstein et al., 1995) (Fig. 2), in which they may be effective in the stabilization of the structure. The π–π contacts between the indazole rings, Cg1—Cg2ⁱ and Cg2—Cg2ⁱⁱ [symmetry codes: (i) 2 - x, 2 - y, -z, (ii) 2 - x, 1 - y, -z, where Cg1 and Cg2 are centroids of the rings A (N1/N2/C3/C4/C9) and B (C4-C9), respectively] may further stabilize the structure, with centroid-centroid distances of 3.632 (1) and 3.705 (1) Å, respectively.

Related literature top

For a related structure, see: Xu et al. (1999). For bond-length data, see: Allen et al. (1987). For ring-motifs, see: Bernstein et al. (1995).

Experimental top

For the preparation of the title compound, metallic sodium (3.22 g) was dissolved in regurgitant 2-propanol (140 ml). Then, the solution was added to 3-methyl-6-nitro-1H-indazole (13 g) and iodomethane (30 g) was added in small portions. The mixture was refluxed for 5 h. The suspension was cooled to room temperature, filtered and washed with 2-propanol to give yellow solid (yield; 12 g) (Xu et al., 1999). Crystals suitable for X-ray analysis were obtained by slow evaporation of a methanol solution.

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software (Enraf–Nonius, 1989); data reduction: XCAD4 (Harms & Wocadlo, 1995); 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, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 2. A partial packing diagram of the title compound. Hydrogen bonds are shown as dashed lines.

2,3-Dimethyl-6-nitro-2H-indazole top

Crystal data top

C₉H₉N₃O₂	Z = 2
M_r = 191.19	F(000) = 200
Triclinic, P1	D_x = 1.427 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.5800 (13) Å	Cell parameters from 25 reflections
b = 7.2050 (14) Å	θ = 9–13°
c = 10.752 (2) Å	µ = 0.11 mm⁻¹
α = 75.07 (3)°	T = 294 K
β = 74.67 (3)°	Block, colorless
γ = 66.73 (3)°	0.30 × 0.20 × 0.10 mm
V = 444.81 (19) Å³

Data collection top

Enraf–Nonius CAD-4 diffractometer	1292 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.031
Graphite monochromator	θ_max = 25.3°, θ_min = 2.0°
ω/2θ scans	h = 0→7
Absorption correction: ψ scan (North et al., 1968)	k = −7→8
T_min = 0.969, T_max = 0.990	l = −12→12
1756 measured reflections	3 standard reflections every 120 min
1606 independent reflections	intensity decay: 1%

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.054	H-atom parameters constrained
wR(F²) = 0.154	w = 1/[σ²(F_o²) + (0.08P)² + 0.235P] where P = (F_o² + 2F_c²)/3
S = 1.00	(Δ/σ)_max < 0.001
1606 reflections	Δρ_max = 0.32 e Å⁻³
129 parameters	Δρ_min = −0.25 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.059 (12)

Crystal data top

C₉H₉N₃O₂	γ = 66.73 (3)°
M_r = 191.19	V = 444.81 (19) Å³
Triclinic, P1	Z = 2
a = 6.5800 (13) Å	Mo Kα radiation
b = 7.2050 (14) Å	µ = 0.11 mm⁻¹
c = 10.752 (2) Å	T = 294 K
α = 75.07 (3)°	0.30 × 0.20 × 0.10 mm
β = 74.67 (3)°

Data collection top

Enraf–Nonius CAD-4 diffractometer	1292 reflections with I > 2σ(I)
Absorption correction: ψ scan (North et al., 1968)	R_int = 0.031
T_min = 0.969, T_max = 0.990	3 standard reflections every 120 min
1756 measured reflections	intensity decay: 1%
1606 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.054	0 restraints
wR(F²) = 0.154	H-atom parameters constrained
S = 1.00	Δρ_max = 0.32 e Å⁻³
1606 reflections	Δρ_min = −0.25 e Å⁻³
129 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
O1	0.2155 (5)	0.7495 (5)	−0.3831 (2)	0.1020 (9)
O2	−0.1339 (4)	0.7845 (4)	−0.33747 (19)	0.0803 (7)
N1	−0.2315 (3)	0.7731 (3)	0.25319 (18)	0.0469 (5)
N2	−0.3309 (3)	0.7997 (3)	0.15107 (18)	0.0479 (5)
N3	0.0392 (4)	0.7648 (3)	−0.3051 (2)	0.0611 (6)
C1	−0.3707 (5)	0.7880 (5)	0.3829 (2)	0.0660 (8)
H1A	−0.5144	0.8941	0.3758	0.099*
H1B	−0.2979	0.8202	0.4368	0.099*
H1C	−0.3915	0.6594	0.4218	0.099*
C2	0.1367 (5)	0.6977 (4)	0.3176 (3)	0.0601 (7)
H2B	0.0456	0.7087	0.4032	0.090*
H2C	0.2098	0.7971	0.2929	0.090*
H2D	0.2482	0.5625	0.3186	0.090*
C3	−0.0080 (4)	0.7362 (3)	0.2216 (2)	0.0432 (6)
C4	−0.1582 (3)	0.7777 (3)	0.0489 (2)	0.0390 (5)
C5	−0.1637 (4)	0.7888 (3)	−0.0830 (2)	0.0446 (6)
H5A	−0.2966	0.8160	−0.1108	0.054*
C6	0.0376 (4)	0.7573 (3)	−0.1678 (2)	0.0462 (6)
C7	0.2431 (4)	0.7224 (4)	−0.1315 (2)	0.0517 (6)
H7A	0.3741	0.7057	−0.1943	0.062*
C8	0.2482 (4)	0.7134 (3)	−0.0049 (2)	0.0470 (6)
H8A	0.3819	0.6910	0.0204	0.056*
C9	0.0474 (3)	0.7388 (3)	0.0874 (2)	0.0387 (5)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.1021 (19)	0.150 (2)	0.0491 (12)	−0.0512 (17)	0.0174 (12)	−0.0311 (13)
O2	0.1002 (17)	0.0986 (16)	0.0521 (12)	−0.0371 (13)	−0.0217 (11)	−0.0183 (11)
N1	0.0480 (11)	0.0573 (12)	0.0389 (10)	−0.0226 (9)	−0.0063 (8)	−0.0089 (8)
N2	0.0436 (11)	0.0606 (12)	0.0427 (11)	−0.0218 (9)	−0.0069 (8)	−0.0098 (9)
N3	0.0804 (16)	0.0572 (13)	0.0453 (12)	−0.0255 (11)	−0.0051 (12)	−0.0129 (10)
C1	0.0621 (17)	0.095 (2)	0.0422 (14)	−0.0311 (15)	0.0000 (12)	−0.0173 (13)
C2	0.0642 (16)	0.0669 (17)	0.0564 (15)	−0.0235 (13)	−0.0231 (13)	−0.0092 (12)
C3	0.0475 (13)	0.0402 (12)	0.0459 (12)	−0.0177 (9)	−0.0112 (10)	−0.0077 (9)
C4	0.0400 (11)	0.0369 (11)	0.0427 (12)	−0.0162 (9)	−0.0058 (9)	−0.0085 (9)
C5	0.0501 (13)	0.0444 (12)	0.0442 (13)	−0.0207 (10)	−0.0117 (10)	−0.0061 (9)
C6	0.0611 (14)	0.0384 (12)	0.0389 (12)	−0.0202 (10)	−0.0034 (10)	−0.0079 (9)
C7	0.0465 (13)	0.0485 (13)	0.0523 (14)	−0.0148 (10)	0.0048 (10)	−0.0128 (11)
C8	0.0405 (12)	0.0423 (12)	0.0579 (14)	−0.0137 (9)	−0.0079 (10)	−0.0104 (10)
C9	0.0426 (12)	0.0306 (10)	0.0448 (12)	−0.0135 (8)	−0.0098 (9)	−0.0070 (8)

Geometric parameters (Å, º) top

O1—N3	1.222 (3)	C2—H2C	0.9600
O2—N3	1.223 (3)	C2—H2D	0.9600
N1—N2	1.357 (3)	C3—C9	1.389 (3)
N1—C1	1.456 (3)	C4—C5	1.409 (3)
N1—C3	1.350 (3)	C4—C9	1.420 (3)
N2—C4	1.346 (3)	C5—C6	1.366 (3)
N3—C6	1.460 (3)	C5—H5A	0.9300
C1—H1A	0.9600	C6—C7	1.416 (4)
C1—H1B	0.9600	C7—C8	1.354 (3)
C1—H1C	0.9600	C7—H7A	0.9300
C2—C3	1.487 (3)	C8—C9	1.405 (3)
C2—H2B	0.9600	C8—H8A	0.9300

N2—N1—C1	118.6 (2)	N1—C3—C2	124.3 (2)
C3—N1—N2	114.84 (19)	C9—C3—C2	130.3 (2)
C3—N1—C1	126.6 (2)	N2—C4—C5	127.8 (2)
C4—N2—N1	102.99 (17)	N2—C4—C9	111.81 (19)
O1—N3—O2	122.6 (2)	C5—C4—C9	120.4 (2)
O1—N3—C6	118.2 (2)	C6—C5—C4	116.1 (2)
O2—N3—C6	119.2 (2)	C6—C5—H5A	121.9
N1—C1—H1A	109.5	C4—C5—H5A	121.9
N1—C1—H1B	109.5	C5—C6—C7	124.2 (2)
H1A—C1—H1B	109.5	C5—C6—N3	117.7 (2)
N1—C1—H1C	109.5	C7—C6—N3	118.1 (2)
H1A—C1—H1C	109.5	C8—C7—C6	119.7 (2)
H1B—C1—H1C	109.5	C8—C7—H7A	120.1
C3—C2—H2B	109.5	C6—C7—H7A	120.1
C3—C2—H2C	109.5	C7—C8—C9	118.6 (2)
H2B—C2—H2C	109.5	C7—C8—H8A	120.7
C3—C2—H2D	109.5	C9—C8—H8A	120.7
H2B—C2—H2D	109.5	C3—C9—C8	134.1 (2)
H2C—C2—H2D	109.5	C3—C9—C4	105.00 (19)
N1—C3—C9	105.36 (19)	C8—C9—C4	120.9 (2)

C1—N1—N2—C4	179.6 (2)	C2—C3—C9—C8	−2.1 (4)
C3—N1—N2—C4	0.1 (2)	N2—C4—C5—C6	−178.9 (2)
N2—N1—C3—C2	−178.6 (2)	C9—C4—C5—C6	0.9 (3)
N2—N1—C3—C9	0.2 (2)	N2—C4—C9—C3	0.4 (2)
C1—N1—C3—C2	1.9 (4)	N2—C4—C9—C8	−179.25 (18)
C1—N1—C3—C9	−179.3 (2)	C5—C4—C9—C3	−179.41 (19)
N1—N2—C4—C5	179.5 (2)	C5—C4—C9—C8	0.9 (3)
N1—N2—C4—C9	−0.3 (2)	C4—C5—C6—C7	−2.2 (3)
O1—N3—C6—C5	175.6 (2)	C4—C5—C6—N3	179.20 (19)
O1—N3—C6—C7	−3.1 (3)	C5—C6—C7—C8	1.8 (4)
O2—N3—C6—C5	−5.0 (3)	N3—C6—C7—C8	−179.7 (2)
O2—N3—C6—C7	176.4 (2)	C6—C7—C8—C9	0.2 (3)
N1—C3—C9—C4	−0.4 (2)	C7—C8—C9—C3	179.0 (2)
N1—C3—C9—C8	179.3 (2)	C7—C8—C9—C4	−1.4 (3)
C2—C3—C9—C4	178.3 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1A···O2ⁱ	0.96	2.58	3.533 (4)	171

Symmetry code: (i) −x−1, −y+2, −z.

Experimental details

Crystal data
Chemical formula	C₉H₉N₃O₂
M_r	191.19
Crystal system, space group	Triclinic, P1
Temperature (K)	294
a, b, c (Å)	6.5800 (13), 7.2050 (14), 10.752 (2)
α, β, γ (°)	75.07 (3), 74.67 (3), 66.73 (3)
V (Å³)	444.81 (19)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.30 × 0.20 × 0.10

Data collection
Diffractometer	Enraf–Nonius CAD-4 diffractometer
Absorption correction	ψ scan (North et al., 1968)
T_min, T_max	0.969, 0.990
No. of measured, independent and observed [I > 2σ(I)] reflections	1756, 1606, 1292
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.600

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.054, 0.154, 1.00
No. of reflections	1606
No. of parameters	129
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.32, −0.25

Computer programs: CAD-4 Software (Enraf–Nonius, 1989), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1A···O2ⁱ	0.96	2.58	3.533 (4)	171

Symmetry code: (i) −x−1, −y+2, −z.

Acknowledgements

The authors thank the Center of Testing and Analysis, Nanjing University, for support.

References

Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19. CrossRef Web of Science Google Scholar
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
Enraf–Nonius (1989). CAD-4 Software. Enraf–Nonius, Delft, The Netherlands. Google Scholar
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany. Google Scholar
North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351–359. CrossRef 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
Xu, B.-C., Deng, F. & Wang, H.-Z. (1999). Speciality Petro. Chem. pp. 18–20. CAS Google Scholar