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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 11| November 2012| Page o3171
doi:10.1107/S1600536812042791

3-tert-Butyl-1-(3-nitro­phen­yl)-1H-pyrazol-5-amine

Simón Hernández-Ortega,a* Fernando Cuenú-Cabezas,b Rodrigo Abonia-Gonzálezc and Armando Cabrera-Ortiza

aInstituto de Química, Universidad Nacional Autónoma de México, circuito exterior, ciudad universitaria, México 04510, México, bLaboratorio de Química Inorgánica y Catálisis, Programa de Química, Universidad del Quindio, Avenida Bolivar Calle 12 Norte, Armenia, Colombia, and cDepartamento de Química, Universidad del Valle, A. A. 25360, Cali, Colombia
*Correspondence e-mail: simonho@unam.mx

(Received 10 October 2012; accepted 12 October 2012; online 20 October 2012)

In the title compound, C13H16N4O2, the pyrazole ring forms a dihedral angle of 50.61 (6)° with the 3-nitro-phenyl ring. The plane of the nitro group is twisted by 6.8 (7)° out of the plane of the phenyl ring. In the crystal, the mol­ecules are linked by N—H⋯N and N—H⋯O hydrogen bonds, forming sheets in the bc plane. In addition, a weak C—H⋯N inter­action is observed.

Related literature

For background to pyrazole-based ligands, see; Ahmed et al. (2005[Ahmed, M. S. M., Kobayashi, K. & Mori, A. (2005). Org. Lett. 7, 4487-4489.]); Abonia et al. (2002[Abonia, R., Rengifo, E., Quiroga, J., Insuasty, B., Sanchez, A., Cobo, J., Low, J. N. & Nogueras, M. (2002). Tetrahedron Lett. 43, 5617-5620.], 2004[Abonia, R., Rengifo, E., Quiroga, J., Insuasty, B., Cobo, J. & Nogueras, M. (2004). Tetrahedron, 60, 8839-8843.], 2010[Abonia, R., Castillo, J., Insuasty, B., Quiroga, J., Nogueras, M. & Cobo, J. (2010). Eur. J. Org. Chem. 33, 6454-6463.]); Guerrero et al. (2009[Guerrero, M., Pons, J., Parella, T., Font-Bardia, M., Calvet, T. & Ros, J. (2009). Inorg. Chem. 48, 8736-8750.]); Quiroga et al. (2008[Quiroga, J., Portilla, J., Abonia, R., Insuasty, B., Nogueras, M. & Cobo, J. (2008). Tetrahedron Lett. 49, 6254-6256.]); Schutznerová, et al. (2012[Schutznerová, E., Popa, I., Krystof, V., Koshino, H., Trávnícek, Z., Hradil, P. & Cankar, P. (2012). Tetrahedron, 68, 3996-4002.]). For structure of an isomer of the title compound, see: Low et al. (2004[Low, J. N., Cobo, J., Abonia, R., Quiroga, J. & Glidewell, C. (2004). Acta Cryst. C60, o194-o195.]).

[Scheme 1]

Experimental

Crystal data

  • C13H16N4O2

  • Mr = 260.30

  • Monoclinic, P 21 /c

  • a = 11.9421 (14) Å

  • b = 9.6419 (11) Å

  • c = 11.7694 (13) Å

  • β = 93.504 (2)°

  • V = 1352.6 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 298 K

  • 0.46 × 0.36 × 0.32 mm
Data collection

  • Bruker SMART APEX CCD area-detector diffractometer

  • 14529 measured reflections

  • 2486 independent reflections

  • 2036 reflections with I > 2σ(I)

  • Rint = 0.044
Refinement

  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.115

  • S = 1.05

  • 2486 reflections

  • 181 parameters

  • 2 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.17 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N4—H4A⋯N2i 0.90 (1) 2.23 (1) 3.1195 (17) 172 (2)
N4—H4B⋯O1ii 0.90 (1) 2.39 (1) 3.241 (2) 160 (2)
C14—H14⋯N4iii 0.93 2.54 3.403 (2) 155
Symmetry codes: (i) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (ii) [x, -y-{\script{1\over 2}}, z+{\script{1\over 2}}]; (iii) [-x+1, y-{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: SMART (Bruker, 1999[Bruker (1999). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 1999[Bruker (1999). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812042791/bt6847sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812042791/bt6847Isup2.hkl

checkCIF report


Comment top

The recent past has evidenced an ever-increasing interest in pyrazole based ligands. The interest in such compounds is due, first of all, to their variety of coordination complexes with a great number of metal ions and, second, to their ability to provide an extensive variety of coordination geometries and significant structural nuclearity when introducing different kinds of heteroatoms (Ahmed et al. 2005; Schutznerová et al. 2012). The past few years have seen considerable rise in interest in the design of various pyrazole-based ligands for particular metal binding site (Guerrero et al. 2009).

As a part of our current research work focused on the development of new bioactive heterocyclic compounds and continuing with the use of pyrazolic Schiff bases (Quiroga et al., 2008; Abonia et al. 2002, 2004, 2010), in the synthesis of pyrazolopyrimidines, we want to describe the compound 5-amino-3-tert-butyl-1-(3-nitro-phenyl)-1H-pyrazole (I), which is a structural isomer of a related compound previously reported by Low (Low et al., 2004).

The structure of the title compound is shown in Figure 1. The compound consists of a ring pyrazole substituted by 3-nitro-phenyl ring bonded to N1, amino group in C5 and tertbutyl group in C3. The pyrazole and phenyl rings are not coplanar, they are forming a dihedral angle of 50.61 (6)°. The nitro group is rotated around C14—N3 bond by 6.8 (3)°. These angle values are larger than those described for the isomeric compound 5-amino-3-tertbutyl-1-(4-nitro-phenyl)-1H-pyrazole (Low et al., 2004). In the crystal, the molecules are linked by N—H–N and N—H–O intermolecular hydrogen bonds forming sheets in the bc plane. In additon, a weak intermolecular C-H···N interaction is observed (Figure 2, Table 1).

Related literature top

For background to pyrazole-based ligands, see; Ahmed et al. (2005); Abonia et al. (2002, 2004, 2010); Guerrero et al. (2009); Quiroga et al. (2008); Schutznerová, et al. (2012). For structure of an isomer of the title compound, see: Low et al. (2004).

Experimental top

To a solution of conc hydrochloric acid (3.8 ml) in water (33 ml), 3-nitrophenylhydrazine (1.5001 g, 9.87 mmol) and 4,4-dimethyl-3-oxopentanenitrile (1.8502 g, 14.80 mmol) were added. The mixture was heated at 70 °C for 1 h. Then, conc hydrochloric acid (3.8 ml) was added and the mixture was heated for 1 h more. After cooling, crushed ice was added and neutralized with conc ammonium hydroxide. The resulting solid was filtered under reduced pressure, washed with cold water (3 X 5 ml) and dried at ambient temperature affording the title compound (I) as a yellow solid [yield 1.744 g, 68%, m.p. 375 K]. MS (70 eV) m/z (%): 260 (55), 245 (100), 218 (88), 190 (73). Anal. Calc. for C13H16N4O2; C 59.99; H 6.20; N 21.52%, found C 60.36; H 6.42; N 21.88%. Crystals of the title compound suitable for single-crystal X-ray diffraction were grown by slow diffusion of pentane into a CH2Cl2 solution of the title compound.

Refinement top

The positional parameters of the amino H atom were refined with a distance restraint of 0.90 (1)Å while those of the other H atoms were calculated geometrically (C—H = 0.93–0.98 Å). All H atoms were refined with Uiso(H) = 1.2Ueq of the parent atom.

Computing details top

Data collection: SMART (Bruker, 1999); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); 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).

Figures top
[Figure 1] Fig. 1. Structure of (I), with the numbering scheme. The displacement ellipsoids are drawn to 40% of probability.
[Figure 2] Fig. 2. The crystal packing of (I), only the H atoms involved in intermolecular interaction were drawn.
3-tert-Butyl-1-(3-nitrophenyl)-1H-pyrazol-5-amine top
Crystal data top
C13H16N4O2F(000) = 552
Mr = 260.30Dx = 1.278 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 7587 reflections
a = 11.9421 (14) Åθ = 2.7–25.3°
b = 9.6419 (11) ŵ = 0.09 mm−1
c = 11.7694 (13) ÅT = 298 K
β = 93.504 (2)°Prism, orange
V = 1352.6 (3) Å30.46 × 0.36 × 0.32 mm
Z = 4
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer		2036 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.044
Graphite monochromatorθmax = 25.4°, θmin = 2.7°
Detector resolution: 0.83 pixels mm-1h = −14→14
ω scansk = −11→11
14529 measured reflectionsl = −14→14
2486 independent 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)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.115H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.0644P)2 + 0.1233P]
where P = (Fo2 + 2Fc2)/3
2486 reflections(Δ/σ)max < 0.001
181 parametersΔρmax = 0.17 e Å−3
2 restraintsΔρmin = −0.17 e Å−3
Crystal data top
C13H16N4O2V = 1352.6 (3) Å3
Mr = 260.30Z = 4
Monoclinic, P21/cMo Kα radiation
a = 11.9421 (14) ŵ = 0.09 mm−1
b = 9.6419 (11) ÅT = 298 K
c = 11.7694 (13) Å0.46 × 0.36 × 0.32 mm
β = 93.504 (2)°
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer		2036 reflections with I > 2σ(I)
14529 measured reflectionsRint = 0.044
2486 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0402 restraints
wR(F2) = 0.115H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.17 e Å−3
2486 reflectionsΔρmin = −0.17 e Å−3
181 parameters
Special details top

Geometry. All e.s.d.'s (except the those 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
xyzUiso*/Ueq
O10.61664 (14)−0.30475 (15)0.45577 (16)0.1090 (6)
O20.76468 (15)−0.18160 (16)0.45837 (14)0.1006 (5)
N10.71780 (9)0.17992 (11)0.75434 (9)0.0403 (3)
N20.78018 (9)0.26705 (11)0.68907 (9)0.0426 (3)
N30.67228 (15)−0.20551 (15)0.48900 (13)0.0686 (4)
N40.68987 (11)0.12825 (14)0.94996 (10)0.0516 (3)
H4A0.7163 (13)0.1491 (17)1.0213 (9)0.062*
H4B0.6699 (13)0.0411 (11)0.9321 (14)0.062*
C30.84041 (11)0.34268 (13)0.76494 (11)0.0401 (3)
C40.81984 (11)0.30418 (14)0.87650 (11)0.0433 (3)
H40.85230.34210.94330.052*
C50.74255 (11)0.19985 (13)0.86760 (11)0.0400 (3)
C60.91855 (12)0.45492 (15)0.72699 (13)0.0488 (4)
C70.99208 (17)0.3989 (2)0.63582 (17)0.0768 (6)
H7A1.03740.32410.66690.115*
H7B1.03980.47160.61100.115*
H7C0.94530.36570.57230.115*
C80.85048 (16)0.57837 (16)0.67990 (16)0.0698 (5)
H8A0.80510.55000.61380.105*
H8B0.90050.65090.65940.105*
H8C0.80300.61190.73680.105*
C90.99367 (15)0.50386 (18)0.82913 (16)0.0657 (5)
H9A0.94830.54540.88450.098*
H9B1.04640.57090.80440.098*
H9C1.03340.42600.86260.098*
C110.64947 (11)0.07495 (13)0.70143 (11)0.0413 (3)
C120.69297 (12)−0.00946 (14)0.62034 (12)0.0458 (4)
H120.76580.00270.59850.055*
C130.62517 (13)−0.11245 (14)0.57271 (12)0.0490 (4)
C140.51684 (14)−0.13283 (15)0.60126 (14)0.0555 (4)
H140.4727−0.20230.56680.067*
C150.47534 (14)−0.04795 (17)0.68205 (15)0.0598 (4)
H150.4022−0.06030.70320.072*
C160.54076 (12)0.05548 (16)0.73219 (13)0.0535 (4)
H160.51170.11240.78690.064*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.1062 (12)0.0705 (9)0.1473 (15)−0.0008 (8)−0.0181 (10)−0.0588 (10)
O20.1094 (13)0.0912 (11)0.1050 (12)−0.0042 (9)0.0366 (10)−0.0347 (9)
N10.0438 (6)0.0374 (6)0.0390 (6)−0.0066 (5)−0.0035 (5)0.0012 (5)
N20.0464 (7)0.0400 (6)0.0408 (6)−0.0063 (5)−0.0029 (5)0.0030 (5)
N30.0837 (11)0.0507 (8)0.0697 (9)0.0057 (8)−0.0079 (8)−0.0137 (7)
N40.0619 (8)0.0505 (7)0.0418 (7)−0.0070 (6)−0.0016 (6)0.0068 (6)
C30.0411 (7)0.0346 (7)0.0435 (7)0.0009 (6)−0.0056 (6)0.0008 (6)
C40.0487 (8)0.0402 (7)0.0398 (7)−0.0025 (6)−0.0089 (6)−0.0019 (6)
C50.0429 (7)0.0370 (7)0.0393 (7)0.0041 (6)−0.0037 (6)0.0025 (5)
C60.0518 (8)0.0404 (7)0.0530 (8)−0.0076 (6)−0.0062 (7)0.0043 (6)
C70.0860 (13)0.0648 (11)0.0827 (13)−0.0206 (10)0.0292 (11)0.0050 (10)
C80.0834 (12)0.0428 (9)0.0797 (12)−0.0123 (8)−0.0248 (10)0.0123 (8)
C90.0610 (10)0.0575 (10)0.0756 (11)−0.0208 (8)−0.0191 (9)0.0098 (8)
C110.0442 (8)0.0361 (7)0.0426 (7)−0.0044 (6)−0.0060 (6)0.0030 (6)
C120.0460 (8)0.0427 (8)0.0478 (8)−0.0014 (6)−0.0044 (6)0.0011 (6)
C130.0606 (9)0.0365 (7)0.0484 (8)0.0008 (7)−0.0084 (7)−0.0012 (6)
C140.0612 (10)0.0420 (8)0.0611 (9)−0.0129 (7)−0.0132 (8)0.0031 (7)
C150.0495 (9)0.0606 (10)0.0690 (10)−0.0154 (8)−0.0001 (8)−0.0018 (8)
C160.0494 (9)0.0525 (9)0.0585 (9)−0.0054 (7)0.0020 (7)−0.0050 (7)
Geometric parameters (Å, º) top
O1—N31.2159 (19)C7—H7B0.9600
O2—N31.204 (2)C7—H7C0.9600
N1—C51.3613 (17)C8—H8A0.9600
N1—N21.3858 (15)C8—H8B0.9600
N1—C111.4198 (16)C8—H8C0.9600
N2—C31.3297 (17)C9—H9A0.9600
N3—C131.470 (2)C9—H9B0.9600
N4—C51.3735 (18)C9—H9C0.9600
N4—H4A0.901 (9)C11—C121.380 (2)
N4—H4B0.895 (9)C11—C161.382 (2)
C3—C41.4005 (19)C12—C131.378 (2)
C3—C61.5140 (19)C12—H120.9300
C4—C51.3650 (19)C13—C141.370 (2)
C4—H40.9300C14—C151.370 (2)
C6—C81.526 (2)C14—H140.9300
C6—C71.526 (2)C15—C161.377 (2)
C6—C91.530 (2)C15—H150.9300
C7—H7A0.9600C16—H160.9300
C5—N1—N2111.43 (10)C6—C8—H8A109.5
C5—N1—C11127.92 (11)C6—C8—H8B109.5
N2—N1—C11120.20 (10)H8A—C8—H8B109.5
C3—N2—N1104.32 (10)C6—C8—H8C109.5
O2—N3—O1123.17 (17)H8A—C8—H8C109.5
O2—N3—C13118.64 (15)H8B—C8—H8C109.5
O1—N3—C13118.17 (17)C6—C9—H9A109.5
C5—N4—H4A113.3 (11)C6—C9—H9B109.5
C5—N4—H4B115.7 (11)H9A—C9—H9B109.5
H4A—N4—H4B120.1 (16)C6—C9—H9C109.5
N2—C3—C4111.44 (12)H9A—C9—H9C109.5
N2—C3—C6120.78 (12)H9B—C9—H9C109.5
C4—C3—C6127.78 (12)C12—C11—C16120.04 (13)
C5—C4—C3106.26 (12)C12—C11—N1119.55 (12)
C5—C4—H4126.9C16—C11—N1120.40 (13)
C3—C4—H4126.9C13—C12—C11118.00 (13)
N1—C5—C4106.53 (11)C13—C12—H12121.0
N1—C5—N4122.60 (12)C11—C12—H12121.0
C4—C5—N4130.77 (13)C14—C13—C12122.92 (14)
C3—C6—C8109.90 (12)C14—C13—N3118.85 (14)
C3—C6—C7110.23 (12)C12—C13—N3118.23 (14)
C8—C6—C7109.71 (14)C15—C14—C13118.12 (14)
C3—C6—C9109.33 (12)C15—C14—H14120.9
C8—C6—C9108.57 (13)C13—C14—H14120.9
C7—C6—C9109.07 (14)C14—C15—C16120.67 (15)
C6—C7—H7A109.5C14—C15—H15119.7
C6—C7—H7B109.5C16—C15—H15119.7
H7A—C7—H7B109.5C15—C16—C11120.24 (14)
C6—C7—H7C109.5C15—C16—H16119.9
H7A—C7—H7C109.5C11—C16—H16119.9
H7B—C7—H7C109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N4—H4A···N2i0.90 (1)2.23 (1)3.1195 (17)172 (2)
N4—H4B···O1ii0.90 (1)2.39 (1)3.241 (2)160 (2)
C14—H14···N4iii0.932.543.403 (2)155
Symmetry codes: (i) x, −y+1/2, z+1/2; (ii) x, −y−1/2, z+1/2; (iii) −x+1, y−1/2, −z+3/2.

Experimental details

Crystal data
Chemical formulaC13H16N4O2
Mr260.30
Crystal system, space groupMonoclinic, P21/c
Temperature (K)298
a, b, c (Å)11.9421 (14), 9.6419 (11), 11.7694 (13)
β (°) 93.504 (2)
V (Å3)1352.6 (3)
Z4
Radiation typeMo Kα
µ (mm−1)0.09
Crystal size (mm)0.46 × 0.36 × 0.32
Data collection
DiffractometerBruker SMART APEX CCD area-detector
diffractometer
Absorption correction–
No. of measured, independent and
observed [I > 2σ(I)] reflections		14529, 2486, 2036
Rint0.044
(sin θ/λ)max (Å−1)0.603
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.115, 1.05
No. of reflections2486
No. of parameters181
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.17, −0.17

Computer programs: SMART (Bruker, 1999), SAINT (Bruker, 1999), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N4—H4A···N2i0.901 (9)2.225 (10)3.1195 (17)171.6 (15)
N4—H4B···O1ii0.895 (9)2.386 (11)3.241 (2)159.8 (15)
C14—H14···N4iii0.932.543.403 (2)155
Symmetry codes: (i) x, −y+1/2, z+1/2; (ii) x, −y−1/2, z+1/2; (iii) −x+1, y−1/2, −z+3/2.
 

Acknowledgements

FCC and RAG thanks the Universidad del Valle and the Universidad del Quindío for financial support to project 542. ACO thanks the DGAPA–UNAM for financial support (PAPIIT IN203209). SHO thanks the Consejo Superior de Investigaciones Científicas (CSIC) of Spain for the award of a licence for the use of the Cambridge Structural Database.

References

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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 68| Part 11| November 2012| Page o3171
doi:10.1107/S1600536812042791
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