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Molecules of the title compound, C13H16N4O2, are linked by one N-H...O hydrogen bond [H...O = 2.47 Å, N...O = 3.326 (2) Å and N-H...O = 166°] and one N-H...N hydrogen bond [H...N = 2.19 Å, N...N = 3.063 (2) Å and N-H...N = 173°] into sheets containing alternating R_2^2(20) and R_6^6(32) rings, both types of which are centrosymmetric.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270104000678/sk1695sup1.cif
Contains datablocks global, I

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S0108270104000678/sk1695Isup2.hkl
Contains datablock I

CCDC reference: 235342

Comment top

The title compound, (I), is a frequently used intermediate for the synthesis of interesting fused pyrazolo[3,4-b]pyridine or similar derivatives. In the molecules of the title compound (Fig. 1), the dihedral angle between the aryl and heterocyclic rings is 33.7 (2)°, possibly controlled in part by the tendency of atom H12 and the amine group bonded to atom C5 to avoid one another. On the other hand, the nitro group is almost coplanar with the adjacent aryl ring, with a dihedral angle between the aryl plane and the C/NO2 plane of only 2.2 (2). Associated with the dihedral angle between the rings, there is negligible evidence for any delocalization of the lone pair at atom N1 into the nitro group to form the polarized structure (Ia). In particular, the C—N distances exocyclic to the aryl ring (Table 1) are typical of their type (Allen et al., 1987), while the C—C bond distances in the aryl ring span the small range 1.378 (3)–1.396 (3) Å, with no sign of quinonoid-type bond fixation. However, there is marked bond fixation within the heterocyclic ring (Table 1), where the C3—C4 and C4—C5 distances differ significantly, as do the N2—C3 and N1—C5 distances. Consistent with the pyramidal nature of atom N5, the bond C5—N5 bond is long for its type. The dihedral angle between the two rings and the conformation adopted by the tert-butyl group render the molecules chiral; however, the space group accommodates equal numbers of the two enantiomeric forms.

The molecules of (I) are linked into sheets by one N—H···O hydrogen bond and one N—H···N hydrogen bond (Table 1), and the sheet-formation is readily analysed by considering the action of each of these hydrogen bonds in turn.

Amine atom N5 in the molecule at (x, y, z) acts as a hydrogen-bond donor, via atom H5B, to nitro atom O142 in the molecule at (1 − x, 1 − y, 1 − z), thereby generating a centrosymmetric R22(20) (Bernstein et al., 1995) dimer centred at (1/2, 1/2, 1/2). The action of the N—H···N hydrogen bond is to link each of these dimers to four adjacent dimers, thereby forming a continuous sheet. Amine atoms N5 at (x, y, z) and (1 − x, 1 − y, 1 − z) both lie in the dimer centred at (1/2, 1/2, 1/2), and these atoms act as hydrogen-bond donors, this time via atom H5A, to atoms N52 in the molecules at (x, 0.5 − y, −0.5 + z) and (1 − x, 0.5 + y, 1.5 − z), respectively, which themselves lie in the dimers centred at (1/2, 0, 0) and (1/2, 1, 1), respectively. Likewise, atoms N52 at (x, y, z) and (1 − x, 1 − y, 1 − z) accept hydrogen bonds from atoms N5 in the molecules at (x, 0.5 − y, 0.5 + z) and (1 − x, 0.5 + y, 0.5 − z), which themselves lie in the dimers centred at (1/2, 0, 1) and (1/2, 1, 0). Propagation by the space group of these two hydrogen bonds then generates a (100) sheet built from alternating R22(20) and R66(32) rings, where both ring types are centrosymmetric (Fig. 2). If the R22 dimers are regarded as the nodes of the resulting net then this is of (4,4) type (Batten & Robson, 1998).

There are no direction-specific interactions between adjacent sheets; in particular, there are neither C—H···π(arene) hydrogen bonds nor aromatic π···π stacking interactions present in the structure. The R66(32) rings are largely occupied by a pair of tert-butyl groups, one pendent from each of the adjacent (100) sheets, and there are no solvent-accessible voids within the structure.

Experimental top

A suspension of equimolar amounts (16 mmol) of 4-nitrophenylhydrazine and 4,4-dimethyl-3-oxopentanenitrile in concentrated HCl (10 ml) and water (20 ml) was stirred at room temperature for 10 min. The volume was then reduced to half the original, concentrated HCl (20 ml) was added, and the resulting mixture was heated with stirring for 15 min. The mixture was then cooled and neutralized with aqueous ammonia. The solid product, (I), was collected and recrystallized from water (yield 90%, m.p. 445 K).

Refinement top

Space group P21/c was uniquely assigned from the systematic absences. All H atoms were located from difference maps, which showed clearly the pyramidal nature of the amine group based on atom N5, and all H atoms then treated as riding atoms, with C—H 0.distances of 95 (aromatic) or 0.98 Å (methyl), and N—H distances of 0.88 Å.

Computing details top

Data collection: KappaCCD Server Software (Nonius, 1997); cell refinement: DENZO–SMN (Otwinowski & Minor, 1997); data reduction: DENZO–SMN; program(s) used to solve structure: OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997) and PRPKAPPA (Ferguson, 1999).

Figures top
[Figure 1] Fig. 1. The molecule of (I), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. A stereoview of part of the crystal structure of (I), showing the formation of a (100) sheet built from alternating R22(20) and R66(32) rings.
5-Amino-3-tert-butyl-1-(4-nitrophenyl)-1H-pyrazole top
Crystal data top
C13H16N4O2F(000) = 552
Mr = 260.30Dx = 1.315 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3001 reflections
a = 5.9581 (2) Åθ = 3.4–27.5°
b = 18.3064 (11) ŵ = 0.09 mm1
c = 12.0776 (7) ÅT = 120 K
β = 93.4150 (12)°Lath, yellow
V = 1314.98 (12) Å30.20 × 0.10 × 0.04 mm
Z = 4
Data collection top
KappaCCD
diffractometer
3001 independent reflections
Radiation source: rotating anode1700 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.071
ϕ scans, and ω scans with κ offsetsθmax = 27.5°, θmin = 3.4°
Absorption correction: multi-scan
(SORTAV; Blessing, 1995, 1997)
h = 77
Tmin = 0.977, Tmax = 0.996k = 2321
14938 measured reflectionsl = 1515
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)] = 0.052Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.124H-atom parameters constrained
S = 0.96 w = 1/[σ2(Fo2) + (0.0613P)2]
where P = (Fo2 + 2Fc2)/3
3001 reflections(Δ/σ)max < 0.001
175 parametersΔρmax = 0.22 e Å3
0 restraintsΔρmin = 0.28 e Å3
Crystal data top
C13H16N4O2V = 1314.98 (12) Å3
Mr = 260.30Z = 4
Monoclinic, P21/cMo Kα radiation
a = 5.9581 (2) ŵ = 0.09 mm1
b = 18.3064 (11) ÅT = 120 K
c = 12.0776 (7) Å0.20 × 0.10 × 0.04 mm
β = 93.4150 (12)°
Data collection top
KappaCCD
diffractometer
3001 independent reflections
Absorption correction: multi-scan
(SORTAV; Blessing, 1995, 1997)
1700 reflections with I > 2σ(I)
Tmin = 0.977, Tmax = 0.996Rint = 0.071
14938 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0520 restraints
wR(F2) = 0.124H-atom parameters constrained
S = 0.96Δρmax = 0.22 e Å3
3001 reflectionsΔρmin = 0.28 e Å3
175 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.1283 (2)0.28405 (8)0.47981 (12)0.0220 (4)
N20.0010 (2)0.24448 (9)0.55116 (12)0.0230 (4)
C30.1270 (3)0.20118 (10)0.48495 (16)0.0224 (4)
C40.0870 (3)0.21303 (11)0.37242 (16)0.0249 (5)
C50.0753 (3)0.26618 (11)0.37125 (15)0.0237 (4)
N50.1812 (3)0.29677 (10)0.28533 (13)0.0306 (4)
C110.2811 (3)0.33687 (10)0.52501 (15)0.0216 (4)
C120.4827 (3)0.35070 (11)0.47563 (16)0.0243 (4)
C130.6273 (3)0.40335 (10)0.51985 (16)0.0252 (5)
C140.5694 (3)0.44051 (10)0.61374 (16)0.0233 (4)
N140.7185 (3)0.49841 (9)0.65867 (15)0.0299 (4)
O1410.8857 (2)0.51414 (8)0.60916 (13)0.0390 (4)
O1420.6673 (3)0.52972 (9)0.74362 (14)0.0451 (4)
C150.3728 (3)0.42629 (11)0.66465 (17)0.0267 (5)
C160.2286 (3)0.37361 (11)0.62040 (15)0.0236 (5)
C310.2820 (3)0.14534 (10)0.53212 (16)0.0252 (5)
C320.1497 (4)0.07485 (12)0.5542 (2)0.0397 (6)
C330.3742 (4)0.17272 (13)0.63963 (18)0.0373 (6)
C340.4792 (4)0.12980 (13)0.44822 (19)0.0408 (6)
H40.15810.18910.31000.030*
H5A0.11820.28430.22030.037*
H5B0.21770.34330.29100.037*
H120.52010.32400.41190.029*
H130.76410.41390.48650.030*
H150.33730.45240.72930.032*
H160.09380.36250.65510.028*
H32A0.09370.05680.48460.059*
H32B0.24800.03800.58480.059*
H32C0.02240.08450.60730.059*
H33A0.25010.17910.69580.056*
H33B0.48120.13700.66610.056*
H33C0.45050.21960.62610.056*
H34A0.55870.17550.42970.061*
H34B0.58280.09530.48050.061*
H34C0.42230.10870.38080.061*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0240 (8)0.0251 (10)0.0169 (8)0.0029 (7)0.0014 (6)0.0017 (7)
N20.0227 (8)0.0241 (10)0.0226 (9)0.0014 (7)0.0029 (6)0.0032 (7)
C30.0201 (10)0.0216 (11)0.0255 (11)0.0047 (8)0.0007 (8)0.0016 (9)
C40.0256 (10)0.0273 (12)0.0217 (11)0.0007 (8)0.0005 (8)0.0045 (9)
C50.0250 (10)0.0265 (12)0.0197 (10)0.0016 (8)0.0018 (7)0.0003 (9)
N50.0375 (10)0.0350 (11)0.0192 (9)0.0100 (8)0.0019 (7)0.0014 (8)
C110.0231 (10)0.0215 (11)0.0199 (10)0.0009 (8)0.0020 (7)0.0017 (8)
C120.0243 (10)0.0248 (12)0.0238 (10)0.0029 (8)0.0017 (8)0.0000 (9)
C130.0216 (10)0.0248 (12)0.0292 (12)0.0021 (8)0.0012 (8)0.0037 (9)
C140.0245 (10)0.0187 (11)0.0259 (11)0.0007 (8)0.0052 (8)0.0017 (9)
N140.0292 (10)0.0244 (10)0.0354 (11)0.0018 (7)0.0046 (8)0.0023 (8)
O1410.0293 (8)0.0360 (10)0.0518 (10)0.0064 (7)0.0038 (7)0.0028 (8)
O1420.0492 (10)0.0425 (11)0.0436 (10)0.0092 (8)0.0036 (7)0.0178 (9)
C150.0289 (11)0.0267 (12)0.0242 (11)0.0039 (9)0.0011 (8)0.0027 (9)
C160.0228 (10)0.0254 (12)0.0228 (11)0.0021 (8)0.0020 (7)0.0023 (9)
C310.0264 (11)0.0219 (11)0.0276 (11)0.0012 (8)0.0037 (8)0.0008 (9)
C320.0395 (13)0.0270 (13)0.0534 (15)0.0045 (10)0.0097 (10)0.0070 (11)
C330.0372 (12)0.0377 (14)0.0385 (13)0.0059 (10)0.0140 (10)0.0021 (11)
C340.0332 (12)0.0425 (15)0.0464 (15)0.0121 (10)0.0008 (10)0.0031 (12)
Geometric parameters (Å, º) top
N1—N21.393 (2)C14—N141.466 (2)
N2—C31.327 (2)N14—O1411.226 (2)
C3—C41.411 (3)N14—O1421.229 (2)
C4—C51.373 (3)C15—C161.378 (3)
C5—N11.370 (2)C15—H150.95
N1—C111.415 (2)C16—H160.95
C3—C311.512 (3)C31—C331.524 (3)
C4—H40.95C31—C321.527 (3)
C5—N51.366 (2)C31—C341.532 (3)
N5—H5A0.88C32—H32A0.98
N5—H5B0.88C32—H32B0.98
C11—C161.386 (3)C32—H32C0.98
C11—C121.396 (3)C33—H33A0.98
C12—C131.379 (3)C33—H33B0.98
C12—H120.95C33—H33C0.98
C13—C141.384 (3)C34—H34A0.98
C13—H130.95C34—H34B0.98
C14—C151.380 (3)C34—H34C0.98
C5—N1—N2111.32 (14)C16—C15—C14119.04 (18)
C5—N1—C11129.70 (16)C16—C15—H15120.5
N2—N1—C11118.91 (14)C14—C15—H15120.5
C3—N2—N1104.59 (15)C15—C16—C11119.71 (18)
N2—C3—C4111.52 (17)C15—C16—H16120.1
N2—C3—C31120.89 (17)C11—C16—H16120.1
C4—C3—C31127.54 (17)C3—C31—C33110.97 (17)
C5—C4—C3106.18 (16)C3—C31—C32108.45 (15)
C5—C4—H4126.9C33—C31—C32109.74 (17)
C3—C4—H4126.9C3—C31—C34109.75 (16)
N5—C5—N1122.59 (17)C33—C31—C34108.88 (17)
N5—C5—C4130.99 (18)C32—C31—C34109.03 (18)
N1—C5—C4106.37 (16)C31—C32—H32A109.5
C5—N5—H5A112.3C31—C32—H32B109.5
C5—N5—H5B117.4H32A—C32—H32B109.5
H5A—N5—H5B114.2C31—C32—H32C109.5
C16—C11—C12120.66 (18)H32A—C32—H32C109.5
C16—C11—N1118.72 (17)H32B—C32—H32C109.5
C12—C11—N1120.61 (17)C31—C33—H33A109.5
C13—C12—C11119.68 (18)C31—C33—H33B109.5
C13—C12—H12120.2H33A—C33—H33B109.5
C11—C12—H12120.2C31—C33—H33C109.5
C12—C13—C14118.71 (18)H33A—C33—H33C109.5
C12—C13—H13120.6H33B—C33—H33C109.5
C14—C13—H13120.6C31—C34—H34A109.5
C15—C14—C13122.16 (18)C31—C34—H34B109.5
C15—C14—N14118.89 (18)H34A—C34—H34B109.5
C13—C14—N14118.92 (17)C31—C34—H34C109.5
O141—N14—O142123.13 (17)H34A—C34—H34C109.5
O141—N14—C14118.76 (17)H34B—C34—H34C109.5
O142—N14—C14118.10 (17)
C5—N1—N2—C31.83 (19)C11—C12—C13—C141.0 (3)
C11—N1—N2—C3179.06 (15)C12—C13—C14—C150.4 (3)
N1—N2—C3—C41.56 (19)C12—C13—C14—N14177.76 (16)
N1—N2—C3—C31175.96 (15)C15—C14—N14—O141175.34 (17)
N2—C3—C4—C50.8 (2)C13—C14—N14—O1412.8 (3)
C31—C3—C4—C5176.55 (17)C15—C14—N14—O1423.5 (3)
N2—N1—C5—N5179.03 (17)C13—C14—N14—O142178.3 (2)
C11—N1—C5—N54.1 (3)C13—C14—C15—C160.3 (3)
N2—N1—C5—C41.4 (2)N14—C14—C15—C16177.82 (17)
C11—N1—C5—C4178.24 (17)C14—C15—C16—C111.1 (3)
C3—C4—C5—N5177.8 (2)C12—C11—C16—C152.5 (3)
C3—C4—C5—N10.4 (2)N1—C11—C16—C15178.74 (16)
C5—N1—C11—C16145.19 (19)N2—C3—C31—C3332.8 (2)
N2—N1—C11—C1631.5 (2)C4—C3—C31—C33150.16 (19)
N2—N1—C11—C12147.35 (17)N2—C3—C31—C3287.9 (2)
C5—N1—C11—C1236.0 (3)C4—C3—C31—C3289.2 (2)
C16—C11—C12—C132.4 (3)N2—C3—C31—C34153.14 (18)
N1—C11—C12—C13178.82 (16)C4—C3—C31—C3429.8 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N5—H5A···N2i0.882.193.063 (2)173
N5—H5B···O142ii0.882.473.326 (2)166
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC13H16N4O2
Mr260.30
Crystal system, space groupMonoclinic, P21/c
Temperature (K)120
a, b, c (Å)5.9581 (2), 18.3064 (11), 12.0776 (7)
β (°) 93.4150 (12)
V3)1314.98 (12)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.20 × 0.10 × 0.04
Data collection
DiffractometerKappaCCD
diffractometer
Absorption correctionMulti-scan
(SORTAV; Blessing, 1995, 1997)
Tmin, Tmax0.977, 0.996
No. of measured, independent and
observed [I > 2σ(I)] reflections
14938, 3001, 1700
Rint0.071
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.052, 0.124, 0.96
No. of reflections3001
No. of parameters175
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.22, 0.28

Computer programs: KappaCCD Server Software (Nonius, 1997), DENZO–SMN (Otwinowski & Minor, 1997), DENZO–SMN, OSCAIL (McArdle, 2003) and SHELXS97 (Sheldrick, 1997), PLATON (Spek, 2003), SHELXL97 (Sheldrick, 1997) and PRPKAPPA (Ferguson, 1999).

Selected geometric parameters (Å, º) top
N1—N21.393 (2)N1—C111.415 (2)
N2—C31.327 (2)C5—N51.366 (2)
C3—C41.411 (3)C14—N141.466 (2)
C4—C51.373 (3)N14—O1411.226 (2)
C5—N11.370 (2)N14—O1421.229 (2)
N2—N1—C11—C12147.35 (17)C13—C14—N14—O1412.8 (3)
C5—N1—C11—C1236.0 (3)C13—C14—N14—O142178.3 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N5—H5A···N2i0.882.193.063 (2)173
N5—H5B···O142ii0.882.473.326 (2)166
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x+1, y+1, z+1.
 

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