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(E)-3-Amino-4-(2-phenyl­hydrazinyl­­idene)-1H-pyrazol-5(4H)-one

aChemistry Department, Faculty of Science, Helwan University, Cairo, Egypt, and bInstitut für Anorganische und Analytische Chemie, Technische Universität Braunschweig, Postfach 3329, D-38023 Braunschweig, Germany
*Correspondence e-mail: elgemeie@yahoo.com

(Received 7 December 2012; accepted 14 December 2012; online 4 January 2013)

The mol­ecule of the title compound, C9H9N5O, is essentially planar (r.m.s. deviation of all atoms = 0.02 Å) except for the NH2 H atoms. An intra­molecular hydrazinyl­idene–carbonyl N—H⋯O=C hydrogen bond is present. In the crystal, mol­ecules are connected via N—H⋯N/O hydrogen bonds, forming thick layers parallel to (100).

Related literature

The synthesis, chemistry and biological/medical activity of related compounds is described in: Elgemeie (2003[Elgemeie, G. H. (2003). Curr. Pharm. Des. 9, 2627-2642.]); Elgemeie & El-Aziz (2002[Elgemeie, G. H. & El-Aziz, H. A. (2002). Synth. Commun. 32, 253-261.]); Elgemeie & Sood (2003[Elgemeie, G. H. & Sood, S. A. (2003). Synth. Commun. 33, 2095-2105.], 2006[Elgemeie, G. H. & Sood, S. A. (2006). Synth. Commun. 36, 743-753.]); Elgemeie et al. (2001[Elgemeie, G. H., El-Ezbawy, S. R. & El-Aziz, H. A. (2001). Synth. Commun. 31, 3453-3451.], 2007[Elgemeie, G. H., Elghandour, A. H. & Abd Elaziz, G. W. (2007). Synth. Commun. 37, 2827-2834.], 2008[Elgemeie, G. H., Zaghary, W. A., Amin, K. M. & Nasr, T. M. (2008). J. Carbohydr. Chem. 27, 345-355.], 2009[Elgemeie, G. H., Zaghary, W. A., Amin, K. A. & Nasr, T. M. (2009). J. Carbohydr. Chem. 28, 161-170.]).

[Scheme 1]

Experimental

Crystal data
  • C9H9N5O

  • Mr = 203.21

  • Monoclinic, P 21 /c

  • a = 6.7380 (2) Å

  • b = 13.4310 (4) Å

  • c = 10.4563 (3) Å

  • β = 103.094 (3)°

  • V = 921.67 (5) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 0.86 mm−1

  • T = 100 K

  • 0.15 × 0.10 × 0.03 mm

Data collection
  • Oxford Diffraction Xcalibur (Atlas, Nova) diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, England.]) Tmin = 0.668, Tmax = 1.000

  • 26682 measured reflections

  • 1914 independent reflections

  • 1807 reflections with I > 2σ(I)

  • Rint = 0.029

Refinement
  • R[F2 > 2σ(F2)] = 0.032

  • wR(F2) = 0.087

  • S = 1.05

  • 1914 reflections

  • 152 parameters

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

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.26 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H01⋯O1i 0.909 (16) 1.949 (16) 2.8521 (11) 172.0 (14)
N3—H03B⋯N2ii 0.934 (17) 2.424 (16) 3.2711 (12) 150.8 (13)
N3—H03A⋯O1iii 0.908 (16) 2.141 (15) 2.9635 (11) 150.2 (13)
N5—H05⋯O1 0.897 (16) 2.174 (16) 2.8575 (11) 132.5 (13)
Symmetry codes: (i) -x, -y+1, -z; (ii) [x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (iii) [-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: CrysAlis PRO (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis PRO. Oxford Diffraction Ltd, Yarnton, 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: XP in SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Chemically synthesized purine analogues find numerous applications in clinical medicine and medical research (Elgemeie, 2003; Elgemeie et al., 2008). The pharmacological approach involves analogues in which the heterocyclic ring system has been modified so as to induce toxic effects when the analogue is incorporated into specific cell constituents (Elgemeie & El-Aziz, 2002). As part of our program directed towards the synthesis of purines and other antimetabolites (Elgemeie et al., 2001, 2009), we have recently reported various successful approaches to the syntheses of purine analogues. Derivatives of these ring systems are of interest as antimetabolites in biochemical reactions (Elgemeie & Sood, 2003). We have described several novel syntheses of functionalized pyrazoles (Elgemeie et al., 2007). These compounds are considered important intermediates for the synthesis of various purine ring systems (Elgemeie & Sood, 2006). As a continuation of this work, the title pyrazole compound (2), was prepared as a precursor for the synthesis of other purines. 2-Hydrazinyl-2-oxo-N-phenylacetohydrazonoyl cyanide (1) undergoes intramolecular cyclization by refluxing in ethanol containing catalytic amounts of piperidine to give the novel pyrazole derivative (2). The title compound can potentially exist in two other tautomeric forms with hydroxyl groups, (3) and (4). Spectral studies, however, indicated the presence of the ketonic tautomer (2) in solution (e.g. the 13C NMR signal at δ = 174.00, indicating a carbonyl carbon rather than C—OH.

The X-ray analysis of (2) (Fig. 1) establishes the exclusive presence of the keto tautomer in the solid state; all H atoms could be located unambiguously and bond lengths are also consistent with the keto form. The entire molecule is planar (r.m.s. deviation of all non-C atoms: 0.02 Å), except for the H atoms of the NH2 group; H03A lies 0.36 (2) and H03B 0.27 (2) Å outside the plane. Consistent with the E configuration, an intramolecular hydrogen bond N5—H05···O1 is observed.

The molecules are connected by hydrogen bonds #1–#3 to form thick hydrogen-bonded layers parallel to (100); the individual molecules are to a good approximation oriented in the planes (042) (Figs. 2, 3). Hydrogen bond #4 is the second and appreciably less linear branch of a three-centre interaction.

Related literature top

The synthesis, chemistry and biological/medical activity of related compounds is described in: Elgemeie (2003); Elgemeie & El-Aziz (2002); Elgemeie & Sood (2003, 2006); Elgemeie et al. (2001, 2007, 2008, 2009).

Experimental top

The title compound was obtained by refluxing an ethanolic solution of 2-hydrazinyl-2-oxo-N-phenylacetohydrazonoyl cyanide containing a few drops of piperidine for 1 h. After cooling, the precipitate was filtered off and recrystallized from ethanol. Yield (85%); m.p. 245 °C; IR (KBr) ν = 3450, 3350, 3300 (NH2, NH), 1660 (CO, s) cm-1; 1H NMR (DMSO) δ = 6.88 (s, br, 2H, NH2), 7.23 (s, br, 1H, NH), 7.41–7.92 (m, 5H, C6H5); MS, m/z = 203; Calc. for C9H9N5O: C, 53.19; H, 4.46; N, 34.46; O, 7.87. Found: C, 53.56; H, 4.57; N, 34.62; O, 7.61%.

Refinement top

The NH H atoms were refined freely. Other H atoms were placed in calculated positions and refined using a riding model with C—Harom 0.95 Å; the hydrogen U values were fixed at 1.2 × U(eq) of the parent atom.

Computing details top

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

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound. Ellipsoids represent 50% probability levels.
[Figure 2] Fig. 2. Packing diagram of the title compound projected along the b axis, showing the layer structure side-on.
[Figure 3] Fig. 3. Packing diagram of the title compound, viewed perpendicular to (100). Thick dashed bonds represent classical H bonds. Atom names correspond to the asymmetric unit; hydrogen bonds are numbered according to the Table on page Sup-7 (#4, the weaker part of a three-centre interaction, is omitted, as is the intramolecular interaction #5).
[Figure 4] Fig. 4. The formation of the title compound
(E)-3-Amino-4-(2-phenylhydrazinylidene)-1H- pyrazol-5(4H)-one top
Crystal data top
C9H9N5OF(000) = 424
Mr = 203.21Dx = 1.464 Mg m3
Monoclinic, P21/cMelting point: 518 K
Hall symbol: -P 2ybcCu Kα radiation, λ = 1.54184 Å
a = 6.7380 (2) ÅCell parameters from 18413 reflections
b = 13.4310 (4) Åθ = 3.3–75.6°
c = 10.4563 (3) ŵ = 0.86 mm1
β = 103.094 (3)°T = 100 K
V = 921.67 (5) Å3Tablet, orange-brown
Z = 40.15 × 0.10 × 0.03 mm
Data collection top
Oxford Diffraction Xcalibur (Atlas, Nova)
diffractometer
1914 independent reflections
Radiation source: Nova (Cu) X-ray Source1807 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.029
Detector resolution: 10.3543 pixels mm-1θmax = 75.8°, θmin = 5.5°
ω–scanh = 88
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
k = 1616
Tmin = 0.668, Tmax = 1.000l = 1313
26682 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)] = 0.032Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.087H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.0473P)2 + 0.2869P]
where P = (Fo2 + 2Fc2)/3
1914 reflections(Δ/σ)max < 0.001
152 parametersΔρmax = 0.17 e Å3
0 restraintsΔρmin = 0.26 e Å3
Crystal data top
C9H9N5OV = 921.67 (5) Å3
Mr = 203.21Z = 4
Monoclinic, P21/cCu Kα radiation
a = 6.7380 (2) ŵ = 0.86 mm1
b = 13.4310 (4) ÅT = 100 K
c = 10.4563 (3) Å0.15 × 0.10 × 0.03 mm
β = 103.094 (3)°
Data collection top
Oxford Diffraction Xcalibur (Atlas, Nova)
diffractometer
1914 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
1807 reflections with I > 2σ(I)
Tmin = 0.668, Tmax = 1.000Rint = 0.029
26682 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0320 restraints
wR(F2) = 0.087H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.17 e Å3
1914 reflectionsΔρmin = 0.26 e Å3
152 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.

Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)

- 6.7047 (0.0004) x + 0.5009 (0.0024) y + 3.2946 (0.0013) z = 0.2057 (0.0017)

* -0.0265 (0.0007) O1 * -0.0015 (0.0008) N1 * 0.0248 (0.0008) N2 * 0.0064 (0.0007) N3 * -0.0035 (0.0008) N4 * 0.0047 (0.0008) N5 * 0.0127 (0.0009) C3 * -0.0173 (0.0009) C4 * -0.0155 (0.0009) C5 * 0.0096 (0.0009) C11 * 0.0334 (0.0009) C12 * 0.0207 (0.0009) C13 * -0.0104 (0.0009) C14 * -0.0239 (0.0009) C15 * -0.0136 (0.0009) C16 0.3618 (0.0145) H03A 0.2676 (0.0152) H03B

Rms deviation of fitted atoms = 0.0175

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
O10.09284 (11)0.44649 (5)0.17545 (7)0.02234 (19)
N10.06030 (14)0.60858 (6)0.09217 (8)0.0210 (2)
H010.008 (2)0.5972 (11)0.0053 (16)0.036 (4)*
N20.08679 (13)0.70841 (6)0.13887 (8)0.0210 (2)
C30.15061 (15)0.70044 (7)0.26628 (10)0.0188 (2)
C40.16773 (15)0.59729 (7)0.30772 (10)0.0182 (2)
C50.10365 (15)0.53946 (8)0.18664 (9)0.0190 (2)
N30.19896 (14)0.77858 (7)0.35089 (9)0.0230 (2)
H03B0.202 (2)0.7633 (12)0.4385 (16)0.041 (4)*
H03A0.135 (2)0.8364 (12)0.3206 (15)0.036 (4)*
N40.22316 (12)0.56774 (6)0.42917 (8)0.0180 (2)
N50.22648 (13)0.47167 (6)0.45303 (8)0.0193 (2)
H050.189 (2)0.4280 (12)0.3870 (15)0.034 (4)*
C110.28700 (14)0.43692 (8)0.58298 (10)0.0190 (2)
C120.28637 (16)0.33470 (8)0.60446 (11)0.0229 (2)
H120.24420.29010.53290.028*
C130.34813 (16)0.29858 (8)0.73178 (11)0.0268 (3)
H130.34870.22890.74730.032*
C140.40897 (16)0.36360 (9)0.83626 (11)0.0283 (3)
H140.45160.33860.92320.034*
C150.40732 (17)0.46548 (9)0.81331 (10)0.0271 (3)
H150.44840.50990.88510.033*
C160.34645 (16)0.50330 (8)0.68682 (10)0.0223 (2)
H160.34540.57300.67150.027*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0293 (4)0.0182 (4)0.0181 (4)0.0032 (3)0.0024 (3)0.0003 (3)
N10.0273 (5)0.0194 (4)0.0149 (4)0.0021 (3)0.0018 (3)0.0002 (3)
N20.0249 (4)0.0182 (4)0.0193 (4)0.0005 (3)0.0038 (3)0.0006 (3)
C30.0188 (5)0.0190 (5)0.0189 (5)0.0015 (4)0.0045 (4)0.0008 (4)
C40.0188 (5)0.0189 (5)0.0166 (5)0.0006 (4)0.0036 (4)0.0002 (4)
C50.0199 (5)0.0205 (5)0.0164 (5)0.0012 (4)0.0038 (4)0.0008 (4)
N30.0310 (5)0.0173 (4)0.0199 (4)0.0032 (4)0.0042 (4)0.0004 (3)
N40.0190 (4)0.0179 (4)0.0172 (4)0.0019 (3)0.0042 (3)0.0012 (3)
N50.0237 (4)0.0178 (4)0.0155 (4)0.0001 (3)0.0028 (3)0.0002 (3)
C110.0170 (4)0.0228 (5)0.0170 (5)0.0015 (4)0.0039 (4)0.0034 (4)
C120.0216 (5)0.0225 (5)0.0246 (5)0.0002 (4)0.0049 (4)0.0016 (4)
C130.0229 (5)0.0262 (6)0.0316 (6)0.0021 (4)0.0071 (4)0.0107 (4)
C140.0239 (5)0.0384 (7)0.0220 (5)0.0025 (5)0.0040 (4)0.0111 (5)
C150.0272 (5)0.0360 (6)0.0175 (5)0.0002 (5)0.0034 (4)0.0008 (4)
C160.0238 (5)0.0242 (5)0.0188 (5)0.0006 (4)0.0045 (4)0.0010 (4)
Geometric parameters (Å, º) top
O1—C51.2548 (13)C13—C141.3861 (17)
N1—C51.3387 (13)C14—C151.3890 (17)
N1—N21.4242 (12)C15—C161.3891 (15)
N2—C31.3083 (13)N1—H010.909 (16)
C3—N31.3637 (13)N3—H03B0.934 (17)
C3—C41.4484 (13)N3—H03A0.908 (16)
C4—N41.3019 (13)N5—H050.897 (16)
C4—C51.4645 (13)C12—H120.9500
N4—N51.3134 (12)C13—H130.9500
N5—C111.4069 (13)C14—H140.9500
C11—C121.3914 (15)C15—H150.9500
C11—C161.3918 (15)C16—H160.9500
C12—C131.3892 (15)
C5—N1—N2114.23 (8)C14—C15—C16120.92 (10)
C3—N2—N1105.00 (8)C15—C16—C11118.64 (10)
N2—C3—N3124.94 (9)C5—N1—H01126.2 (10)
N2—C3—C4111.62 (9)N2—N1—H01119.4 (10)
N3—C3—C4123.43 (9)C3—N3—H03B114.5 (10)
N4—C4—C3124.69 (9)C3—N3—H03A114.0 (9)
N4—C4—C5130.16 (9)H03B—N3—H03A115.7 (14)
C3—C4—C5105.11 (8)N4—N5—H05120.4 (10)
O1—C5—N1128.54 (9)C11—N5—H05119.7 (10)
O1—C5—C4127.43 (9)C13—C12—H12120.4
N1—C5—C4104.03 (9)C11—C12—H12120.4
C4—N4—N5118.26 (9)C14—C13—H13119.8
N4—N5—C11119.87 (8)C12—C13—H13119.8
C12—C11—C16121.13 (9)C13—C14—H14120.2
C12—C11—N5118.19 (9)C15—C14—H14120.2
C16—C11—N5120.67 (9)C14—C15—H15119.5
C13—C12—C11119.21 (10)C16—C15—H15119.5
C14—C13—C12120.42 (10)C15—C16—H16120.7
C13—C14—C15119.68 (10)C11—C16—H16120.7
C5—N1—N2—C30.65 (12)C3—C4—N4—N5178.06 (9)
N1—N2—C3—N3178.81 (9)C5—C4—N4—N50.52 (16)
N1—N2—C3—C40.17 (11)C4—N4—N5—C11179.53 (9)
N2—C3—C4—N4178.34 (9)N4—N5—C11—C12179.30 (8)
N3—C3—C4—N42.66 (16)N4—N5—C11—C160.93 (14)
N2—C3—C4—C50.29 (12)C16—C11—C12—C130.62 (15)
N3—C3—C4—C5179.29 (9)N5—C11—C12—C13179.15 (9)
N2—N1—C5—O1179.27 (9)C11—C12—C13—C140.23 (16)
N2—N1—C5—C40.81 (11)C12—C13—C14—C150.24 (16)
N4—C4—C5—O11.54 (18)C13—C14—C15—C160.33 (17)
C3—C4—C5—O1179.44 (10)C14—C15—C16—C110.05 (16)
N4—C4—C5—N1178.55 (10)C12—C11—C16—C150.53 (15)
C3—C4—C5—N10.65 (10)N5—C11—C16—C15179.24 (9)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H01···O1i0.909 (16)1.949 (16)2.8521 (11)172.0 (14)
N3—H03B···N2ii0.934 (17)2.424 (16)3.2711 (12)150.8 (13)
N3—H03A···O1iii0.908 (16)2.141 (15)2.9635 (11)150.2 (13)
N3—H03B···N1ii0.934 (17)2.674 (16)3.2562 (13)121.1 (12)
N5—H05···O10.897 (16)2.174 (16)2.8575 (11)132.5 (13)
Symmetry codes: (i) x, y+1, z; (ii) x, y+3/2, z+1/2; (iii) x, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC9H9N5O
Mr203.21
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)6.7380 (2), 13.4310 (4), 10.4563 (3)
β (°) 103.094 (3)
V3)921.67 (5)
Z4
Radiation typeCu Kα
µ (mm1)0.86
Crystal size (mm)0.15 × 0.10 × 0.03
Data collection
DiffractometerOxford Diffraction Xcalibur (Atlas, Nova)
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
Tmin, Tmax0.668, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
26682, 1914, 1807
Rint0.029
(sin θ/λ)max1)0.629
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.032, 0.087, 1.05
No. of reflections1914
No. of parameters152
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.17, 0.26

Computer programs: CrysAlis PRO (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H01···O1i0.909 (16)1.949 (16)2.8521 (11)172.0 (14)
N3—H03B···N2ii0.934 (17)2.424 (16)3.2711 (12)150.8 (13)
N3—H03A···O1iii0.908 (16)2.141 (15)2.9635 (11)150.2 (13)
N3—H03B···N1ii0.934 (17)2.674 (16)3.2562 (13)121.1 (12)
N5—H05···O10.897 (16)2.174 (16)2.8575 (11)132.5 (13)
Symmetry codes: (i) x, y+1, z; (ii) x, y+3/2, z+1/2; (iii) x, y+1/2, z+1/2.
 

References

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