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

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ISSN: 2056-9890

4-[2-(4-Chloro­phen­yl)hydrazinyl­­idene]-3-methyl-1H-pyrazol-5(4H)-one

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri, Mangalore 574 199, India
*Correspondence e-mail: hkfun@usm.my

(Received 12 September 2011; accepted 12 September 2011; online 17 September 2011)

In the title compound, C10H9ClN4O, the pyrazole ring [maximum deviation = 0.014 (2) Å] forms a dihedral angle of 7.06 (14)° with the chloro­benzene ring. The mol­ecular conformation is stabilized by an intra­molecular N—H⋯O hydrogen bond, which generates an S(6) ring motif. In the crystal, inversion dimers linked by pairs of C—H⋯O hydrogen bonds generate R22(16) ring motifs. The dimers are further connected by N—H⋯N hydrogen bonds, thereby forming layers lying parallel to the bc plane.

Related literature

For general background to and applications of pyrazole derivatives, see: Rai & Kalluraya (2006[Rai, N. S. & Kalluraya, B. (2006). Indian J. Chem. Sect. B, 46, 375-378.]); Rai et al. (2008[Rai, N. S., Kalluraya, B., Lingappa, B., Shenoy, S. & Puranic, V. G. (2008). Eur. J. Med. Chem. 43, 1715-1720.]); Sridhar & Perumal (2003[Sridhar, R. & Perumal, P. T. (2003). Synth. Commun. 33, 1483-1488.]). For standard bond-length data, see: Allen et al. (1987[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.]). For graph-set notation, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chamg, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.]).

[Scheme 1]

Experimental

Crystal data
  • C10H9ClN4O

  • Mr = 236.66

  • Monoclinic, P 21 /c

  • a = 15.8496 (5) Å

  • b = 3.8184 (1) Å

  • c = 20.3794 (6) Å

  • β = 123.575 (2)°

  • V = 1027.59 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.35 mm−1

  • T = 100 K

  • 0.55 × 0.06 × 0.05 mm

Data collection
  • Bruker SMART APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.829, Tmax = 0.984

  • 11013 measured reflections

  • 3048 independent reflections

  • 2213 reflections with I > 2σ(I)

  • Rint = 0.050

Refinement
  • R[F2 > 2σ(F2)] = 0.063

  • wR(F2) = 0.135

  • S = 1.08

  • 3048 reflections

  • 154 parameters

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

  • Δρmax = 0.47 e Å−3

  • Δρmin = −0.49 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N1⋯O1 0.93 (3) 2.15 (3) 2.841 (3) 131 (3)
N3—H1N3⋯N4i 0.87 (3) 2.16 (3) 2.983 (3) 158 (3)
C5—H5A⋯O1ii 0.95 2.47 3.334 (3) 151
Symmetry codes: (i) [-x+2, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]; (ii) -x+2, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. 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 and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Pyrazole are nitrogen-containing heterocyclic compounds and various procedures have been developed for their synthesis (Rai & Kalluraya, 2006). The chemistry of pyrazole derivatives has been the subject of much interest due to their various applications and widespread potential and proven biological and pharmacological activities (Rai et al., 2008). Steroids containing a pyrazole moiety are of interest as psychopharmacological agents. Some alkyl- and aryl-substituted pyrazoles have a sharply pronounced sedative action on the central nervous system. Furthermore, certain alkyl pyrazoles show significant bacteriostatic, bacteriocidal, fungicidal, analgesic and anti-pyretic activities (Sridhar & Perumal, 2003).

In the title molecule, Fig. 1, the pyrazole ring (N3/N4/C7-C9, maximum deviation of 0.014 (2) Å at atom N3) forms a dihedral angle of 7.06 (14)° with the phenyl ring (C1-C6). Bond lengths (Allen et al., 1987) and angles are within normal ranges. The molecular structure is stabilized by an intramolecular N1–H1N1···O1 hydrogen bond, which generates an S(6) ring motif (Fig. 1, Bernstein et al., 1995).

In the crystal, Fig. 2, the intermolecular C5–H5A···O1 hydrogen bonds (Table 1) form the inversion dimers producing sixteen-membered ring motifs R22(16) (Bernstein et al., 1995). Another intermolecular N3–H1N3···N4 hydrogen bond connects these dimers to another molecule forming two-dimensional layers parallel to bc plane.

Related literature top

For general background to and applications of pyrazole derivatives, see: Rai & Kalluraya (2006); Rai et al. (2008); Sridhar & Perumal (2003). For standard bond-length data, see: Allen et al. (1987). For graph-set notation, see: Bernstein et al. (1995). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Experimental top

To a solution of ethyl-(2-[2-(4-chlorophenyl)hydrazinylidene]-3-oxobutanoate (0.01 mol) dissolved in glacial acetic acid (20 ml), a solution of hydrazine hydrate (0.02 mol) in glacial acetic acid (25 ml) was added and the mixture was refluxed for 4 h. It is cooled and allowed to stand overnight. The solid product that separated was filtered and dried. It was then recrystallized from ethanol. Yellow needles were obtained from 1:2 mixtures of DMF and ethanol by slow evaporation.

Refinement top

Atoms H1N1 and H3N3 were located from the difference Fourier map and refined freely [N–H = 0.87 (3) and 0.92 (3) Å]. The remaining H atoms were positioned geometrically and refined using a riding model with C–H = 0.95 or 0.98 Å and Uiso(H) = 1.2 or 1.5 Ueq(C). A rotating-group model was applied for the methyl group.

Structure description top

Pyrazole are nitrogen-containing heterocyclic compounds and various procedures have been developed for their synthesis (Rai & Kalluraya, 2006). The chemistry of pyrazole derivatives has been the subject of much interest due to their various applications and widespread potential and proven biological and pharmacological activities (Rai et al., 2008). Steroids containing a pyrazole moiety are of interest as psychopharmacological agents. Some alkyl- and aryl-substituted pyrazoles have a sharply pronounced sedative action on the central nervous system. Furthermore, certain alkyl pyrazoles show significant bacteriostatic, bacteriocidal, fungicidal, analgesic and anti-pyretic activities (Sridhar & Perumal, 2003).

In the title molecule, Fig. 1, the pyrazole ring (N3/N4/C7-C9, maximum deviation of 0.014 (2) Å at atom N3) forms a dihedral angle of 7.06 (14)° with the phenyl ring (C1-C6). Bond lengths (Allen et al., 1987) and angles are within normal ranges. The molecular structure is stabilized by an intramolecular N1–H1N1···O1 hydrogen bond, which generates an S(6) ring motif (Fig. 1, Bernstein et al., 1995).

In the crystal, Fig. 2, the intermolecular C5–H5A···O1 hydrogen bonds (Table 1) form the inversion dimers producing sixteen-membered ring motifs R22(16) (Bernstein et al., 1995). Another intermolecular N3–H1N3···N4 hydrogen bond connects these dimers to another molecule forming two-dimensional layers parallel to bc plane.

For general background to and applications of pyrazole derivatives, see: Rai & Kalluraya (2006); Rai et al. (2008); Sridhar & Perumal (2003). For standard bond-length data, see: Allen et al. (1987). For graph-set notation, see: Bernstein et al. (1995). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound showing 50% probability displacement ellipsoids for non-H atoms. The intramolecular hydrogen bond is shown as a dashed line.
[Figure 2] Fig. 2. The crystal structure of the title compound, viewed along the b axis. H atoms not involved in hydrogen bonds (dashed lines) have been omitted for clarity.
4-[2-(4-Chlorophenyl)hydrazinylidene]-3-methyl-1H- pyrazol-5(4H)-one top
Crystal data top
C10H9ClN4OF(000) = 488
Mr = 236.66Dx = 1.530 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3778 reflections
a = 15.8496 (5) Åθ = 3.5–30.2°
b = 3.8184 (1) ŵ = 0.35 mm1
c = 20.3794 (6) ÅT = 100 K
β = 123.575 (2)°Needle, yellow
V = 1027.59 (5) Å30.55 × 0.06 × 0.05 mm
Z = 4
Data collection top
Bruker SMART APEXII CCD
diffractometer
3048 independent reflections
Radiation source: fine-focus sealed tube2213 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.050
φ and ω scansθmax = 30.3°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 2222
Tmin = 0.829, Tmax = 0.984k = 55
11013 measured reflectionsl = 2828
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)] = 0.063Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.135H atoms treated by a mixture of independent and constrained refinement
S = 1.08 w = 1/[σ2(Fo2) + (0.0465P)2 + 1.3049P]
where P = (Fo2 + 2Fc2)/3
3048 reflections(Δ/σ)max = 0.001
154 parametersΔρmax = 0.47 e Å3
0 restraintsΔρmin = 0.49 e Å3
Crystal data top
C10H9ClN4OV = 1027.59 (5) Å3
Mr = 236.66Z = 4
Monoclinic, P21/cMo Kα radiation
a = 15.8496 (5) ŵ = 0.35 mm1
b = 3.8184 (1) ÅT = 100 K
c = 20.3794 (6) Å0.55 × 0.06 × 0.05 mm
β = 123.575 (2)°
Data collection top
Bruker SMART APEXII CCD
diffractometer
3048 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
2213 reflections with I > 2σ(I)
Tmin = 0.829, Tmax = 0.984Rint = 0.050
11013 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0630 restraints
wR(F2) = 0.135H atoms treated by a mixture of independent and constrained refinement
S = 1.08Δρmax = 0.47 e Å3
3048 reflectionsΔρmin = 0.49 e Å3
154 parameters
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
Cl10.53838 (4)0.43205 (18)0.09622 (3)0.01992 (17)
O11.00665 (12)0.1519 (5)0.58137 (9)0.0189 (4)
N10.81975 (15)0.0862 (6)0.43307 (10)0.0142 (4)
N20.78635 (14)0.0814 (6)0.47044 (11)0.0142 (4)
N30.98057 (15)0.1246 (6)0.67129 (11)0.0161 (4)
N40.90051 (14)0.2933 (6)0.66973 (11)0.0159 (4)
C10.65048 (16)0.0676 (7)0.31307 (13)0.0146 (5)
H1A0.62610.05180.34030.018*
C20.58548 (17)0.1447 (7)0.23340 (13)0.0155 (5)
H2A0.51660.07400.20540.019*
C30.62202 (17)0.3249 (7)0.19539 (12)0.0142 (5)
C40.72266 (17)0.4294 (7)0.23485 (13)0.0157 (5)
H4A0.74650.55510.20790.019*
C50.78795 (17)0.3479 (6)0.31411 (13)0.0140 (5)
H5A0.85710.41550.34180.017*
C60.75154 (17)0.1671 (6)0.35249 (12)0.0135 (5)
C70.85040 (16)0.1370 (6)0.54667 (12)0.0131 (5)
C80.95460 (17)0.0130 (6)0.59853 (12)0.0140 (5)
C90.82387 (17)0.3049 (7)0.59611 (13)0.0138 (5)
C100.72429 (17)0.4604 (7)0.57061 (14)0.0171 (5)
H10A0.73040.59040.61450.026*
H10B0.70270.62000.52640.026*
H10C0.67410.27350.55410.026*
H1N10.887 (2)0.154 (8)0.4584 (16)0.020 (7)*
H1N31.029 (2)0.044 (9)0.7166 (19)0.033 (9)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0212 (3)0.0260 (3)0.0096 (2)0.0014 (3)0.0067 (2)0.0042 (2)
O10.0180 (8)0.0234 (10)0.0183 (8)0.0028 (7)0.0120 (7)0.0005 (8)
N10.0153 (9)0.0189 (10)0.0096 (8)0.0012 (8)0.0075 (7)0.0008 (8)
N20.0189 (9)0.0149 (9)0.0122 (8)0.0010 (8)0.0107 (7)0.0007 (8)
N30.0148 (9)0.0236 (11)0.0100 (8)0.0009 (8)0.0070 (8)0.0018 (8)
N40.0182 (9)0.0203 (11)0.0130 (8)0.0026 (8)0.0110 (8)0.0009 (8)
C10.0163 (11)0.0162 (11)0.0143 (10)0.0002 (9)0.0104 (9)0.0008 (10)
C20.0163 (11)0.0170 (12)0.0144 (10)0.0000 (9)0.0093 (9)0.0021 (10)
C30.0179 (11)0.0164 (11)0.0068 (9)0.0034 (9)0.0059 (8)0.0001 (9)
C40.0223 (11)0.0152 (11)0.0141 (10)0.0007 (10)0.0129 (9)0.0011 (10)
C50.0156 (11)0.0142 (11)0.0138 (10)0.0005 (9)0.0091 (9)0.0026 (9)
C60.0185 (11)0.0137 (11)0.0096 (9)0.0017 (9)0.0085 (8)0.0013 (9)
C70.0135 (10)0.0164 (12)0.0106 (9)0.0009 (9)0.0075 (8)0.0012 (9)
C80.0160 (11)0.0159 (12)0.0120 (9)0.0015 (9)0.0088 (8)0.0019 (9)
C90.0184 (11)0.0132 (11)0.0136 (10)0.0026 (9)0.0111 (9)0.0013 (9)
C100.0201 (11)0.0171 (12)0.0182 (10)0.0006 (10)0.0131 (9)0.0017 (10)
Geometric parameters (Å, º) top
Cl1—C31.745 (2)C2—C31.380 (3)
O1—C81.232 (3)C2—H2A0.9500
N1—N21.310 (3)C3—C41.390 (3)
N1—C61.413 (3)C4—C51.389 (3)
N1—H1N10.92 (3)C4—H4A0.9500
N2—C71.321 (3)C5—C61.386 (3)
N3—C81.369 (3)C5—H5A0.9500
N3—N41.407 (3)C7—C91.439 (3)
N3—H1N30.87 (3)C7—C81.462 (3)
N4—C91.309 (3)C9—C101.486 (3)
C1—C61.390 (3)C10—H10A0.9800
C1—C21.391 (3)C10—H10B0.9800
C1—H1A0.9500C10—H10C0.9800
N2—N1—C6119.14 (19)C6—C5—H5A120.2
N2—N1—H1N1121.3 (17)C4—C5—H5A120.2
C6—N1—H1N1119.5 (17)C5—C6—C1121.1 (2)
N1—N2—C7117.88 (19)C5—C6—N1118.4 (2)
C8—N3—N4113.00 (18)C1—C6—N1120.6 (2)
C8—N3—H1N3127 (2)N2—C7—C9124.3 (2)
N4—N3—H1N3116 (2)N2—C7—C8128.6 (2)
C9—N4—N3107.15 (19)C9—C7—C8106.78 (18)
C6—C1—C2119.3 (2)O1—C8—N3128.2 (2)
C6—C1—H1A120.3O1—C8—C7128.8 (2)
C2—C1—H1A120.3N3—C8—C7102.99 (19)
C3—C2—C1119.4 (2)N4—C9—C7110.0 (2)
C3—C2—H2A120.3N4—C9—C10123.2 (2)
C1—C2—H2A120.3C7—C9—C10126.8 (2)
C2—C3—C4121.5 (2)C9—C10—H10A109.5
C2—C3—Cl1118.75 (17)C9—C10—H10B109.5
C4—C3—Cl1119.76 (18)H10A—C10—H10B109.5
C5—C4—C3119.2 (2)C9—C10—H10C109.5
C5—C4—H4A120.4H10A—C10—H10C109.5
C3—C4—H4A120.4H10B—C10—H10C109.5
C6—C5—C4119.5 (2)
C6—N1—N2—C7176.4 (2)N1—N2—C7—C9177.5 (2)
C8—N3—N4—C92.5 (3)N1—N2—C7—C85.1 (4)
C6—C1—C2—C31.4 (4)N4—N3—C8—O1177.3 (2)
C1—C2—C3—C40.4 (4)N4—N3—C8—C72.6 (3)
C1—C2—C3—Cl1177.90 (19)N2—C7—C8—O14.7 (4)
C2—C3—C4—C50.5 (4)C9—C7—C8—O1178.2 (2)
Cl1—C3—C4—C5178.85 (19)N2—C7—C8—N3175.2 (2)
C3—C4—C5—C60.6 (4)C9—C7—C8—N31.8 (3)
C4—C5—C6—C10.4 (4)N3—N4—C9—C71.2 (3)
C4—C5—C6—N1179.7 (2)N3—N4—C9—C10179.2 (2)
C2—C1—C6—C51.4 (4)N2—C7—C9—N4174.2 (2)
C2—C1—C6—N1178.8 (2)C8—C7—C9—N40.4 (3)
N2—N1—C6—C5179.3 (2)N2—C7—C9—C103.7 (4)
N2—N1—C6—C10.6 (3)C8—C7—C9—C10177.5 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N1···O10.93 (3)2.15 (3)2.841 (3)131 (3)
N3—H1N3···N4i0.87 (3)2.16 (3)2.983 (3)158 (3)
C5—H5A···O1ii0.952.473.334 (3)151
Symmetry codes: (i) x+2, y+1/2, z+3/2; (ii) x+2, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC10H9ClN4O
Mr236.66
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)15.8496 (5), 3.8184 (1), 20.3794 (6)
β (°) 123.575 (2)
V3)1027.59 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.35
Crystal size (mm)0.55 × 0.06 × 0.05
Data collection
DiffractometerBruker SMART APEXII CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.829, 0.984
No. of measured, independent and
observed [I > 2σ(I)] reflections
11013, 3048, 2213
Rint0.050
(sin θ/λ)max1)0.710
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.063, 0.135, 1.08
No. of reflections3048
No. of parameters154
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.47, 0.49

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N1···O10.93 (3)2.15 (3)2.841 (3)131 (3)
N3—H1N3···N4i0.87 (3)2.16 (3)2.983 (3)158 (3)
C5—H5A···O1ii0.952.473.334 (3)151
Symmetry codes: (i) x+2, y+1/2, z+3/2; (ii) x+2, y+1, z+1.
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009.

§Thomson Reuters ResearcherID: A-5525-2009.

Acknowledgements

HKF and CKQ thank Universiti Sains Malaysia for the Research University Grant (No. 1001/PFIZIK/811160).

References

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