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

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ISSN: 2056-9890

(Z)-4-[2-(2,4-Di­methyl­phen­yl)hydrazinyl­­idene]-3-methyl­pyrazol-5(1H)-one

aDepartment of Chemistry, P. A. College of Engineering, Mangalore 574 153, India, bDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri 574 199, India, cDepartment of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India, dDepartment of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA, and eDepartment of Chemistry, Howard University, 525 College Street NW, Washington, DC 20059, USA
*Correspondence e-mail: jjasinski@keene.edu

(Received 4 March 2013; accepted 8 March 2013; online 13 March 2013)

The mol­ecule of the title compound, C12H14N4O, is roughly planar, with a dihedral angle of 8.0 (8)° between the benzene and pyrazole rings, and an intra­molecular N—H⋯O hydrogen bond forms an S(6) ring motif. In the crystal, mol­ecules are linked into an inversion dimer by a pair of N—H⋯O hydrogen bonds, which form an R22(8) ring motif.

Related literature

For the biological activity of pyrazolo­nes, see: Amir & Kumar (2005[Amir, M. & Kumar, S. (2005). Indian. J. Chem. Sect. B, 44, 2532-2537.]); Rao et al. (2008[Rao, B. S., Akberali, P. M., Holla, B. S. & Sarojini, B. K. (2008). J. Pharmacol. Toxicol. 3, 102-103.]); Samshuddin et al. (2011[Samshuddin, S., Narayana, B., Sarojini, B. K., Khan, M. T. H., Yathirajan, H. S., Darshan Raj, C. G. & Raghavendra, R. (2011). Med. Chem. Res. 21, 2012-2022.]). For the radical scavenging capacity of pyrazol-5-ols, see: Sarojini et al. (2010[Sarojini, B. K., Vidyagayatri, M., Darshan Raj, C. G., Barath, B. R. & Manjunatha, H. (2010). Lett. Drug Des. Discov. 7, 214-224.]). For related structures, see: Butcher et al. (2011[Butcher, R. J., Akkurt, M., Samshuddin, S., Narayana, B. & Yathirajan, H. S. (2011). Acta Cryst. E67, o1019.]); Samshuddin et al. (2011[Samshuddin, S., Narayana, B., Sarojini, B. K., Khan, M. T. H., Yathirajan, H. S., Darshan Raj, C. G. & Raghavendra, R. (2011). Med. Chem. Res. 21, 2012-2022.]). For reference 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.]).

[Scheme 1]

Experimental

Crystal data
  • C12H14N4O

  • Mr = 230.27

  • Monoclinic, P 21 /c

  • a = 5.2926 (2) Å

  • b = 22.1675 (6) Å

  • c = 10.0529 (3) Å

  • β = 101.770 (3)°

  • V = 1154.64 (6) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 0.72 mm−1

  • T = 123 K

  • 0.51 × 0.24 × 0.08 mm

Data collection
  • Agilent Xcalibur (Ruby, Gemini) diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012[Agilent (2012). CrysAlis PRO and CrysAlis RED. Agilent Technologies, Yarnton, Oxfordshire, England.]) Tmin = 0.538, Tmax = 0.944

  • 4152 measured reflections

  • 2328 independent reflections

  • 2061 reflections with I > 2σ(I)

  • Rint = 0.024

Refinement
  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.124

  • S = 1.05

  • 2328 reflections

  • 157 parameters

  • H-atom parameters constrained

  • Δρmax = 0.34 e Å−3

  • Δρmin = −0.27 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2A⋯O1i 0.88 1.95 2.8233 (15) 172
N4—H4D⋯O1 0.88 2.00 2.7286 (15) 139
Symmetry code: (i) -x, -y+1, -z+2.

Data collection: CrysAlis PRO (Agilent, 2012[Agilent (2012). CrysAlis PRO and CrysAlis RED. Agilent Technologies, Yarnton, Oxfordshire, England.]); cell refinement: CrysAlis PRO ; data reduction: CrysAlis RED (Agilent, 2012[Agilent (2012). CrysAlis PRO and CrysAlis RED. Agilent Technologies, Yarnton, Oxfordshire, England.]); 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: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

In view of high medicinal value such as anti-inflammatory, analgesic (Amir & Kumar, 2005), antimicrobial (Samshuddin et al., 2011) and antiproliferative activity (Rao et al. 2008) of pyrazolones, it was thought worthwhile to synthesize compounds based on pyrazolone derivatives. In addition, the radical scavenging capacity and molecular binding of various derivatives of pyrazol-5-ols were reported (Sarojini et al., 2010). Also, the crystal structures of some of the related pyrazoles viz. 3,5-bis(4-bromophenyl)-1-phenyl-4,5-dihydro-1H-pyrazole (Samshuddin et al., 2011) and 5-bis(4-methylphenyl)-1-phenyl-4,5-dihydro-1H-pyrazole (Butcher et al., 2011) have been reported. In view of the importance of pyrazolones, we report herein the crystal structure of the title compound, C12H14N4O, (I).

The asymmetric unit of (I) consists of a 3-methyl-1H-pyrazol-5(4H)-one group bonded to 2,4-(dimethylphenyl)hydrazone in a nearly planar conformation (Fig. 1). The mean plane of the benzene ring is twisted by 8.0 (8)° from that of the pyrazole ring. Bond lengths are in normal ranges (Allen et al., 1987). In the crystal, intermolecular N2—H2A···O1 hydrogen bonds (Table 1) which form R22(8) ring motifs linking the molecule into dimers are observed (Fig. 2). An intramolecular N4—H4D···O1 hydrogen bond is also present.

Related literature top

For the biological activity of pyrazolones, see: Amir & Kumar (2005); Rao et al. (2008); Samshuddin et al. (2011). For the radical scavenging capacity of pyrazol-5-ols, see: Sarojini et al. (2010). For related structures, see: Butcher et al. (2011); Samshuddin et al. (2011). For reference bond-length data, see: Allen et al. (1987).

Experimental top

Ethyl 2-[2-(2,4-dimethylphenyl)hydrazinylidene]-3-oxobutanoate (2.62 g, 0.01 mol) and hydrazine hydrate (0.75 ml, 0.015 mol) were refluxed in acetic acid for 4–6 h. Then the reaction mixture was cooled to room temperature and the solid product was filtered off. Single crystals were grown by slow evaporation from a mixture of petroleum ether and ethyl acetate (1:3 v/v) (m.p. 421–423 K).

Refinement top

All of the H atoms were placed in their calculated positions and then refined using the riding model with Atom—H lengths of 0.95 Å (CH), 0.98 Å (CH3) or 0.88 Å (NH). Isotropic displacement parameters for these atoms were set to 1.2 (CH, NH) or 1.5 (CH3) times Ueq of the parent atom.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis RED (Agilent, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound showing the atom labeling scheme and 30% probability displacement ellipsoids.
[Figure 2] Fig. 2. Packing diagram of the title compound viewed along the b axis. Dashed lines indicate intermolecular N—H···O hydrogen bonds which form R22(8) ring motifs linking the molecule into dimers. H atoms not involved in hydrogen bonding have been removed for clarity.
(Z)-4-[2-(2,4-Dimethylphenyl)hydrazinylidene]-3-methylpyrazol-5(1H)-one top
Crystal data top
C12H14N4OF(000) = 488
Mr = 230.27Dx = 1.325 Mg m3
Monoclinic, P21/cCu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2ybcCell parameters from 2088 reflections
a = 5.2926 (2) Åθ = 4.0–75.3°
b = 22.1675 (6) ŵ = 0.72 mm1
c = 10.0529 (3) ÅT = 123 K
β = 101.770 (3)°Long plate, colourless
V = 1154.64 (6) Å30.51 × 0.24 × 0.08 mm
Z = 4
Data collection top
Agilent Xcalibur (Ruby, Gemini)
diffractometer
2328 independent reflections
Radiation source: Enhance (Cu) X-ray Source2061 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
Detector resolution: 10.5081 pixels mm-1θmax = 75.5°, θmin = 4.0°
ω scansh = 56
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2012)
k = 2726
Tmin = 0.538, Tmax = 0.944l = 1112
4152 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)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.124H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0699P)2 + 0.3531P]
where P = (Fo2 + 2Fc2)/3
2328 reflections(Δ/σ)max < 0.001
157 parametersΔρmax = 0.34 e Å3
0 restraintsΔρmin = 0.27 e Å3
Crystal data top
C12H14N4OV = 1154.64 (6) Å3
Mr = 230.27Z = 4
Monoclinic, P21/cCu Kα radiation
a = 5.2926 (2) ŵ = 0.72 mm1
b = 22.1675 (6) ÅT = 123 K
c = 10.0529 (3) Å0.51 × 0.24 × 0.08 mm
β = 101.770 (3)°
Data collection top
Agilent Xcalibur (Ruby, Gemini)
diffractometer
2328 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2012)
2061 reflections with I > 2σ(I)
Tmin = 0.538, Tmax = 0.944Rint = 0.024
4152 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.124H-atom parameters constrained
S = 1.05Δρmax = 0.34 e Å3
2328 reflectionsΔρmin = 0.27 e Å3
157 parameters
Special details top

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 > 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
O10.18460 (18)0.45530 (5)0.89208 (10)0.0213 (2)
N10.2909 (2)0.61180 (5)0.90296 (12)0.0212 (3)
N20.1729 (2)0.55870 (5)0.93665 (12)0.0206 (3)
H2A0.05900.55810.98930.025*
N30.5733 (2)0.50000 (5)0.73044 (12)0.0190 (3)
N40.5362 (2)0.44146 (5)0.73009 (12)0.0196 (3)
H4D0.42650.42660.77660.024*
C10.2517 (3)0.50879 (6)0.88022 (14)0.0183 (3)
C20.4380 (3)0.53140 (6)0.80200 (14)0.0186 (3)
C30.4473 (3)0.59579 (6)0.82398 (14)0.0196 (3)
C40.6109 (3)0.63998 (6)0.76933 (16)0.0242 (3)
H4A0.60070.67930.81260.036*
H4B0.54970.64380.67090.036*
H4C0.79030.62600.78850.036*
C50.6657 (3)0.40171 (6)0.65796 (14)0.0187 (3)
C60.6331 (3)0.33981 (6)0.67717 (14)0.0190 (3)
C70.7561 (3)0.29989 (6)0.60384 (14)0.0202 (3)
H7A0.73380.25780.61450.024*
C80.9106 (3)0.31954 (7)0.51552 (14)0.0208 (3)
C90.9423 (3)0.38169 (7)0.50101 (15)0.0226 (3)
H9A1.04930.39600.44250.027*
C100.8203 (3)0.42275 (6)0.57057 (14)0.0216 (3)
H10A0.84160.46480.55900.026*
C110.4740 (3)0.31736 (6)0.77591 (15)0.0229 (3)
H11A0.29520.33100.74650.034*
H11B0.54520.33330.86670.034*
H11C0.47830.27320.77850.034*
C121.0424 (3)0.27468 (7)0.43960 (16)0.0259 (3)
H12A0.98830.23370.45780.039*
H12B1.22990.27830.46980.039*
H12C0.99460.28290.34190.039*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0210 (5)0.0191 (5)0.0251 (5)0.0010 (4)0.0078 (4)0.0011 (4)
N10.0195 (6)0.0181 (6)0.0257 (6)0.0016 (4)0.0038 (5)0.0009 (5)
N20.0192 (6)0.0197 (6)0.0246 (6)0.0005 (4)0.0081 (5)0.0002 (4)
N30.0184 (5)0.0176 (6)0.0204 (6)0.0011 (4)0.0024 (4)0.0006 (4)
N40.0190 (5)0.0182 (6)0.0226 (6)0.0010 (4)0.0068 (4)0.0005 (4)
C10.0155 (6)0.0201 (7)0.0188 (6)0.0016 (5)0.0021 (5)0.0004 (5)
C20.0168 (6)0.0190 (6)0.0193 (6)0.0003 (5)0.0023 (5)0.0022 (5)
C30.0176 (6)0.0185 (6)0.0214 (6)0.0034 (5)0.0012 (5)0.0014 (5)
C40.0228 (7)0.0182 (6)0.0320 (8)0.0026 (5)0.0066 (6)0.0036 (6)
C50.0163 (6)0.0203 (7)0.0190 (6)0.0006 (5)0.0023 (5)0.0024 (5)
C60.0161 (6)0.0209 (7)0.0190 (6)0.0023 (5)0.0015 (5)0.0010 (5)
C70.0184 (6)0.0183 (7)0.0224 (7)0.0018 (5)0.0005 (5)0.0023 (5)
C80.0156 (6)0.0242 (7)0.0213 (6)0.0004 (5)0.0010 (5)0.0043 (5)
C90.0199 (6)0.0269 (7)0.0223 (7)0.0018 (6)0.0073 (5)0.0003 (6)
C100.0228 (7)0.0187 (6)0.0233 (7)0.0010 (5)0.0049 (5)0.0002 (5)
C110.0257 (7)0.0190 (6)0.0255 (7)0.0037 (5)0.0085 (6)0.0016 (5)
C120.0223 (7)0.0256 (7)0.0309 (7)0.0011 (6)0.0079 (6)0.0080 (6)
Geometric parameters (Å, º) top
O1—C11.2504 (17)C5—C61.4013 (19)
N1—C31.3075 (19)C6—C71.395 (2)
N1—N21.4059 (16)C6—C111.5112 (18)
N2—C11.3475 (18)C7—C81.394 (2)
N2—H2A0.8800C7—H7A0.9500
N3—N41.3125 (16)C8—C91.399 (2)
N3—C21.3135 (18)C8—C121.5084 (19)
N4—C51.4052 (18)C9—C101.385 (2)
N4—H4D0.8800C9—H9A0.9500
C1—C21.4692 (18)C10—H10A0.9500
C2—C31.4437 (19)C11—H11A0.9800
C3—C41.4850 (19)C11—H11B0.9800
C4—H4A0.9800C11—H11C0.9800
C4—H4B0.9800C12—H12A0.9800
C4—H4C0.9800C12—H12B0.9800
C5—C101.397 (2)C12—H12C0.9800
C3—N1—N2106.63 (11)C7—C6—C11121.39 (13)
C1—N2—N1113.29 (12)C5—C6—C11120.92 (12)
C1—N2—H2A123.4C8—C7—C6122.40 (13)
N1—N2—H2A123.4C8—C7—H7A118.8
N4—N3—C2115.29 (12)C6—C7—H7A118.8
N3—N4—C5122.19 (12)C7—C8—C9118.22 (13)
N3—N4—H4D118.9C7—C8—C12120.53 (13)
C5—N4—H4D118.9C9—C8—C12121.24 (13)
O1—C1—N2128.34 (13)C10—C9—C8121.07 (13)
O1—C1—C2127.52 (12)C10—C9—H9A119.5
N2—C1—C2104.13 (12)C8—C9—H9A119.5
N3—C2—C3127.04 (13)C9—C10—C5119.43 (13)
N3—C2—C1127.81 (12)C9—C10—H10A120.3
C3—C2—C1105.13 (12)C5—C10—H10A120.3
N1—C3—C2110.81 (12)C6—C11—H11A109.5
N1—C3—C4122.32 (13)C6—C11—H11B109.5
C2—C3—C4126.86 (13)H11A—C11—H11B109.5
C3—C4—H4A109.5C6—C11—H11C109.5
C3—C4—H4B109.5H11A—C11—H11C109.5
H4A—C4—H4B109.5H11B—C11—H11C109.5
C3—C4—H4C109.5C8—C12—H12A109.5
H4A—C4—H4C109.5C8—C12—H12B109.5
H4B—C4—H4C109.5H12A—C12—H12B109.5
C10—C5—C6121.18 (13)C8—C12—H12C109.5
C10—C5—N4121.68 (13)H12A—C12—H12C109.5
C6—C5—N4117.14 (12)H12B—C12—H12C109.5
C7—C6—C5117.68 (13)
C3—N1—N2—C10.01 (15)N3—N4—C5—C107.1 (2)
C2—N3—N4—C5179.75 (12)N3—N4—C5—C6172.99 (12)
N1—N2—C1—O1179.22 (13)C10—C5—C6—C71.3 (2)
N1—N2—C1—C20.17 (15)N4—C5—C6—C7178.63 (11)
N4—N3—C2—C3177.63 (12)C10—C5—C6—C11177.61 (12)
N4—N3—C2—C10.2 (2)N4—C5—C6—C112.45 (19)
O1—C1—C2—N30.9 (2)C5—C6—C7—C81.0 (2)
N2—C1—C2—N3178.50 (13)C11—C6—C7—C8177.90 (12)
O1—C1—C2—C3179.13 (13)C6—C7—C8—C90.2 (2)
N2—C1—C2—C30.28 (14)C6—C7—C8—C12179.27 (12)
N2—N1—C3—C20.20 (15)C7—C8—C9—C101.1 (2)
N2—N1—C3—C4178.85 (12)C12—C8—C9—C10179.80 (13)
N3—C2—C3—N1178.55 (13)C8—C9—C10—C50.8 (2)
C1—C2—C3—N10.30 (15)C6—C5—C10—C90.4 (2)
N3—C2—C3—C40.5 (2)N4—C5—C10—C9179.51 (12)
C1—C2—C3—C4178.70 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···O1i0.881.952.8233 (15)172
N4—H4D···O10.882.002.7286 (15)139
Symmetry code: (i) x, y+1, z+2.

Experimental details

Crystal data
Chemical formulaC12H14N4O
Mr230.27
Crystal system, space groupMonoclinic, P21/c
Temperature (K)123
a, b, c (Å)5.2926 (2), 22.1675 (6), 10.0529 (3)
β (°) 101.770 (3)
V3)1154.64 (6)
Z4
Radiation typeCu Kα
µ (mm1)0.72
Crystal size (mm)0.51 × 0.24 × 0.08
Data collection
DiffractometerAgilent Xcalibur (Ruby, Gemini)
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Agilent, 2012)
Tmin, Tmax0.538, 0.944
No. of measured, independent and
observed [I > 2σ(I)] reflections
4152, 2328, 2061
Rint0.024
(sin θ/λ)max1)0.628
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.124, 1.05
No. of reflections2328
No. of parameters157
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.34, 0.27

Computer programs: CrysAlis PRO (Agilent, 2012), CrysAlis RED (Agilent, 2012), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···O1i0.881.952.8233 (15)172
N4—H4D···O10.882.002.7286 (15)139
Symmetry code: (i) x, y+1, z+2.
 

Acknowledgements

BKS gratefully acknowledges the Department of Atomic Energy (DAE)/BRNS, Government of India, for providing financial assistance in the BRNS Project (No. 2011/34/20-BRNS/0846). RJB acknowledges the NSF–MRI program (grant No. CHE-0619278) for funds to purchase the X-ray diffractometer.

References

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First citationAmir, M. & Kumar, S. (2005). Indian. J. Chem. Sect. B, 44, 2532–2537.
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First citationSamshuddin, S., Narayana, B., Sarojini, B. K., Khan, M. T. H., Yathirajan, H. S., Darshan Raj, C. G. & Raghavendra, R. (2011). Med. Chem. Res. 21, 2012–2022.  Web of Science CSD CrossRef
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First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals

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