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Acta Crystallogr Sect E Struct Rep Online. 2010 October 1; 66(Pt 10): o2505.
Published online 2010 September 4. doi:  10.1107/S1600536810033970
PMCID: PMC2983223

1-{5-[4-(Hex­yloxy)phen­yl]-3-phenyl-4,5-dihydro-1H-pyrazol-1-yl}ethanone

Abstract

The crystal structure of the title compound, C23H28N2O2, is composed of discrete mol­ecules with bond lengths and angles quite typical for pyrazoline derivatives of this class. The plane containing the pyrazoline unit is nearly planar with the mean plane of the phenyl ring at the 3-position, making a dihedral angle of 1.96 (3)°. The crystal packing is stabilized by weak C—H(...)π inter­actions involving both of the aromatic rings.

Related literature

For the biological activity and pharmacological properties of 2-pyrazoline derivatives, see: Cottineau et al. (2002 [triangle]); Dhal et al. (1975 [triangle]); Regaila et al. (1979 [triangle]); Rathish et al. (2009 [triangle]); Subbaramaiah et al. (2002 [triangle]); Manna et al. (2002 [triangle]). For the syntheses and crystal structures of 2-pyrazoline derivatives, see: Bai et al. (2009 [triangle]); Lu et al. (2008 [triangle]); Fahrni et al. (2003 [triangle]); Jian et al. (2008 [triangle]).

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Object name is e-66-o2505-scheme1.jpg

Experimental

Crystal data

  • C23H28N2O2
  • M r = 364.47
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o2505-efi1.jpg
  • a = 5.3937 (8) Å
  • b = 20.237 (3) Å
  • c = 18.163 (3) Å
  • β = 95.144 (2)°
  • V = 1974.6 (5) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.08 mm−1
  • T = 100 K
  • 0.3 × 0.2 × 0.18 mm

Data collection

  • Bruker APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.675, T max = 0.746
  • 18731 measured reflections
  • 4517 independent reflections
  • 3430 reflections with I > 2σ(I)
  • R int = 0.042

Refinement

  • R[F 2 > 2σ(F 2)] = 0.041
  • wR(F 2) = 0.103
  • S = 1.03
  • 4517 reflections
  • 246 parameters
  • H-atom parameters constrained
  • Δρmax = 0.28 e Å−3
  • Δρmin = −0.21 e Å−3

Data collection: APEX2 (Bruker, 2008 [triangle]); cell refinement: SAINT (Bruker, 2008 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]); software used to prepare material for publication: publCIF (Westrip, 2010 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810033970/zq2055sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810033970/zq2055Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

AA is grateful to the HEC-Pakistan for financial support for his PhD program under scholarship No. [IIC–0317109].

supplementary crystallographic information

Comment

Pyrazoline systems are well known nitrogen-containing heterocyclic compounds which exhibit a wide range of biological activities and pharmacological properties such as anti-hyperglycemic (Cottineau et al., 2002), antifungal (Dhal et al., 1975), anti-diabetic, anaesthetic and analgesic properties (Regaila et al., 1979), anti-inflammation (Rathish et al., 2009), anticancer (Subbaramaiah et al., 2002), and monoamine oxidases inhibitors (Manna et al., 2002).

The molecular structure of the title compound is shown in Fig. 1. The asymmetric unit consists of discrete [PhCOCH3C6H4C3H3N2O(CH2)5CH3] entities, devoid of any classical hydrogen bonds. All bond lengths and angles are in the normal range (Bai et al., 2009; Lu et al., 2008). In the pyrazolinyl ring, the C—N and C=N bond lengths of 1.4753 (17) and 1.2856 (17) are comparable with those in similar structures [C—N 1.482 (2)–1.515 (9) Å, C=N 1.291 (2)–1.300 (10) Å] (Fahrni et al., 2003). The N—N bond length of 1.3853 (15) is longer than in the structure of Jian et al. [N–N 1.373 (2)–1.380 (8) Å]. The plane containing the pyrazoline moiety is nearly planar with the mean plane of the phenyl ring C16–C21 making a dihedral angle of 1.96 (3)°.

The crystal packing is stabilized by weak C-H···π interactions involving both of the phenyl rings.

Experimental

A mixture of (E)-3-(4-(hexyloxy)phenyl)-1-phenylprop-2-en-1-one (3.08 g, 10 mmol) and hydrazine hydrate (1.0 g, 20 mmol) was taken in acetic acid (25 ml), and two drops of concentrated hydrochloric acid were added. The mixture was refluxed for 6 h. The precipitated solids were filtered, dried and recrystallized from ethanol. The single crystals were obtained from a mixture of ethyl acetate and dichloromethane by slow evaporation.

Refinement

All hydrogen atoms were placed in calculated positions as riding on their parent carbon atoms with C–H = 0.93 to 0.97 Å and with Uiso(H) set to 1.2 or 1.5 times Ueq(C).

Figures

Fig. 1.
Molecular structure of (I) showing atom numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.

Crystal data

C23H28N2O2F(000) = 784
Mr = 364.47Dx = 1.226 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3895 reflections
a = 5.3937 (8) Åθ = 2.3–28.1°
b = 20.237 (3) ŵ = 0.08 mm1
c = 18.163 (3) ÅT = 100 K
β = 95.144 (2)°Block, white
V = 1974.6 (5) Å30.3 × 0.2 × 0.18 mm
Z = 4

Data collection

Bruker APEXII CCD area-detector diffractometer4517 independent reflections
Radiation source: fine-focus sealed tube3430 reflections with I > 2σ(I)
graphiteRint = 0.042
ω scansθmax = 27.5°, θmin = 1.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −7→6
Tmin = 0.675, Tmax = 0.746k = −25→26
18731 measured reflectionsl = −23→23

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.041Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.103H-atom parameters constrained
S = 1.03w = 1/[σ2(Fo2) + (0.0466P)2 + 0.4272P] where P = (Fo2 + 2Fc2)/3
4517 reflections(Δ/σ)max < 0.001
246 parametersΔρmax = 0.28 e Å3
0 restraintsΔρmin = −0.21 e Å3

Special details

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.
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)

xyzUiso*/Ueq
O10.18742 (16)0.45980 (5)−0.05993 (5)0.0179 (2)
O20.32678 (19)0.17097 (5)0.05044 (5)0.0271 (2)
N10.1119 (2)0.20218 (6)0.14456 (6)0.0191 (3)
N2−0.0638 (2)0.18796 (6)0.19341 (6)0.0179 (2)
C10.5550 (4)0.54544 (9)−0.39381 (9)0.0418 (4)
H1A0.40640.5562−0.42450.063*
H1B0.67000.5234−0.42290.063*
H1C0.62970.5852−0.37340.063*
C20.4902 (3)0.50039 (7)−0.33153 (7)0.0249 (3)
H2A0.64190.4891−0.30140.030*
H2B0.41950.4598−0.35260.030*
C30.3071 (3)0.53097 (7)−0.28225 (7)0.0249 (3)
H3A0.37740.5716−0.26130.030*
H3B0.15510.5421−0.31230.030*
C40.2433 (3)0.48570 (7)−0.21971 (7)0.0225 (3)
H4A0.39430.4769−0.18810.027*
H4B0.18450.4439−0.24080.027*
C50.0473 (3)0.51279 (7)−0.17220 (7)0.0209 (3)
H5A0.11000.5529−0.14800.025*
H5B−0.10100.5241−0.20390.025*
C6−0.0217 (2)0.46428 (7)−0.11418 (7)0.0187 (3)
H6A−0.16750.4796−0.09160.022*
H6B−0.05840.4214−0.13630.022*
C70.1846 (2)0.41158 (6)−0.00717 (6)0.0151 (3)
C8−0.0066 (2)0.36643 (7)−0.00220 (7)0.0165 (3)
H8−0.14870.3685−0.03510.020*
C90.0156 (2)0.31812 (7)0.05236 (7)0.0167 (3)
H9−0.11320.28800.05580.020*
C100.2267 (2)0.31401 (6)0.10170 (6)0.0152 (3)
C110.4149 (2)0.36037 (7)0.09649 (7)0.0168 (3)
H110.55620.35860.12980.020*
C120.3957 (2)0.40882 (7)0.04292 (7)0.0165 (3)
H120.52300.43950.04020.020*
C130.2542 (2)0.26318 (7)0.16271 (7)0.0173 (3)
H130.43060.25240.17420.021*
C140.1407 (2)0.28567 (7)0.23384 (7)0.0174 (3)
H14A0.26580.28710.27560.021*
H14B0.06340.32880.22740.021*
C15−0.0501 (2)0.23286 (7)0.24369 (7)0.0160 (3)
C16−0.2154 (2)0.23144 (7)0.30378 (7)0.0163 (3)
C17−0.3931 (2)0.18129 (7)0.30687 (7)0.0177 (3)
H17−0.40520.14820.27120.021*
C18−0.5505 (2)0.18075 (7)0.36271 (7)0.0194 (3)
H18−0.66790.14730.36440.023*
C19−0.5348 (2)0.22987 (7)0.41648 (7)0.0193 (3)
H19−0.64200.22950.45380.023*
C21−0.1990 (2)0.28018 (7)0.35816 (7)0.0193 (3)
H21−0.08060.31350.35710.023*
C20−0.3591 (3)0.27924 (7)0.41409 (7)0.0199 (3)
H20−0.34780.31210.45010.024*
C220.1542 (3)0.16031 (7)0.08809 (7)0.0209 (3)
C23−0.0247 (3)0.10362 (7)0.07542 (8)0.0259 (3)
H23A0.01720.07840.03350.039*
H23B−0.19110.12040.06620.039*
H23C−0.01450.07580.11840.039*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0188 (5)0.0165 (5)0.0177 (4)−0.0025 (4)−0.0017 (3)0.0030 (4)
O20.0332 (6)0.0255 (6)0.0248 (5)0.0035 (5)0.0155 (4)0.0011 (4)
N10.0223 (6)0.0178 (6)0.0185 (5)−0.0017 (5)0.0093 (4)0.0004 (4)
N20.0189 (6)0.0197 (6)0.0160 (5)0.0009 (5)0.0067 (4)0.0018 (4)
C10.0560 (12)0.0388 (11)0.0334 (8)0.0093 (9)0.0187 (8)0.0104 (8)
C20.0299 (8)0.0235 (8)0.0209 (7)−0.0010 (6)0.0005 (6)0.0014 (6)
C30.0329 (8)0.0212 (8)0.0205 (6)−0.0001 (6)0.0010 (6)0.0028 (6)
C40.0271 (8)0.0209 (8)0.0194 (6)0.0007 (6)0.0005 (5)0.0018 (5)
C50.0247 (7)0.0179 (7)0.0191 (6)0.0021 (6)−0.0026 (5)0.0009 (5)
C60.0179 (7)0.0187 (7)0.0187 (6)0.0010 (5)−0.0024 (5)−0.0003 (5)
C70.0168 (6)0.0146 (7)0.0145 (6)0.0021 (5)0.0038 (5)−0.0007 (5)
C80.0138 (6)0.0193 (7)0.0163 (6)0.0009 (5)0.0021 (5)−0.0024 (5)
C90.0147 (6)0.0187 (7)0.0175 (6)−0.0023 (5)0.0060 (5)−0.0016 (5)
C100.0163 (6)0.0156 (7)0.0145 (6)0.0012 (5)0.0061 (5)−0.0005 (5)
C110.0145 (6)0.0217 (7)0.0144 (6)0.0013 (5)0.0023 (5)−0.0015 (5)
C120.0142 (6)0.0179 (7)0.0179 (6)−0.0027 (5)0.0041 (5)−0.0012 (5)
C130.0167 (7)0.0189 (7)0.0168 (6)0.0010 (5)0.0040 (5)0.0015 (5)
C140.0186 (7)0.0184 (7)0.0156 (6)−0.0004 (5)0.0041 (5)0.0017 (5)
C150.0155 (6)0.0169 (7)0.0159 (6)0.0022 (5)0.0017 (5)0.0028 (5)
C160.0158 (6)0.0190 (7)0.0144 (6)0.0026 (5)0.0022 (5)0.0031 (5)
C170.0188 (7)0.0178 (7)0.0165 (6)0.0014 (5)0.0012 (5)−0.0006 (5)
C180.0190 (7)0.0207 (7)0.0190 (6)−0.0014 (6)0.0036 (5)0.0035 (5)
C190.0185 (7)0.0240 (8)0.0160 (6)0.0039 (6)0.0057 (5)0.0042 (5)
C210.0191 (7)0.0188 (7)0.0201 (6)−0.0018 (6)0.0026 (5)0.0013 (5)
C200.0241 (7)0.0205 (7)0.0154 (6)0.0021 (6)0.0038 (5)−0.0006 (5)
C220.0270 (8)0.0194 (8)0.0172 (6)0.0053 (6)0.0066 (5)0.0024 (5)
C230.0345 (8)0.0225 (8)0.0214 (7)0.0005 (6)0.0066 (6)−0.0027 (6)

Geometric parameters (Å, °)

O1—C71.3688 (15)C9—C101.3867 (17)
O1—C61.4325 (14)C9—H90.9300
O2—C221.2226 (17)C10—C111.3918 (18)
N1—C221.3652 (17)C10—C131.5094 (17)
N1—N21.3853 (15)C11—C121.3786 (18)
N1—C131.4753 (17)C11—H110.9300
N2—C151.2856 (17)C12—H120.9300
C1—C21.518 (2)C13—C141.5471 (17)
C1—H1A0.9600C13—H130.9800
C1—H1B0.9600C14—C151.5054 (18)
C1—H1C0.9600C14—H14A0.9700
C2—C31.523 (2)C14—H14B0.9700
C2—H2A0.9700C15—C161.4701 (17)
C2—H2B0.9700C16—C211.3932 (18)
C3—C41.5225 (19)C16—C171.4008 (19)
C3—H3A0.9700C17—C181.3795 (18)
C3—H3B0.9700C17—H170.9300
C4—C51.525 (2)C18—C191.3906 (19)
C4—H4A0.9700C18—H180.9300
C4—H4B0.9700C19—C201.380 (2)
C5—C61.5109 (19)C19—H190.9300
C5—H5A0.9700C21—C201.3912 (18)
C5—H5B0.9700C21—H210.9300
C6—H6A0.9700C20—H200.9300
C6—H6B0.9700C22—C231.504 (2)
C7—C81.3868 (18)C23—H23A0.9600
C7—C121.3934 (17)C23—H23B0.9600
C8—C91.3896 (18)C23—H23C0.9600
C8—H80.9300
C7—O1—C6117.98 (10)C9—C10—C13122.44 (12)
C22—N1—N2121.49 (11)C11—C10—C13119.01 (11)
C22—N1—C13124.64 (11)C12—C11—C10121.22 (12)
N2—N1—C13113.75 (10)C12—C11—H11119.4
C15—N2—N1108.01 (11)C10—C11—H11119.4
C2—C1—H1A109.5C11—C12—C7119.64 (12)
C2—C1—H1B109.5C11—C12—H12120.2
H1A—C1—H1B109.5C7—C12—H12120.2
C2—C1—H1C109.5N1—C13—C10113.03 (10)
H1A—C1—H1C109.5N1—C13—C14101.29 (10)
H1B—C1—H1C109.5C10—C13—C14113.09 (11)
C1—C2—C3113.51 (13)N1—C13—H13109.7
C1—C2—H2A108.9C10—C13—H13109.7
C3—C2—H2A108.9C14—C13—H13109.7
C1—C2—H2B108.9C15—C14—C13102.50 (10)
C3—C2—H2B108.9C15—C14—H14A111.3
H2A—C2—H2B107.7C13—C14—H14A111.3
C4—C3—C2113.33 (12)C15—C14—H14B111.3
C4—C3—H3A108.9C13—C14—H14B111.3
C2—C3—H3A108.9H14A—C14—H14B109.2
C4—C3—H3B108.9N2—C15—C16120.89 (12)
C2—C3—H3B108.9N2—C15—C14114.44 (11)
H3A—C3—H3B107.7C16—C15—C14124.65 (11)
C3—C4—C5114.86 (12)C21—C16—C17118.99 (12)
C3—C4—H4A108.6C21—C16—C15120.56 (12)
C5—C4—H4A108.6C17—C16—C15120.45 (12)
C3—C4—H4B108.6C18—C17—C16120.23 (12)
C5—C4—H4B108.6C18—C17—H17119.9
H4A—C4—H4B107.5C16—C17—H17119.9
C6—C5—C4112.80 (12)C17—C18—C19120.54 (13)
C6—C5—H5A109.0C17—C18—H18119.7
C4—C5—H5A109.0C19—C18—H18119.7
C6—C5—H5B109.0C20—C19—C18119.61 (12)
C4—C5—H5B109.0C20—C19—H19120.2
H5A—C5—H5B107.8C18—C19—H19120.2
O1—C6—C5107.04 (10)C20—C21—C16120.27 (13)
O1—C6—H6A110.3C20—C21—H21119.9
C5—C6—H6A110.3C16—C21—H21119.9
O1—C6—H6B110.3C19—C20—C21120.37 (13)
C5—C6—H6B110.3C19—C20—H20119.8
H6A—C6—H6B108.6C21—C20—H20119.8
O1—C7—C8124.77 (11)O2—C22—N1119.85 (13)
O1—C7—C12115.21 (11)O2—C22—C23124.01 (12)
C8—C7—C12120.00 (12)N1—C22—C23116.12 (12)
C7—C8—C9119.52 (12)C22—C23—H23A109.5
C7—C8—H8120.2C22—C23—H23B109.5
C9—C8—H8120.2H23A—C23—H23B109.5
C10—C9—C8121.11 (12)C22—C23—H23C109.5
C10—C9—H9119.4H23A—C23—H23C109.5
C8—C9—H9119.4H23B—C23—H23C109.5
C9—C10—C11118.49 (12)
C22—N1—N2—C15175.04 (12)C9—C10—C13—C14−86.17 (15)
C13—N1—N2—C15−1.30 (14)C11—C10—C13—C1491.00 (14)
C1—C2—C3—C4−179.80 (13)N1—C13—C14—C15−0.22 (12)
C2—C3—C4—C5−176.14 (12)C10—C13—C14—C15121.03 (11)
C3—C4—C5—C6176.22 (11)N1—N2—C15—C16179.74 (11)
C7—O1—C6—C5−170.59 (10)N1—N2—C15—C141.13 (15)
C4—C5—C6—O170.78 (14)C13—C14—C15—N2−0.55 (14)
C6—O1—C7—C8−0.01 (18)C13—C14—C15—C16−179.10 (11)
C6—O1—C7—C12178.57 (11)N2—C15—C16—C21179.85 (12)
O1—C7—C8—C9177.70 (12)C14—C15—C16—C21−1.68 (19)
C12—C7—C8—C9−0.81 (19)N2—C15—C16—C17−0.64 (18)
C7—C8—C9—C10−0.41 (19)C14—C15—C16—C17177.82 (12)
C8—C9—C10—C111.34 (19)C21—C16—C17—C180.53 (19)
C8—C9—C10—C13178.52 (12)C15—C16—C17—C18−178.98 (12)
C9—C10—C11—C12−1.08 (19)C16—C17—C18—C190.04 (19)
C13—C10—C11—C12−178.36 (12)C17—C18—C19—C20−0.43 (19)
C10—C11—C12—C7−0.12 (19)C17—C16—C21—C20−0.71 (19)
O1—C7—C12—C11−177.58 (11)C15—C16—C21—C20178.80 (12)
C8—C7—C12—C111.07 (19)C18—C19—C20—C210.2 (2)
C22—N1—C13—C1063.40 (16)C16—C21—C20—C190.3 (2)
N2—N1—C13—C10−120.39 (12)N2—N1—C22—O2−172.82 (12)
C22—N1—C13—C14−175.30 (12)C13—N1—C22—O23.1 (2)
N2—N1—C13—C140.90 (13)N2—N1—C22—C238.60 (18)
C9—C10—C13—N128.19 (17)C13—N1—C22—C23−175.47 (12)
C11—C10—C13—N1−154.64 (11)

Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the C7–C12 and C16–C21 aromatic rings, respectively.
D—H···AD—HH···AD···AD—H···A
C8—H8···Cg2i0.932.953.6252 (15)131
C14—H14A···Cg2ii0.972.633.5024 (14)151
C19—H19···Cg1iii0.932.713.4299 (15)135

Symmetry codes: (i) x, −y−1/2, z−3/2; (ii) x+1, y, z; (iii) x−1, −y−1/2, z−1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: ZQ2055).

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