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Acta Crystallogr Sect E Struct Rep Online. 2008 December 1; 64(Pt 12): o2363–o2364.
Published online 2008 November 13. doi:  10.1107/S1600536808037161
PMCID: PMC2959893

[3-(4-Chloro­phen­yl)-5-hydr­oxy-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl](3-pyrid­yl)methanone

Abstract

In the title compound, C21H16ClN3O2, the dihedral angles formed by the pyrazole ring with the pyridyl, phenyl­ene and phenyl rings are 6.80 (5), 9.23 (5) and 74.96 (5)°, respectively. The phenyl and phenyl­ene rings are inclined at 80.14 (2)°. Intra­molecular O—H(...)O and C—H(...)N hydrogen bonds generate S(6) ring motifs. The crystal packing is strengthened by short inter­molecular O—H(...)N, C—H(...)O hydrogen bonds and π–π stacking inter­actions with centroid–centroid distances of 3.6247 (5)–3.7205 (5) Å, together with inter­molecular short O(...)N contacts [2.7682 (11) Å]. Mol­ecules are linked into infinite chains along [100].

Related literature

For the biological applications of pyrazoles, see: Kalluraya & Ramesh (2001 [triangle]); Watanabe et al. (1998 [triangle]); Yuhong & Rajender (2005 [triangle]). For bond-length data, see: Allen et al. (1987 [triangle]). For graph-set analysis of hydrogen bonding, see: Bernstein et al. (1995 [triangle]).

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Object name is e-64-o2363-scheme1.jpg

Experimental

Crystal data

  • C21H16ClN3O2
  • M r = 377.82
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-o2363-efi1.jpg
  • a = 7.5916 (1) Å
  • b = 9.7644 (1) Å
  • c = 12.5474 (2) Å
  • α = 104.424 (1)°
  • β = 94.960 (1)°
  • γ = 96.081 (1)°
  • V = 889.55 (2) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.24 mm−1
  • T = 100.0 (1) K
  • 0.47 × 0.29 × 0.19 mm

Data collection

  • Bruker SMART APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2005 [triangle]) T min = 0.896, T max = 0.957
  • 20326 measured reflections
  • 6385 independent reflections
  • 5630 reflections with I > 2σ(I)
  • R int = 0.023

Refinement

  • R[F 2 > 2σ(F 2)] = 0.037
  • wR(F 2) = 0.103
  • S = 1.04
  • 6385 reflections
  • 248 parameters
  • 1 restraint
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.54 e Å−3
  • Δρmin = −0.26 e Å−3

Data collection: APEX2 (Bruker, 2005 [triangle]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2005 [triangle]); program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808037161/ng2515sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808037161/ng2515Isup2.hkl

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

Acknowledgments

FHK and SRJ thank the Malaysian Government and Universiti Sains Malaysia for the Science Fund grant No. 305/PFIZIK/613312. SRJ thanks Universiti Sains Malaysia for a postdoctoral research fellowship.

supplementary crystallographic information

Comment

Heterocyclic compounds occur very widely in nature and are essential to life. Nitrogen-containing heterocyclic molecules constitute the largest portion of chemical entities, which are part of many natural products, fine chemicals, and biologically active pharmaceuticals vital for enhancing the quality of life. 4,5-Dihydro-pyrazoles, pyrazolidines and 1,2-dihydro-phthalazines are important classes of heterocycles useful as pesticides, anticonvulsants, and potent vasorelaxing agents (Kalluraya et al., 2001; Watanabe et al., 1998; Yuhong & Rajender, 2005). The pyrazoline function is quite stable and has inspired chemists to utilize this stable fragment in bioactive moieties to synthesize new compounds. Prompted by these review, we have synthesized this new substituted pyrazoline derivative and report its crystal structure.

Bond lengths and angles in (I) (Fig. 1) are found to have normal values (Allen et al., 1987). The dihedral angle formed by the pyrazole (N1/N2/C7—C9) ring with the pyridine ring (N3/C17—C21) and the two benzene rings (C1—C6; C10—C15) are 6.80 (5), 9.23 (5) and 74.96 (5)° respectively. The benzene rings (C1—C6; C10—C15) form dihedral angle of 80.14 (2)°, indicating that they are inclined to each other. Intramolecular C—H···N and O—H···O hydrogen bonds generate S(6) ring motifs. (Bernstein et al., 1995).

The crystal packing is consolidated by intermolecular O—H···N and C—H···O hydrogen bonding (Table 1). Furthermore, the packing is strengthened by π—π stacking interactions involving the pyrazole (N1—N2/C7—C9) (Cg1) ring and the symmetry related benzene (C10—C15) (Cg4) ring [Cg1···Cg4v=3.7787 (6) Å; symmetry code: (v) X,Y,Z]; pyridine (N3/C17—C21) (Cg2) ring and the symmetry related benzene (C1—C6) (Cg3) ring [Cg2···Cg3vi=3.6247 (5) Å; symmetry code: (vi) –X,-Y,2-Z] and between symmetry related benzene (C1—C6) (Cg3) rings [Cg3···Cg3vii = 3.7205 (5) Å; symmetry code: (vii) –X,1-Y,2-Z] together with intermolecular O···N = 2.7682 (11)Å short contacts. In the crystal packing, the molecules are linked into infinite one dimensional chains along the [100] direction (Fig 2).

Experimental

A mixture of 1-phenyl-3-(4-chloro phenyl)-2,3-di-bromo propan-1-one (0.01 mol), nicotinic hydrazide (0.01 mol) and trimethylamine (0.04 mol) in ethanol (30 mL) was refluxed for 8 h. The contents were poured onto crushed ice with stirring. The solid mass separated was collected and recrystallized from ethanol.

Refinement

The hydroxy H atoms were located in a difference map and refined with restraints of O—H=0.82 (1) Å. The remaining H atoms were positioned geometrically [C—H=0.93Å (aromatic) or 0.97Å (methylene)] and refined using a riding model, with Uiso(H)=1.2Uequ(aromatic C, methylene).

Figures

Fig. 1.
The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom numbering scheme.
Fig. 2.
The crystal packing of the title compound,viewed down the a axis.

Crystal data

C21H16ClN3O2Z = 2
Mr = 377.82F000 = 392
Triclinic, P1Dx = 1.411 Mg m3
Hall symbol: -P 1Mo Kα radiation λ = 0.71073 Å
a = 7.5916 (1) ÅCell parameters from 9943 reflections
b = 9.7644 (1) Åθ = 3.1–37.5º
c = 12.5474 (2) ŵ = 0.24 mm1
α = 104.424 (1)ºT = 100.0 (1) K
β = 94.960 (1)ºBlock, colourless
γ = 96.081 (1)º0.47 × 0.29 × 0.19 mm
V = 889.55 (2) Å3

Data collection

Bruker SMART APEXII CCD area-detector diffractometer6385 independent reflections
Radiation source: fine-focus sealed tube5630 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.023
T = 100.0(1) Kθmax = 32.5º
[var phi] and ω scansθmin = 1.7º
Absorption correction: multi-scan(SADABS; Bruker, 2005)h = −11→11
Tmin = 0.896, Tmax = 0.957k = −14→14
20326 measured reflectionsl = −18→18

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.037H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.104  w = 1/[σ2(Fo2) + (0.0577P)2 + 0.2362P] where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max < 0.001
6385 reflectionsΔρmax = 0.54 e Å3
248 parametersΔρmin = −0.26 e Å3
1 restraintExtinction correction: none
Primary atom site location: structure-invariant direct methods

Special details

Experimental. The data was collected with the Oxford Cyrosystem Cobra low-temperature attachment.
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
Cl1−0.18759 (3)0.58111 (2)1.24148 (2)0.02272 (7)
O10.24543 (9)−0.22304 (7)0.66899 (5)0.01553 (13)
O20.47798 (8)−0.05281 (7)0.85593 (5)0.01450 (12)
N10.05961 (10)0.04156 (8)0.85564 (6)0.01321 (13)
N20.17594 (9)−0.03622 (8)0.79391 (6)0.01266 (13)
N3−0.36717 (10)−0.27300 (9)0.73008 (7)0.01823 (15)
C1−0.11452 (12)0.23011 (9)1.01516 (7)0.01448 (15)
H1A−0.18210.14480.97520.017*
C2−0.19255 (12)0.32951 (10)1.08935 (7)0.01548 (16)
H2A−0.31190.31131.09940.019*
C3−0.08985 (13)0.45689 (9)1.14851 (7)0.01577 (16)
C40.08865 (13)0.48666 (9)1.13548 (7)0.01624 (16)
H4A0.15550.57221.17560.019*
C50.16553 (12)0.38617 (9)1.06134 (7)0.01500 (15)
H5A0.28520.40471.05230.018*
C60.06584 (11)0.25743 (9)1.00002 (7)0.01290 (14)
C70.15147 (11)0.15330 (9)0.92314 (7)0.01247 (14)
C80.34900 (11)0.16151 (9)0.91685 (7)0.01392 (15)
H8A0.41180.15210.98480.017*
H8B0.39610.25100.90300.017*
C90.36523 (11)0.03425 (9)0.81857 (7)0.01211 (14)
C100.42505 (12)0.08305 (9)0.71939 (7)0.01367 (15)
C110.60717 (13)0.11624 (10)0.71445 (8)0.01826 (17)
H11A0.69010.10360.76900.022*
C120.66489 (15)0.16839 (11)0.62776 (9)0.0236 (2)
H12A0.78630.19030.62480.028*
C130.54216 (16)0.18775 (11)0.54588 (8)0.0245 (2)
H13A0.58100.22080.48740.029*
C140.36126 (16)0.15747 (11)0.55197 (8)0.0227 (2)
H14A0.27860.17180.49790.027*
C150.30233 (13)0.10574 (10)0.63848 (8)0.01771 (16)
H15A0.18070.08630.64220.021*
C160.12920 (11)−0.16587 (9)0.71942 (7)0.01213 (14)
C17−0.05871 (11)−0.24069 (9)0.69814 (7)0.01225 (14)
C18−0.08787 (12)−0.36918 (10)0.61570 (8)0.01686 (16)
H18A0.0050−0.40160.57680.020*
C19−0.25619 (13)−0.44831 (10)0.59202 (8)0.01974 (18)
H19A−0.2776−0.53440.53760.024*
C20−0.39171 (12)−0.39616 (10)0.65129 (8)0.01884 (17)
H20A−0.5044−0.44920.63550.023*
C21−0.20374 (11)−0.19778 (10)0.75323 (8)0.01554 (16)
H21A−0.1862−0.11280.80880.019*
H1O20.488 (2)−0.1208 (13)0.8037 (10)0.026 (4)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Cl10.02952 (12)0.01698 (11)0.02199 (12)0.00842 (8)0.01020 (9)0.00106 (8)
O10.0147 (3)0.0150 (3)0.0160 (3)0.0030 (2)0.0043 (2)0.0011 (2)
O20.0147 (3)0.0148 (3)0.0141 (3)0.0036 (2)0.0005 (2)0.0036 (2)
N10.0140 (3)0.0118 (3)0.0129 (3)0.0026 (2)0.0031 (2)0.0008 (2)
N20.0110 (3)0.0120 (3)0.0133 (3)0.0011 (2)0.0025 (2)0.0000 (2)
N30.0120 (3)0.0183 (4)0.0217 (4)0.0009 (3)−0.0001 (3)0.0015 (3)
C10.0157 (3)0.0130 (4)0.0143 (4)0.0018 (3)0.0019 (3)0.0028 (3)
C20.0169 (4)0.0154 (4)0.0151 (4)0.0038 (3)0.0035 (3)0.0045 (3)
C30.0218 (4)0.0131 (4)0.0134 (4)0.0057 (3)0.0045 (3)0.0030 (3)
C40.0214 (4)0.0118 (4)0.0146 (4)0.0016 (3)0.0029 (3)0.0015 (3)
C50.0170 (4)0.0126 (4)0.0142 (4)0.0007 (3)0.0022 (3)0.0018 (3)
C60.0156 (3)0.0113 (3)0.0115 (3)0.0022 (3)0.0019 (3)0.0023 (3)
C70.0141 (3)0.0115 (3)0.0118 (3)0.0018 (3)0.0019 (3)0.0027 (3)
C80.0135 (3)0.0138 (4)0.0123 (3)0.0003 (3)0.0017 (3)0.0000 (3)
C90.0111 (3)0.0126 (3)0.0121 (3)0.0006 (3)0.0012 (3)0.0026 (3)
C100.0172 (4)0.0110 (3)0.0124 (3)0.0010 (3)0.0033 (3)0.0021 (3)
C110.0186 (4)0.0180 (4)0.0175 (4)−0.0013 (3)0.0045 (3)0.0039 (3)
C120.0289 (5)0.0178 (4)0.0233 (5)−0.0033 (4)0.0120 (4)0.0035 (3)
C130.0433 (6)0.0135 (4)0.0177 (4)−0.0002 (4)0.0113 (4)0.0047 (3)
C140.0382 (6)0.0153 (4)0.0153 (4)0.0045 (4)0.0017 (4)0.0055 (3)
C150.0228 (4)0.0149 (4)0.0156 (4)0.0031 (3)0.0017 (3)0.0043 (3)
C160.0133 (3)0.0116 (3)0.0111 (3)0.0014 (3)0.0011 (3)0.0023 (3)
C170.0122 (3)0.0115 (3)0.0123 (3)0.0017 (3)0.0002 (3)0.0022 (3)
C180.0165 (4)0.0141 (4)0.0169 (4)0.0008 (3)0.0013 (3)−0.0009 (3)
C190.0192 (4)0.0150 (4)0.0203 (4)−0.0015 (3)−0.0008 (3)−0.0017 (3)
C200.0149 (4)0.0181 (4)0.0205 (4)−0.0017 (3)−0.0023 (3)0.0025 (3)
C210.0126 (3)0.0143 (4)0.0177 (4)0.0016 (3)0.0006 (3)0.0007 (3)

Geometric parameters (Å, °)

Cl1—C31.7373 (9)C8—H8A0.9700
O1—C161.2311 (10)C8—H8B0.9700
O2—C91.3994 (11)C9—C101.5262 (12)
O2—H1O20.823 (9)C10—C151.3928 (13)
N1—C71.2924 (11)C10—C111.3965 (12)
N1—N21.3870 (10)C11—C121.3948 (13)
N2—C161.3638 (11)C11—H11A0.9300
N2—C91.4972 (11)C12—C131.3885 (17)
N3—C201.3367 (12)C12—H12A0.9300
N3—C211.3422 (11)C13—C141.3866 (16)
C1—C21.3880 (12)C13—H13A0.9300
C1—C61.4053 (12)C14—C151.3938 (13)
C1—H1A0.9300C14—H14A0.9300
C2—C31.3929 (13)C15—H15A0.9300
C2—H2A0.9300C16—C171.5021 (11)
C3—C41.3879 (13)C17—C181.3957 (12)
C4—C51.3889 (12)C17—C211.3966 (12)
C4—H4A0.9300C18—C191.3889 (12)
C5—C61.4003 (12)C18—H18A0.9300
C5—H5A0.9300C19—C201.3876 (14)
C6—C71.4652 (12)C19—H19A0.9300
C7—C81.5032 (12)C20—H20A0.9300
C8—C91.5412 (12)C21—H21A0.9300
C9—O2—H1O2108.8 (10)C10—C9—C8111.83 (7)
C7—N1—N2108.27 (7)C15—C10—C11119.31 (8)
C16—N2—N1125.12 (7)C15—C10—C9121.51 (8)
C16—N2—C9121.54 (7)C11—C10—C9118.99 (8)
N1—N2—C9113.32 (7)C12—C11—C10120.09 (9)
C20—N3—C21118.29 (8)C12—C11—H11A120.0
C2—C1—C6120.46 (8)C10—C11—H11A120.0
C2—C1—H1A119.8C13—C12—C11120.40 (10)
C6—C1—H1A119.8C13—C12—H12A119.8
C1—C2—C3119.15 (8)C11—C12—H12A119.8
C1—C2—H2A120.4C14—C13—C12119.51 (9)
C3—C2—H2A120.4C14—C13—H13A120.2
C4—C3—C2121.67 (8)C12—C13—H13A120.2
C4—C3—Cl1119.23 (7)C13—C14—C15120.49 (10)
C2—C3—Cl1119.10 (7)C13—C14—H14A119.8
C3—C4—C5118.69 (8)C15—C14—H14A119.8
C3—C4—H4A120.7C10—C15—C14120.18 (9)
C5—C4—H4A120.7C10—C15—H15A119.9
C4—C5—C6121.12 (8)C14—C15—H15A119.9
C4—C5—H5A119.4O1—C16—N2118.64 (8)
C6—C5—H5A119.4O1—C16—C17119.41 (8)
C5—C6—C1118.91 (8)N2—C16—C17121.95 (7)
C5—C6—C7119.70 (8)C18—C17—C21117.32 (8)
C1—C6—C7121.37 (8)C18—C17—C16115.35 (7)
N1—C7—C6121.37 (8)C21—C17—C16127.30 (8)
N1—C7—C8113.88 (7)C19—C18—C17119.68 (9)
C6—C7—C8124.71 (7)C19—C18—H18A120.2
C7—C8—C9103.47 (7)C17—C18—H18A120.2
C7—C8—H8A111.1C20—C19—C18118.56 (9)
C9—C8—H8A111.1C20—C19—H19A120.7
C7—C8—H8B111.1C18—C19—H19A120.7
C9—C8—H8B111.1N3—C20—C19122.80 (8)
H8A—C8—H8B109.0N3—C20—H20A118.6
O2—C9—N2111.30 (7)C19—C20—H20A118.6
O2—C9—C10113.38 (7)N3—C21—C17123.34 (8)
N2—C9—C10110.73 (7)N3—C21—H21A118.3
O2—C9—C8108.31 (7)C17—C21—H21A118.3
N2—C9—C8100.55 (6)
C7—N1—N2—C16175.28 (8)N2—C9—C10—C1521.78 (11)
C7—N1—N2—C9−3.15 (10)C8—C9—C10—C15−89.47 (10)
C6—C1—C2—C30.11 (13)O2—C9—C10—C11−37.34 (11)
C1—C2—C3—C4−0.26 (14)N2—C9—C10—C11−163.27 (8)
C1—C2—C3—Cl1−179.91 (7)C8—C9—C10—C1185.48 (10)
C2—C3—C4—C50.00 (14)C15—C10—C11—C12−1.49 (14)
Cl1—C3—C4—C5179.66 (7)C9—C10—C11—C12−176.55 (8)
C3—C4—C5—C60.41 (14)C10—C11—C12—C130.03 (15)
C4—C5—C6—C1−0.56 (13)C11—C12—C13—C141.25 (15)
C4—C5—C6—C7−179.54 (8)C12—C13—C14—C15−1.05 (15)
C2—C1—C6—C50.29 (13)C11—C10—C15—C141.69 (14)
C2—C1—C6—C7179.26 (8)C9—C10—C15—C14176.63 (8)
N2—N1—C7—C6179.99 (7)C13—C14—C15—C10−0.43 (14)
N2—N1—C7—C8−1.91 (10)N1—N2—C16—O1179.18 (8)
C5—C6—C7—N1−171.57 (8)C9—N2—C16—O1−2.51 (12)
C1—C6—C7—N19.47 (13)N1—N2—C16—C17−1.32 (13)
C5—C6—C7—C810.55 (13)C9—N2—C16—C17176.99 (7)
C1—C6—C7—C8−168.42 (8)O1—C16—C17—C18−3.55 (12)
N1—C7—C8—C95.84 (10)N2—C16—C17—C18176.95 (8)
C6—C7—C8—C9−176.14 (8)O1—C16—C17—C21174.65 (9)
C16—N2—C9—O2−57.55 (10)N2—C16—C17—C21−4.85 (14)
N1—N2—C9—O2120.95 (8)C21—C17—C18—C19−0.15 (14)
C16—N2—C9—C1069.54 (10)C16—C17—C18—C19178.25 (8)
N1—N2—C9—C10−111.97 (8)C17—C18—C19—C200.35 (15)
C16—N2—C9—C8−172.11 (8)C21—N3—C20—C19−0.70 (15)
N1—N2—C9—C86.39 (9)C18—C19—C20—N30.08 (16)
C7—C8—C9—O2−123.48 (7)C20—N3—C21—C170.92 (14)
C7—C8—C9—N2−6.68 (8)C18—C17—C21—N3−0.51 (14)
C7—C8—C9—C10110.87 (8)C16—C17—C21—N3−178.68 (9)
O2—C9—C10—C15147.71 (8)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O2—H1O2···O10.824 (13)2.340 (14)2.8463 (9)120.3 (13)
O2—H1O2···N3i0.824 (13)2.027 (14)2.7682 (11)149.5 (14)
C8—H8A···O2ii0.972.553.4836 (11)163
C13—H13A···O1iii0.932.463.3294 (12)156
C21—H21A···N10.932.212.8600 (12)127
C14—H14A···Cg2iv0.932.903.6968 (11)144

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: NG2515).

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