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Acta Crystallogr Sect E Struct Rep Online. 2010 April 1; 66(Pt 4): o858.
Published online 2010 March 17. doi:  10.1107/S1600536810009049
PMCID: PMC2983908

2-(2-Fluoro­biphenyl-4-yl)-N′-(propan-2-yl­idene)propanohydrazide

Abstract

In the title compound, C18H19FN2O, the hydrazide side chain is approximately perpendicular to the central ring [dihedral angle = 76.80 (5)°]. The F atom is disordered over two positions with occupancies of 0.818 (2) and 0.182 (2). The packing consists of chains of mol­ecules parallel to the a axis, connected by a bifurcated N—H(...)(O,N) hydrogen bond and a weak Cphen­yl—H(...)O hydrogen bond. The packing is extended to a layer structure parallel to the ab plane by a weak Cphen­yl—H(...)F hydrogen bond.

Related literature

For the biological activity of hydrazides, see: Kumar et al. (2009 [triangle]); Galal et al.(2009 [triangle]); Bordoloi et al. (2009 [triangle]). For their use as inter­mediates in the synthesis of heterocyclic compounds, see: Küçükgüzel et al. (2007 [triangle]); Navidpour et al. (2006 [triangle]); Stocks et al. (2004 [triangle]). For details of the preparation, see: Furniss et al. (1989 [triangle]).

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Object name is e-66-0o858-scheme1.jpg

Experimental

Crystal data

  • C18H19FN2O
  • M r = 298.35
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-66-0o858-efi1.jpg
  • a = 7.5963 (3) Å
  • b = 7.3633 (3) Å
  • c = 27.7430 (11) Å
  • V = 1551.77 (11) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 100 K
  • 0.3 × 0.2 × 0.2 mm

Data collection

  • Oxford Diffraction Xcalibur E diffractometer
  • 33827 measured reflections
  • 2221 independent reflections
  • 2019 reflections with I > 2σ(I)
  • R int = 0.033

Refinement

  • R[F 2 > 2σ(F 2)] = 0.031
  • wR(F 2) = 0.076
  • S = 1.00
  • 2221 reflections
  • 210 parameters
  • 2 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.26 e Å−3
  • Δρmin = −0.17 e Å−3

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

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810009049/bt5206sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810009049/bt5206Isup2.hkl

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

supplementary crystallographic information

Comment

Hydrazides represent one of the most biologically active class of compounds, possessing a wide spectrum of activities such as anti-microbial (Kumar et al., 2009), anti-cancer (Galal et al., 2009) and anti-genotoxic (Bordoloi et al., 2009). They have been used as intermediates in the synthesis of a number of heterocyclic compounds such as oxadiazoles, triazoles and thiadiazoles (Küçükgüzel et al. 2007; Navidpour et al., 2006; Stocks et al., 2004). The title compound (I) was synthesized as an intermediate for onward conversion to 1,2,4-triazoles and 1,3,4-thiadiazoles and in order to explore their anti-bacterial, urease inhibition and anti-fungal activities.

The molecule of (I) is shown in Fig. 1. Molecular dimensions such as the bond lengths C16═N1 1.280 (2) or N1—N2 1.3896 (17) Å may be regarded as normal. The central ring C1–6 subtends interplanar angles of 44.25 (5)° with the ring C7–12 and 76.80 (5)° with the extended hydrazide moiety C13,15,16,17,N1,N2,O (r.m.s. deviation from latter plane 0.056 Å).

The N—H function of the hydrazide group acts as donor in a three-centre hydrogen bond to O and N1 of a molecule related by the a glide plane. The weak hydrogen bond C2—H2···O acts via the same operator, and these interactions lead to chains of molecules parallel to the a axis. The contact C6—H6···F via b axis translation connects the chains to form layers of molecules parallel to the ab plane (Fig. 2).

Experimental

Methyl 4-ethoxybenzoate (0.02 moles) was dissolved in 40 ml methanol in a round-bottom flask fitted with a reflux condenser and a calcium chloride drying tube. Hydrazine hydrate (80%, 0.04 moles) was added slowly and the progress of the reaction was monitored by thin layer chromatography. After completion of the reaction, the contents were concentrated under reduced pressure (Furniss et al., 1989). The resulting crude solid was filtered, washed with water and agitated with freshly distilled acetone for 1 h. The product was recrystallized from aqueous ethanol.

Refinement

The NH hydrogen was refined freely. Methyl hydrogens were identified in difference syntheses, idealised and refined as rigid groups with C—H 0.98 Å and H—C—H angles 109.5°, allowed to rotate but not tip. Other hydrogens were placed in calculated positions and refined using a riding model with C—Harom 0.95 and C—Hmethine 1.00 Å; the hydrogen U values were fixed at 1.5 (methyl) or 1.2 × U(eq) of the parent atom.

The fluorine atom is disordered over the two sites at C3 and C5 with occupancies 0.818 (2),0.182 (2). The methyl hydrogens at C18 are treated as an idealised hexagon (disordered over two equally occupied sites) and the short contact to O may not be structurally significant.

In the absence of significant anomalous dispersion, the Friedel opposites were merged and the Flack parameter is thus meaningless.

Figures

Fig. 1.
The molecule of the title compound. Ellipsoids correspond to 50% probability levels. The minor disorder component is omitted.
Fig. 2.
Packing diagram of the title compound viewed parallel to the z axis in the region z≈ 0. Classical (three-centre) H bonds are indicated by thick dashed lines and "weak" H bonds by thin dashed lines. For clarity, the ring C7–12 is represented ...

Crystal data

C18H19FN2ODx = 1.277 Mg m3
Mr = 298.35Melting point = 403–405 K
Orthorhombic, Pca21Mo Kα radiation, λ = 0.71073 Å
a = 7.5963 (3) ÅCell parameters from 14388 reflections
b = 7.3633 (3) Åθ = 2.7–30.7°
c = 27.7430 (11) ŵ = 0.09 mm1
V = 1551.77 (11) Å3T = 100 K
Z = 4Block, colourless
F(000) = 6320.3 × 0.2 × 0.2 mm

Data collection

Oxford Diffraction Xcalibur E diffractometer2019 reflections with I > 2σ(I)
Radiation source: Enhance (Mo) X-ray SourceRint = 0.033
graphiteθmax = 29.6°, θmin = 2.8°
Detector resolution: 16.1419 pixels mm-1h = −10→10
ω scank = −10→10
33827 measured reflectionsl = −37→38
2221 independent reflections

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)] = 0.031Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.076H atoms treated by a mixture of independent and constrained refinement
S = 1.00w = 1/[σ2(Fo2) + (0.054P)2] where P = (Fo2 + 2Fc2)/3
2221 reflections(Δ/σ)max = 0.004
210 parametersΔρmax = 0.26 e Å3
2 restraintsΔρmin = −0.17 e Å3

Special details

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.Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)6.3713 (0.0030) x + 4.0007 (0.0044) y - 1.0030 (0.0204) z = 5.8734 (0.0077)* -0.0031 (0.0011) C7 * 0.0023 (0.0012) C8 * 0.0002 (0.0014) C9 * -0.0018 (0.0013) C10 * 0.0009 (0.0012) C11 * 0.0016 (0.0012) C12Rms deviation of fitted atoms = 0.0019- 6.9258 (0.0030) x + 0.8494 (0.0036) y + 10.9376 (0.0231) z = 0.9826 (0.0143)Angle to previous plane (with approximate esd) = 44.25 ( 0.05 )* -0.0036 (0.0011) C1 * 0.0203 (0.0014) C2 * 0.0261 (0.0012) C3 * -0.0276 (0.0010) F_a * 0.0066 (0.0017) C4 * -0.0181 (0.0021) C5 * 0.0140 (0.0023) F'_b * -0.0177 (0.0014) C6Rms deviation of fitted atoms = 0.01863.4515 (0.0049) x - 4.4863 (0.0030) y + 18.0294 (0.0071) z = 11.4681 (0.0049)Angle to previous plane (with approximate esd) = 76.80 ( 0.05 )* -0.0272 (0.0009) C13 * 0.0140 (0.0012) C15 * -0.0802 (0.0013) C16 * -0.0112 (0.0011) C17 * 0.1063 (0.0013) N1 * 0.0372 (0.0012) N2 * -0.0387 (0.0006) ORms deviation of fitted atoms = 0.0557
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*/UeqOcc. (<1)
C10.72830 (18)0.4169 (2)0.51831 (5)0.0147 (3)
C20.7404 (2)0.6049 (2)0.51357 (5)0.0174 (3)
H20.78760.67640.53900.021*
C30.68322 (19)0.6863 (2)0.47155 (5)0.0176 (3)
H30.69230.81460.46900.021*0.182 (2)
F0.70634 (17)0.86695 (15)0.46725 (4)0.0264 (3)0.818 (2)
C40.61277 (19)0.5909 (2)0.43257 (5)0.0161 (3)
C50.60263 (19)0.4025 (2)0.43852 (5)0.0174 (3)
H50.55620.33080.41310.021*0.818 (2)
F'0.5315 (7)0.3049 (7)0.40400 (17)0.021*0.182 (2)
C60.65842 (18)0.31696 (19)0.48053 (6)0.0166 (3)
H60.64850.18880.48340.020*
C70.55385 (19)0.6825 (2)0.38780 (6)0.0185 (3)
C80.5944 (2)0.6080 (2)0.34264 (6)0.0270 (3)
H80.66260.50010.34060.032*
C90.5349 (3)0.6917 (3)0.30082 (7)0.0377 (5)
H90.56240.64030.27030.045*
C100.4364 (3)0.8486 (3)0.30319 (7)0.0382 (5)
H100.39620.90460.27440.046*
C110.3960 (2)0.9247 (3)0.34731 (7)0.0331 (4)
H110.32841.03310.34890.040*
C120.4548 (2)0.8419 (2)0.38960 (6)0.0248 (3)
H120.42700.89460.41990.030*
C130.79126 (17)0.33065 (19)0.56537 (5)0.0148 (3)
H130.90160.39370.57570.018*
C140.8295 (2)0.1268 (2)0.56215 (6)0.0204 (3)
H14A0.71950.06090.55620.031*
H14B0.88140.08500.59250.031*
H14C0.91200.10390.53570.031*
C150.64955 (18)0.36582 (19)0.60353 (5)0.0145 (3)
C160.5793 (2)0.6916 (2)0.69282 (6)0.0204 (3)
C170.4463 (2)0.7287 (3)0.73133 (7)0.0292 (4)
H17A0.35190.63820.72950.044*
H17B0.39670.85030.72670.044*
H17C0.50310.72180.76300.044*
C180.7172 (3)0.8334 (3)0.68449 (8)0.0398 (5)
H18A0.78860.79980.65650.060*0.50
H18B0.79280.84260.71300.060*0.50
H18C0.66040.95080.67860.060*0.50
H18D0.70590.92900.70890.060*0.50
H18E0.70170.88620.65230.060*0.50
H18F0.83410.77790.68680.060*0.50
O0.51235 (13)0.27749 (14)0.60489 (4)0.0192 (2)
N10.56165 (16)0.54268 (18)0.66949 (5)0.0185 (3)
N20.68360 (16)0.50682 (18)0.63339 (5)0.0169 (3)
H010.785 (3)0.562 (3)0.6336 (8)0.036 (6)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0117 (6)0.0169 (7)0.0155 (7)0.0008 (5)0.0022 (5)0.0009 (5)
C20.0180 (6)0.0160 (7)0.0182 (7)−0.0017 (5)0.0010 (5)−0.0020 (5)
C30.0208 (6)0.0132 (6)0.0188 (7)−0.0002 (5)0.0030 (6)0.0013 (6)
F0.0436 (7)0.0107 (5)0.0249 (6)−0.0022 (5)−0.0030 (5)0.0015 (4)
C40.0143 (6)0.0174 (7)0.0167 (7)0.0012 (5)0.0024 (5)0.0000 (5)
C50.0167 (6)0.0175 (7)0.0180 (7)−0.0011 (5)−0.0003 (5)−0.0024 (6)
C60.0173 (6)0.0130 (6)0.0195 (7)0.0004 (5)0.0012 (5)−0.0010 (5)
C70.0172 (6)0.0192 (7)0.0192 (7)−0.0033 (5)−0.0012 (5)0.0038 (6)
C80.0348 (9)0.0253 (8)0.0210 (8)−0.0040 (7)0.0003 (7)0.0008 (7)
C90.0572 (12)0.0355 (11)0.0204 (8)−0.0150 (9)−0.0073 (8)0.0029 (8)
C100.0443 (11)0.0380 (10)0.0324 (10)−0.0160 (9)−0.0173 (9)0.0178 (9)
C110.0237 (8)0.0333 (9)0.0424 (11)−0.0010 (7)−0.0048 (8)0.0176 (9)
C120.0212 (7)0.0260 (8)0.0273 (8)0.0019 (6)0.0020 (6)0.0065 (7)
C130.0122 (6)0.0156 (6)0.0168 (7)0.0001 (5)0.0000 (5)−0.0002 (5)
C140.0212 (7)0.0167 (7)0.0231 (8)0.0042 (5)0.0008 (6)0.0007 (6)
C150.0139 (6)0.0148 (6)0.0147 (6)0.0023 (5)−0.0020 (5)0.0019 (5)
C160.0188 (7)0.0219 (7)0.0206 (8)0.0015 (6)0.0003 (6)−0.0009 (6)
C170.0313 (9)0.0259 (8)0.0303 (9)0.0017 (7)0.0109 (7)−0.0046 (7)
C180.0399 (11)0.0302 (9)0.0492 (12)−0.0126 (8)0.0197 (9)−0.0177 (9)
O0.0148 (5)0.0201 (5)0.0226 (5)−0.0028 (4)0.0010 (4)−0.0004 (5)
N10.0138 (5)0.0228 (6)0.0190 (6)0.0019 (5)0.0016 (5)−0.0025 (5)
N20.0111 (5)0.0207 (6)0.0190 (6)−0.0006 (5)0.0004 (5)−0.0036 (5)

Geometric parameters (Å, °)

C1—C61.386 (2)C2—H20.9500
C1—C21.394 (2)C3—H30.9500
C1—C131.529 (2)C5—H50.9500
C2—C31.381 (2)C6—H60.9500
C3—F1.3472 (18)C8—H80.9500
C3—C41.396 (2)C9—H90.9500
C4—C51.399 (2)C10—H100.9500
C4—C71.482 (2)C11—H110.9500
C5—F'1.314 (5)C12—H120.9500
C5—C61.391 (2)C13—H131.0000
C7—C121.395 (2)C14—H14A0.9800
C7—C81.402 (2)C14—H14B0.9800
C8—C91.389 (3)C14—H14C0.9800
C9—C101.378 (3)C17—H17A0.9800
C10—C111.381 (3)C17—H17B0.9800
C11—C121.395 (2)C17—H17C0.9800
C13—C141.532 (2)C18—H18A0.9800
C13—C151.532 (2)C18—H18B0.9800
C15—O1.2291 (17)C18—H18C0.9800
C15—N21.3530 (19)C18—H18D0.9800
C16—N11.280 (2)C18—H18E0.9800
C16—C171.495 (2)C18—H18F0.9800
C16—C181.497 (2)N2—H010.87 (3)
N1—N21.3896 (17)
C6—C1—C2118.77 (13)C9—C10—H10119.9
C6—C1—C13123.03 (13)C11—C10—H10119.9
C2—C1—C13118.19 (12)C10—C11—H11120.1
C3—C2—C1119.32 (13)C12—C11—H11120.1
F—C3—C2117.53 (14)C7—C12—H12119.7
F—C3—C4118.55 (14)C11—C12—H12119.7
C2—C3—C4123.81 (14)C1—C13—H13108.2
C3—C4—C5115.37 (13)C14—C13—H13108.2
C3—C4—C7122.42 (13)C15—C13—H13108.2
C5—C4—C7122.22 (13)C13—C14—H14A109.5
F'—C5—C6119.2 (3)C13—C14—H14B109.5
F'—C5—C4118.6 (3)H14A—C14—H14B109.5
C6—C5—C4122.08 (13)C13—C14—H14C109.5
C1—C6—C5120.65 (13)H14A—C14—H14C109.5
C12—C7—C8118.66 (14)H14B—C14—H14C109.5
C12—C7—C4121.03 (14)C16—C17—H17A109.5
C8—C7—C4120.30 (14)C16—C17—H17B109.5
C9—C8—C7120.09 (17)H17A—C17—H17B109.5
C10—C9—C8120.58 (18)C16—C17—H17C109.5
C9—C10—C11120.20 (17)H17A—C17—H17C109.5
C10—C11—C12119.82 (17)H17B—C17—H17C109.5
C7—C12—C11120.65 (16)C16—C18—H18A109.5
C1—C13—C14114.63 (12)C16—C18—H18B109.5
C1—C13—C15107.47 (11)H18A—C18—H18B109.5
C14—C13—C15109.83 (12)C16—C18—H18C109.5
O—C15—N2123.32 (14)H18A—C18—H18C109.5
O—C15—C13121.84 (13)H18B—C18—H18C109.5
N2—C15—C13114.74 (12)C16—C18—H18D109.5
N1—C16—C17116.55 (14)H18A—C18—H18D141.1
N1—C16—C18126.34 (15)H18B—C18—H18D56.3
C17—C16—C18117.10 (15)H18C—C18—H18D56.3
C16—N1—N2117.22 (13)C16—C18—H18E109.5
C15—N2—N1117.36 (12)H18A—C18—H18E56.3
C3—C2—H2120.3H18B—C18—H18E141.1
C1—C2—H2120.3H18C—C18—H18E56.3
C2—C3—H3118.1H18D—C18—H18E109.5
C4—C3—H3118.1C16—C18—H18F109.5
C6—C5—H5119.0H18A—C18—H18F56.3
C4—C5—H5119.0H18B—C18—H18F56.3
C1—C6—H6119.7H18C—C18—H18F141.1
C5—C6—H6119.7H18D—C18—H18F109.5
C9—C8—H8120.0H18E—C18—H18F109.5
C7—C8—H8120.0C15—N2—H01122.2 (15)
C10—C9—H9119.7N1—N2—H01119.6 (15)
C8—C9—H9119.7
C6—C1—C2—C3−0.1 (2)C4—C7—C8—C9178.30 (16)
C13—C1—C2—C3−179.52 (13)C7—C8—C9—C100.3 (3)
C1—C2—C3—F−176.31 (14)C8—C9—C10—C110.1 (3)
C1—C2—C3—C4−0.1 (2)C9—C10—C11—C12−0.2 (3)
F—C3—C4—C5176.22 (13)C8—C7—C12—C110.5 (2)
C2—C3—C4—C50.1 (2)C4—C7—C12—C11−178.35 (14)
F—C3—C4—C7−3.4 (2)C10—C11—C12—C7−0.1 (3)
C2—C3—C4—C7−179.51 (14)C6—C1—C13—C1419.40 (19)
C3—C4—C5—F'177.4 (3)C2—C1—C13—C14−161.26 (13)
C7—C4—C5—F'−3.0 (3)C6—C1—C13—C15−102.98 (15)
C3—C4—C5—C60.3 (2)C2—C1—C13—C1576.36 (16)
C7—C4—C5—C6179.84 (13)C1—C13—C15—O77.34 (16)
C2—C1—C6—C50.5 (2)C14—C13—C15—O−47.97 (18)
C13—C1—C6—C5179.81 (13)C1—C13—C15—N2−99.18 (14)
F'—C5—C6—C1−177.7 (3)C14—C13—C15—N2135.52 (13)
C4—C5—C6—C1−0.5 (2)C17—C16—N1—N2179.62 (13)
C3—C4—C7—C12−44.0 (2)C18—C16—N1—N21.1 (2)
C5—C4—C7—C12136.45 (16)O—C15—N2—N15.0 (2)
C3—C4—C7—C8137.17 (16)C13—C15—N2—N1−178.54 (12)
C5—C4—C7—C8−42.4 (2)C16—N1—N2—C15−169.44 (14)
C12—C7—C8—C9−0.6 (2)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N2—H01···Oi0.87 (3)2.24 (3)3.0633 (17)158 (2)
N2—H01···N1i0.87 (3)2.45 (2)3.0632 (17)127.7 (19)
C6—H6···Fii0.952.453.3537 (18)159
C2—H2···Oi0.952.523.3816 (19)150
C18—H18A···Oi0.982.293.251 (2)166

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BT5206).

References

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