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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 70| Part 5| May 2014| Pages o532-o533

N′-[(E)-1-(2-Fluoro­phen­yl)ethyl­­idene]pyridine-4-carbohydrazide

aDepartment of Chemistry, Christ University, Hosur Road, Bangalore 560 029, Karnataka, India, bDepartment of Chemistry, Faculty of Science, Eastern University, Sri Lanka, Chenkalady, Sri Lanka, and cDepartment of Applied Chemistry, Cochin University of Science and Technology, Kochi 682 022, India
*Correspondence e-mail: eesans@yahoo.com

(Received 23 March 2014; accepted 4 April 2014; online 9 April 2014)

The title compound, C14H12FN3O, adopts an E conformation with respect to the azomethine bond. The pyridyl and fluoro­benzene rings make dihedral angles of 38.58 (6) and 41.61 (5)° respectively with the central C(=O)N2CC unit, resulting in a non-planar mol­ecule. The inter­molecular inter­actions comprise two classical N—H⋯O and N—H⋯N hydrogen bonds and four non-classical C—H⋯O and C—H⋯F hydrogen bonds. These inter­actions are augmented by a weak ππ inter­action between the benzene and pyridyl rings of neighbouring mol­ecules, with a centroid–centroid distance of 3.9226 (10) Å. This leads to a three-dimensional supra­molecular assembly in the crystal system. The F atom is disordered over two sites in a 0.559 (3): 0.441 (3) ratio, through a 180° rotation of the fluoro­benzene ring.

Related literature

For biological properties of hydrazones, see: Kahwa et al. (1986[Kahwa, I. A., Selbin, I., Hsieh, T. C. Y. & Laine, R. A. (1986). Inorg. Chim. Acta, 118, 179-185.]); Santos et al. (2001[Santos, M. L. P., Bagatin, I. A., Pereira, E. M. & Ferreira, A. M. D. C. (2001). J. Chem. Soc. Dalton Trans. pp. 838-844.]); Rollas & Kucukguzel (2007[Rollas, S. & Kucukguzel, S. G. (2007). Molecules, 12, 1910-1939.]). For the synthesis of related compounds, see: Mangalam & Kurup (2011[Mangalam, N. A. & Kurup, M. R. P. (2011). Spectrochim. Acta Part A, 78, 926-934.]). For related structures, see: Sreeja et al. (2013[Sreeja, P. B., Sithambaresan, M., Aiswarya, N. & Kurup, M. R. P. (2013). Acta Cryst. E69, o1828.], 2014[Sreeja, P. B., Sithambaresan, M., Aiswarya, N. & Kurup, M. R. P. (2014). Acta Cryst. E70, o115.]).

[Scheme 1]

Experimental

Crystal data
  • C14H12FN3O

  • Mr = 257.27

  • Monoclinic, P 21 /c

  • a = 8.2649 (6) Å

  • b = 19.2127 (14) Å

  • c = 8.0554 (5) Å

  • β = 99.244 (3)°

  • V = 1262.51 (15) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 296 K

  • 0.35 × 0.30 × 0.25 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2004[Bruker (2004). APEX2, SAINT, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.965, Tmax = 0.976

  • 9610 measured reflections

  • 3137 independent reflections

  • 2262 reflections with I > 2σ(I)

  • Rint = 0.030

Refinement
  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.152

  • S = 1.04

  • 3113 reflections

  • 179 parameters

  • 1 restraint

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

  • Δρmax = 0.24 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2′⋯N1i 0.87 (1) 2.45 (1) 3.1420 (15) 137 (1)
N2—H2′⋯O1i 0.87 (1) 2.38 (1) 3.1777 (15) 154 (2)
C8—H8C⋯F1i 0.96 2.46 3.1603 (19) 129
C8—H8C⋯O1i 0.96 2.58 3.0680 (13) 112
C13—H13⋯F1ii 0.93 2.34 3.238 (2) 161
C14—H14⋯O1i 0.93 2.50 3.1849 (19) 131
Symmetry codes: (i) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (ii) x-1, y, z-1.

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2, SAINT, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2 and SAINT (Bruker, 2004[Bruker (2004). APEX2, SAINT, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT and XPREP (Bruker, 2004[Bruker (2004). APEX2, SAINT, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and DIAMOND (Brandenburg, 2010[Brandenburg, K. (2010). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXL97 and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

The chemistry of Schiff bases has attracted a great deal of interest in recent years. These compounds play an important role in the development of various proteins and enzymes (Kahwa et al., 1986; Santos et al., 2001). A number of hydrazones derived from isoniazid were reported to be active antitubercular agents and were found to be less toxic than isoniazid (Rollas & Kucukguzel, 2007). In this paper we report the synthesis and crystal structure of the title compound.

The molecule crystallizes in monoclinic space group P21/c. The compound adopts an E configuration with respect to the azomethine olefinic bond whilst the C8 and N2 atoms are in Z configuration with respect to the same bond with torsion angles of -177.77 (8) of and 2.13 (14)° respectively (Fig. 1). The ketonic O and the azomethine N are also cis to each other with a torsion angle of 1.4 (2)°. The molecule exists in the amido form with a C9=O1 bond length of 1.2208 (16) Å which is very close to the reported C=O bond length of a similar structure (Sreeja et al., 2013). The pyridyl ring and the fluorophenyl ring make a dihedral angle of 38.58 (6) and 41.61 (5)° with the C(=O)N2CC central unit making the molecule non-planar.

There exist two classical N–H···O and N–H···N hydrogen bonding interactions with D···A distances of 3.1777 (15) and 3.1419 (15) Å respectively (Table 1). In addition to this, there are four non-classical C–H···O and C–H···F H bonding interactions present with D···A distances of 3.1603 (19), 3.0680 (13), 3.238 (2) and 3.1849 (19) Å connecting various adjacent molecules together with the main molecule (Fig. 2). The hydrogen atoms at N2 and C8 form bifurcated hydrogen bonds with O1 & N1 and F1 and O1 respectively (Fig. 2). A weak π···π interaction between the phenyl and the pyridyl ring of the neighbouring molecules also supports to form a three-dimensional supramolecular assembly together with the dominant H bonding interactions with a centroid-centroid distance of 3.9226 (10) Å (Fig. 2). Fig. 3 shows the packing of the molecules by means of hydrogen bonding and ππ interactions along a axis.

Through a 180° rotation of the fluorophenyl ring, the fluorine atom F1 is disordered over two sites in a ratio of 56.0 (1):44.0 (1). Similar instances of positional disorder had been previously reported (Sreeja et al., 2014).

Related literature top

For biological properties of hydrazones, see: Kahwa et al. (1986); Santos et al. (2001); Rollas & Kucukguzel (2007). For the synthesis of related compounds, see: Mangalam & Kurup (2011). For related structures, see: Sreeja et al. (2013, 2014).

Experimental top

The title compound was prepared by adapting a reported procedure (Mangalam & Kurup, 2011). Methanolic solutions of pyridine-4-carbohydrazide (0.137 g, 1 mmol) and 1-(2-fluorophenyl)ethanone (0.138 g, 1 mmol) was refluxed, in presence of a few drops of glacial acetic acid for 6 h. On cooling the reactant media, colourless crystals of hydrazones were separated out. The crystals were filtered and washed with minimum quantity of methanol and dried over P4O10 in vacuo. Good quality block shaped crystals suitable for X-ray analysis, were obtained from methanolic solution by slow evaporation.

Refinement top

The fluorine atoms F1 and F1B of this molecule were refined freely, with the sum of their occupancy factors constrained to 1.0. The H5 at C5 atom is placed in geometrically idealized position with occupancy factor equal to that F1, and its coordinates were fixed. The H1 atom was refined with restrained distance of 0.93 Å with occupancy factor equal to that of F1B. The N2—H2' distance was restrained to 0.88±0.01 Å. The H atoms on the rest of C atoms were placed in calculated positions, guided by difference maps, with C–H bond distances 0.93–0.96 Å. H atoms were assigned as Uiso(H)=1.2Ueq(carrier) or 1.5Ueq (methyl C).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 2010); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. ORTEP diagram of N'-[(1E)-1-(2-fluorophenyl)ethylidene]pyridine-4-carbohydrazide with 50% probability ellipsoids. The minor components of fluorine and hydrogen atoms of the disorder are omitted.
[Figure 2] Fig. 2. Hydrogen-bonding and π···π interactions in the title compound. The minor components of fluorine and hydrogen atoms of the disorder are omitted.
[Figure 3] Fig. 3. Packing diagram of the title compound along a axis.
N'-[(E)-1-(2-Fluorophenyl)ethylidene]pyridine-4-carbohydrazide top
Crystal data top
C14H12FN3OF(000) = 536
Mr = 257.27Dx = 1.354 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3938 reflections
a = 8.2649 (6) Åθ = 2.5–28.2°
b = 19.2127 (14) ŵ = 0.10 mm1
c = 8.0554 (5) ÅT = 296 K
β = 99.244 (3)°Block, colorless
V = 1262.51 (15) Å30.35 × 0.30 × 0.25 mm
Z = 4
Data collection top
Bruker Kappa APEXII CCD
diffractometer
3137 independent reflections
Radiation source: fine-focus sealed tube2262 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.030
Detector resolution: 8.33 pixels mm-1θmax = 28.3°, θmin = 2.5°
ω and ϕ scanh = 1010
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
k = 2525
Tmin = 0.965, Tmax = 0.976l = 610
9610 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.048H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.152 w = 1/[σ2(Fo2) + (0.0851P)2 + 0.152P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max < 0.001
3113 reflectionsΔρmax = 0.24 e Å3
179 parametersΔρmin = 0.21 e Å3
1 restraintExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.091 (9)
Crystal data top
C14H12FN3OV = 1262.51 (15) Å3
Mr = 257.27Z = 4
Monoclinic, P21/cMo Kα radiation
a = 8.2649 (6) ŵ = 0.10 mm1
b = 19.2127 (14) ÅT = 296 K
c = 8.0554 (5) Å0.35 × 0.30 × 0.25 mm
β = 99.244 (3)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
3137 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
2262 reflections with I > 2σ(I)
Tmin = 0.965, Tmax = 0.976Rint = 0.030
9610 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0481 restraint
wR(F2) = 0.152H atoms treated by a mixture of independent and constrained refinement
S = 1.04Δρmax = 0.24 e Å3
3113 reflectionsΔρmin = 0.21 e Å3
179 parameters
Special details top

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) top
xyzUiso*/UeqOcc. (<1)
F11.2954 (2)0.23496 (9)0.7843 (2)0.0687 (7)0.559 (3)
F1B1.1039 (4)0.01885 (12)0.6026 (3)0.0868 (11)0.441 (3)
O10.85862 (15)0.33623 (6)0.55332 (12)0.0580 (3)
N11.02285 (13)0.21790 (6)0.53744 (12)0.0407 (3)
N20.93699 (14)0.24882 (6)0.39513 (13)0.0412 (3)
N30.5574 (2)0.40011 (8)0.01035 (19)0.0675 (4)
C11.27207 (19)0.16966 (8)0.80753 (18)0.0496 (4)
H11.27970.21750.79230.059*0.441 (3)
C21.3481 (2)0.14096 (11)0.9566 (2)0.0674 (5)
H21.40560.16911.03990.081*
C31.3382 (3)0.07038 (11)0.9809 (2)0.0726 (5)
H31.38890.05051.08110.087*
C41.2544 (3)0.02970 (10)0.8585 (3)0.0734 (5)
H41.24730.01810.87460.088*
C51.17979 (10)0.05957 (4)0.71021 (9)0.0592 (4)
H51.12360.03100.62710.071*0.559 (3)
C61.18520 (10)0.13048 (4)0.68017 (9)0.0411 (3)
C71.10140 (10)0.16188 (4)0.52091 (9)0.0399 (3)
C81.11560 (10)0.12603 (4)0.35878 (9)0.0566 (4)
H8A1.02110.09720.32570.085*
H8B1.21260.09770.37350.085*
H8C1.12220.16020.27320.085*
C90.85653 (17)0.30834 (7)0.41681 (15)0.0409 (3)
C100.75600 (16)0.33873 (7)0.26301 (16)0.0390 (3)
C110.7454 (2)0.40996 (8)0.2466 (2)0.0546 (4)
H110.80470.43890.32690.066*
C120.6454 (2)0.43775 (9)0.1093 (2)0.0676 (5)
H120.63920.48600.10000.081*
C130.5681 (2)0.33184 (9)0.0080 (2)0.0604 (4)
H130.50690.30430.07410.073*
C140.66414 (18)0.29849 (8)0.14078 (18)0.0476 (3)
H140.66670.25020.14750.057*
H2'0.944 (2)0.2338 (8)0.2948 (14)0.053 (4)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
F10.0844 (14)0.0480 (10)0.0645 (11)0.0090 (8)0.0157 (9)0.0032 (8)
F1B0.129 (3)0.0477 (14)0.0729 (16)0.0225 (13)0.0185 (15)0.0026 (11)
O10.0791 (8)0.0563 (7)0.0350 (5)0.0115 (5)0.0015 (5)0.0073 (4)
N10.0442 (6)0.0490 (6)0.0280 (5)0.0044 (5)0.0026 (4)0.0053 (5)
N20.0477 (7)0.0498 (7)0.0248 (5)0.0072 (5)0.0021 (4)0.0029 (4)
N30.0639 (9)0.0691 (9)0.0618 (8)0.0087 (7)0.0132 (7)0.0126 (7)
C10.0514 (8)0.0522 (8)0.0421 (7)0.0001 (6)0.0015 (6)0.0027 (6)
C20.0646 (11)0.0874 (13)0.0435 (8)0.0005 (9)0.0116 (7)0.0025 (8)
C30.0748 (12)0.0848 (13)0.0540 (10)0.0174 (10)0.0023 (9)0.0261 (9)
C40.0912 (14)0.0584 (10)0.0680 (11)0.0085 (9)0.0046 (10)0.0226 (9)
C50.0708 (11)0.0504 (9)0.0540 (9)0.0012 (8)0.0025 (8)0.0085 (7)
C60.0409 (7)0.0462 (7)0.0356 (6)0.0027 (6)0.0043 (5)0.0051 (5)
C70.0413 (7)0.0444 (7)0.0328 (6)0.0021 (5)0.0021 (5)0.0031 (5)
C80.0755 (11)0.0520 (8)0.0381 (7)0.0112 (8)0.0038 (7)0.0036 (6)
C90.0458 (7)0.0446 (7)0.0307 (6)0.0009 (5)0.0017 (5)0.0009 (5)
C100.0393 (7)0.0440 (7)0.0334 (6)0.0040 (5)0.0050 (5)0.0009 (5)
C110.0611 (10)0.0434 (8)0.0539 (9)0.0009 (6)0.0071 (7)0.0002 (6)
C120.0733 (12)0.0476 (9)0.0741 (11)0.0041 (8)0.0117 (9)0.0125 (8)
C130.0566 (9)0.0658 (10)0.0514 (9)0.0039 (8)0.0139 (7)0.0045 (8)
C140.0492 (8)0.0455 (7)0.0452 (7)0.0031 (6)0.0013 (6)0.0030 (6)
Geometric parameters (Å, º) top
F1—C11.288 (2)C3—C41.358 (3)
F1B—C51.258 (2)C4—C51.3782 (19)
O1—C91.2208 (16)C5—C61.3856
N1—C71.2748 (13)C6—C71.4846
N1—N21.3818 (15)C7—C81.4977
N2—C91.3483 (18)C9—C101.4951 (18)
N3—C131.321 (2)C10—C111.376 (2)
N3—C121.325 (2)C10—C141.380 (2)
C1—C61.3777 (16)C11—C121.378 (2)
C1—C21.378 (2)C13—C141.383 (2)
C2—C31.374 (3)
C7—N1—N2118.60 (9)C5—C6—C7121.8
C9—N2—N1117.10 (10)N1—C7—C6115.31 (5)
C13—N3—C12116.19 (14)N1—C7—C8126.29 (5)
F1—C1—C6119.78 (13)C6—C7—C8118.4
F1—C1—C2117.28 (16)O1—C9—N2123.57 (12)
C6—C1—C2122.72 (15)O1—C9—C10120.04 (12)
C3—C2—C1119.32 (17)N2—C9—C10116.35 (11)
C4—C3—C2119.98 (16)C11—C10—C14118.00 (13)
C3—C4—C5119.64 (16)C11—C10—C9119.08 (12)
F1B—C5—C4116.26 (16)C14—C10—C9122.78 (12)
F1B—C5—C6121.17 (12)C10—C11—C12118.87 (15)
C4—C5—C6122.56 (10)N3—C12—C11124.12 (16)
C1—C6—C5115.77 (7)N3—C13—C14124.51 (15)
C1—C6—C7122.44 (7)C10—C14—C13118.29 (14)
C7—N1—N2—C9179.39 (11)C5—C6—C7—N1136.27 (7)
F1—C1—C2—C3174.5 (2)C1—C6—C7—C8136.79 (9)
C6—C1—C2—C30.1 (3)C5—C6—C7—C843.6
C1—C2—C3—C40.1 (3)N1—N2—C9—O11.4 (2)
C2—C3—C4—C50.1 (3)N1—N2—C9—C10176.38 (11)
C3—C4—C5—F1B179.8 (2)O1—C9—C10—C1137.3 (2)
C3—C4—C5—C60.6 (2)N2—C9—C10—C11144.86 (14)
F1—C1—C6—C5173.92 (14)O1—C9—C10—C14138.39 (15)
C2—C1—C6—C50.56 (18)N2—C9—C10—C1439.45 (18)
F1—C1—C6—C76.5 (2)C14—C10—C11—C120.5 (2)
C2—C1—C6—C7179.04 (12)C9—C10—C11—C12176.42 (15)
F1B—C5—C6—C1180.0 (2)C13—N3—C12—C110.6 (3)
C4—C5—C6—C10.80 (13)C10—C11—C12—N30.1 (3)
F1B—C5—C6—C70.39 (19)C12—N3—C13—C140.4 (3)
C4—C5—C6—C7178.81 (11)C11—C10—C14—C130.7 (2)
N2—N1—C7—C6177.77 (8)C9—C10—C14—C13176.42 (13)
N2—N1—C7—C82.13 (14)N3—C13—C14—C100.2 (3)
C1—C6—C7—N143.30 (10)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2···N1i0.87 (1)2.45 (1)3.1420 (15)137 (1)
N2—H2···O1i0.87 (1)2.38 (1)3.1777 (15)154 (2)
C8—H8C···F1i0.962.463.1603 (19)129
C8—H8C···O1i0.962.583.0680 (13)112
C13—H13···F1ii0.932.343.238 (2)161
C14—H14···O1i0.932.503.1849 (19)131
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x1, y, z1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2'···N1i0.869 (9)2.454 (13)3.1420 (15)136.6 (14)
N2—H2'···O1i0.869 (9)2.377 (11)3.1777 (15)153.5 (15)
C8—H8C···F1i0.96002.4603.1603 (19)129
C8—H8C···O1i0.96002.5803.0680 (13)112
C13—H13···F1ii0.93002.3403.238 (2)161
C14—H14···O1i0.93002.5003.1849 (19)131
Symmetry codes: (i) x, y+1/2, z1/2; (ii) x1, y, z1.
 

Acknowledgements

PBS thanks the Center for Research, Christ University, for financial assistance. MRPK thanks the University Grants Commission, New Delhi, for a UGC–BSR one-time grant to faculty. The authors thank the Sophisticated Analytical Instruments Facility, Cochin University of Science & Technology, for collection of the diffraction data.

References

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Volume 70| Part 5| May 2014| Pages o532-o533
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