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ISSN: 2056-9890

2-Chloro­benzohydrazide

aDepartment of Chemistry, G.C. University, Faisalabad 38000, Pakistan, bDepartment of Applied Sciences, National Textile University, Faisalabad 37610, Pakistan, and cUniversity of Sargodha, Department of Physics, Sargodha, Pakistan
*Correspondence e-mail: dmntahir_uos@yahoo.com

(Received 15 February 2012; accepted 23 March 2012; online 31 March 2012)

The asymmetric unit of the the title compound, C7H7ClN2O, contains two mol­ecules in which the chloro­phenyl and the formic hydrazide units are almost planar (r.m.s. deviations of 0.0081 and 0.0100 Å, respectively, in one mol­ecule and 0.0069 and 0.0150 Å in the other) and are oriented with respect to each other at dihedral angles of 56.8 (2) and 56.9 (2)°. In the crystal, the mol­ecules are consolidated in the form of polymeric chains extending along [010]. R33(10) ring motifs exist due to N—H⋯O and N—H⋯N hydrogen bonds.

Related literature

For a related structure, see: Zareef et al. (2006[Zareef, M., Iqbal, R., Qadeer, G., Wong, W.-Y., Akhtar, H. & Arfan, M. (2006). Z. Kristallogr. New Cryst. Struct. 221, 305-306.]). For graph-set notation, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). For the synthetic method, see: Moise et al. (2009[Moise, M., Sunel, V., Profire, L., Popa, M., Desbrieres, J. & Peptu, C. (2009). Molecules, 14, 2621-2631.]).

[Scheme 1]

Experimental

Crystal data
  • C7H7ClN2O

  • Mr = 170.60

  • Monoclinic, P 21 /c

  • a = 25.7589 (16) Å

  • b = 4.9618 (3) Å

  • c = 12.9205 (8) Å

  • β = 103.648 (3)°

  • V = 1604.75 (17) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.42 mm−1

  • T = 296 K

  • 0.34 × 0.14 × 0.12 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc. Madison, Wisconsin, USA.]) Tmin = 0.979, Tmax = 0.988

  • 11488 measured reflections

  • 3091 independent reflections

  • 2089 reflections with I > 2σ(I)

  • Rint = 0.039

Refinement
  • R[F2 > 2σ(F2)] = 0.083

  • wR(F2) = 0.217

  • S = 1.08

  • 3091 reflections

  • 211 parameters

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

  • Δρmax = 0.80 e Å−3

  • Δρmin = −0.47 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O1i 0.86 2.05 2.825 (5) 149
N2—H2A⋯N2ii 0.89 (6) 2.27 (6) 3.151 (7) 172 (5)
N3—H3A⋯O2iii 0.86 2.10 2.812 (5) 140
N4—H4B⋯N4iv 0.80 (6) 2.40 (6) 3.155 (6) 158 (5)
Symmetry codes: (i) x, y+1, z; (ii) [-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) x, y-1, z; (iv) [-x, y+{\script{1\over 2}}, -z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc. Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc. Madison, Wisconsin, USA.]); data reduction: SAINT; 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, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information


Comment top

The title compound (I), (Fig. 1) has been synthesized as a precursor for the preparation of various substituted triazole derivatives.

We have reported the crystal structures of N-2-bromobenzoylhydrazide (Zareef et al., 2006), which is related to (I).

In (I), two molecules are present in the asymmetric unit, which differ slightly from each other geometrically. In one molecule, the chlorophenyl group A (C1–C6/Cl1) and the formic hydrazide moiety B (O1/C7/N1/N2) are planar with r. m. s. deviations of 0.0081Å and 0.0100 Å, respectively. The dihedral angle between A/B is 56.8 (2)°. In second molecule, the chlorophenyl group C (C8–C13/Cl2) and the formic hydrazide moiety D (O2/C14/N3/N4) are also planar with r. m. s. deviation of 0.0069Å and 0.0150 Å, respectively and the dihedral angle between C/D is 56.89 (20)°. Each molecule is connected to symmetry related neighbors through classical intermolecular H–bonding of the N—H···O or N—H···N type (Table 1, Fig. 2) with R33(10) ring motifs (Bernstein et al., 1995) to generate one-dimensional polymeric chains along the [0 1 0] direction.

Related literature top

For a related structure, see: Zareef et al. (2006). For graph-set notation, see: Bernstein et al. (1995). For the synthetic method, see: Moise et al. (2009).

Experimental top

2-Chlorobenzoic acid (3.44 g, 22 mmol) was converted to methyl 2-chlorobenzoate by refluxing in methanol (20 ml) in the presence of a catalytic amount of sulfuric acid. This ester was converted into the title compound, 2-chlorobenzoylhydrazide, by refluxing with hydrazine hydrate (80 %, 10 ml) in dry methanol using the literature procedure (Moise et al., 2009). M.p. 379-380K.

Refinement top

The coordinates of the H-atoms of the NH2 groups were refined. The remaining H atoms were positioned geometrically with (N–H = 0.86 and C–H = 0.93 Å) and refined as riding with Uiso(H) = xUeq(C, N), where x = 1.2 for all H-atoms.

Structure description top

The title compound (I), (Fig. 1) has been synthesized as a precursor for the preparation of various substituted triazole derivatives.

We have reported the crystal structures of N-2-bromobenzoylhydrazide (Zareef et al., 2006), which is related to (I).

In (I), two molecules are present in the asymmetric unit, which differ slightly from each other geometrically. In one molecule, the chlorophenyl group A (C1–C6/Cl1) and the formic hydrazide moiety B (O1/C7/N1/N2) are planar with r. m. s. deviations of 0.0081Å and 0.0100 Å, respectively. The dihedral angle between A/B is 56.8 (2)°. In second molecule, the chlorophenyl group C (C8–C13/Cl2) and the formic hydrazide moiety D (O2/C14/N3/N4) are also planar with r. m. s. deviation of 0.0069Å and 0.0150 Å, respectively and the dihedral angle between C/D is 56.89 (20)°. Each molecule is connected to symmetry related neighbors through classical intermolecular H–bonding of the N—H···O or N—H···N type (Table 1, Fig. 2) with R33(10) ring motifs (Bernstein et al., 1995) to generate one-dimensional polymeric chains along the [0 1 0] direction.

For a related structure, see: Zareef et al. (2006). For graph-set notation, see: Bernstein et al. (1995). For the synthetic method, see: Moise et al. (2009).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. View of the title compound with the atom numbering scheme. The displacement ellipsoids are drawn at the 50% probability level. H-atoms are shown as small circles of arbitrary radii.
[Figure 2] Fig. 2. Partial packing diagram (PLATON; Spek, 2009) which shows that the molecules form polymeric chains extending along the [0 1 0] direction forming R33(10) ring motifs.
2-Chlorobenzohydrazide top
Crystal data top
C7H7ClN2OF(000) = 704
Mr = 170.60Dx = 1.412 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 2089 reflections
a = 25.7589 (16) Åθ = 0.8–26.0°
b = 4.9618 (3) ŵ = 0.42 mm1
c = 12.9205 (8) ÅT = 296 K
β = 103.648 (3)°Needle, colorless
V = 1604.75 (17) Å30.34 × 0.14 × 0.12 mm
Z = 8
Data collection top
Bruker Kappa APEXII CCD
diffractometer
3091 independent reflections
Radiation source: fine-focus sealed tube2089 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.039
Detector resolution: 7.6 pixels mm-1θmax = 26.0°, θmin = 0.8°
ω scansh = 3131
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
k = 65
Tmin = 0.979, Tmax = 0.988l = 1515
11488 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)] = 0.083Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.217H atoms treated by a mixture of independent and constrained refinement
S = 1.08 w = 1/[σ2(Fo2) + (0.0577P)2 + 4.8436P]
where P = (Fo2 + 2Fc2)/3
3091 reflections(Δ/σ)max < 0.001
211 parametersΔρmax = 0.80 e Å3
0 restraintsΔρmin = 0.47 e Å3
Crystal data top
C7H7ClN2OV = 1604.75 (17) Å3
Mr = 170.60Z = 8
Monoclinic, P21/cMo Kα radiation
a = 25.7589 (16) ŵ = 0.42 mm1
b = 4.9618 (3) ÅT = 296 K
c = 12.9205 (8) Å0.34 × 0.14 × 0.12 mm
β = 103.648 (3)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
3091 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
2089 reflections with I > 2σ(I)
Tmin = 0.979, Tmax = 0.988Rint = 0.039
11488 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0830 restraints
wR(F2) = 0.217H atoms treated by a mixture of independent and constrained refinement
S = 1.08Δρmax = 0.80 e Å3
3091 reflectionsΔρmin = 0.47 e Å3
211 parameters
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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
Cl10.32498 (8)0.2330 (4)0.33851 (15)0.1011 (8)
O10.45056 (16)0.1875 (7)0.4080 (3)0.0622 (15)
N10.45512 (15)0.2531 (8)0.3704 (3)0.0425 (12)
N20.49903 (18)0.2265 (9)0.3247 (4)0.0481 (16)
C10.39139 (18)0.1163 (10)0.4673 (4)0.0432 (17)
C20.3415 (2)0.0002 (13)0.4426 (4)0.067 (2)
C30.3025 (3)0.0750 (18)0.4998 (7)0.093 (3)
C40.3167 (3)0.256 (2)0.5818 (7)0.102 (4)
C50.3654 (3)0.3692 (15)0.6064 (5)0.080 (3)
C60.4023 (2)0.3033 (11)0.5501 (4)0.0570 (17)
C70.43389 (18)0.0452 (9)0.4120 (3)0.0397 (16)
Cl20.16784 (6)0.7856 (3)0.01597 (14)0.0751 (6)
O20.04466 (14)0.6942 (7)0.0529 (3)0.0583 (11)
N30.04524 (14)0.2531 (7)0.0886 (3)0.0399 (12)
N40.00065 (18)0.2615 (9)0.1749 (3)0.0461 (14)
C80.10837 (18)0.4182 (10)0.0635 (3)0.0422 (16)
C90.15626 (19)0.5612 (12)0.0799 (4)0.0546 (19)
C100.1956 (2)0.5229 (16)0.1706 (6)0.081 (3)
C110.1879 (3)0.348 (2)0.2458 (6)0.094 (3)
C120.1414 (3)0.2024 (17)0.2324 (5)0.089 (3)
C130.1015 (2)0.2401 (12)0.1409 (4)0.0598 (19)
C140.06346 (18)0.4680 (9)0.0317 (3)0.0388 (16)
H10.441180.410110.371900.0512*
H2A0.496 (2)0.082 (12)0.283 (4)0.0577*
H2B0.523 (2)0.180 (13)0.366 (4)0.0577*
H30.268200.002630.481780.1112*
H40.292130.300880.621310.1223*
H50.374010.492820.661930.0959*
H60.435640.385610.567470.0681*
H3A0.061700.102310.073050.0475*
H4A0.026 (2)0.298 (11)0.141 (4)0.0556*
H4B0.006 (2)0.363 (12)0.218 (4)0.0556*
H100.227640.617120.180400.0978*
H110.214600.325000.307710.1128*
H120.136800.080320.284120.1061*
H130.069660.144310.131690.0717*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0933 (12)0.1012 (16)0.0900 (12)0.0555 (11)0.0160 (9)0.0057 (11)
O10.083 (3)0.0225 (19)0.088 (3)0.0036 (18)0.034 (2)0.0005 (19)
N10.055 (2)0.021 (2)0.055 (2)0.0018 (17)0.0199 (19)0.0024 (18)
N20.057 (3)0.032 (2)0.060 (3)0.002 (2)0.023 (2)0.002 (2)
C10.046 (3)0.034 (3)0.050 (3)0.002 (2)0.012 (2)0.013 (2)
C20.054 (3)0.076 (5)0.067 (3)0.018 (3)0.006 (3)0.022 (3)
C30.053 (3)0.115 (7)0.112 (6)0.008 (4)0.023 (4)0.046 (5)
C40.080 (5)0.129 (8)0.112 (6)0.017 (5)0.052 (5)0.015 (6)
C50.095 (5)0.082 (5)0.073 (4)0.020 (4)0.042 (4)0.005 (4)
C60.066 (3)0.048 (3)0.062 (3)0.004 (3)0.025 (3)0.002 (3)
C70.055 (3)0.022 (3)0.041 (2)0.005 (2)0.009 (2)0.003 (2)
Cl20.0653 (9)0.0623 (10)0.1057 (12)0.0121 (8)0.0360 (8)0.0044 (9)
O20.067 (2)0.0225 (19)0.075 (2)0.0001 (16)0.0040 (18)0.0014 (17)
N30.049 (2)0.019 (2)0.048 (2)0.0053 (16)0.0041 (16)0.0001 (17)
N40.056 (2)0.034 (3)0.044 (2)0.001 (2)0.0032 (19)0.0001 (19)
C80.046 (3)0.037 (3)0.042 (2)0.008 (2)0.007 (2)0.006 (2)
C90.046 (3)0.055 (4)0.060 (3)0.009 (2)0.007 (2)0.019 (3)
C100.055 (3)0.094 (6)0.084 (5)0.005 (4)0.006 (3)0.032 (4)
C110.079 (5)0.126 (7)0.061 (4)0.036 (5)0.017 (4)0.020 (5)
C120.112 (6)0.096 (6)0.056 (4)0.051 (5)0.017 (4)0.020 (4)
C130.070 (3)0.051 (4)0.056 (3)0.007 (3)0.010 (3)0.010 (3)
C140.049 (3)0.024 (3)0.044 (2)0.002 (2)0.012 (2)0.002 (2)
Geometric parameters (Å, º) top
Cl1—C21.749 (6)C3—C41.371 (13)
Cl2—C91.743 (6)C4—C51.342 (11)
O1—C71.237 (6)C5—C61.366 (9)
O2—C141.228 (6)C3—H30.9300
N1—N21.400 (6)C4—H40.9300
N1—C71.338 (6)C5—H50.9300
N1—H10.8600C6—H60.9300
N2—H2A0.89 (6)C8—C141.497 (6)
N2—H2B0.75 (5)C8—C91.395 (7)
N3—C141.317 (6)C8—C131.377 (7)
N3—N41.421 (6)C9—C101.370 (9)
N3—H3A0.8600C10—C111.352 (11)
N4—H4A0.89 (5)C11—C121.374 (12)
N4—H4B0.80 (6)C12—C131.384 (9)
C1—C21.375 (7)C10—H100.9300
C1—C71.484 (7)C11—H110.9300
C1—C61.394 (7)C12—H120.9300
C2—C31.430 (10)C13—H130.9300
N2—N1—C7123.0 (4)C5—C4—H4119.00
C7—N1—H1118.00C3—C4—H4119.00
N2—N1—H1119.00C6—C5—H5120.00
N1—N2—H2B110 (4)C4—C5—H5120.00
H2A—N2—H2B97 (6)C1—C6—H6119.00
N1—N2—H2A112 (3)C5—C6—H6119.00
N4—N3—C14122.3 (4)C9—C8—C13118.5 (4)
C14—N3—H3A119.00C13—C8—C14119.7 (4)
N4—N3—H3A119.00C9—C8—C14121.7 (4)
N3—N4—H4B107 (4)Cl2—C9—C10118.7 (4)
H4A—N4—H4B121 (5)C8—C9—C10120.6 (5)
N3—N4—H4A101 (3)Cl2—C9—C8120.7 (4)
C6—C1—C7119.3 (4)C9—C10—C11120.0 (6)
C2—C1—C7122.9 (5)C10—C11—C12121.2 (7)
C2—C1—C6117.7 (5)C11—C12—C13119.1 (7)
Cl1—C2—C3119.8 (5)C8—C13—C12120.7 (5)
Cl1—C2—C1120.0 (4)O2—C14—C8121.5 (4)
C1—C2—C3120.2 (6)N3—C14—C8115.4 (4)
C2—C3—C4118.5 (7)O2—C14—N3123.1 (4)
C3—C4—C5121.4 (8)C9—C10—H10120.00
C4—C5—C6120.2 (7)C11—C10—H10120.00
C1—C6—C5121.9 (5)C10—C11—H11120.00
O1—C7—C1123.0 (4)C12—C11—H11119.00
N1—C7—C1115.3 (4)C11—C12—H12120.00
O1—C7—N1121.6 (4)C13—C12—H12120.00
C4—C3—H3121.00C8—C13—H13120.00
C2—C3—H3121.00C12—C13—H13120.00
N2—N1—C7—O13.4 (7)C3—C4—C5—C60.6 (13)
N2—N1—C7—C1173.6 (4)C4—C5—C6—C10.9 (10)
N4—N3—C14—O25.1 (7)C13—C8—C9—Cl2179.0 (4)
N4—N3—C14—C8173.5 (4)C13—C8—C9—C100.6 (8)
C7—C1—C2—Cl12.5 (7)C14—C8—C9—Cl25.3 (7)
C7—C1—C2—C3179.2 (6)C14—C8—C9—C10176.3 (5)
C2—C1—C6—C50.7 (8)C9—C8—C13—C120.5 (8)
C7—C1—C6—C5177.6 (5)C14—C8—C13—C12176.3 (5)
C2—C1—C7—O157.1 (7)C9—C8—C14—O254.9 (7)
C2—C1—C7—N1125.9 (5)C9—C8—C14—N3126.5 (5)
C6—C1—C7—O1121.1 (5)C13—C8—C14—O2120.7 (5)
C6—C1—C7—N155.9 (6)C13—C8—C14—N357.9 (6)
C6—C1—C2—C31.0 (9)Cl2—C9—C10—C11179.3 (6)
C6—C1—C2—Cl1179.2 (4)C8—C9—C10—C110.9 (10)
C1—C2—C3—C42.5 (11)C9—C10—C11—C121.2 (12)
Cl1—C2—C3—C4179.3 (7)C10—C11—C12—C131.2 (12)
C2—C3—C4—C52.3 (13)C11—C12—C13—C80.8 (10)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O1i0.862.052.825 (5)149
N2—H2A···N2ii0.89 (6)2.27 (6)3.151 (7)172 (5)
N3—H3A···O2iii0.862.102.812 (5)140
N4—H4B···N4iv0.80 (6)2.40 (6)3.155 (6)158 (5)
Symmetry codes: (i) x, y+1, z; (ii) x+1, y1/2, z+1/2; (iii) x, y1, z; (iv) x, y+1/2, z1/2.

Experimental details

Crystal data
Chemical formulaC7H7ClN2O
Mr170.60
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)25.7589 (16), 4.9618 (3), 12.9205 (8)
β (°) 103.648 (3)
V3)1604.75 (17)
Z8
Radiation typeMo Kα
µ (mm1)0.42
Crystal size (mm)0.34 × 0.14 × 0.12
Data collection
DiffractometerBruker Kappa APEXII CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.979, 0.988
No. of measured, independent and
observed [I > 2σ(I)] reflections
11488, 3091, 2089
Rint0.039
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.083, 0.217, 1.08
No. of reflections3091
No. of parameters211
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.80, 0.47

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O1i0.862.052.825 (5)149
N2—H2A···N2ii0.89 (6)2.27 (6)3.151 (7)172 (5)
N3—H3A···O2iii0.862.102.812 (5)140
N4—H4B···N4iv0.80 (6)2.40 (6)3.155 (6)158 (5)
Symmetry codes: (i) x, y+1, z; (ii) x+1, y1/2, z+1/2; (iii) x, y1, z; (iv) x, y+1/2, z1/2.
 

Acknowledgements

The authors acknowledge the provision of funds for the purchase of the diffractometer and encouragement by Dr Muhammad Akram Chaudhary, Vice Chancellor, University of Sargodha, Pakistan. The authors also acknowledge the technical support provided by Syed Muhammad Hussain Rizvi of Bana Inter­national, Karachi, Pakistan.

References

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