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

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ISSN: 2056-9890

N′-(2,6-Di­chloro­benzyl­­idene)-2-hy­dr­oxy­benzohydrazide

aInstitute of Chemistry, University of the Punjab, Lahore, Pakistan, bDepartment of Chemistry, University of Sargodha, Sargodha, Pakistan, and cInstitute of Inorganic Chemistry, Leipzig University, Johannisallee 29, D-04103 Leipzig, Germany
*Correspondence e-mail: waseeqsiddiqui@gmail.com

(Received 18 August 2010; accepted 2 September 2010; online 25 September 2010)

In the title compound, C14H10Cl2N2O2, the dihedral angle between the two aromatic rings is 17.39 (4)°. An intra­molecular O—H⋯O hydrogen bond forms a six-membered R(6)11 ring motif. In the crystal structure, inter­molecular N—H⋯O and O—H⋯O hydrogen-bonding inter­actions occur.

Related literature

For the biological activity of Schiff bases, see: El-Masry et al. (2000[El-Masry, A. H., Fahmy, H. H. & Abdelwahed, S. H. A. (2000). Molecules, 5, 1429-1438.]); Samadhiya & Halve (2001[Samadhiya, S. & Halve, A. (2001). Orient. J. Chem. 17, 119-122.]). For the synthesis of Schiff bases, see: Siddiqui et al. (2006[Siddiqui, H. L., Iqbal, A., Ahmad, S. & Weaver, G. W. (2006). Molecules, 11, 206-211.]); Iqbal et al. (2007[Iqbal, A., Siddiqui, H. L., Ashraf, C. M., Ahmad, M. & Weaver, G. W. (2007). Molecules, 12, 245-254.]). For applications of Schiff bases, see: Mookherjee et al. (1989[Mookherjee, B. D., Trenkle, R. W., Calderone, N., Schreck, L. & Sands, K. P. (1989). US Patent 4 839 083 (58 pp.).]); Kumar et al. (2009[Kumar, S., Dhar, D. N. & Saxena, P. N. (2009). J. Sci. Ind. Res. 68, 181-187.]). 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.]).

[Scheme 1]

Experimental

Crystal data
  • C14H10Cl2N2O2

  • Mr = 309.14

  • Monoclinic, P 21 /c

  • a = 7.5029 (6) Å

  • b = 23.8363 (13) Å

  • c = 8.0286 (7) Å

  • β = 109.860 (6)°

  • V = 1350.45 (18) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.48 mm−1

  • T = 180 K

  • 0.34 × 0.26 × 0.18 mm

Data collection
  • Stoe IPDS-2T diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2007[Bruker (2007). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.856, Tmax = 0.921

  • 21101 measured reflections

  • 2958 independent reflections

  • 2455 reflections with I > 2σ(I)

  • Rint = 0.041

Refinement
  • R[F2 > 2σ(F2)] = 0.029

  • wR(F2) = 0.074

  • S = 1.03

  • 2958 reflections

  • 191 parameters

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

  • Δρmax = 0.24 e Å−3

  • Δρmin = −0.39 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯N2i 0.85 (2) 2.38 (2) 3.165 (2) 153 (2)
N1—H1⋯O1i 0.85 (2) 2.45 (2) 3.158 (2) 140 (1)
O2—H2A⋯O1 0.90 (2) 1.78 (2) 2.608 (2) 153 (2)
Symmetry code: (i) [x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}].

Data collection: X-AREA (Stoe & Cie, 1999[Stoe & Cie (1999). X-AREA. Stoe & Cie GmbH, Darmstadt, Germany.]); cell refinement: X-AREA; data reduction: X-AREA; 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

Schiff base reaction products of alkyl anthranilates and their derivatives have been employed in augmenting the aroma or taste of consumable materials including perfume compositions, colognes, perfumed articles, foodstuffs, chewing gums and beverages (Mookherjee et al., 1989). Related compounds have also shown to exhibit biological activities such as antibacterial, antimicrobial (El-Masry et al., 2000), and were investigated as herbicides (Samadhiya et al., 2001). Further, Schiff bases have also been employed as ligands for complexation of metal ions (Kumar et al., 2009). With this perspective of widespread applications of Schiff bases we embarked on the synthesis, characterization and biological evaluation of this class of compounds (Siddiqui et al., 2006; Iqbal et al., 2007). Herein, we report the synthesis and crystal structure of the title compound.

The title compound is presented in Fig.1. The two aromatic ring systems in the hydrazide are inclined at an angle of 17.39 (0.04) ° with respect to each other. The structure possesses classical inter and intra molecular hydrogen bonding. The intramolecular O–H···O type hydrogen bonding forms six membered ring motif R(6)11 (Bernstein et al., 1995) which inclines at an angle of 9.73 (0.14) ° with respect to aromatic C1–C6. The intermolecular C–H···O and N—H···N type of hydrogen bonding forms nine membered ring motif R(9)22 (Bernstein et al., 1995) where N–H···O type of hydrogen bonding interveins to form a six and a five membered ring system R(6)21 and R(5)12(Bernstein et al., 1995), respectively (Fig. 2, table 1).

Related literature top

For the biological activity of Schiff bases, see: El-Masry et al. (2000); Samadhiya et al. (2001). For the synthesis of Schiff bases, see: Siddiqui et al. (2006); Iqbal et al. (2007). For applications of Schiff bases, see: Mookherjee et al. (1989); Kumar et al. (2009). For graph-set notation, see: Bernstein et al. (1995).

Experimental top

A mixture of 2-hydroxy-benzoic acid hydrazide (1.5 g, 10.0 mmol) and 2,6-dichlorobenzaldehyde (1.7 g, 10.0 mmol) in absolute ethanol (20 ml) was heated to reflux (2 hrs.), cooled to room temperature and filtered. The off-white precipitates were washed with the same solvent and dried at room temperature to yield 2.8 g of off-white, needle-like crystals of the title compound (9.1 mmol, 90.6%). Suitable crystals were grown from a solution of CH3OH by slow evaporation at room temperature.

Refinement top

All aromatic H-atoms were positioned geometrically with C—H = 0.95 Å and refined using riding model with Uiso(H) = 1.2 Ueq(C), while the imine hydrogen was located in difference map and was refined with C—H = 0.95 (2) Å and Uiso(H) = 1.2 Ueq(C8). N–H and O–H H atoms also were located in difference map and were refined with N—H = 0.86 (2) Å and O—H = 0.89 (2) Å and Uiso(H) = 1.2 Ueq(N) and Uiso(H) = 1.5 Ueq(O), respectively.

Computing details top

Data collection: X-AREA (Stoe & Cie, 1999); cell refinement: X-AREA (Stoe & Cie, 1999); data reduction: X-AREA (Stoe & Cie, 1999); 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. Molecular structure of the title compound with thermal ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. Packing diagram of the crystal structure showing hydrogen bonding as dashed lines.
N'-(2,6-Dichlorobenzylidene)-2-hydroxybenzohydrazide top
Crystal data top
C14H10Cl2N2O2F(000) = 632
Mr = 309.14Dx = 1.520 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 19179 reflections
a = 7.5029 (6) Åθ = 1.7–29.5°
b = 23.8363 (13) ŵ = 0.48 mm1
c = 8.0286 (7) ÅT = 180 K
β = 109.860 (6)°Needles, white
V = 1350.45 (18) Å30.34 × 0.26 × 0.18 mm
Z = 4
Data collection top
Stoe IPDS-2T
diffractometer
2958 independent reflections
Radiation source: fine-focus sealed tube2455 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.041
ω scansθmax = 27.0°, θmin = 1.7°
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
h = 99
Tmin = 0.856, Tmax = 0.921k = 3030
21101 measured reflectionsl = 1010
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)] = 0.029H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.074 w = 1/[σ2(Fo2) + (0.0408P)2 + 0.2354P]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max = 0.001
2958 reflectionsΔρmax = 0.24 e Å3
191 parametersΔρmin = 0.39 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0085 (19)
Crystal data top
C14H10Cl2N2O2V = 1350.45 (18) Å3
Mr = 309.14Z = 4
Monoclinic, P21/cMo Kα radiation
a = 7.5029 (6) ŵ = 0.48 mm1
b = 23.8363 (13) ÅT = 180 K
c = 8.0286 (7) Å0.34 × 0.26 × 0.18 mm
β = 109.860 (6)°
Data collection top
Stoe IPDS-2T
diffractometer
2958 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
2455 reflections with I > 2σ(I)
Tmin = 0.856, Tmax = 0.921Rint = 0.041
21101 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0290 restraints
wR(F2) = 0.074H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.24 e Å3
2958 reflectionsΔρmin = 0.39 e Å3
191 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
Cl10.66364 (6)0.562338 (15)0.52580 (5)0.03982 (12)
Cl20.28455 (5)0.723630 (17)0.06158 (5)0.03924 (12)
O10.77275 (17)0.82495 (4)0.34242 (14)0.0369 (3)
O20.84369 (18)0.92793 (5)0.45517 (16)0.0431 (3)
H2A0.809 (3)0.8981 (10)0.383 (3)0.065*
N10.72285 (16)0.76179 (5)0.53258 (15)0.0239 (2)
H10.720 (2)0.7541 (7)0.636 (2)0.029*
N20.63961 (16)0.72631 (5)0.39193 (15)0.0233 (2)
C10.9163 (2)0.90454 (6)0.6187 (2)0.0308 (3)
C21.0154 (2)0.93943 (7)0.7591 (2)0.0383 (4)
H21.02620.97840.73960.046*
C31.0976 (2)0.91717 (7)0.9261 (2)0.0409 (4)
H31.16480.94111.02150.049*
C41.0837 (2)0.86024 (7)0.9572 (2)0.0374 (4)
H41.14310.84521.07230.045*
C50.9828 (2)0.82576 (6)0.81912 (18)0.0281 (3)
H50.97260.78690.84040.034*
C60.89542 (19)0.84719 (6)0.64844 (18)0.0246 (3)
C70.79269 (19)0.81097 (6)0.49710 (18)0.0246 (3)
C80.56322 (19)0.68201 (6)0.42645 (18)0.0242 (3)
H80.562 (2)0.6739 (7)0.542 (2)0.029*
C90.47973 (19)0.64095 (6)0.28383 (17)0.0252 (3)
C100.5196 (2)0.58369 (6)0.31608 (19)0.0286 (3)
C110.4494 (2)0.54288 (7)0.1881 (2)0.0379 (4)
H110.48070.50450.21450.045*
C120.3331 (3)0.55883 (8)0.0214 (2)0.0439 (4)
H120.28490.53130.06810.053*
C130.2862 (2)0.61464 (8)0.0162 (2)0.0406 (4)
H130.20480.62540.13070.049*
C140.3588 (2)0.65488 (6)0.11426 (19)0.0297 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0478 (2)0.02692 (19)0.0405 (2)0.00367 (16)0.00954 (17)0.00623 (15)
Cl20.03272 (19)0.0378 (2)0.0399 (2)0.00243 (15)0.00277 (15)0.01388 (16)
O10.0530 (7)0.0320 (6)0.0225 (5)0.0099 (5)0.0088 (5)0.0033 (4)
O20.0526 (7)0.0255 (5)0.0402 (7)0.0026 (5)0.0013 (5)0.0067 (5)
N10.0302 (6)0.0239 (6)0.0174 (5)0.0030 (4)0.0079 (5)0.0014 (4)
N20.0253 (5)0.0229 (5)0.0214 (5)0.0000 (4)0.0077 (4)0.0026 (4)
C10.0309 (7)0.0255 (7)0.0350 (8)0.0002 (5)0.0097 (6)0.0000 (6)
C20.0373 (8)0.0269 (7)0.0494 (9)0.0047 (6)0.0130 (7)0.0102 (7)
C30.0394 (8)0.0431 (9)0.0382 (9)0.0097 (7)0.0104 (7)0.0166 (7)
C40.0375 (8)0.0470 (9)0.0261 (7)0.0070 (7)0.0088 (6)0.0059 (6)
C50.0273 (7)0.0315 (7)0.0257 (7)0.0033 (5)0.0092 (6)0.0009 (5)
C60.0237 (6)0.0254 (7)0.0249 (7)0.0003 (5)0.0084 (5)0.0026 (5)
C70.0269 (7)0.0229 (6)0.0232 (7)0.0022 (5)0.0076 (5)0.0011 (5)
C80.0274 (7)0.0229 (6)0.0225 (7)0.0012 (5)0.0087 (5)0.0011 (5)
C90.0272 (6)0.0257 (7)0.0250 (7)0.0032 (5)0.0118 (5)0.0010 (5)
C100.0310 (7)0.0272 (7)0.0305 (7)0.0025 (6)0.0142 (6)0.0012 (5)
C110.0469 (9)0.0279 (7)0.0450 (9)0.0067 (6)0.0238 (8)0.0096 (7)
C120.0539 (10)0.0437 (10)0.0386 (9)0.0164 (8)0.0214 (8)0.0176 (7)
C130.0431 (9)0.0520 (10)0.0255 (7)0.0143 (8)0.0102 (7)0.0048 (7)
C140.0299 (7)0.0324 (7)0.0279 (7)0.0058 (6)0.0114 (6)0.0022 (6)
Geometric parameters (Å, º) top
Cl1—C101.7395 (15)C4—H40.9500
Cl2—C141.7364 (16)C5—C61.399 (2)
O1—C71.2448 (17)C5—H50.9500
O2—C11.3582 (19)C6—C71.4763 (18)
O2—H2A0.90 (2)C8—C91.4745 (19)
N1—C71.3533 (18)C8—H80.954 (17)
N1—N21.3788 (15)C9—C141.396 (2)
N1—H10.854 (18)C9—C101.402 (2)
N2—C81.2761 (18)C10—C111.383 (2)
C1—C21.395 (2)C11—C121.379 (3)
C1—C61.406 (2)C11—H110.9500
C2—C31.378 (2)C12—C131.383 (3)
C2—H20.9500C12—H120.9500
C3—C41.390 (3)C13—C141.388 (2)
C3—H30.9500C13—H130.9500
C4—C51.381 (2)
C1—O2—H2A103.3 (15)O1—C7—C6121.12 (12)
C7—N1—N2117.32 (11)N1—C7—C6117.68 (12)
C7—N1—H1121.9 (11)N2—C8—C9118.97 (12)
N2—N1—H1120.5 (11)N2—C8—H8122.3 (10)
C8—N2—N1116.20 (11)C9—C8—H8118.7 (10)
O2—C1—C2117.72 (14)C14—C9—C10116.02 (13)
O2—C1—C6122.16 (13)C14—C9—C8124.31 (13)
C2—C1—C6120.12 (14)C10—C9—C8119.67 (12)
C3—C2—C1119.77 (15)C11—C10—C9122.96 (15)
C3—C2—H2120.1C11—C10—Cl1117.91 (12)
C1—C2—H2120.1C9—C10—Cl1119.14 (11)
C2—C3—C4120.96 (15)C12—C11—C10118.86 (15)
C2—C3—H3119.5C12—C11—H11120.6
C4—C3—H3119.5C10—C11—H11120.6
C5—C4—C3119.43 (15)C11—C12—C13120.47 (15)
C5—C4—H4120.3C11—C12—H12119.8
C3—C4—H4120.3C13—C12—H12119.8
C4—C5—C6121.02 (14)C12—C13—C14119.64 (16)
C4—C5—H5119.5C12—C13—H13120.2
C6—C5—H5119.5C14—C13—H13120.2
C5—C6—C1118.64 (13)C13—C14—C9122.02 (15)
C5—C6—C7122.17 (12)C13—C14—Cl2117.22 (12)
C1—C6—C7119.07 (12)C9—C14—Cl2120.70 (11)
O1—C7—N1121.20 (12)
C7—N1—N2—C8175.33 (12)N1—N2—C8—C9177.11 (11)
O2—C1—C2—C3177.58 (15)N2—C8—C9—C1447.26 (19)
C6—C1—C2—C31.9 (2)N2—C8—C9—C10133.40 (14)
C1—C2—C3—C40.1 (2)C14—C9—C10—C111.8 (2)
C2—C3—C4—C51.3 (2)C8—C9—C10—C11178.78 (13)
C3—C4—C5—C60.4 (2)C14—C9—C10—Cl1178.18 (10)
C4—C5—C6—C11.6 (2)C8—C9—C10—Cl11.21 (18)
C4—C5—C6—C7177.71 (13)C9—C10—C11—C120.7 (2)
O2—C1—C6—C5176.71 (13)Cl1—C10—C11—C12179.27 (12)
C2—C1—C6—C52.8 (2)C10—C11—C12—C130.6 (2)
O2—C1—C6—C70.5 (2)C11—C12—C13—C140.8 (2)
C2—C1—C6—C7178.98 (13)C12—C13—C14—C90.4 (2)
N2—N1—C7—O14.02 (19)C12—C13—C14—Cl2176.77 (13)
N2—N1—C7—C6175.26 (11)C10—C9—C14—C131.6 (2)
C5—C6—C7—O1155.05 (14)C8—C9—C14—C13179.01 (14)
C1—C6—C7—O121.0 (2)C10—C9—C14—Cl2175.41 (10)
C5—C6—C7—N124.23 (19)C8—C9—C14—Cl23.95 (19)
C1—C6—C7—N1159.71 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···N2i0.85 (2)2.38 (2)3.165 (2)153 (2)
N1—H1···O1i0.85 (2)2.45 (2)3.158 (2)140 (1)
O2—H2A···O10.90 (2)1.78 (2)2.608 (2)153 (2)
Symmetry code: (i) x, y+3/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC14H10Cl2N2O2
Mr309.14
Crystal system, space groupMonoclinic, P21/c
Temperature (K)180
a, b, c (Å)7.5029 (6), 23.8363 (13), 8.0286 (7)
β (°) 109.860 (6)
V3)1350.45 (18)
Z4
Radiation typeMo Kα
µ (mm1)0.48
Crystal size (mm)0.34 × 0.26 × 0.18
Data collection
DiffractometerStoe IPDS2T
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2007)
Tmin, Tmax0.856, 0.921
No. of measured, independent and
observed [I > 2σ(I)] reflections
21101, 2958, 2455
Rint0.041
(sin θ/λ)max1)0.639
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.029, 0.074, 1.03
No. of reflections2958
No. of parameters191
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.24, 0.39

Computer programs: X-AREA (Stoe & Cie, 1999), 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···N2i0.85 (2)2.38 (2)3.165 (2)153 (2)
N1—H1···O1i0.85 (2)2.45 (2)3.158 (2)140 (1)
O2—H2A···O10.90 (2)1.78 (2)2.608 (2)153 (2)
Symmetry code: (i) x, y+3/2, z+1/2.
 

Acknowledgements

HLS is grateful to the Institute of Chemistry, University of the Punjab, for financial support.

References

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