organic compounds
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
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 intermolecular N—H⋯O and O—H⋯O hydrogen-bonding interactions occur.
Related literature
For the biological activity of et al. (2000); Samadhiya & Halve (2001). For the synthesis of see: Siddiqui et al. (2006); Iqbal et al. (2007). For applications of see: Mookherjee et al. (1989); Kumar et al. (2009). For graph-set notation, see: Bernstein et al. (1995).
see: El-MasryExperimental
Crystal data
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Refinement
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Data collection: X-AREA (Stoe & Cie, 1999); cell X-AREA; data reduction: X-AREA; 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.
Supporting information
10.1107/S1600536810035385/im2223sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536810035385/im2223Isup2.hkl
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.
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.
Data collection: X-AREA (Stoe & Cie, 1999); cell
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).C14H10Cl2N2O2 | F(000) = 632 |
Mr = 309.14 | Dx = 1.520 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 19179 reflections |
a = 7.5029 (6) Å | θ = 1.7–29.5° |
b = 23.8363 (13) Å | µ = 0.48 mm−1 |
c = 8.0286 (7) Å | T = 180 K |
β = 109.860 (6)° | Needles, white |
V = 1350.45 (18) Å3 | 0.34 × 0.26 × 0.18 mm |
Z = 4 |
Stoe IPDS-2T diffractometer | 2958 independent reflections |
Radiation source: fine-focus sealed tube | 2455 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.041 |
ω scans | θmax = 27.0°, θmin = 1.7° |
Absorption correction: multi-scan (SADABS; Bruker, 2007) | h = −9→9 |
Tmin = 0.856, Tmax = 0.921 | k = −30→30 |
21101 measured reflections | l = −10→10 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.029 | H 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 reflections | Δρmax = 0.24 e Å−3 |
191 parameters | Δρmin = −0.39 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0085 (19) |
C14H10Cl2N2O2 | V = 1350.45 (18) Å3 |
Mr = 309.14 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.5029 (6) Å | µ = 0.48 mm−1 |
b = 23.8363 (13) Å | T = 180 K |
c = 8.0286 (7) Å | 0.34 × 0.26 × 0.18 mm |
β = 109.860 (6)° |
Stoe IPDS-2T diffractometer | 2958 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2007) | 2455 reflections with I > 2σ(I) |
Tmin = 0.856, Tmax = 0.921 | Rint = 0.041 |
21101 measured reflections |
R[F2 > 2σ(F2)] = 0.029 | 0 restraints |
wR(F2) = 0.074 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.24 e Å−3 |
2958 reflections | Δρmin = −0.39 e Å−3 |
191 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
Cl1 | 0.66364 (6) | 0.562338 (15) | 0.52580 (5) | 0.03982 (12) | |
Cl2 | 0.28455 (5) | 0.723630 (17) | 0.06158 (5) | 0.03924 (12) | |
O1 | 0.77275 (17) | 0.82495 (4) | 0.34242 (14) | 0.0369 (3) | |
O2 | 0.84369 (18) | 0.92793 (5) | 0.45517 (16) | 0.0431 (3) | |
H2A | 0.809 (3) | 0.8981 (10) | 0.383 (3) | 0.065* | |
N1 | 0.72285 (16) | 0.76179 (5) | 0.53258 (15) | 0.0239 (2) | |
H1 | 0.720 (2) | 0.7541 (7) | 0.636 (2) | 0.029* | |
N2 | 0.63961 (16) | 0.72631 (5) | 0.39193 (15) | 0.0233 (2) | |
C1 | 0.9163 (2) | 0.90454 (6) | 0.6187 (2) | 0.0308 (3) | |
C2 | 1.0154 (2) | 0.93943 (7) | 0.7591 (2) | 0.0383 (4) | |
H2 | 1.0262 | 0.9784 | 0.7396 | 0.046* | |
C3 | 1.0976 (2) | 0.91717 (7) | 0.9261 (2) | 0.0409 (4) | |
H3 | 1.1648 | 0.9411 | 1.0215 | 0.049* | |
C4 | 1.0837 (2) | 0.86024 (7) | 0.9572 (2) | 0.0374 (4) | |
H4 | 1.1431 | 0.8452 | 1.0723 | 0.045* | |
C5 | 0.9828 (2) | 0.82576 (6) | 0.81912 (18) | 0.0281 (3) | |
H5 | 0.9726 | 0.7869 | 0.8404 | 0.034* | |
C6 | 0.89542 (19) | 0.84719 (6) | 0.64844 (18) | 0.0246 (3) | |
C7 | 0.79269 (19) | 0.81097 (6) | 0.49710 (18) | 0.0246 (3) | |
C8 | 0.56322 (19) | 0.68201 (6) | 0.42645 (18) | 0.0242 (3) | |
H8 | 0.562 (2) | 0.6739 (7) | 0.542 (2) | 0.029* | |
C9 | 0.47973 (19) | 0.64095 (6) | 0.28383 (17) | 0.0252 (3) | |
C10 | 0.5196 (2) | 0.58369 (6) | 0.31608 (19) | 0.0286 (3) | |
C11 | 0.4494 (2) | 0.54288 (7) | 0.1881 (2) | 0.0379 (4) | |
H11 | 0.4807 | 0.5045 | 0.2145 | 0.045* | |
C12 | 0.3331 (3) | 0.55883 (8) | 0.0214 (2) | 0.0439 (4) | |
H12 | 0.2849 | 0.5313 | −0.0681 | 0.053* | |
C13 | 0.2862 (2) | 0.61464 (8) | −0.0162 (2) | 0.0406 (4) | |
H13 | 0.2048 | 0.6254 | −0.1307 | 0.049* | |
C14 | 0.3588 (2) | 0.65488 (6) | 0.11426 (19) | 0.0297 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0478 (2) | 0.02692 (19) | 0.0405 (2) | 0.00367 (16) | 0.00954 (17) | 0.00623 (15) |
Cl2 | 0.03272 (19) | 0.0378 (2) | 0.0399 (2) | −0.00243 (15) | 0.00277 (15) | 0.01388 (16) |
O1 | 0.0530 (7) | 0.0320 (6) | 0.0225 (5) | −0.0099 (5) | 0.0088 (5) | 0.0033 (4) |
O2 | 0.0526 (7) | 0.0255 (5) | 0.0402 (7) | −0.0026 (5) | 0.0013 (5) | 0.0067 (5) |
N1 | 0.0302 (6) | 0.0239 (6) | 0.0174 (5) | −0.0030 (4) | 0.0079 (5) | −0.0014 (4) |
N2 | 0.0253 (5) | 0.0229 (5) | 0.0214 (5) | 0.0000 (4) | 0.0077 (4) | −0.0026 (4) |
C1 | 0.0309 (7) | 0.0255 (7) | 0.0350 (8) | 0.0002 (5) | 0.0097 (6) | 0.0000 (6) |
C2 | 0.0373 (8) | 0.0269 (7) | 0.0494 (9) | −0.0047 (6) | 0.0130 (7) | −0.0102 (7) |
C3 | 0.0394 (8) | 0.0431 (9) | 0.0382 (9) | −0.0097 (7) | 0.0104 (7) | −0.0166 (7) |
C4 | 0.0375 (8) | 0.0470 (9) | 0.0261 (7) | −0.0070 (7) | 0.0088 (6) | −0.0059 (6) |
C5 | 0.0273 (7) | 0.0315 (7) | 0.0257 (7) | −0.0033 (5) | 0.0092 (6) | −0.0009 (5) |
C6 | 0.0237 (6) | 0.0254 (7) | 0.0249 (7) | −0.0003 (5) | 0.0084 (5) | −0.0026 (5) |
C7 | 0.0269 (7) | 0.0229 (6) | 0.0232 (7) | 0.0022 (5) | 0.0076 (5) | 0.0011 (5) |
C8 | 0.0274 (7) | 0.0229 (6) | 0.0225 (7) | 0.0012 (5) | 0.0087 (5) | 0.0011 (5) |
C9 | 0.0272 (6) | 0.0257 (7) | 0.0250 (7) | −0.0032 (5) | 0.0118 (5) | −0.0010 (5) |
C10 | 0.0310 (7) | 0.0272 (7) | 0.0305 (7) | −0.0025 (6) | 0.0142 (6) | −0.0012 (5) |
C11 | 0.0469 (9) | 0.0279 (7) | 0.0450 (9) | −0.0067 (6) | 0.0238 (8) | −0.0096 (7) |
C12 | 0.0539 (10) | 0.0437 (10) | 0.0386 (9) | −0.0164 (8) | 0.0214 (8) | −0.0176 (7) |
C13 | 0.0431 (9) | 0.0520 (10) | 0.0255 (7) | −0.0143 (8) | 0.0102 (7) | −0.0048 (7) |
C14 | 0.0299 (7) | 0.0324 (7) | 0.0279 (7) | −0.0058 (6) | 0.0114 (6) | 0.0022 (6) |
Cl1—C10 | 1.7395 (15) | C4—H4 | 0.9500 |
Cl2—C14 | 1.7364 (16) | C5—C6 | 1.399 (2) |
O1—C7 | 1.2448 (17) | C5—H5 | 0.9500 |
O2—C1 | 1.3582 (19) | C6—C7 | 1.4763 (18) |
O2—H2A | 0.90 (2) | C8—C9 | 1.4745 (19) |
N1—C7 | 1.3533 (18) | C8—H8 | 0.954 (17) |
N1—N2 | 1.3788 (15) | C9—C14 | 1.396 (2) |
N1—H1 | 0.854 (18) | C9—C10 | 1.402 (2) |
N2—C8 | 1.2761 (18) | C10—C11 | 1.383 (2) |
C1—C2 | 1.395 (2) | C11—C12 | 1.379 (3) |
C1—C6 | 1.406 (2) | C11—H11 | 0.9500 |
C2—C3 | 1.378 (2) | C12—C13 | 1.383 (3) |
C2—H2 | 0.9500 | C12—H12 | 0.9500 |
C3—C4 | 1.390 (3) | C13—C14 | 1.388 (2) |
C3—H3 | 0.9500 | C13—H13 | 0.9500 |
C4—C5 | 1.381 (2) | ||
C1—O2—H2A | 103.3 (15) | O1—C7—C6 | 121.12 (12) |
C7—N1—N2 | 117.32 (11) | N1—C7—C6 | 117.68 (12) |
C7—N1—H1 | 121.9 (11) | N2—C8—C9 | 118.97 (12) |
N2—N1—H1 | 120.5 (11) | N2—C8—H8 | 122.3 (10) |
C8—N2—N1 | 116.20 (11) | C9—C8—H8 | 118.7 (10) |
O2—C1—C2 | 117.72 (14) | C14—C9—C10 | 116.02 (13) |
O2—C1—C6 | 122.16 (13) | C14—C9—C8 | 124.31 (13) |
C2—C1—C6 | 120.12 (14) | C10—C9—C8 | 119.67 (12) |
C3—C2—C1 | 119.77 (15) | C11—C10—C9 | 122.96 (15) |
C3—C2—H2 | 120.1 | C11—C10—Cl1 | 117.91 (12) |
C1—C2—H2 | 120.1 | C9—C10—Cl1 | 119.14 (11) |
C2—C3—C4 | 120.96 (15) | C12—C11—C10 | 118.86 (15) |
C2—C3—H3 | 119.5 | C12—C11—H11 | 120.6 |
C4—C3—H3 | 119.5 | C10—C11—H11 | 120.6 |
C5—C4—C3 | 119.43 (15) | C11—C12—C13 | 120.47 (15) |
C5—C4—H4 | 120.3 | C11—C12—H12 | 119.8 |
C3—C4—H4 | 120.3 | C13—C12—H12 | 119.8 |
C4—C5—C6 | 121.02 (14) | C12—C13—C14 | 119.64 (16) |
C4—C5—H5 | 119.5 | C12—C13—H13 | 120.2 |
C6—C5—H5 | 119.5 | C14—C13—H13 | 120.2 |
C5—C6—C1 | 118.64 (13) | C13—C14—C9 | 122.02 (15) |
C5—C6—C7 | 122.17 (12) | C13—C14—Cl2 | 117.22 (12) |
C1—C6—C7 | 119.07 (12) | C9—C14—Cl2 | 120.70 (11) |
O1—C7—N1 | 121.20 (12) | ||
C7—N1—N2—C8 | −175.33 (12) | N1—N2—C8—C9 | −177.11 (11) |
O2—C1—C2—C3 | −177.58 (15) | N2—C8—C9—C14 | −47.26 (19) |
C6—C1—C2—C3 | 1.9 (2) | N2—C8—C9—C10 | 133.40 (14) |
C1—C2—C3—C4 | 0.1 (2) | C14—C9—C10—C11 | 1.8 (2) |
C2—C3—C4—C5 | −1.3 (2) | C8—C9—C10—C11 | −178.78 (13) |
C3—C4—C5—C6 | 0.4 (2) | C14—C9—C10—Cl1 | −178.18 (10) |
C4—C5—C6—C1 | 1.6 (2) | C8—C9—C10—Cl1 | 1.21 (18) |
C4—C5—C6—C7 | 177.71 (13) | C9—C10—C11—C12 | −0.7 (2) |
O2—C1—C6—C5 | 176.71 (13) | Cl1—C10—C11—C12 | 179.27 (12) |
C2—C1—C6—C5 | −2.8 (2) | C10—C11—C12—C13 | −0.6 (2) |
O2—C1—C6—C7 | 0.5 (2) | C11—C12—C13—C14 | 0.8 (2) |
C2—C1—C6—C7 | −178.98 (13) | C12—C13—C14—C9 | 0.4 (2) |
N2—N1—C7—O1 | 4.02 (19) | C12—C13—C14—Cl2 | −176.77 (13) |
N2—N1—C7—C6 | −175.26 (11) | C10—C9—C14—C13 | −1.6 (2) |
C5—C6—C7—O1 | −155.05 (14) | C8—C9—C14—C13 | 179.01 (14) |
C1—C6—C7—O1 | 21.0 (2) | C10—C9—C14—Cl2 | 175.41 (10) |
C5—C6—C7—N1 | 24.23 (19) | C8—C9—C14—Cl2 | −3.95 (19) |
C1—C6—C7—N1 | −159.71 (13) |
D—H···A | D—H | H···A | D···A | 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+3/2, z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C14H10Cl2N2O2 |
Mr | 309.14 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 180 |
a, b, c (Å) | 7.5029 (6), 23.8363 (13), 8.0286 (7) |
β (°) | 109.860 (6) |
V (Å3) | 1350.45 (18) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.48 |
Crystal size (mm) | 0.34 × 0.26 × 0.18 |
Data collection | |
Diffractometer | Stoe IPDS2T diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2007) |
Tmin, Tmax | 0.856, 0.921 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 21101, 2958, 2455 |
Rint | 0.041 |
(sin θ/λ)max (Å−1) | 0.639 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.029, 0.074, 1.03 |
No. of reflections | 2958 |
No. of parameters | 191 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 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).
D—H···A | D—H | H···A | D···A | 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+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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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).