organic compounds
2-[(E)-(3-Carboxy-4-hydroxyphenyl)iminiomethyl]-4-chlorophenolate
aSchool of Chemical Sciences, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: hkfun@usm.my
The title Schiff base compound, C14H10ClNO4, has been synthesized by the reaction of 5-amino-2-hydroxybenzoic acid and 5-chloro-2-hydroxybenzaldehyde. The molecule is a zwitterion in the crystal, with the phenolic hydroxy group deprotonated and the imine N atom protonated. It adopts an E configuration about the central C=N double bond. The dihedral angle between the two benzene rings is 3.83 (7)°. Intramolecular N—H⋯O and O—H⋯O hydrogen bonding generates S(6) ring motifs. In the crystal, molecules are connected by intermolecular O—H⋯O and C—H⋯Cl hydrogen bonds, forming a supramolecular chain.
Related literature
For applications of et al. (2009); Salih & Hamdi (2008); Belaid et al. (2006); Karthikeyan et al. (2006). For hydrogen-bond motifs, see: Bernstein et al. (1995). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).
see: YoussefExperimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009).
Supporting information
https://doi.org/10.1107/S1600536810033362/fj2328sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810033362/fj2328Isup2.hkl
To a stirred solution of 5-amino -2- hydroxybenzoic acid (0.40 g, 2.9 mmol) in methanol was added 5-chloro-2-hydroxybenzaldehyde (0.40 g, 2.5 mmol). The reaction was refluxed for 1 h at 70°C after which the precipitate formed was filtered and recrystallized from dichloromethane and methanol (1:1). Orange needle-shaped single crystals suitable for X-ray
were formed after slow evaporation of solvent at room temperature.Atoms H1N1 and H1O1 were located from a difference Fourier map and were refined freely [N–H= 0.85 (2) Å and O–H= 0.96 (3) Å]. The remaining hydrogen atoms were positioned geometrically [C–H = 0.93 Å] and were refined using a riding model, with Uiso(H) = 1.2 or 1.5 Ueq(C, O).
Schiff bases have received much attention, mainly because of their extensive application in the field of synthesis and catalysis (Youssef et al., 2009; Salih & Hamdi, 2008).
derived from ortho-phenylenediamine are of particular interests because of the proximity of the nitrogen atoms, which permits their simultaneous coordination to the same metal cation, leading to more stable compounds (Belaid et al., 2006). Schiff base ligands are an important class of compounds, possessing a wide spectrum of biological and pharmacological activities such as antibacterial and antifungal (Karthikeyan et al., 2006) properties. Keeping in view of the importance of the the title compound (I) was synthesized.The molecule of (I), (Fig. 1), crystallizes in a zwitterionic form with cationic iminium and anionic phenolate i.e. the phenol -OH group was deprotonated and the imine N atom was protonated. (I) exists in a trans configuration about the C7═N1 bond [1.3061 (19) Å] with the torsion angle C6-C7-N1-C8 = 178.05 (13)°. The dihedral angle between the two phenyl (C1–C6)/(C8–C13) rings is 3.83 (7)°.
In the
(Fig. 2), intramolecular N1—H1N1···O4 and O1—H1O1···O2 hydrogen bonding generates an S(6) ring motifs (Bernstein et al., 1995). The is further stabilized by intermolecular O3—H1O3···O4 and C7—H7A···Cl1 (Table 1) hydrogen bonds, to form one-dimensional chains.For applications of
see: Youssef et al. (2009); Salih & Hamdi (2008); Belaid et al. (2006); Karthikeyan et al. (2006). For hydrogen-bond motifs, see: Bernstein et al. (1995). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).C14H10ClNO4 | F(000) = 600 |
Mr = 291.68 | Dx = 1.589 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 5212 reflections |
a = 7.1504 (6) Å | θ = 2.9–29.8° |
b = 10.9059 (10) Å | µ = 0.33 mm−1 |
c = 15.8015 (18) Å | T = 100 K |
β = 98.396 (2)° | Needle, orange |
V = 1219.0 (2) Å3 | 0.36 × 0.08 × 0.05 mm |
Z = 4 |
Bruker APEXII DUO CCD area-detector diffractometer | 3548 independent reflections |
Radiation source: fine-focus sealed tube | 2839 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.048 |
φ and ω scans | θmax = 30.0°, θmin = 2.3° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −10→10 |
Tmin = 0.892, Tmax = 0.984 | k = −15→15 |
24711 measured reflections | l = −21→22 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.038 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.111 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0527P)2 + 0.5702P] where P = (Fo2 + 2Fc2)/3 |
3548 reflections | (Δ/σ)max = 0.001 |
189 parameters | Δρmax = 0.33 e Å−3 |
0 restraints | Δρmin = −0.26 e Å−3 |
C14H10ClNO4 | V = 1219.0 (2) Å3 |
Mr = 291.68 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.1504 (6) Å | µ = 0.33 mm−1 |
b = 10.9059 (10) Å | T = 100 K |
c = 15.8015 (18) Å | 0.36 × 0.08 × 0.05 mm |
β = 98.396 (2)° |
Bruker APEXII DUO CCD area-detector diffractometer | 3548 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 2839 reflections with I > 2σ(I) |
Tmin = 0.892, Tmax = 0.984 | Rint = 0.048 |
24711 measured reflections |
R[F2 > 2σ(F2)] = 0.038 | 0 restraints |
wR(F2) = 0.111 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.33 e Å−3 |
3548 reflections | Δρmin = −0.26 e Å−3 |
189 parameters |
Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K. |
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 | 0.12582 (5) | 0.88201 (4) | −0.28298 (2) | 0.02899 (12) | |
O1 | 0.20080 (17) | 0.01744 (10) | 0.13325 (8) | 0.0279 (3) | |
O2 | 0.37683 (16) | 0.09144 (10) | 0.27923 (7) | 0.0273 (3) | |
O3 | 0.44612 (16) | 0.29081 (10) | 0.29829 (7) | 0.0267 (3) | |
H1O3 | 0.5054 | 0.2615 | 0.3536 | 0.040* | |
O4 | 0.38530 (16) | 0.70448 (10) | 0.06318 (7) | 0.0259 (2) | |
N1 | 0.26920 (16) | 0.49306 (11) | 0.01711 (8) | 0.0191 (2) | |
C1 | 0.3279 (2) | 0.74509 (13) | −0.01393 (9) | 0.0195 (3) | |
C2 | 0.3424 (2) | 0.86975 (14) | −0.03574 (10) | 0.0217 (3) | |
H2A | 0.3936 | 0.9254 | 0.0059 | 0.026* | |
C3 | 0.2821 (2) | 0.91040 (14) | −0.11739 (10) | 0.0218 (3) | |
H3A | 0.2931 | 0.9929 | −0.1308 | 0.026* | |
C4 | 0.20390 (19) | 0.82731 (14) | −0.18053 (9) | 0.0203 (3) | |
C5 | 0.18541 (19) | 0.70552 (14) | −0.16270 (9) | 0.0194 (3) | |
H5A | 0.1326 | 0.6517 | −0.2053 | 0.023* | |
C6 | 0.24713 (18) | 0.66229 (13) | −0.07925 (9) | 0.0173 (3) | |
C7 | 0.22361 (19) | 0.53618 (13) | −0.06027 (9) | 0.0190 (3) | |
H7A | 0.1746 | 0.4832 | −0.1040 | 0.023* | |
C8 | 0.24807 (19) | 0.37125 (13) | 0.04491 (9) | 0.0187 (3) | |
C9 | 0.1617 (2) | 0.27914 (13) | −0.00918 (9) | 0.0208 (3) | |
H9A | 0.1156 | 0.2968 | −0.0660 | 0.025* | |
C10 | 0.1456 (2) | 0.16216 (14) | 0.02226 (10) | 0.0222 (3) | |
H10A | 0.0870 | 0.1013 | −0.0134 | 0.027* | |
C11 | 0.2162 (2) | 0.13432 (13) | 0.10694 (10) | 0.0209 (3) | |
C12 | 0.30148 (19) | 0.22675 (13) | 0.16180 (9) | 0.0194 (3) | |
C13 | 0.31643 (19) | 0.34519 (13) | 0.12975 (9) | 0.0186 (3) | |
H13A | 0.3725 | 0.4068 | 0.1654 | 0.022* | |
C14 | 0.3777 (2) | 0.19733 (14) | 0.25151 (10) | 0.0217 (3) | |
H1N1 | 0.322 (3) | 0.5468 (19) | 0.0518 (13) | 0.029 (5)* | |
H1O1 | 0.268 (3) | 0.024 (2) | 0.1903 (16) | 0.052 (7)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.02706 (19) | 0.0374 (2) | 0.02110 (19) | 0.00013 (15) | −0.00132 (13) | 0.00998 (15) |
O1 | 0.0366 (6) | 0.0206 (5) | 0.0258 (6) | −0.0036 (4) | 0.0025 (5) | 0.0019 (4) |
O2 | 0.0324 (6) | 0.0254 (6) | 0.0238 (6) | −0.0010 (4) | 0.0030 (5) | 0.0057 (4) |
O3 | 0.0361 (6) | 0.0245 (5) | 0.0177 (5) | 0.0030 (4) | −0.0028 (4) | −0.0001 (4) |
O4 | 0.0354 (6) | 0.0273 (5) | 0.0138 (5) | −0.0058 (4) | −0.0012 (4) | 0.0009 (4) |
N1 | 0.0199 (5) | 0.0197 (6) | 0.0175 (6) | −0.0016 (4) | 0.0018 (4) | −0.0005 (5) |
C1 | 0.0199 (6) | 0.0228 (7) | 0.0161 (6) | −0.0013 (5) | 0.0036 (5) | −0.0005 (5) |
C2 | 0.0230 (6) | 0.0214 (7) | 0.0209 (7) | −0.0046 (5) | 0.0038 (5) | −0.0012 (5) |
C3 | 0.0205 (6) | 0.0216 (7) | 0.0241 (7) | −0.0014 (5) | 0.0058 (5) | 0.0019 (5) |
C4 | 0.0174 (6) | 0.0252 (7) | 0.0182 (7) | 0.0017 (5) | 0.0026 (5) | 0.0047 (5) |
C5 | 0.0169 (6) | 0.0249 (7) | 0.0165 (7) | −0.0011 (5) | 0.0024 (5) | −0.0006 (5) |
C6 | 0.0163 (6) | 0.0198 (6) | 0.0165 (6) | −0.0007 (5) | 0.0043 (5) | −0.0001 (5) |
C7 | 0.0176 (6) | 0.0218 (6) | 0.0177 (7) | −0.0003 (5) | 0.0029 (5) | −0.0013 (5) |
C8 | 0.0172 (6) | 0.0204 (6) | 0.0188 (7) | 0.0019 (5) | 0.0038 (5) | 0.0011 (5) |
C9 | 0.0209 (6) | 0.0223 (7) | 0.0184 (7) | 0.0005 (5) | 0.0002 (5) | −0.0010 (5) |
C10 | 0.0217 (6) | 0.0208 (7) | 0.0234 (7) | −0.0011 (5) | 0.0015 (5) | −0.0037 (5) |
C11 | 0.0198 (6) | 0.0213 (7) | 0.0222 (7) | −0.0005 (5) | 0.0045 (5) | −0.0004 (5) |
C12 | 0.0175 (6) | 0.0227 (7) | 0.0186 (7) | 0.0018 (5) | 0.0043 (5) | −0.0005 (5) |
C13 | 0.0178 (6) | 0.0208 (6) | 0.0174 (7) | 0.0003 (5) | 0.0032 (5) | −0.0018 (5) |
C14 | 0.0208 (6) | 0.0251 (7) | 0.0197 (7) | 0.0025 (5) | 0.0047 (5) | 0.0010 (5) |
Cl1—C4 | 1.7390 (15) | C4—C5 | 1.368 (2) |
O1—C11 | 1.3502 (18) | C5—C6 | 1.4093 (19) |
O1—H1O1 | 0.96 (3) | C5—H5A | 0.9300 |
O2—C14 | 1.2355 (19) | C6—C7 | 1.423 (2) |
O3—C14 | 1.3113 (19) | C7—H7A | 0.9300 |
O3—H1O3 | 0.9687 | C8—C13 | 1.3876 (19) |
O4—C1 | 1.3051 (17) | C8—C9 | 1.402 (2) |
N1—C7 | 1.3061 (19) | C9—C10 | 1.380 (2) |
N1—C8 | 1.4143 (18) | C9—H9A | 0.9300 |
N1—H1N1 | 0.85 (2) | C10—C11 | 1.393 (2) |
C1—C2 | 1.410 (2) | C10—H10A | 0.9300 |
C1—C6 | 1.4284 (19) | C11—C12 | 1.409 (2) |
C2—C3 | 1.373 (2) | C12—C13 | 1.397 (2) |
C2—H2A | 0.9300 | C12—C14 | 1.478 (2) |
C3—C4 | 1.402 (2) | C13—H13A | 0.9300 |
C3—H3A | 0.9300 | ||
C11—O1—H1O1 | 99.8 (15) | N1—C7—H7A | 119.2 |
C14—O3—H1O3 | 109.3 | C6—C7—H7A | 119.2 |
C7—N1—C8 | 127.27 (13) | C13—C8—C9 | 120.25 (13) |
C7—N1—H1N1 | 112.4 (14) | C13—C8—N1 | 117.00 (13) |
C8—N1—H1N1 | 120.2 (14) | C9—C8—N1 | 122.76 (13) |
O4—C1—C2 | 122.09 (13) | C10—C9—C8 | 119.69 (14) |
O4—C1—C6 | 119.93 (13) | C10—C9—H9A | 120.2 |
C2—C1—C6 | 117.99 (13) | C8—C9—H9A | 120.2 |
C3—C2—C1 | 121.13 (14) | C9—C10—C11 | 120.64 (14) |
C3—C2—H2A | 119.4 | C9—C10—H10A | 119.7 |
C1—C2—H2A | 119.4 | C11—C10—H10A | 119.7 |
C2—C3—C4 | 119.86 (14) | O1—C11—C10 | 117.85 (13) |
C2—C3—H3A | 120.1 | O1—C11—C12 | 122.24 (14) |
C4—C3—H3A | 120.1 | C10—C11—C12 | 119.91 (14) |
C5—C4—C3 | 121.42 (14) | C13—C12—C11 | 119.18 (13) |
C5—C4—Cl1 | 119.81 (12) | C13—C12—C14 | 120.76 (13) |
C3—C4—Cl1 | 118.76 (11) | C11—C12—C14 | 120.04 (13) |
C4—C5—C6 | 119.40 (13) | C8—C13—C12 | 120.31 (13) |
C4—C5—H5A | 120.3 | C8—C13—H13A | 119.8 |
C6—C5—H5A | 120.3 | C12—C13—H13A | 119.8 |
C5—C6—C7 | 119.34 (13) | O2—C14—O3 | 123.20 (14) |
C5—C6—C1 | 120.20 (13) | O2—C14—C12 | 121.53 (14) |
C7—C6—C1 | 120.44 (13) | O3—C14—C12 | 115.27 (13) |
N1—C7—C6 | 121.62 (13) | ||
O4—C1—C2—C3 | 179.64 (13) | C13—C8—C9—C10 | −0.2 (2) |
C6—C1—C2—C3 | −0.5 (2) | N1—C8—C9—C10 | −179.90 (13) |
C1—C2—C3—C4 | 0.3 (2) | C8—C9—C10—C11 | −0.8 (2) |
C2—C3—C4—C5 | 0.2 (2) | C9—C10—C11—O1 | −178.20 (13) |
C2—C3—C4—Cl1 | 179.12 (11) | C9—C10—C11—C12 | 1.4 (2) |
C3—C4—C5—C6 | −0.4 (2) | O1—C11—C12—C13 | 178.57 (13) |
Cl1—C4—C5—C6 | −179.28 (10) | C10—C11—C12—C13 | −1.0 (2) |
C4—C5—C6—C7 | 178.48 (13) | O1—C11—C12—C14 | −0.1 (2) |
C4—C5—C6—C1 | 0.1 (2) | C10—C11—C12—C14 | −179.59 (13) |
O4—C1—C6—C5 | −179.82 (13) | C9—C8—C13—C12 | 0.6 (2) |
C2—C1—C6—C5 | 0.3 (2) | N1—C8—C13—C12 | −179.70 (12) |
O4—C1—C6—C7 | 1.8 (2) | C11—C12—C13—C8 | 0.0 (2) |
C2—C1—C6—C7 | −178.04 (13) | C14—C12—C13—C8 | 178.60 (13) |
C8—N1—C7—C6 | 178.05 (13) | C13—C12—C14—O2 | −175.13 (14) |
C5—C6—C7—N1 | −176.28 (13) | C11—C12—C14—O2 | 3.5 (2) |
C1—C6—C7—N1 | 2.1 (2) | C13—C12—C14—O3 | 4.4 (2) |
C7—N1—C8—C13 | 176.56 (13) | C11—C12—C14—O3 | −176.96 (13) |
C7—N1—C8—C9 | −3.8 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H1O3···O4i | 0.97 | 1.56 | 2.5220 (16) | 173 |
N1—H1N1···O4 | 0.85 (2) | 1.78 (2) | 2.5217 (17) | 144.2 (19) |
O1—H1O1···O2 | 0.96 (2) | 1.67 (2) | 2.5901 (17) | 158 (2) |
C7—H7A···Cl1ii | 0.93 | 2.81 | 3.6603 (15) | 152 |
Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) −x, y−1/2, −z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C14H10ClNO4 |
Mr | 291.68 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 100 |
a, b, c (Å) | 7.1504 (6), 10.9059 (10), 15.8015 (18) |
β (°) | 98.396 (2) |
V (Å3) | 1219.0 (2) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.33 |
Crystal size (mm) | 0.36 × 0.08 × 0.05 |
Data collection | |
Diffractometer | Bruker APEXII DUO CCD area-detector |
Absorption correction | Multi-scan (SADABS; Bruker, 2009) |
Tmin, Tmax | 0.892, 0.984 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 24711, 3548, 2839 |
Rint | 0.048 |
(sin θ/λ)max (Å−1) | 0.704 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.038, 0.111, 1.03 |
No. of reflections | 3548 |
No. of parameters | 189 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.33, −0.26 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H1O3···O4i | 0.9700 | 1.5600 | 2.5220 (16) | 173.00 |
N1—H1N1···O4 | 0.85 (2) | 1.78 (2) | 2.5217 (17) | 144.2 (19) |
O1—H1O1···O2 | 0.96 (2) | 1.67 (2) | 2.5901 (17) | 158 (2) |
C7—H7A···Cl1ii | 0.9300 | 2.8100 | 3.6603 (15) | 152.00 |
Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) −x, y−1/2, −z−1/2. |
Acknowledgements
AMF, TSG and HO thank the Malaysian Government and Universiti Sains Malaysia for the RU research grant (1001/PKIMIA/815002). AMF thanks the Libyan Government for providing a scholarship. MH and HKF thank the Malaysian Government and Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012. MH also thanks Universiti Sains Malaysia for a post-doctoral research fellowship.
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Schiff bases have received much attention, mainly because of their extensive application in the field of synthesis and catalysis (Youssef et al., 2009; Salih & Hamdi, 2008). Schiff bases derived from ortho-phenylenediamine are of particular interests because of the proximity of the nitrogen atoms, which permits their simultaneous coordination to the same metal cation, leading to more stable compounds (Belaid et al., 2006). Schiff base ligands are an important class of compounds, possessing a wide spectrum of biological and pharmacological activities such as antibacterial and antifungal (Karthikeyan et al., 2006) properties. Keeping in view of the importance of the Schiff bases, the title compound (I) was synthesized.
The molecule of (I), (Fig. 1), crystallizes in a zwitterionic form with cationic iminium and anionic phenolate i.e. the phenol -OH group was deprotonated and the imine N atom was protonated. (I) exists in a trans configuration about the C7═N1 bond [1.3061 (19) Å] with the torsion angle C6-C7-N1-C8 = 178.05 (13)°. The dihedral angle between the two phenyl (C1–C6)/(C8–C13) rings is 3.83 (7)°.
In the crystal structure (Fig. 2), intramolecular N1—H1N1···O4 and O1—H1O1···O2 hydrogen bonding generates an S(6) ring motifs (Bernstein et al., 1995). The crystal structure is further stabilized by intermolecular O3—H1O3···O4 and C7—H7A···Cl1 (Table 1) hydrogen bonds, to form one-dimensional chains.