organic compounds
(Z)-6-[(5-Chloro-2-hydroxyanilino)methylene]-4-methoxycyclohexa-2,4-dienone 0.25-hydrate
aDepartment of Physics, Ondokuz Mayıs University, TR-55139 Samsun, Turkey, bFaculty of Education, Sinop University, Turkey, and cPamukkale University, Denizli Technical Vocational School, Turkey
*Correspondence e-mail: orhanb@omu.edu.tr
The title compound, C14H12ClNO3·0.25H2O, exists in the keto–amine form, and the aromatic rings are oriented at a dihedral angle of 7.24 (7)°. Bifurcated intramolecular N—H⋯(O,O) hydrogen bonds result in the formation of planar six- and five-membered rings. In the intermolecular O—H⋯O and C—H⋯O hydrogen bonds link the molecules into chains. π–π contacts between benzene rings [centroid–centroid distance = 3.5065 (9) Å] may further stabilize the structure. There also exists a weak C—H⋯π interaction.
Related literature
For general background, see: Büyükgüngör et al. (2007); Hökelek et al. (2004); Odabaşoğlu et al. (2004). For related structures, see: Özek et al. (2007, 2008); Ersanlı et al. (2003).
Experimental
Crystal data
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Refinement
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Data collection: X-AREA (Stoe & Cie, 2002); cell X-RED32 (Stoe & Cie, 2002); data reduction: X-RED32; 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).
Supporting information
10.1107/S160053680901410X/hk2658sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S160053680901410X/hk2658Isup2.hkl
For the preparation of the title compound, the mixture of 5-methoxysalicyl- aldehyde (0.5 g, 3.3 mmol) in ethanol (20 ml) and 2-hydroxy-5-chloroaniline (0.47 g, 3.3 mmol) in ethanol (20 ml) was stirred for 1 h under reflux. Crystals suitable for X-ray analysis were obtained from methanol by slow evaporation (yield; % 84, m.p. 415–416 K).
H atoms of water molecule and hydroxy group were located in difference Fourier maps and refined isotropically, with restrains of O3—H3A = 0.852 (17) and O4—H4A = 0.831 (19) Å. The remaining H atoms were positioned geometrically with N—H = 0.86 Å (for NH) and C—H = 0.93 and 0.96 Å, for aromatic and methyl H atoms,respectively, and constrained to ride on their parent atoms, with Uiso(H) = xUeq(C,N), where x = 1.5 for methyl H and x = 1.2 for all other H atoms.
Data collection: X-AREA (Stoe & Cie, 2002); cell
X-RED32 (Stoe & Cie, 2002); data reduction: X-RED32 (Stoe & Cie, 2002); 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).Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Hydrogen bonds are shown as dashed lines. | |
Fig. 2. A partial packing diagram of the title compound. Hydrogen bonds are shown as dashed lines. |
C14H12ClNO3·0.25H2O | F(000) = 1162 |
Mr = 279.95 | Dx = 1.495 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 6976 reflections |
a = 21.3670 (11) Å | θ = 2.0–28.0° |
b = 6.7600 (3) Å | µ = 0.31 mm−1 |
c = 17.7404 (9) Å | T = 100 K |
β = 103.841 (4)° | Prism, red |
V = 2488.0 (2) Å3 | 0.68 × 0.54 × 0.41 mm |
Z = 8 |
Stoe IPDS-II diffractometer | 2588 independent reflections |
Radiation source: fine-focus sealed tube | 2352 reflections with I > 2σ(I) |
Plane graphite monochromator | Rint = 0.022 |
Detector resolution: 6.67 pixels mm-1 | θmax = 26.5°, θmin = 2.0° |
ω scans | h = −25→26 |
Absorption correction: integration (X-RED32; Stoe & Cie, 2002) | k = −8→7 |
Tmin = 0.970, Tmax = 0.970 | l = −22→22 |
6976 measured reflections |
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)] = 0.031 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.086 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.09 | w = 1/[σ2(Fo2) + (0.0376P)2 + 3.3917P] where P = (Fo2 + 2Fc2)/3 |
2588 reflections | (Δ/σ)max = 0.001 |
186 parameters | Δρmax = 0.28 e Å−3 |
2 restraints | Δρmin = −0.31 e Å−3 |
C14H12ClNO3·0.25H2O | V = 2488.0 (2) Å3 |
Mr = 279.95 | Z = 8 |
Monoclinic, C2/c | Mo Kα radiation |
a = 21.3670 (11) Å | µ = 0.31 mm−1 |
b = 6.7600 (3) Å | T = 100 K |
c = 17.7404 (9) Å | 0.68 × 0.54 × 0.41 mm |
β = 103.841 (4)° |
Stoe IPDS-II diffractometer | 2588 independent reflections |
Absorption correction: integration (X-RED32; Stoe & Cie, 2002) | 2352 reflections with I > 2σ(I) |
Tmin = 0.970, Tmax = 0.970 | Rint = 0.022 |
6976 measured reflections |
R[F2 > 2σ(F2)] = 0.031 | 2 restraints |
wR(F2) = 0.086 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.09 | Δρmax = 0.28 e Å−3 |
2588 reflections | Δρmin = −0.31 e Å−3 |
186 parameters |
Experimental. 141 frames, detector distance = 100 mm |
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. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
C1 | 0.64391 (7) | 0.8209 (2) | 0.49336 (8) | 0.0163 (3) | |
C2 | 0.63352 (7) | 0.6614 (2) | 0.43854 (8) | 0.0171 (3) | |
C3 | 0.58193 (7) | 0.6836 (2) | 0.37118 (9) | 0.0191 (3) | |
H3 | 0.5736 | 0.5834 | 0.3342 | 0.023* | |
C4 | 0.54480 (7) | 0.8493 (2) | 0.36036 (8) | 0.0189 (3) | |
H4 | 0.5112 | 0.8593 | 0.3162 | 0.023* | |
C5 | 0.55578 (7) | 1.0069 (2) | 0.41439 (8) | 0.0175 (3) | |
C6 | 0.60491 (7) | 0.9945 (2) | 0.47962 (8) | 0.0170 (3) | |
H6 | 0.6129 | 1.0986 | 0.5149 | 0.020* | |
C7 | 0.51514 (8) | 1.3060 (2) | 0.45380 (9) | 0.0211 (3) | |
H7A | 0.5063 | 1.2434 | 0.4987 | 0.032* | |
H7B | 0.4832 | 1.4055 | 0.4349 | 0.032* | |
H7C | 0.5570 | 1.3663 | 0.4675 | 0.032* | |
C8 | 0.69160 (7) | 0.8057 (2) | 0.56359 (8) | 0.0164 (3) | |
H8 | 0.6987 | 0.9125 | 0.5976 | 0.020* | |
C9 | 0.77299 (7) | 0.6029 (2) | 0.65047 (8) | 0.0158 (3) | |
C10 | 0.79878 (7) | 0.4110 (2) | 0.65524 (9) | 0.0181 (3) | |
C11 | 0.84717 (7) | 0.3589 (2) | 0.71999 (9) | 0.0201 (3) | |
H11 | 0.8645 | 0.2321 | 0.7238 | 0.024* | |
C12 | 0.86950 (7) | 0.4950 (2) | 0.77875 (8) | 0.0190 (3) | |
H12 | 0.9020 | 0.4604 | 0.8218 | 0.023* | |
C13 | 0.84290 (7) | 0.6831 (2) | 0.77270 (8) | 0.0175 (3) | |
C14 | 0.79444 (7) | 0.7395 (2) | 0.70949 (8) | 0.0172 (3) | |
H14 | 0.7767 | 0.8657 | 0.7066 | 0.021* | |
Cl1 | 0.873014 (18) | 0.85790 (6) | 0.84450 (2) | 0.02270 (12) | |
N1 | 0.72613 (6) | 0.64456 (19) | 0.58204 (7) | 0.0165 (3) | |
H1 | 0.7192 | 0.5522 | 0.5477 | 0.020* | |
O1 | 0.66836 (5) | 0.50302 (16) | 0.45048 (6) | 0.0219 (3) | |
O2 | 0.51359 (5) | 1.16195 (17) | 0.39490 (6) | 0.0229 (3) | |
O3 | 0.77355 (5) | 0.28754 (18) | 0.59629 (7) | 0.0236 (3) | |
H3A | 0.7990 (11) | 0.196 (3) | 0.5898 (15) | 0.055 (8)* | |
O4 | 0.5000 | 0.3573 (10) | 0.2500 | 0.0253 (14) | 0.25 |
H4A | 0.500 (4) | 0.286 (5) | 0.2880 (13) | 0.03 (2)* | 0.25 |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0144 (7) | 0.0192 (7) | 0.0150 (6) | −0.0005 (6) | 0.0028 (5) | −0.0001 (6) |
C2 | 0.0154 (7) | 0.0190 (7) | 0.0166 (7) | 0.0000 (6) | 0.0033 (5) | −0.0010 (6) |
C3 | 0.0184 (7) | 0.0226 (8) | 0.0155 (7) | −0.0012 (6) | 0.0023 (6) | −0.0039 (6) |
C4 | 0.0166 (7) | 0.0262 (8) | 0.0127 (7) | −0.0004 (6) | 0.0012 (5) | 0.0000 (6) |
C5 | 0.0158 (7) | 0.0202 (7) | 0.0167 (7) | 0.0021 (6) | 0.0043 (5) | 0.0017 (6) |
C6 | 0.0173 (7) | 0.0187 (7) | 0.0147 (6) | 0.0001 (6) | 0.0037 (5) | −0.0016 (5) |
C7 | 0.0221 (8) | 0.0180 (7) | 0.0213 (7) | 0.0030 (6) | 0.0017 (6) | −0.0009 (6) |
C8 | 0.0142 (7) | 0.0192 (7) | 0.0161 (7) | −0.0004 (6) | 0.0045 (5) | −0.0018 (6) |
C9 | 0.0119 (6) | 0.0217 (7) | 0.0139 (6) | 0.0004 (6) | 0.0031 (5) | 0.0008 (6) |
C10 | 0.0165 (7) | 0.0194 (7) | 0.0180 (7) | 0.0003 (6) | 0.0031 (6) | −0.0021 (6) |
C11 | 0.0178 (7) | 0.0196 (7) | 0.0220 (7) | 0.0035 (6) | 0.0030 (6) | 0.0025 (6) |
C12 | 0.0153 (7) | 0.0245 (8) | 0.0158 (7) | 0.0016 (6) | 0.0011 (5) | 0.0043 (6) |
C13 | 0.0143 (7) | 0.0235 (8) | 0.0146 (7) | −0.0019 (6) | 0.0035 (5) | −0.0017 (6) |
C14 | 0.0158 (7) | 0.0183 (7) | 0.0166 (7) | 0.0018 (6) | 0.0021 (5) | 0.0009 (6) |
Cl1 | 0.0219 (2) | 0.0258 (2) | 0.01674 (19) | 0.00025 (14) | −0.00266 (14) | −0.00406 (14) |
N1 | 0.0151 (6) | 0.0184 (6) | 0.0142 (6) | 0.0007 (5) | 0.0001 (5) | −0.0018 (5) |
O1 | 0.0205 (5) | 0.0206 (6) | 0.0221 (5) | 0.0040 (4) | 0.0002 (4) | −0.0053 (4) |
O2 | 0.0226 (6) | 0.0233 (6) | 0.0189 (5) | 0.0078 (4) | −0.0030 (4) | −0.0015 (4) |
O3 | 0.0206 (6) | 0.0228 (6) | 0.0238 (6) | 0.0049 (5) | −0.0016 (4) | −0.0077 (5) |
O4 | 0.036 (4) | 0.021 (3) | 0.016 (3) | 0.000 | −0.001 (3) | 0.000 |
C1—C8 | 1.412 (2) | C8—H8 | 0.9300 |
C1—C6 | 1.426 (2) | C9—C14 | 1.389 (2) |
C1—C2 | 1.433 (2) | C9—C10 | 1.404 (2) |
C2—O1 | 1.2924 (18) | C9—N1 | 1.4050 (18) |
C2—C3 | 1.427 (2) | C10—O3 | 1.3459 (18) |
C3—C4 | 1.359 (2) | C10—C11 | 1.395 (2) |
C3—H3 | 0.9300 | C11—C12 | 1.387 (2) |
C4—C5 | 1.415 (2) | C11—H11 | 0.9300 |
C4—H4 | 0.9300 | C12—C13 | 1.386 (2) |
C5—C6 | 1.366 (2) | C12—H12 | 0.9300 |
C5—O2 | 1.3720 (18) | C13—C14 | 1.385 (2) |
C6—H6 | 0.9300 | C13—Cl1 | 1.7438 (15) |
C7—O2 | 1.4229 (19) | C14—H14 | 0.9300 |
C7—H7A | 0.9600 | N1—H1 | 0.8600 |
C7—H7B | 0.9600 | O3—H3A | 0.852 (17) |
C7—H7C | 0.9600 | O4—H4A | 0.831 (19) |
C8—N1 | 1.3122 (19) | ||
C8—C1—C6 | 118.69 (13) | N1—C8—H8 | 119.2 |
C8—C1—C2 | 120.36 (14) | C1—C8—H8 | 119.2 |
C6—C1—C2 | 120.91 (13) | C14—C9—C10 | 120.98 (13) |
O1—C2—C3 | 121.57 (14) | C14—C9—N1 | 123.82 (13) |
O1—C2—C1 | 121.51 (13) | C10—C9—N1 | 115.19 (13) |
C3—C2—C1 | 116.90 (14) | O3—C10—C11 | 124.28 (14) |
C4—C3—C2 | 120.85 (14) | O3—C10—C9 | 116.60 (13) |
C4—C3—H3 | 119.6 | C11—C10—C9 | 119.10 (14) |
C2—C3—H3 | 119.6 | C12—C11—C10 | 120.35 (14) |
C3—C4—C5 | 121.89 (13) | C12—C11—H11 | 119.8 |
C3—C4—H4 | 119.1 | C10—C11—H11 | 119.8 |
C5—C4—H4 | 119.1 | C13—C12—C11 | 119.30 (13) |
C6—C5—O2 | 125.86 (14) | C13—C12—H12 | 120.3 |
C6—C5—C4 | 119.79 (14) | C11—C12—H12 | 120.3 |
O2—C5—C4 | 114.34 (12) | C14—C13—C12 | 121.88 (14) |
C5—C6—C1 | 119.64 (14) | C14—C13—Cl1 | 118.58 (12) |
C5—C6—H6 | 120.2 | C12—C13—Cl1 | 119.49 (11) |
C1—C6—H6 | 120.2 | C13—C14—C9 | 118.37 (14) |
O2—C7—H7A | 109.5 | C13—C14—H14 | 120.8 |
O2—C7—H7B | 109.5 | C9—C14—H14 | 120.8 |
H7A—C7—H7B | 109.5 | C8—N1—C9 | 128.60 (13) |
O2—C7—H7C | 109.5 | C8—N1—H1 | 115.7 |
H7A—C7—H7C | 109.5 | C9—N1—H1 | 115.7 |
H7B—C7—H7C | 109.5 | C5—O2—C7 | 116.07 (11) |
N1—C8—C1 | 121.66 (14) | C10—O3—H3A | 114.0 (18) |
C8—C1—C2—O1 | −2.1 (2) | C14—C9—C10—C11 | −0.7 (2) |
C6—C1—C2—O1 | −179.69 (14) | N1—C9—C10—C11 | 177.86 (14) |
C8—C1—C2—C3 | 176.39 (14) | O3—C10—C11—C12 | −178.82 (15) |
C6—C1—C2—C3 | −1.2 (2) | C9—C10—C11—C12 | −0.1 (2) |
O1—C2—C3—C4 | 178.48 (14) | C10—C11—C12—C13 | 0.5 (2) |
C1—C2—C3—C4 | 0.0 (2) | C11—C12—C13—C14 | 0.0 (2) |
C2—C3—C4—C5 | 0.6 (2) | C11—C12—C13—Cl1 | −177.44 (12) |
C3—C4—C5—C6 | 0.0 (2) | C12—C13—C14—C9 | −0.9 (2) |
C3—C4—C5—O2 | −179.47 (14) | Cl1—C13—C14—C9 | 176.63 (11) |
O2—C5—C6—C1 | 178.19 (14) | C10—C9—C14—C13 | 1.2 (2) |
C4—C5—C6—C1 | −1.2 (2) | N1—C9—C14—C13 | −177.27 (14) |
C8—C1—C6—C5 | −175.82 (14) | C1—C8—N1—C9 | −176.94 (14) |
C2—C1—C6—C5 | 1.8 (2) | C14—C9—N1—C8 | −5.5 (2) |
C6—C1—C8—N1 | 175.38 (14) | C10—C9—N1—C8 | 175.95 (14) |
C2—C1—C8—N1 | −2.3 (2) | C6—C5—O2—C7 | −10.6 (2) |
C14—C9—C10—O3 | 178.07 (14) | C4—C5—O2—C7 | 168.79 (13) |
N1—C9—C10—O3 | −3.3 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O1 | 0.86 | 1.84 | 2.5511 (16) | 140 |
N1—H1···O3 | 0.86 | 2.19 | 2.6063 (17) | 109 |
C3—H3···O4 | 0.93 | 2.43 | 3.279 (5) | 151 |
O4—H4A···O2i | 0.83 (2) | 2.03 (2) | 2.842 (3) | 166 (6) |
O3—H3A···O1ii | 0.85 (2) | 1.74 (2) | 2.5652 (16) | 162 (3) |
C12—H12···O2iii | 0.93 | 2.56 | 3.4372 (18) | 157 |
C7—H7A···Cg1iv | 0.96 | 2.83 | 3.644 (2) | 143 |
Symmetry codes: (i) x, y−1, z; (ii) −x+3/2, −y+1/2, −z+1; (iii) x+1/2, −y+3/2, z+1/2; (iv) x+1/2, y+3/2, z. |
Experimental details
Crystal data | |
Chemical formula | C14H12ClNO3·0.25H2O |
Mr | 279.95 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 100 |
a, b, c (Å) | 21.3670 (11), 6.7600 (3), 17.7404 (9) |
β (°) | 103.841 (4) |
V (Å3) | 2488.0 (2) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.31 |
Crystal size (mm) | 0.68 × 0.54 × 0.41 |
Data collection | |
Diffractometer | Stoe IPDS-II diffractometer |
Absorption correction | Integration (X-RED32; Stoe & Cie, 2002) |
Tmin, Tmax | 0.970, 0.970 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6976, 2588, 2352 |
Rint | 0.022 |
(sin θ/λ)max (Å−1) | 0.628 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.031, 0.086, 1.09 |
No. of reflections | 2588 |
No. of parameters | 186 |
No. of restraints | 2 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.28, −0.31 |
Computer programs: X-AREA (Stoe & Cie, 2002), X-RED32 (Stoe & Cie, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O1 | 0.86 | 1.84 | 2.5511 (16) | 139.5 |
N1—H1···O3 | 0.86 | 2.19 | 2.6063 (17) | 109.1 |
C3—H3···O4 | 0.93 | 2.43 | 3.279 (5) | 151.3 |
O4—H4A···O2i | 0.831 (19) | 2.029 (19) | 2.842 (3) | 166 (6) |
O3—H3A···O1ii | 0.852 (17) | 1.743 (18) | 2.5652 (16) | 162 (3) |
C12—H12···O2iii | 0.93 | 2.56 | 3.4372 (18) | 156.5 |
C7—H7A···Cg1iv | 0.96 | 2.834 | 3.644 (2) | 142.64 |
Symmetry codes: (i) x, y−1, z; (ii) −x+3/2, −y+1/2, −z+1; (iii) x+1/2, −y+3/2, z+1/2; (iv) x+1/2, y+3/2, z. |
Acknowledgements
The authors acknowledge the Faculty of Arts and Sciences, Ondokuz Mayıs University, Turkey, for the use of the diffractometer (purchased under grant No. F.279 of the University Research Fund).
References
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As part of our ongoing studies on the syntheses and structural characterizations of Schiff-base compounds (Özek et al., 2008; Özek et al., 2007), we report herein the crystal structure of the title compound.
In general, o-hydroxy Schiff bases exhibit two possible tautomeric forms, namely, phenol-imine and keto-amine. In the solid state, the keto-amine form is observed in naphthaldimine (Odabaşoǧlu et al., 2004), while the phenol-imine form is observed in salicylaldimine (Büyükgüngör et al., 2007) Schiff bases. However, naphthaldimine and salicylaldimine can also exist in the phenol-imine and keto-amine forms, respectively depending on the stereochemistry of the molecule and the type of nitrogen substituents in naphthaldimine and salicylaldimine Schiff bases (Hökelek et al., 2004).
In the title compound (Fig. 1), the keto-amine form is favored over the phenol-imine form, as indicated by C2—O1 [1.2924 (18) Å], C8—N1 [1.3122 (19) Å], C1—C8 [1.412 (2) Å] and C1—C2 [1.433 (2) Å] bonds. The C2—O1 and C8—N1 bonds indicate double-bond and a high degree of single-bond characters, respectively. Similar results were observed for 2-[(2-hydroxy-4-nitrophenyl) -aminomethylene]cyclohexa-3,5-dien-1(2H)-οne [C—O = 1.298 (2) and C—N = 1.308 (2) Å; Ersanlı et al., 2003].
It is known that Schiff bases may exhibit thermochromism or photochromism, depending on the planarity or non-planarity of the molecule, respectively. Therefore, one can expect thermochromic properties in the title compound caused by planarity of the molecule; the dihedral angle between rings A (C1—C6) and B (C9—C14) is 7.24 (7)°. Intramolecular N—H···O hydrogen bonds (Table 1) result in the formations of planar six- and five-membered rings C (O1/N1/C1/C2/C8/H1) and D (O3/N1/C9/C10/H1). They are oriented with respect to the adjacent rings at dihedral angles of A/C = 4.44 (9), A/D = 9.6 (9), B/C = 5.42 (9), B/D = 2.96 (9) and C/D = 6.55 (9)°. So, they are nearly coplanar.
In the crystal structure, intermolecular O—H···O and C—H···O hydrogen bonds (Table 1) link the molecules into chains (Fig. 2), in which they may be effective in the stabilization of the structure. The π–π contact between the phenyl rings, Cg1—Cg2i [symmetry code: (i) 1/2 - x, 3/2 - y, -z, where Cg1 and Cg2 are centroids of the rings A (C1—C6) and B (C9—C14), respectively] may further stabilize the structure, with centroid-centroid distance of 3.5065 (9) Å. There also exists a weak C—H···π interaction (Table 1).