(E)-4-Chloro-2-[(4-hy­droxy-3-meth­oxy­benzyl­idene)amino]­phenol

Marir, A.; Boudinar, Y.; Boukhemis, O.; Djedouani, A.; Jeanneau, E.; Stoeckli-Evans, H.

doi:10.1107/S2414314626005523

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 11| Part 5| May 2026| x260552

https://doi.org/10.1107/S2414314626005523

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(E)-4-Chloro-2-[(4-hydroxy-3-methoxybenzylidene)amino]phenol

Amel Marir,^a Yamina Boudinar,^b,^c Ouafa Boukhemis,^d,^e Amel Djedouani,^f,^g ^* Erwann Jeanneau ^h and Helen Stoeckli-Evans ⁱ ^*‡

^aFaculté des Sciences Exacte, Université des Fréres Mentouri-Constantine 1, Algeria, ^bDepartment of Chemistry, Faculty of Sciences, University of 20 August 1955, Skikda 21000, Algeria, ^cLaboratory of Physico-Chemistry Research on Surfaces and Interfaces, University of Skikda, 21000, Algeria, ^dNational Biotechnology Research Center (CRBT), Industrial Biotechnology Division, Ali Mendjli New City, UV03 BP E73, Constantine 25000, Algeria, ^eUnité de Recherche de Chimie de l'Environnement et Moléculaire Structurale, Université de Constantine-1, 25000, Constantine, Algeria, ^fEcole Normale Supérieure de Constantine-Assia Djebar, Université Constantine 3, 25000, Ali Mendjli, Algeria, ^gLaboratoire des Produits Naturels D'Origine Végétale et de Synthése Organique, Faculté des Sciences Exactes, Université des Fréres Mentouri-Constantine 1, Algeria, ^hCentre de Diffractométrie Henri Longchambon, Université Claude Bernard Lyon1, 5 rue de la Doua, 69100 Villeurbanne, France, and ⁱInstitute of Physics, University of Neuchâtel, Rue Emile-Argand 11, CH-2000 Neuchâtel, Switzerland
^*Correspondence e-mail: [email protected], [email protected]

Edited by W. T. A. Harrison, University of Aberdeen, United Kingdom (Received 22 May 2026; accepted 25 May 2026; online 29 May 2026)

The title compound, C₁₄H₁₂ClNO₃ (I), was obtained from the reaction of 2-amino-4-chloro phenol with vanillin (4-hydroxy-3-methoxybenzaldehyde). It crystallizes with two conformationally different molecules in the asymmetric unit. In one of the molecules, the 4-chloro-2(methyleneamino)phenol moiety is partially positionally disordered with the refined occupancies being 0.850 (2):0.150 (2). In both molecules there are intramolecular O—H⋯O and O—H⋯N hydrogen bonds, all enclosing S(5) ring motifs. The configuration about the azomethine bond is E in both molecules. The extended structure features O—H⋯O, C—H⋯Cl, C—H⋯O hydrogen bonds, as well as C—H⋯π and parallel displaced π–π interactions, which lead to the formation of a three-dimensional network.

Keywords: crystal structure; vanillin; Schiff base; hydrogen bonding.

CCDC reference: 2448683

Structure description

Vanillins have biological importance, for example as a bacterial cofactor involved in the synthesis of folic acid (Robinson, 1966 ). Hydroxy Schiff bases have been widely investigated for their biological, photochromic, and thermochromic properties (Garnovskii et al., 1993 ; Hadjoudis et al., 2004 ). They therefore represent promising candidates for optical memory and switching devices (Zhao et al., 2007 ). The title Schiff base vanillin derivative, C₁₄H₁₂ClNO₃ (I), was synthesized as part of a broader search for multifunctional imine-bases.

Compound (I) crystallizes with two independent molecules (1 and 2) in the asymmetric unit of the monoclinic space group P2₁ with a well defined absolute structure [refined Flack parameter = −0.004 (5)]. The molecular structures of the two molecules are illustrated in Fig. 1. In both molecules there are intramolecular O—H⋯O and O—H⋯N hydrogen bonds, all enclosing S(5) ring motifs (Fig. 1 and Table 1). The configuration about the azomethine bond is E in both molecules.

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 is the centroid of the C22–C27 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1	0.84	2.21	2.695 (3)	116
O3—H3⋯O2	0.84	2.25	2.690 (3)	113
O4A—H4A⋯N2A	0.84	2.20	2.675 (4)	116
O6—H6⋯O5	0.84	2.18	2.645 (3)	115
O1—H1⋯O3ⁱ	0.84	2.26	2.854 (3)	128
O3—H3⋯O6ⁱⁱ	0.84	2.02	2.714 (3)	140
O6—H6⋯O1ⁱⁱⁱ	0.84	2.05	2.716 (3)	136
C2—H2⋯Cl2B^iv	0.95	2.71	3.449 (8)	135
C14—H14B⋯O4B^v	0.98	2.31	2.928 (16)	120
C28—H28C⋯O4A^vi	0.98	2.57	3.142 (4)	117
C7—H7⋯Cg2ⁱ	0.95	2.90	3.394 (3)	113
Symmetry codes: (i) $[-x, y-{\script{1\over 2}}, -z+1]$ ; (ii) ; (iii) $[-x-1, y+{\script{1\over 2}}, -z+1]$ ; (iv) ; (v) $[-x+1, y+{\script{1\over 2}}, -z+1]$ ; (vi) $[-x, y+{\script{1\over 2}}, -z+2]$ .

Figure 1
The molecular structure of (I) with displacement ellipsoids drawn at the 50% probability level. In this and subsequent figures the various hydrogen bonds (Table 1

) are shown as cyan dashed lines. Only the major disorder component of molecule 2 containing N2A is shown.

In molecule 2, the 4-chloro-2(methyleneamino)phenol moiety is positionally disordered over two sets of sites with refined occupancies (A:B) of 0.850 (2):0.150 (2). The disorder components are related by a pseudo twofold rotation axis on which lies the benzene ring atom C22. In molecule 1 the 2-methoxyphenol ring is inclined to the 4-chloro-2(methyleneamino)phenol ring by 36.1 (1)°, compared to 5.7 (2)° in molecule 2 for the major component and 7.6 (8)° for the minor component. The disordered 4-chloro-2(methyleneamino)phenol rings are inclined to each other by 2.7 (8)°. The azomethine bond lengths are normal and of almost the same value: C7=N1, C21A=N2A and C21B=N2B are 1.277 (4), 1.279 (4) and 1.269 (12) Å, respectively.

These geometrical parameters are similar to those observed in three similar compounds located in the Cambridge Structural Database (V6.01, last update February 2026; Groom et al., 2016 ), namely (E)-4-[(4-bromophenyl)iminomethyl]-2-methoxyphenol (II) (CSD refcode: LEFVID; Fejfarová et al., 2012 ), 4-[(4-chlorophenyl)iminomethyl]-2-methoxyphenol (III) (YIFYAO; Shang & Tan, 2007 ) and 4-{[(3-chloro-4-fluorophenyl)imino]methyl}-2-methoxyphenol (IV) (IREQEF; Suresh Babu et al., 2026 ). The dihedral angle between the aromatic rings are 37.9 (1)° for II, 44.4 (1)° for III and 43.4 (2)° for IV, compared to 36.1 (1)° for molecule 1 of the title compound (I). The azomethine bond lengths are 1.283 (3) Å for I, 1.272 (3) Å for II and 1.269 (4) Å for IV; close to the values observed in molecules 1 and 2 of compound (I).

In the extended structure of (I), the 1 molecules are linked by an O1—H1⋯O3ⁱ hydrogen bond (Table 1) forming a helical chain propagating along the b-axis direction (Fig. 2, Table 1). An interesting triangular arrangement with an R₃³(6) ring motif is formed by O—H⋯O hydrogen bonds involving two 1 molecules and one 2 molecule (Fig. 3, Table 1). There are also C—H⋯Cl and C—H⋯O hydrogen bonds present (Table 1). The combination of all these hydrogen bonds together with C—H⋯π and parallel displaced π–π interactions [Cg1⋯Cg4ⁱ = 3.701 (2) Å, where Cg1 and Cg4 are the centroids of rings C15A–C20A and C1–C6, respectively] leads to the formation of a three-dimensional network (Fig. 4).

Figure 2
A view along the a axis of the helical chain formed by O1—H1⋯O3ⁱ hydrogen bonds involving molecules 1 of compound (I). Symmetry code: (i) −x, y − $[{1\over 2}]$ , −z + 1.

Figure 3
A view along the b axis of the hydrogen-bonded R₃³(6) ring motif involving two molecule 1 (blue) and one molecule 2 (red) of compound (I). Only the major disorder component of molecule 2 is shown. Symmetry codes: (i) −x, y − $[{1\over 2}]$ , −z + 1; (iii) −x − 1, y + $[{1\over 2}]$ , −z + 1.

Figure 4
A view along the a axis of the packing of compound (I). The minor disordered fragment of molecule 2 is shown in pale green.

Synthesis and crystallization

To a solution of vanillin (0.01 mmol) in ethanol (20 ml) was added a solution of 2-amino-4-chloro phenol (0.01 mmol) also dissolved in ethanol (20 ml). The reaction mixture was stirred for 2.5 h under reflux. The product obtained was filtered off, recrystallized from ethanol solution and then dried in vacuo to give compound (I) [yield 59%; m.p. 525 K]. Yellow crystals of (I), suitable for X-ray analysis, were obtained by slow evaporation of an ethanol solution.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. The hydrogen atoms were fixed geometrically (O—H = 0.84 Å, C—H = 0.95–0.98 Å) and allowed to ride on their parent atoms with U_iso(H) = 1.5U_eq(OH and C-methyl) and 1.2U_eq(C) for other H atoms. The bond lengths and the U_iso/U_aniso values of the atoms of minor component (B) of the disordered moiety of molecule 2 were restrained to be equal to those of the major component (A).

Table 2
Experimental details

Crystal data
Chemical formula	C₁₄H₁₂ClNO₃
M_r	277.70
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	100
a, b, c (Å)	9.5413 (1), 7.0494 (1), 18.9614 (2)
β (°)	97.187 (1)
V (Å³)	1265.33 (3)
Z	4
Radiation type	Cu Kα
μ (mm⁻¹)	2.72
Crystal size (mm)	0.21 × 0.19 × 0.03

Data collection
Diffractometer	XtaLAB Synergy, Dualflex, HyPix-Arc 100
Absorption correction	Gaussian (CrysAlis PRO; Rigaku OD, 2025 )
T_min, T_max	0.583, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	45219, 5122, 4984
R_int	0.032
(sin θ/λ)_max (Å⁻¹)	0.638

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.082, 1.07
No. of reflections	5122
No. of parameters	442
No. of restraints	395
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.30
Absolute structure	Flack x determined using 2147 quotients [(I⁺)−(I⁻)]/[(I⁺)+(I⁻)] (Parsons et al., 2013 ).
Absolute structure parameter	−0.004 (5)
Computer programs: CrysAlis PRO (Rigaku OD, 2025), SHELXT2018/2 (Sheldrick, 2015a ), OLEX2 (Dolomanov et al., 2009 ), SHELXL 2018/3 (Sheldrick, 2015b ), Mercury (Macrae et al., 2020 ), PLATON (Spek, 2020 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 2448683

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S2414314626005523/hb4564sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314626005523/hb4564Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314626005523/hb4564Isup3.cml

checkCIF report

Computing details top

(E)-4-Chloro-2-[(4-hydroxy-3-methoxybenzylidene)amino]phenol top

Crystal data top

C₁₄H₁₂ClNO₃	F(000) = 576
M_r = 277.70	D_x = 1.458 Mg m⁻³
Monoclinic, P2₁	Cu Kα radiation, λ = 1.54184 Å
a = 9.5413 (1) Å	Cell parameters from 33083 reflections
b = 7.0494 (1) Å	θ = 4.6–77.6°
c = 18.9614 (2) Å	µ = 2.72 mm⁻¹
β = 97.187 (1)°	T = 100 K
V = 1265.33 (3) Å³	Plate, black
Z = 4	0.21 × 0.19 × 0.03 mm

Data collection top

XtaLAB Synergy, Dualflex, HyPix-Arc 100 diffractometer	5122 independent reflections
Radiation source: micro-focus sealed X-ray tube, PhotonJet (Cu) X-ray Source	4984 reflections with I > 2σ(I)
Mirror monochromator	R_int = 0.032
Detector resolution: 10.0000 pixels mm^-1	θ_max = 79.5°, θ_min = 4.7°
ω scans	h = −11→11
Absorption correction: gaussian (CrysAlisPro; Rigaku OD, 2025)	k = −8→8
T_min = 0.583, T_max = 1.000	l = −24→23
45219 measured reflections

Refinement top

Refinement on F²	H-atom parameters constrained
Least-squares matrix: full	w = 1/[σ²(F_o²) + (0.0367P)² + 0.6939P] where P = (F_o² + 2F_c²)/3
R[F² > 2σ(F²)] = 0.033	(Δ/σ)_max = 0.001
wR(F²) = 0.082	Δρ_max = 0.22 e Å⁻³
S = 1.07	Δρ_min = −0.30 e Å⁻³
5122 reflections	Extinction correction: (SHELXL2018/3; Sheldrick, 2015b), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
442 parameters	Extinction coefficient: 0.0011 (3)
395 restraints	Absolute structure: Flack x determined using 2147 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons et al., 2013).
Primary atom site location: dual	Absolute structure parameter: −0.004 (5)
Hydrogen site location: inferred from neighbouring sites

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq	Occ. (<1)
Cl1	0.01708 (7)	0.48290 (11)	0.03832 (3)	0.03065 (17)
O1	−0.3043 (2)	0.1573 (3)	0.25322 (10)	0.0280 (4)
H1	−0.259951	0.174431	0.293848	0.042*
O2	0.4630 (2)	0.4355 (3)	0.51340 (10)	0.0325 (5)
O3	0.2779 (2)	0.5063 (4)	0.60610 (10)	0.0355 (5)
H3	0.364488	0.480950	0.613973	0.053*
N1	−0.0586 (2)	0.3329 (3)	0.29857 (12)	0.0241 (5)
C1	−0.0740 (3)	0.3750 (4)	0.10189 (14)	0.0242 (6)
C2	−0.2020 (3)	0.2866 (4)	0.08055 (15)	0.0259 (6)
H2	−0.236672	0.276652	0.031502	0.031*
C3	−0.2792 (3)	0.2123 (4)	0.13181 (16)	0.0262 (6)
H3A	−0.366968	0.150878	0.117979	0.031*
C4	−0.2273 (3)	0.2287 (4)	0.20289 (15)	0.0235 (5)
C5	−0.0967 (3)	0.3146 (4)	0.22449 (14)	0.0218 (5)
C6	−0.0200 (3)	0.3885 (4)	0.17267 (14)	0.0225 (5)
H6A	0.068753	0.447708	0.186105	0.027*
C7	0.0722 (3)	0.3355 (4)	0.32331 (15)	0.0238 (5)
H7	0.139799	0.311035	0.291697	0.029*
C8	0.1228 (3)	0.3742 (4)	0.39765 (14)	0.0241 (6)
C9	0.2686 (3)	0.3771 (4)	0.41894 (14)	0.0243 (6)
H9	0.331511	0.346927	0.385497	0.029*
C10	0.3224 (3)	0.4231 (4)	0.48776 (15)	0.0257 (6)
C11	0.2293 (3)	0.4636 (4)	0.53746 (14)	0.0269 (6)
C12	0.0850 (3)	0.4613 (4)	0.51677 (14)	0.0266 (6)
H12	0.022182	0.489326	0.550477	0.032*
C13	0.0312 (3)	0.4184 (4)	0.44712 (14)	0.0260 (6)
H13	−0.067986	0.419123	0.433177	0.031*
C14	0.5597 (3)	0.4389 (5)	0.46143 (16)	0.0362 (7)
H14A	0.655236	0.464287	0.484917	0.054*
H14B	0.531856	0.538831	0.426542	0.054*
H14C	0.558057	0.315888	0.437259	0.054*
Cl2A	0.61960 (8)	−0.00605 (13)	0.75094 (4)	0.0330 (2)	0.850 (2)
Cl2B	0.5418 (7)	0.0967 (13)	0.9561 (4)	0.0549 (19)	0.150 (2)
O4A	0.2755 (3)	0.3018 (4)	0.95883 (13)	0.0324 (6)	0.850 (2)
H4A	0.192939	0.322718	0.939384	0.049*	0.850 (2)
O4B	0.3188 (16)	0.125 (3)	0.6549 (7)	0.043 (4)	0.150 (2)
H4B	0.268030	0.221346	0.645512	0.065*	0.150 (2)
O5	−0.3574 (2)	0.5535 (3)	0.82344 (10)	0.0322 (5)
O6	−0.4691 (2)	0.5218 (3)	0.68912 (10)	0.0336 (5)
H6	−0.503586	0.557855	0.725492	0.050*
N2A	0.1597 (3)	0.2935 (4)	0.82290 (15)	0.0220 (6)	0.850 (2)
N2B	0.1569 (16)	0.257 (3)	0.7449 (9)	0.029 (3)	0.150 (2)
C15A	0.5165 (4)	0.0862 (6)	0.8128 (2)	0.0263 (8)	0.850 (2)
C15B	0.4796 (17)	0.115 (3)	0.8662 (6)	0.033 (3)	0.150 (2)
C16A	0.5714 (4)	0.0890 (5)	0.88371 (18)	0.0293 (7)	0.850 (2)
H16A	0.663202	0.040906	0.898876	0.035*	0.850 (2)
C16B	0.562 (2)	0.055 (4)	0.8152 (8)	0.031 (3)	0.150 (2)
H16B	0.655735	0.013414	0.829141	0.037*	0.150 (2)
C17A	0.4890 (4)	0.1638 (6)	0.9323 (2)	0.0315 (8)	0.850 (2)
H17A	0.525101	0.168726	0.981242	0.038*	0.850 (2)
C17B	0.5071 (15)	0.056 (3)	0.7440 (8)	0.029 (3)	0.150 (2)
H17B	0.561093	0.008931	0.709024	0.035*	0.150 (2)
C18A	0.3545 (3)	0.2314 (5)	0.90979 (17)	0.0251 (7)	0.850 (2)
C18B	0.3722 (15)	0.127 (3)	0.7246 (7)	0.031 (3)	0.150 (2)
C19A	0.3001 (4)	0.2271 (5)	0.83757 (19)	0.0229 (7)	0.850 (2)
C19B	0.2913 (16)	0.196 (3)	0.7753 (7)	0.029 (3)	0.150 (2)
C20A	0.3837 (3)	0.1539 (5)	0.78864 (18)	0.0243 (6)	0.850 (2)
H20A	0.349394	0.150685	0.739408	0.029*	0.850 (2)
C20B	0.3450 (19)	0.188 (4)	0.8467 (9)	0.029 (3)	0.150 (2)
H20B	0.290374	0.232779	0.881952	0.035*	0.150 (2)
C21A	0.0944 (4)	0.2930 (5)	0.7597 (2)	0.0232 (8)	0.850 (2)
H21A	0.142836	0.251979	0.721620	0.028*	0.850 (2)
C21B	0.0758 (16)	0.308 (4)	0.7896 (9)	0.033 (4)	0.150 (2)
H21B	0.095063	0.314990	0.839954	0.039*	0.150 (2)
C22	−0.0536 (3)	0.3541 (4)	0.74452 (16)	0.0279 (6)
C23	−0.1313 (3)	0.4268 (4)	0.79672 (15)	0.0290 (6)
H23	−0.088500	0.437681	0.844539	0.035*
C24	−0.2693 (3)	0.4822 (4)	0.77865 (14)	0.0256 (5)
C25	−0.3328 (3)	0.4665 (4)	0.70778 (14)	0.0264 (6)
C26	−0.2570 (3)	0.3920 (4)	0.65653 (15)	0.0269 (6)
H26	−0.300329	0.378857	0.608869	0.032*
C27	−0.1180 (3)	0.3367 (4)	0.67500 (16)	0.0290 (6)
H27	−0.066043	0.286383	0.639691	0.035*
C28	−0.2971 (4)	0.5866 (5)	0.89510 (16)	0.0376 (7)
H28A	−0.214351	0.669073	0.895543	0.056*
H28B	−0.268475	0.465409	0.917827	0.056*
H28C	−0.367156	0.647938	0.921164	0.056*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0304 (3)	0.0323 (3)	0.0295 (3)	−0.0008 (3)	0.0046 (2)	0.0043 (3)
O1	0.0267 (10)	0.0309 (11)	0.0258 (10)	−0.0040 (8)	0.0005 (8)	0.0024 (8)
O2	0.0218 (10)	0.0450 (13)	0.0295 (10)	0.0000 (9)	−0.0017 (7)	−0.0051 (9)
O3	0.0277 (10)	0.0526 (14)	0.0253 (9)	0.0005 (11)	−0.0008 (7)	−0.0089 (10)
N1	0.0256 (12)	0.0198 (11)	0.0262 (11)	0.0001 (9)	0.0008 (9)	−0.0008 (9)
C1	0.0247 (14)	0.0195 (13)	0.0285 (13)	0.0030 (11)	0.0037 (10)	0.0012 (10)
C2	0.0286 (15)	0.0231 (14)	0.0249 (13)	0.0016 (11)	−0.0015 (11)	0.0002 (11)
C3	0.0230 (14)	0.0239 (14)	0.0303 (14)	−0.0021 (11)	−0.0028 (11)	0.0008 (11)
C4	0.0229 (13)	0.0186 (12)	0.0288 (14)	0.0026 (10)	0.0029 (11)	0.0030 (10)
C5	0.0221 (13)	0.0187 (13)	0.0236 (13)	0.0030 (10)	−0.0005 (10)	−0.0014 (10)
C6	0.0199 (12)	0.0171 (13)	0.0300 (13)	0.0029 (10)	0.0015 (10)	−0.0014 (10)
C7	0.0240 (14)	0.0211 (13)	0.0262 (13)	0.0013 (11)	0.0025 (10)	−0.0002 (10)
C8	0.0276 (14)	0.0190 (13)	0.0252 (13)	−0.0001 (11)	0.0009 (10)	0.0007 (10)
C9	0.0229 (13)	0.0246 (14)	0.0251 (13)	0.0012 (10)	0.0023 (10)	−0.0005 (10)
C10	0.0235 (13)	0.0231 (13)	0.0295 (13)	−0.0004 (11)	0.0001 (10)	0.0008 (11)
C11	0.0281 (13)	0.0289 (16)	0.0231 (12)	−0.0007 (12)	0.0008 (10)	−0.0020 (11)
C12	0.0266 (13)	0.0271 (15)	0.0266 (13)	−0.0014 (12)	0.0055 (10)	−0.0011 (11)
C13	0.0221 (13)	0.0274 (13)	0.0280 (13)	−0.0011 (11)	0.0007 (10)	−0.0001 (11)
C14	0.0208 (14)	0.050 (2)	0.0369 (15)	0.0010 (13)	0.0024 (11)	−0.0028 (14)
Cl2A	0.0254 (4)	0.0310 (4)	0.0442 (5)	0.0045 (4)	0.0099 (3)	−0.0034 (4)
Cl2B	0.035 (3)	0.075 (5)	0.052 (4)	−0.007 (3)	−0.006 (3)	−0.008 (3)
O4A	0.0232 (12)	0.0463 (15)	0.0276 (12)	0.0092 (11)	0.0026 (9)	0.0019 (11)
O4B	0.042 (9)	0.052 (10)	0.038 (8)	0.015 (7)	0.014 (6)	−0.002 (7)
O5	0.0323 (11)	0.0374 (12)	0.0253 (10)	−0.0003 (9)	−0.0035 (8)	−0.0036 (9)
O6	0.0261 (10)	0.0454 (14)	0.0276 (10)	0.0077 (9)	−0.0030 (8)	−0.0076 (9)
N2A	0.0168 (13)	0.0181 (12)	0.0306 (14)	0.0019 (10)	0.0016 (11)	0.0018 (10)
N2B	0.028 (6)	0.026 (6)	0.035 (6)	−0.007 (6)	0.006 (6)	0.002 (5)
C15A	0.018 (2)	0.0203 (18)	0.0416 (19)	0.0005 (15)	0.0085 (14)	0.0003 (14)
C15B	0.027 (5)	0.032 (5)	0.039 (5)	−0.005 (4)	0.003 (4)	0.001 (4)
C16A	0.0170 (16)	0.0282 (17)	0.0425 (18)	0.0013 (13)	0.0022 (13)	0.0041 (15)
C16B	0.020 (6)	0.026 (6)	0.046 (6)	−0.010 (6)	0.005 (6)	0.000 (5)
C17A	0.0223 (19)	0.038 (2)	0.0330 (19)	0.0007 (16)	−0.0021 (15)	0.0047 (16)
C17B	0.021 (6)	0.028 (6)	0.041 (6)	0.001 (5)	0.010 (5)	0.003 (6)
C18A	0.0191 (15)	0.0275 (16)	0.0295 (17)	0.0022 (13)	0.0063 (12)	0.0043 (13)
C18B	0.033 (7)	0.025 (6)	0.037 (7)	−0.003 (6)	0.008 (6)	0.001 (6)
C19A	0.0177 (18)	0.0164 (17)	0.0339 (17)	0.0006 (13)	0.0004 (14)	0.0033 (13)
C19B	0.026 (5)	0.027 (5)	0.033 (5)	−0.005 (5)	0.005 (5)	0.001 (5)
C20A	0.0224 (16)	0.0196 (15)	0.0309 (16)	−0.0016 (13)	0.0028 (12)	0.0001 (13)
C20B	0.022 (5)	0.025 (5)	0.039 (5)	−0.003 (5)	0.001 (5)	0.003 (5)
C21A	0.0232 (19)	0.0192 (16)	0.0275 (19)	−0.0009 (14)	0.0034 (15)	0.0023 (16)
C21B	0.031 (7)	0.030 (7)	0.038 (8)	−0.008 (6)	0.006 (7)	0.000 (7)
C22	0.0283 (15)	0.0166 (13)	0.0368 (15)	−0.0014 (11)	−0.0035 (11)	0.0040 (11)
C23	0.0329 (15)	0.0193 (13)	0.0315 (14)	−0.0044 (11)	−0.0087 (11)	0.0029 (11)
C24	0.0317 (13)	0.0186 (11)	0.0261 (12)	−0.0008 (12)	0.0016 (10)	−0.0001 (11)
C25	0.0247 (13)	0.0233 (14)	0.0299 (13)	0.0012 (12)	−0.0022 (10)	0.0022 (12)
C26	0.0286 (14)	0.0248 (14)	0.0260 (13)	0.0016 (12)	−0.0021 (10)	−0.0019 (11)
C27	0.0302 (15)	0.0216 (14)	0.0346 (15)	0.0004 (12)	0.0010 (12)	0.0011 (11)
C28	0.0357 (17)	0.049 (2)	0.0267 (15)	−0.0060 (15)	−0.0014 (12)	−0.0084 (14)

Geometric parameters (Å, º) top

Cl1—C1	1.746 (3)	O6—H6	0.8400
O1—H1	0.8400	O6—C25	1.361 (3)
O1—C4	1.371 (3)	N2A—C19A	1.414 (4)
O2—C10	1.371 (3)	N2A—C21A	1.279 (4)
O2—C14	1.432 (4)	N2B—C19B	1.407 (13)
O3—H3	0.8400	N2B—C21B	1.269 (12)
O3—C11	1.360 (3)	C15A—C16A	1.381 (5)
N1—C5	1.412 (3)	C15A—C20A	1.378 (4)
N1—C7	1.277 (4)	C15B—C16B	1.383 (10)
C1—C2	1.385 (4)	C15B—C20B	1.390 (10)
C1—C6	1.379 (4)	C16A—H16A	0.9500
C2—H2	0.9500	C16A—C17A	1.387 (5)
C2—C3	1.393 (4)	C16B—H16B	0.9500
C3—H3A	0.9500	C16B—C17B	1.386 (10)
C3—C4	1.381 (4)	C17A—H17A	0.9500
C4—C5	1.400 (4)	C17A—C18A	1.385 (5)
C5—C6	1.397 (4)	C17B—H17B	0.9500
C6—H6A	0.9500	C17B—C18B	1.387 (9)
C7—H7	0.9500	C18A—C19A	1.403 (4)
C7—C8	1.457 (4)	C18B—C19B	1.392 (9)
C8—C9	1.400 (4)	C19A—C20A	1.395 (4)
C8—C13	1.395 (4)	C19B—C20B	1.387 (9)
C9—H9	0.9500	C20A—H20A	0.9500
C9—C10	1.380 (4)	C20B—H20B	0.9500
C10—C11	1.403 (4)	C21A—H21A	0.9500
C11—C12	1.384 (4)	C21A—C22	1.470 (5)
C12—H12	0.9500	C21B—H21B	0.9500
C12—C13	1.389 (4)	C21B—C22	1.447 (13)
C13—H13	0.9500	C22—C23	1.406 (4)
C14—H14A	0.9800	C22—C27	1.388 (4)
C14—H14B	0.9800	C23—H23	0.9500
C14—H14C	0.9800	C23—C24	1.375 (4)
Cl2A—C15A	1.747 (4)	C24—C25	1.407 (3)
Cl2B—C15B	1.739 (11)	C25—C26	1.385 (4)
O4A—H4A	0.8400	C26—H26	0.9500
O4A—C18A	1.362 (4)	C26—C27	1.385 (4)
O4B—H4B	0.8400	C27—H27	0.9500
O4B—C18B	1.356 (12)	C28—H28A	0.9800
O5—C24	1.363 (3)	C28—H28B	0.9800
O5—C28	1.427 (3)	C28—H28C	0.9800

C4—O1—H1	109.5	C15A—C16A—C17A	118.3 (3)
C10—O2—C14	116.3 (2)	C17A—C16A—H16A	120.8
C11—O3—H3	109.5	C15B—C16B—H16B	119.9
C7—N1—C5	119.0 (2)	C15B—C16B—C17B	120.1 (16)
C2—C1—Cl1	119.4 (2)	C17B—C16B—H16B	119.9
C6—C1—Cl1	119.0 (2)	C16A—C17A—H17A	119.8
C6—C1—C2	121.6 (3)	C18A—C17A—C16A	120.4 (4)
C1—C2—H2	120.4	C18A—C17A—H17A	119.8
C1—C2—C3	119.3 (3)	C16B—C17B—H17B	120.5
C3—C2—H2	120.4	C16B—C17B—C18B	118.9 (15)
C2—C3—H3A	120.2	C18B—C17B—H17B	120.5
C4—C3—C2	119.5 (3)	O4A—C18A—C17A	119.1 (3)
C4—C3—H3A	120.2	O4A—C18A—C19A	120.4 (3)
O1—C4—C3	119.4 (2)	C17A—C18A—C19A	120.5 (3)
O1—C4—C5	119.4 (2)	O4B—C18B—C17B	118.5 (13)
C3—C4—C5	121.3 (3)	O4B—C18B—C19B	120.3 (12)
C4—C5—N1	116.1 (2)	C17B—C18B—C19B	121.2 (13)
C6—C5—N1	125.0 (2)	C18A—C19A—N2A	114.2 (3)
C6—C5—C4	118.7 (2)	C20A—C19A—N2A	126.7 (3)
C1—C6—C5	119.6 (2)	C20A—C19A—C18A	119.0 (3)
C1—C6—H6A	120.2	C18B—C19B—N2B	112.3 (13)
C5—C6—H6A	120.2	C20B—C19B—N2B	128.1 (13)
N1—C7—H7	118.4	C20B—C19B—C18B	119.5 (14)
N1—C7—C8	123.3 (3)	C15A—C20A—C19A	119.0 (3)
C8—C7—H7	118.4	C15A—C20A—H20A	120.5
C9—C8—C7	118.6 (2)	C19A—C20A—H20A	120.5
C13—C8—C7	122.2 (3)	C15B—C20B—H20B	120.4
C13—C8—C9	119.1 (2)	C19B—C20B—C15B	119.2 (15)
C8—C9—H9	119.5	C19B—C20B—H20B	120.4
C10—C9—C8	121.0 (3)	N2A—C21A—H21A	119.1
C10—C9—H9	119.5	N2A—C21A—C22	121.7 (4)
O2—C10—C9	125.6 (2)	C22—C21A—H21A	119.1
O2—C10—C11	115.0 (2)	N2B—C21B—H21B	128.8
C9—C10—C11	119.4 (2)	N2B—C21B—C22	102.4 (13)
O3—C11—C10	121.3 (2)	C22—C21B—H21B	128.8
O3—C11—C12	118.8 (2)	C23—C22—C21A	123.2 (3)
C12—C11—C10	119.9 (2)	C23—C22—C21B	98.7 (8)
C11—C12—H12	119.7	C27—C22—C21A	117.4 (3)
C11—C12—C13	120.6 (2)	C27—C22—C21B	141.7 (8)
C13—C12—H12	119.7	C27—C22—C23	119.4 (3)
C8—C13—H13	120.0	C22—C23—H23	120.0
C12—C13—C8	120.0 (3)	C24—C23—C22	120.1 (2)
C12—C13—H13	120.0	C24—C23—H23	120.0
O2—C14—H14A	109.5	O5—C24—C23	126.5 (2)
O2—C14—H14B	109.5	O5—C24—C25	113.5 (2)
O2—C14—H14C	109.5	C23—C24—C25	120.0 (3)
H14A—C14—H14B	109.5	O6—C25—C24	120.6 (2)
H14A—C14—H14C	109.5	O6—C25—C26	119.4 (2)
H14B—C14—H14C	109.5	C26—C25—C24	120.0 (2)
C18A—O4A—H4A	109.5	C25—C26—H26	120.1
C18B—O4B—H4B	109.5	C25—C26—C27	119.8 (3)
C24—O5—C28	116.6 (2)	C27—C26—H26	120.1
C25—O6—H6	109.5	C22—C27—H27	119.6
C21A—N2A—C19A	121.5 (3)	C26—C27—C22	120.7 (3)
C21B—N2B—C19B	114.5 (14)	C26—C27—H27	119.6
C16A—C15A—Cl2A	118.8 (3)	O5—C28—H28A	109.5
C20A—C15A—Cl2A	118.6 (3)	O5—C28—H28B	109.5
C20A—C15A—C16A	122.6 (3)	O5—C28—H28C	109.5
C16B—C15B—Cl2B	120.5 (11)	H28A—C28—H28B	109.5
C16B—C15B—C20B	120.9 (13)	H28A—C28—H28C	109.5
C20B—C15B—Cl2B	118.6 (11)	H28B—C28—H28C	109.5
C15A—C16A—H16A	120.8

Cl1—C1—C2—C3	−175.5 (2)	O6—C25—C26—C27	179.5 (3)
Cl1—C1—C6—C5	175.5 (2)	N2A—C19A—C20A—C15A	−176.7 (4)
O1—C4—C5—N1	−4.4 (4)	N2A—C21A—C22—C23	3.6 (5)
O1—C4—C5—C6	−179.3 (2)	N2A—C21A—C22—C27	−175.9 (3)
O2—C10—C11—O3	−1.8 (4)	N2B—C19B—C20B—C15B	178 (2)
O2—C10—C11—C12	178.0 (3)	N2B—C21B—C22—C23	−174.2 (16)
O3—C11—C12—C13	180.0 (3)	N2B—C21B—C22—C27	11 (3)
N1—C5—C6—C1	−174.6 (2)	C15A—C16A—C17A—C18A	0.8 (6)
N1—C7—C8—C9	−178.8 (3)	C15B—C16B—C17B—C18B	3 (4)
N1—C7—C8—C13	−2.4 (4)	C16A—C15A—C20A—C19A	−0.5 (6)
C1—C2—C3—C4	0.2 (4)	C16A—C17A—C18A—O4A	179.2 (3)
C2—C1—C6—C5	−1.2 (4)	C16A—C17A—C18A—C19A	−0.7 (6)
C2—C3—C4—O1	179.3 (3)	C16B—C15B—C20B—C19B	2 (4)
C2—C3—C4—C5	−1.6 (4)	C16B—C17B—C18B—O4B	−179 (2)
C3—C4—C5—N1	176.5 (3)	C16B—C17B—C18B—C19B	−1 (3)
C3—C4—C5—C6	1.5 (4)	C17A—C18A—C19A—N2A	177.5 (3)
C4—C5—C6—C1	−0.2 (4)	C17A—C18A—C19A—C20A	−0.1 (5)
C5—N1—C7—C8	173.2 (3)	C17B—C18B—C19B—N2B	−178.7 (18)
C6—C1—C2—C3	1.1 (4)	C17B—C18B—C19B—C20B	−1 (3)
C7—N1—C5—C4	152.0 (3)	C18A—C19A—C20A—C15A	0.6 (5)
C7—N1—C5—C6	−33.4 (4)	C18B—C19B—C20B—C15B	1 (3)
C7—C8—C9—C10	176.4 (3)	C19A—N2A—C21A—C22	177.3 (3)
C7—C8—C13—C12	−177.5 (3)	C19B—N2B—C21B—C22	−177.2 (15)
C8—C9—C10—O2	−178.0 (3)	C20A—C15A—C16A—C17A	−0.3 (6)
C8—C9—C10—C11	1.4 (4)	C20B—C15B—C16B—C17B	−4 (4)
C9—C8—C13—C12	−1.1 (4)	C21A—N2A—C19A—C18A	−178.0 (3)
C9—C10—C11—O3	178.8 (3)	C21A—N2A—C19A—C20A	−0.5 (6)
C9—C10—C11—C12	−1.4 (4)	C21A—C22—C23—C24	179.7 (3)
C10—C11—C12—C13	0.3 (4)	C21A—C22—C27—C26	−179.8 (3)
C11—C12—C13—C8	1.0 (4)	C21B—N2B—C19B—C18B	175 (2)
C13—C8—C9—C10	−0.1 (4)	C21B—N2B—C19B—C20B	−2 (3)
C14—O2—C10—C9	13.4 (4)	C21B—C22—C23—C24	−176.8 (11)
C14—O2—C10—C11	−166.0 (3)	C21B—C22—C27—C26	174.2 (17)
Cl2A—C15A—C16A—C17A	179.5 (3)	C22—C23—C24—O5	179.5 (3)
Cl2A—C15A—C20A—C19A	179.7 (3)	C22—C23—C24—C25	−0.1 (4)
Cl2B—C15B—C16B—C17B	174.7 (19)	C23—C22—C27—C26	0.7 (4)
Cl2B—C15B—C20B—C19B	−176.9 (18)	C23—C24—C25—O6	−179.7 (3)
O4A—C18A—C19A—N2A	−2.3 (5)	C23—C24—C25—C26	1.2 (4)
O4A—C18A—C19A—C20A	−179.9 (3)	C24—C25—C26—C27	−1.3 (4)
O4B—C18B—C19B—N2B	0 (3)	C25—C26—C27—C22	0.4 (4)
O4B—C18B—C19B—C20B	177 (2)	C27—C22—C23—C24	−0.8 (4)
O5—C24—C25—O6	0.7 (4)	C28—O5—C24—C23	4.9 (5)
O5—C24—C25—C26	−178.5 (3)	C28—O5—C24—C25	−175.5 (3)

Hydrogen-bond geometry (Å, º) top

Cg2 is the centroid of the C22–C27 ring.

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.84	2.21	2.695 (3)	116
O3—H3···O2	0.84	2.25	2.690 (3)	113
O4A—H4A···N2A	0.84	2.20	2.675 (4)	116
O6—H6···O5	0.84	2.18	2.645 (3)	115
O1—H1···O3ⁱ	0.84	2.26	2.854 (3)	128
O3—H3···O6ⁱⁱ	0.84	2.02	2.714 (3)	140
O6—H6···O1ⁱⁱⁱ	0.84	2.05	2.716 (3)	136
C2—H2···Cl2B^iv	0.95	2.71	3.449 (8)	135
C14—H14B···O4B^v	0.98	2.31	2.928 (16)	120
C28—H28C···O4A^vi	0.98	2.57	3.142 (4)	117
C7—H7···Cg2ⁱ	0.95	2.90	3.394 (3)	113

Symmetry codes: (i) −x, y−1/2, −z+1; (ii) x+1, y, z; (iii) −x−1, y+1/2, −z+1; (iv) x−1, y, z−1; (v) −x+1, y+1/2, −z+1; (vi) −x, y+1/2, −z+2.

Footnotes

‡Prof. Emerita.

Acknowledgements

We are grateful to the University of Constantine 1 for supporting this research. HSE is grateful to the University of Neuchâtel for their support over the years.

Funding information

Funding for this research was provided by: Algerian MESRS (Ministry of Higher Education and Scientific Research) and the Algerian DGRSDT (Directorate General for Scientific Research and Technological Development).

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