(E)-2-{[(2-Amino-phen-yl)imino]-meth-yl}-5-(benz-yl-oxy)phenol and (Z)-3-benz-yl-oxy-6-{[(5-chloro-2-hy-droxy-phen-yl)amino]-methyl-idene}cyclo-hexa-2,4-dien-1-one.

The title Schiff base compounds, C20H18N2O2 (I) and C20H16ClNO3 (II), were synthesized from 4-benz-yloxy-2-hy-droxy-benzaldehyde by reaction with 1,2-di-amino-benzene for (I), and condensation with 2-amino-4-chloro-phenol for (II). Compound (I) adopts the enol-imine tautomeric form with an E configuration about the C=N imine bond. In contrast, the o-hy-droxy Schiff base (II), is in the keto-imine tautomeric form with a Z configuration about the CH-NH bond. Neither mol-ecule is planar. In (I), the central benzene ring makes dihedral angles of 46.80 (10) and 78.19 (10)° with the outer phenyl-amine and phenyl rings, respectively, while for (II), the corresponding angles are 5.11 (9) and 58.42 (11)°, respectively. The mol-ecular structures of both compounds are affected by the formation of intra-molecular contacts, an O-H⋯N hydrogen bond for (I) and an N-H⋯O hydrogen bond for (II); each contact generates an S(6) ring motif. In the crystal of (I), strong N-H⋯O hydrogen bonds form zigzag chains of mol-ecules along the b-axis direction. Mol-ecules are further linked by C-H⋯π inter-actions and offset π-π contacts and these combine to form a three-dimensional network. The density functional theory (DFT) optimized structure of compound (II), at the B3LYP/6-311+G(d) level, confirmed that the keto tautomeric form of the compound, as found in the structure determination, is the lowest energy form. The anti-oxidant capacities of both compounds were determined by the cupric reducing anti-oxidant capacity (CUPRAC) process.

Chemical context

Schiff base compounds have been used as fine chemicals and medicinal substrates (Fun et al., 2011 ▸). Studies of the tautom­erism of Schiff bases (Alpaslan et al., 2011 ▸; Blagus et al., 2010 ▸; Ünver et al., 2002 ▸) have demonstrated that the stabilization of the keto–amino tautomer in the crystal depends mostly on the parent o-hydroxyl aldehyde, the type of the N-substituent, the electron withdrawing or donating of the N-substituent, its position and stereochemistry (Blagus et al., 2010 ▸). Schiff base compounds exhibit a broad range of biological activities, including anti­fungal and anti­bacterial (da Silva et al., 2011 ▸). They are used as anion sensors (Dalapati et al., 2011 ▸; Khalil et al., 2009 ▸), non-linear optical compounds (Sun et al., 2012 ▸), and as versatile ligands in coordination chemistry (Khanmohammadi et al., 2009 ▸; Keypour et al., 2010 ▸). In view of the inter­est in such materials we have synthesized the title compounds, (I) and (II), and report their crystal structures here. The common structural feature of these compounds is the presence of a benz­yloxy substituent on the central ring, although each mol­ecule adopts a different tautomeric form. Density functional theory (DFT) calculations on (II), carried out at the B3LYP/6-311+G(d) level, are compared with the experimentally determined mol­ecular structure and confirm that the keto tautomeric form of this compound, similar to that found in the structure determination, is the lowest energy form. The anti­oxidant capacity of both compounds was determined by the cupric reducing anti­oxidant capacity (CUPRAC) process.

Structural commentary

The mol­ecular structures of compounds (I) and (II), illus­trated in Figs. 1 ▸ and 2 ▸, respectively, are influenced by intra­molecular hydrogen bonds: the O—H⋯N hydrogen bond in (I) and the N—H⋯O contact in (II) (Tables 1 ▸ and 2 ▸) both form S(6) ring motifs. In compound (II), the N atom is protonated and the C9—O1 bond length, 1.277 (2) Å confirms this to be double bond. In compound (I), however, the C9=O1 bond length of 1.3498 (19) Å indicates a single bond. Bond C7=C8 [1.395 (3) Å] is a double bond in compound (II), whereas the corresponding bond in (I) [1.435 (3) Å] is a single bond. Compound (I) adopts the enol–imine tautomeric form and the configuration of the C7=N1 imine bond is E with a length of 1.288 (3) Å. In contrast the o-hy­droxy Schiff base of (II), has a Z configuration about the C7=C8 double bond and the mol­ecule adopts the keto–imine tautomeric form, with the N1—C7 bond length being 1.309 (2) Å. Neither mol­ecule is planar: in (I), the central ring (C8–C13) is inclined to the two outer rings (C1–C6 and C15–C20) by 46.80 (10) and 78.19 (10)°, respectively, while for (II), the dihedral angles between these rings are 5.11 (9) and 58.42 (11)°, respectively. In compound (II), the C1—N1—C7 angle is 127.15 (17)°.

Figure 1

The mol­ecular structure of compound (I), with the atom labelling. Displacement ellipsoids are drawn at the 50% probability level. The intra­molecular O—H⋯N hydrogen bond is shown as a dashed line.

Figure 2

The mol­ecular structure of compound (II), with the atom labeling. Displacement ellipsoids are drawn at the 50% probability level. The intra­molecular N—H⋯O hydrogen bond is shown as a dashed line.

Table 1

Hydrogen-bond geometry (Å, °) for (I)

Cg1 and Cg3 are the centroids of the C1–C6 and C15–C20 rings respectively.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1	0.82	1.90	2.629 (2)	147
N2—H2A⋯O2i	0.86	2.43	3.211 (3)	151
C14—H14B⋯Cg1ii	0.97	2.74	3.704 (3)	171
C16—H16⋯Cg1iii	0.93	2.96	3.792 (3)	150
C18—H18⋯Cg3iv	0.93	2.94	3.620 (2)	131

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) .

Table 2

Hydrogen-bond geometry (Å, °) for (II)

Cg3 is the centroid of the C15–C20 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O1	0.86 (2)	1.93 (2)	2.637 (2)	139 (2)
N1—H1⋯O2	0.86 (2)	2.27 (2)	2.620 (2)	104.5 (18)
O2—H2⋯O1i	0.80 (3)	1.84 (3)	2.619 (2)	165 (3)
C7—H7⋯Cl1ii	0.98 (2)	2.84 (2)	3.7971 (18)	164.5 (17)
C14—H14A⋯Cg3iii	0.97	2.71	3.569 (3)	148

Symmetry codes: (i) ; (ii) ; (iii) .

Supra­molecular features

In the crystal of (I), strong N2—H2A⋯O2i hydrogen bonds, Table 1 ▸, form zigzag chains of mol­ecules along the b-axis direction, Fig. 3 ▸. Weaker C—H⋯π and offset π–π stacking inter­actions also contribute to the packing (Fig. 4 ▸) [Cg2⋯Cg2(−x, y, −z + ) = 3.8151 (11) Å; Cg2 is the centroid of the central ring]. The overall crystal packing for this structure is shown in Fig. 5 ▸.

Figure 3

Zigzag chains of mol­ecules of (I) along the b-axis direction. Hydrogen bonds are drawn as blue dashed lines.

Figure 4

C—H⋯π and π–π conatcts (dotted green lines) in the crystal structure of (I).

Figure 5

Overall packing for (I) viewed along the b-axis direction.

For (II), strong O2—H2⋯O1i hydrogen bonds Table 2 ▸, form inversion dimers that enclose (18) rings. These combine with weaker C7—H7⋯Cl1 hydrogen bonds, which also generate inversion dimers but with (14) motifs. Inversion-related C14—H14A⋯Cg3ii contacts lead to the formation of sheets of mol­ecules parallel to (20), Fig. 6 ▸, which are stacked approximately along the b-axis direction. The overall packing for this structure is shown in Fig. 7 ▸.

Figure 6

Sheets of mol­ecules of (II) parallel to (20).

Figure 7

Overall packing for (II) viewed along the b-axis direction.

Database survey

A search of the Cambridge Database (Version 5.39, updated February 2018; Groom et al. 2016 ▸) for structures similar to (I) gave two hits, viz. (Z)-6-{2-[(E)-2,4-di­hydroxy­benzyl­idene­amino]­phenyl­amino­methyl­ene}-3-hy­droxy­cyclo­hexa-2,4-dien­one (Fun et al., 2008 ▸) and (E)-5-(benz­yloxy)-2-[(4-nitrophen­yl)carbonoimido­yl]phenol reported by us in 2015 (Ghichi et al., 2015 ▸). More recently, we have described the very similar structure of (E)-5-benz­yloxy-2-{[(4-chloro­phen­yl)imino]meth­yl}phenol (Ghichi et al., 2018 ▸). A search for analogues of (II) produced three related phenyl­ethyl­amino)­methyl­ene)cyclo­hexa-2,4-dien-1-ones (Chatziefthimiou et al., 2006 ▸) and our recent contribution also reported (E)-5-benz­yloxy-2-({[2-(1H-indol-3-yl)eth­yl]iminium­yl)meth­yl)phen­ol­ate, which is closely similar to (II). The structures of Schiff bases derived from hydroxyaryl aldehydes have been the subject of a general survey, in which a number of structural errors, often involving misplaced H atoms, were pointed out (Blagus et al., 2010 ▸).

DFT-optimized calculations

DFT quantum chemical calculations were performed on mol­ecule (II) using the hybrid functional B3LYP (Becke et al., 1993 ▸; Lee et al., 1988 ▸), and base 6–311+G (d). The DFT structure optimization of (II) was performed starting from the X-ray geometry. The DFT and X-ray stuctures are compared in Fig. 8 ▸. The calculated values of bond lengths (Table 3 ▸) compare well with experimental values with the largest bond-length deviation being less than 0.031 Å from those found in the crystal structure. The adoption of the keto–imine tautomeric form is also predicted by these calculations. The study also shows that the HOMO and LUMO are localized in the plane extending from the chloro­hydroxy­benzene ring to the central phenol ring. The electron distribution of the HOMO-1, HOMO, LUMO and LUMO+1 energy levels is shown in Fig. 9 ▸. The occupied orbitals are predominantly of σ-character as is the LUMO, while LUMO+1 is mainly of π-character. The HOMO–LUMO gap is 0.12449 a.u, with frontier mol­ecular orbital energies, E HOMO and ELUMO of −5.622 and −2.234 eV, respectively.

Figure 8

Comparison of the structures of (II) obtained from (a) the X-ray determination and (b) the DFT calculations.

Table 3

Experimental and calculated bond lengths (Å) for compound (II)

Bond	X-ray	B3LYP/6–311+G(d)
N1—C1	1.406 (2)	1.399
N1—C7	1.309 (2)	1.340
O1—C9	1.277 (2)	1.254
O2—C2	1.351 (2)	1.364
O3—C11	1.363 (2)	1.355
O3—C14	1.432 (3)	1.439
C1—C2	1.403 (2)	1.410
C1—C6	1.389 (2)	1.398
C2—C3	1.384 (3)	1.389
C3—C4	1.381 (3)	1.394
C5—C11	1.742 (2)	1.759
C7—C8	1.395 (3)	1.385
C9—C10	1.418 (3)	1.411
C10—C11	1.373 (3)	1.373
C12—C13	1.350 (3)	1.358
C14—C15	1.504 (3)	1.504
C16—C17	1.392 (4)	1.393
C19—C20	1.387 (3)	1.393

Figure 9

Electron distribution in the HOMO-1, HOMO, LUMO and LUMO-1 energy levels for (II).

Anti­oxidant activity

The anti­oxidant activity profiles of (I) and (II) were determined using the copper(II)–neocuprine [CuII–Nc] (CUPRAC) process (Apak et al., 2004 ▸). The CUPRAC method (cupric ion reducing anti­oxidant capacity) follows the variation in the absorbance of the neocuproine (2,9-dimethyl-1,10-phenanthroline, Nc), copper+2 complex Nc2–Cu+2 In the presence of an anti­oxidant, the copper–neocuproine complex is reduced and this reaction is followed and qu­anti­fied spectrophotometrically at a wavelength of 450 nm. The results indicate that the percentage (%) inhibition (IC50) in the CUPRAC assay is small for both compounds in comparison to that for butyl­ated hy­droxy­toluene (BHT) that was used as a positive control. In Table 4 ▸ the values shown are the means of three separate measurements.

Table 4

Cupric ion reducing anti­oxidant capacity of compounds (I) and (II)

	Percentage (%) Inhibition
	3.125 µg	6.25 µg	12.5 µg	25 µg	50 µg	100 µg	200 µg	A0.50 (μg/ml)
Compound (I)	0.28±0.01	0.46±0.00	0.76±0.03	1.55±0.04	2.60±0.14	3.81±0.15	4.33±0.04	7.4±0.21
Compound (II)	0.30±0.00	0.46±0.01	0.78±0.01	1.12±0.07	1.84±0.19	2.34±0.12	4.39±0.04	6.10±0.26
BHT	0.19±0.01	0.33±0.04	0.66±0.07	1.03±0.07	1.48±0.09	2.04±0.14	2.32±0.28	9.62±0.87

Synthesis and crystallization

Compound (I)

1,2-Di­amino­benzene (1 equiv.) and 4-benz­yloxy-2-hy­droxy­benzaldehyde (1 equiv.) in ethanol (15–20 ml) were refluxed for 1 h, the solvent was evaporated in vacuo. The residue was recrystallized from ethanol, yielding yellow block-like crystals on slow evaporation of the solvent. The purity of the compound was determined from its NMR spectrum (250 MHz, CDCl3). The azomethine proton appears in the 8.5–8.6 p.p.m.range, while the imine bond is characterized in the 13C NMR spectrum with the imine C and the C atom bound to the OH group appearing in the 161.58–163.20 p.p.m.range. 1H NMR: δ = 6.6–7.6 (m, 12H; H-ar), δ = 13.5 (s, 1H; OH), δ = 4 (s, 1H; NH), δ = 5.1 (s, 1H; CH–O). 13C NMR: 70.22, 127.66, 127.73, 128.32, 128.8, 140.66, 161.58, 163.02, 163.2.

Compound (II)

2-Amino-4-chloro­yphenol (1 equiv.) and 4-benz­yloxy-2-hy­droxy­benzaldehyde (1 equiv.) in ethanol (20 ml) were refluxed for 30–60 min, the solvent was evaporated in vacuo. The residue was recrystallized from ethanol, yielding orange block-like crystals on slow evaporation of the solvent. The purity of the compound was detemined by its NMR spectrum (250 MHz, CDCl3). 1H NMR: δ = 6.5–7.7 (m, 11H; H-ar), δ = 8.5–8.6 (s, 1H; OH), δ = 5.1 (s, 1H; CH–O). 13C NMR: 55.6, 128.2, 128.7, 133.3, 136.4, 141.4, 159.69, 162.82, 163.77.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 5 ▸. In compound (I), the hydroxyl H atom was located in a difference-Fourier map and initially freely refined. In the final cycles of refinements it was positioned geometrically (O—H = 0.82 Å) and refined with U iso(H) = 1.5U eq(O). In compound (II), the H atoms on N1, C7 and O2 were located in a difference-Fourier and refined freely. For both compounds, the other C-bound H atoms were positioned geometrically (C—H = 0.97–0.97 Å) and refined as riding with U iso(H) = 1.2U eq(C).

Table 5

Experimental details

	(I)	(II)
Crystal data
Chemical formula	C20H18N2O2	C20H16ClNO3
M r	318.36	353.79
Crystal system, space group	Monoclinic, C2/c	Triclinic, P
Temperature (K)	293	293
a, b, c (Å)	35.1343 (12), 7.2564 (2), 13.1450 (5)	5.9590 (2), 7.8710 (3), 17.9743 (6)
α, β, γ (°)	90, 95.553 (2), 90	98.381 (2), 93.817 (2), 90.294 (2)
V (Å3)	3335.57 (19)	832.11 (5)
Z	8	2
Radiation type	Mo Kα	Mo Kα
μ (mm−1)	0.08	0.25
Crystal size (mm)	0.03 × 0.02 × 0.01	0.03 × 0.02 × 0.01
Data collection
Diffractometer	Bruker APEXII CCD	Bruker APEXII CCD
No. of measured, independent and observed [I > 2σ(I)] reflections	18218, 3811, 1915	13513, 3052, 2490
R int	0.072	0.025
(sin θ/λ)max (Å−1)	0.650	0.606
Refinement
R[F 2 > 2σ(F 2)], wR(F 2), S	0.049, 0.134, 1.00	0.042, 0.133, 1.10
No. of reflections	3811	3052
No. of parameters	221	238
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement	H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)	0.17, −0.15	0.21, −0.21

Computer programs: APEX2 and SAINT (Bruker, 2012 ▸), SHELXS97 and SHELXTL (Sheldrick, 2008 ▸) and SHELXL2017 (Sheldrick, 2015 ▸).

Crystal structure: contains datablock(s) global, I, II. DOI: 10.1107/S2056989018005662/sj5553sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989018005662/sj5553Isup2.hkl

Structure factors: contains datablock(s) II. DOI: 10.1107/S2056989018005662/sj5553IIsup3.hkl

Click here for additional data file.

Supporting information file. DOI: 10.1107/S2056989018005662/sj5553Isup4.cml

Click here for additional data file.

Supporting information file. DOI: 10.1107/S2056989018005662/sj5553IIsup5.cml

CCDC references: 1836250, 1836249

Additional supporting information: crystallographic information; 3D view; checkCIF report

C20H18N2O2	F(000) = 1344
Mr = 318.36	Dx = 1.268 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 35.1343 (12) Å	Cell parameters from 1907 reflections
b = 7.2564 (2) Å	θ = 2.9–21.9°
c = 13.1450 (5) Å	µ = 0.08 mm−1
β = 95.553 (2)°	T = 293 K
V = 3335.57 (19) Å3	Block, yellow
Z = 8	0.03 × 0.02 × 0.01 mm

Bruker APEXII CCD diffractometer	Rint = 0.072
Detector resolution: 18.4 pixels mm-1	θmax = 27.5°, θmin = 3.4°
φ and ω scans	h = −45→45
18218 measured reflections	k = −9→9
3811 independent reflections	l = −16→17
1915 reflections with I > 2σ(I)

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)] = 0.049	Hydrogen site location: mixed
wR(F2) = 0.134	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	w = 1/[σ2(Fo2) + (0.0527P)2 + 0.5669P] where P = (Fo2 + 2Fc2)/3
3811 reflections	(Δ/σ)max = 0.001
221 parameters	Δρmax = 0.17 e Å−3
0 restraints	Δρmin = −0.15 e Å−3

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles

	x	y	z	Uiso*/Ueq
O1	0.00836 (4)	−0.03108 (16)	0.12180 (11)	0.0578 (5)
O2	0.10314 (4)	0.43746 (16)	0.17382 (10)	0.0513 (5)
N1	−0.06331 (5)	0.0754 (2)	0.08936 (12)	0.0477 (6)
N2	−0.09669 (6)	−0.1879 (3)	0.19901 (17)	0.0913 (9)
C1	−0.10273 (6)	0.0392 (2)	0.06599 (15)	0.0458 (7)
C2	−0.12530 (6)	0.1274 (3)	−0.01145 (17)	0.0529 (8)
C3	−0.16347 (7)	0.0816 (3)	−0.03355 (19)	0.0653 (9)
C4	−0.17934 (7)	−0.0518 (3)	0.0237 (2)	0.0708 (10)
C5	−0.15720 (7)	−0.1400 (3)	0.1008 (2)	0.0683 (10)
C6	−0.11880 (6)	−0.1003 (3)	0.12233 (17)	0.0553 (8)
C7	−0.05090 (6)	0.2425 (3)	0.09311 (14)	0.0436 (7)
C8	−0.01110 (5)	0.2870 (2)	0.11319 (14)	0.0396 (6)
C9	0.01726 (6)	0.1499 (2)	0.12587 (14)	0.0411 (7)
C10	0.05547 (6)	0.1960 (2)	0.14368 (15)	0.0452 (7)
C11	0.06603 (5)	0.3795 (2)	0.15199 (14)	0.0410 (6)
C12	0.03863 (6)	0.5185 (2)	0.13959 (14)	0.0431 (7)
C13	0.00105 (6)	0.4708 (2)	0.12065 (14)	0.0421 (7)
C14	0.13205 (6)	0.2969 (3)	0.18376 (19)	0.0617 (9)
C15	0.16990 (6)	0.3854 (2)	0.21507 (18)	0.0490 (7)
C16	0.18486 (7)	0.3842 (3)	0.3151 (2)	0.0623 (9)
C17	0.22001 (7)	0.4634 (3)	0.3441 (2)	0.0693 (10)
C18	0.24053 (7)	0.5423 (3)	0.2725 (2)	0.0698 (10)
C19	0.22599 (7)	0.5434 (3)	0.1723 (2)	0.0715 (10)
C20	0.19090 (6)	0.4654 (3)	0.14359 (19)	0.0617 (9)
H1	−0.01490	−0.04310	0.11149	0.0870*
H2	−0.11464	0.21904	−0.04924	0.0640*
H2A	−0.10663	−0.27019	0.23540	0.1100*
H2B	−0.07285	−0.16065	0.21082	0.1100*
H3	−0.17822	0.14023	−0.08652	0.0780*
H4	−0.20504	−0.08226	0.01022	0.0850*
H5	−0.16836	−0.22861	0.13952	0.0820*
H7	−0.0691 (5)	0.349 (3)	0.0810 (13)	0.045 (5)*
H10	0.07401	0.10419	0.15006	0.0540*
H12	0.04583	0.64178	0.14416	0.0520*
H13	−0.01720	0.56385	0.11238	0.0510*
H14A	0.12613	0.20744	0.23476	0.0740*
H14B	0.13296	0.23331	0.11913	0.0740*
H16	0.17121	0.32937	0.36425	0.0750*
H17	0.22971	0.46292	0.41244	0.0830*
H18	0.26425	0.59506	0.29182	0.0840*
H19	0.23986	0.59698	0.12325	0.0860*
H20	0.18125	0.46665	0.07518	0.0740*

	U11	U22	U33	U12	U13	U23
O1	0.0526 (9)	0.0348 (7)	0.0852 (11)	−0.0032 (6)	0.0022 (8)	0.0001 (6)
O2	0.0397 (9)	0.0389 (7)	0.0745 (10)	0.0008 (6)	0.0021 (7)	−0.0048 (6)
N1	0.0457 (11)	0.0460 (10)	0.0507 (11)	−0.0054 (7)	0.0018 (8)	0.0016 (7)
N2	0.0912 (17)	0.0807 (15)	0.0962 (17)	−0.0325 (12)	−0.0211 (13)	0.0422 (12)
C1	0.0440 (13)	0.0420 (11)	0.0509 (13)	−0.0023 (9)	0.0028 (10)	−0.0036 (9)
C2	0.0527 (15)	0.0473 (11)	0.0581 (14)	0.0000 (9)	0.0020 (11)	0.0007 (10)
C3	0.0532 (16)	0.0590 (14)	0.0801 (18)	0.0082 (11)	−0.0113 (13)	−0.0071 (12)
C4	0.0454 (15)	0.0639 (15)	0.102 (2)	−0.0072 (11)	0.0012 (14)	−0.0144 (14)
C5	0.0598 (17)	0.0602 (14)	0.0848 (19)	−0.0201 (11)	0.0058 (14)	0.0032 (12)
C6	0.0544 (15)	0.0470 (12)	0.0633 (15)	−0.0100 (10)	−0.0002 (12)	0.0042 (10)
C7	0.0474 (13)	0.0430 (11)	0.0403 (12)	0.0003 (9)	0.0041 (9)	0.0017 (8)
C8	0.0417 (12)	0.0403 (10)	0.0365 (11)	−0.0009 (8)	0.0027 (9)	0.0003 (8)
C9	0.0476 (13)	0.0347 (10)	0.0411 (12)	−0.0006 (8)	0.0056 (10)	−0.0004 (8)
C10	0.0434 (13)	0.0369 (10)	0.0553 (13)	0.0036 (8)	0.0043 (10)	−0.0015 (9)
C11	0.0401 (12)	0.0418 (10)	0.0415 (11)	−0.0024 (8)	0.0056 (9)	−0.0018 (8)
C12	0.0471 (13)	0.0344 (10)	0.0472 (12)	−0.0014 (8)	0.0021 (10)	−0.0014 (8)
C13	0.0457 (13)	0.0380 (10)	0.0422 (12)	0.0044 (8)	0.0021 (9)	0.0006 (8)
C14	0.0454 (14)	0.0441 (12)	0.0954 (19)	0.0041 (9)	0.0055 (12)	−0.0047 (11)
C15	0.0398 (13)	0.0381 (10)	0.0683 (15)	0.0037 (8)	0.0017 (11)	0.0001 (9)
C16	0.0557 (16)	0.0601 (14)	0.0720 (18)	0.0053 (11)	0.0111 (13)	0.0067 (11)
C17	0.0664 (18)	0.0707 (15)	0.0673 (17)	0.0101 (13)	−0.0113 (14)	−0.0064 (12)
C18	0.0473 (15)	0.0571 (14)	0.102 (2)	−0.0037 (11)	−0.0074 (15)	−0.0060 (13)
C19	0.0623 (17)	0.0643 (15)	0.088 (2)	−0.0158 (12)	0.0079 (15)	0.0094 (13)
C20	0.0618 (16)	0.0554 (13)	0.0668 (16)	−0.0088 (11)	0.0014 (13)	0.0057 (11)

O1—C9	1.3498 (19)	C14—C15	1.498 (3)
O2—C11	1.374 (2)	C15—C20	1.378 (3)
O2—C14	1.437 (3)	C15—C16	1.368 (3)
N1—C1	1.414 (3)	C16—C17	1.382 (3)
N1—C7	1.288 (3)	C17—C18	1.366 (4)
O1—H1	0.8200	C18—C19	1.366 (4)
N2—C6	1.368 (3)	C19—C20	1.376 (3)
C1—C2	1.385 (3)	C2—H2	0.9300
C1—C6	1.405 (3)	C3—H3	0.9300
N2—H2A	0.8600	C4—H4	0.9300
N2—H2B	0.8600	C5—H5	0.9300
C2—C3	1.385 (3)	C7—H7	1.01 (2)
C3—C4	1.377 (3)	C10—H10	0.9300
C4—C5	1.375 (4)	C12—H12	0.9300
C5—C6	1.382 (3)	C13—H13	0.9300
C7—C8	1.435 (3)	C14—H14A	0.9700
C8—C9	1.407 (2)	C14—H14B	0.9700
C8—C13	1.401 (2)	C16—H16	0.9300
C9—C10	1.381 (3)	C17—H17	0.9300
C10—C11	1.384 (2)	C18—H18	0.9300
C11—C12	1.393 (2)	C19—H19	0.9300
C12—C13	1.364 (3)	C20—H20	0.9300
C11—O2—C14	116.75 (13)	C17—C18—C19	119.6 (2)
C1—N1—C7	120.27 (16)	C18—C19—C20	120.3 (2)
C9—O1—H1	109.00	C15—C20—C19	120.7 (2)
N1—C1—C2	123.57 (17)	C1—C2—H2	119.00
C2—C1—C6	119.33 (19)	C3—C2—H2	119.00
N1—C1—C6	117.04 (17)	C2—C3—H3	120.00
H2A—N2—H2B	120.00	C4—C3—H3	120.00
C6—N2—H2B	120.00	C3—C4—H4	120.00
C1—C2—C3	121.1 (2)	C5—C4—H4	120.00
C6—N2—H2A	120.00	C4—C5—H5	119.00
C2—C3—C4	119.3 (2)	C6—C5—H5	119.00
C3—C4—C5	120.0 (2)	N1—C7—H7	120.6 (11)
C4—C5—C6	121.7 (2)	C8—C7—H7	116.7 (11)
N2—C6—C5	121.8 (2)	C9—C10—H10	120.00
C1—C6—C5	118.5 (2)	C11—C10—H10	120.00
N2—C6—C1	119.7 (2)	C11—C12—H12	121.00
N1—C7—C8	122.64 (19)	C13—C12—H12	121.00
C7—C8—C9	121.96 (15)	C8—C13—H13	119.00
C7—C8—C13	120.81 (17)	C12—C13—H13	119.00
C9—C8—C13	117.23 (17)	O2—C14—H14A	110.00
O1—C9—C10	117.38 (16)	O2—C14—H14B	110.00
C8—C9—C10	120.97 (14)	C15—C14—H14A	110.00
O1—C9—C8	121.65 (17)	C15—C14—H14B	110.00
C9—C10—C11	119.68 (16)	H14A—C14—H14B	108.00
C10—C11—C12	120.70 (17)	C15—C16—H16	120.00
O2—C11—C10	123.57 (15)	C17—C16—H16	120.00
O2—C11—C12	115.72 (14)	C16—C17—H17	120.00
C11—C12—C13	118.90 (14)	C18—C17—H17	120.00
C8—C13—C12	122.50 (16)	C17—C18—H18	120.00
O2—C14—C15	108.77 (16)	C19—C18—H18	120.00
C14—C15—C16	120.6 (2)	C18—C19—H19	120.00
C14—C15—C20	120.9 (2)	C20—C19—H19	120.00
C16—C15—C20	118.5 (2)	C15—C20—H20	120.00
C15—C16—C17	120.8 (2)	C19—C20—H20	120.00
C16—C17—C18	120.1 (2)
C14—O2—C11—C10	2.8 (3)	C13—C8—C9—O1	178.84 (17)
C14—O2—C11—C12	−178.09 (17)	C13—C8—C9—C10	−0.8 (3)
C11—O2—C14—C15	−175.82 (17)	C7—C8—C13—C12	−179.96 (18)
C7—N1—C1—C2	44.0 (3)	C9—C8—C13—C12	−0.1 (3)
C7—N1—C1—C6	−139.06 (19)	O1—C9—C10—C11	−177.83 (17)
C1—N1—C7—C8	−177.94 (17)	C8—C9—C10—C11	1.8 (3)
N1—C1—C2—C3	177.54 (19)	C9—C10—C11—O2	177.20 (17)
C6—C1—C2—C3	0.6 (3)	C9—C10—C11—C12	−1.9 (3)
N1—C1—C6—N2	3.0 (3)	O2—C11—C12—C13	−178.16 (16)
N1—C1—C6—C5	−179.52 (19)	C10—C11—C12—C13	1.0 (3)
C2—C1—C6—N2	−179.9 (2)	C11—C12—C13—C8	0.0 (3)
C2—C1—C6—C5	−2.4 (3)	O2—C14—C15—C16	99.2 (2)
C1—C2—C3—C4	1.1 (3)	O2—C14—C15—C20	−82.5 (2)
C2—C3—C4—C5	−1.0 (4)	C14—C15—C16—C17	179.1 (2)
C3—C4—C5—C6	−0.8 (4)	C20—C15—C16—C17	0.8 (3)
C4—C5—C6—N2	−180.0 (2)	C14—C15—C20—C19	−178.73 (19)
C4—C5—C6—C1	2.5 (3)	C16—C15—C20—C19	−0.4 (3)
N1—C7—C8—C9	2.8 (3)	C15—C16—C17—C18	−0.8 (3)
N1—C7—C8—C13	−177.43 (18)	C16—C17—C18—C19	0.4 (3)
C7—C8—C9—O1	−1.4 (3)	C17—C18—C19—C20	−0.1 (3)
C7—C8—C9—C10	179.05 (18)	C18—C19—C20—C15	0.1 (3)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.82	1.90	2.629 (2)	147
N2—H2A···O2i	0.86	2.43	3.211 (3)	151
C14—H14B···Cg1ii	0.97	2.74	3.704 (3)	171
C16—H16···Cg1iii	0.93	2.96	3.792 (3)	150
C18—H18···Cg3iv	0.93	2.94	3.620 (2)	131

C20H16ClNO3	Z = 2
Mr = 353.79	F(000) = 368
Triclinic, P1	Dx = 1.412 Mg m−3
a = 5.9590 (2) Å	Mo Kα radiation, λ = 0.71073 Å
b = 7.8710 (3) Å	Cell parameters from 5281 reflections
c = 17.9743 (6) Å	θ = 2.7–30.7°
α = 98.381 (2)°	µ = 0.25 mm−1
β = 93.817 (2)°	T = 293 K
γ = 90.294 (2)°	Block, orange
V = 832.11 (5) Å3	0.03 × 0.02 × 0.01 mm

Bruker APEXII CCD diffractometer	Rint = 0.025
Detector resolution: 18.4 pixels mm-1	θmax = 25.5°, θmin = 2.6°
φ and ω scans	h = −6→7
13513 measured reflections	k = −9→9
3052 independent reflections	l = −21→21
2490 reflections with I > 2σ(I)

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)] = 0.042	Hydrogen site location: mixed
wR(F2) = 0.133	H atoms treated by a mixture of independent and constrained refinement
S = 1.10	w = 1/[σ2(Fo2) + (0.0727P)2 + 0.2078P] where P = (Fo2 + 2Fc2)/3
3052 reflections	(Δ/σ)max < 0.001
238 parameters	Δρmax = 0.21 e Å−3
0 restraints	Δρmin = −0.21 e Å−3

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell esds are taken into account in the estimation of distances, angles and torsion angles

	x	y	z	Uiso*/Ueq
Cl1	0.93492 (8)	0.93423 (7)	−0.13197 (3)	0.0533 (2)
O1	0.1309 (2)	0.6289 (2)	0.14736 (7)	0.0518 (5)
O2	0.1581 (3)	0.5583 (2)	−0.05318 (9)	0.0546 (5)
O3	0.3158 (2)	0.7742 (2)	0.41212 (7)	0.0520 (5)
N1	0.4214 (3)	0.7241 (2)	0.05641 (8)	0.0382 (5)
C1	0.4780 (3)	0.7305 (2)	−0.01782 (10)	0.0348 (5)
C2	0.3343 (3)	0.6417 (2)	−0.07572 (10)	0.0381 (6)
C3	0.3805 (3)	0.6429 (3)	−0.15011 (10)	0.0444 (6)
C4	0.5643 (3)	0.7329 (3)	−0.16776 (10)	0.0433 (6)
C5	0.7028 (3)	0.8202 (2)	−0.11011 (10)	0.0374 (6)
C6	0.6635 (3)	0.8205 (2)	−0.03551 (10)	0.0371 (5)
C7	0.5388 (3)	0.7860 (2)	0.11873 (10)	0.0394 (6)
C8	0.4718 (3)	0.7766 (2)	0.19092 (10)	0.0380 (5)
C9	0.2627 (3)	0.6945 (2)	0.20317 (10)	0.0380 (5)
C10	0.2119 (3)	0.6906 (3)	0.27886 (10)	0.0426 (6)
C11	0.3535 (3)	0.7669 (3)	0.33778 (10)	0.0409 (6)
C12	0.5562 (3)	0.8502 (3)	0.32557 (11)	0.0481 (7)
C13	0.6123 (3)	0.8526 (3)	0.25418 (11)	0.0465 (6)
C14	0.1117 (4)	0.6974 (3)	0.43003 (11)	0.0572 (8)
C15	0.1044 (4)	0.7217 (3)	0.51439 (10)	0.0474 (7)
C16	−0.0740 (4)	0.8010 (3)	0.54911 (14)	0.0632 (8)
C17	−0.0843 (5)	0.8143 (3)	0.62686 (15)	0.0719 (9)
C18	0.0817 (5)	0.7470 (3)	0.66975 (12)	0.0631 (8)
C19	0.2599 (5)	0.6690 (4)	0.63599 (13)	0.0677 (9)
C20	0.2723 (4)	0.6576 (3)	0.55862 (12)	0.0621 (8)
H1	0.299 (4)	0.674 (3)	0.0639 (13)	0.057 (7)*
H2	0.080 (5)	0.509 (4)	−0.0877 (18)	0.086 (10)*
H3	0.28678	0.58262	−0.18855	0.0530*
H4	0.59415	0.73465	−0.21778	0.0520*
H6	0.75959	0.88004	0.00245	0.0450*
H7	0.686 (4)	0.840 (3)	0.1147 (11)	0.043 (5)*
H10	0.08097	0.63559	0.28872	0.0510*
H12	0.64933	0.90248	0.36612	0.0580*
H13	0.74667	0.90542	0.24615	0.0560*
H14A	0.10695	0.57595	0.41018	0.0690*
H14B	−0.01698	0.75127	0.40768	0.0690*
H16	−0.18852	0.84600	0.52046	0.0760*
H17	−0.20480	0.86928	0.64988	0.0860*
H18	0.07282	0.75461	0.72159	0.0760*
H19	0.37329	0.62325	0.66483	0.0810*
H20	0.39585	0.60591	0.53619	0.0740*

	U11	U22	U33	U12	U13	U23
Cl1	0.0448 (3)	0.0693 (4)	0.0476 (3)	−0.0148 (2)	0.0136 (2)	0.0105 (2)
O1	0.0473 (8)	0.0697 (10)	0.0352 (7)	−0.0287 (7)	−0.0005 (6)	−0.0002 (6)
O2	0.0469 (8)	0.0723 (11)	0.0437 (8)	−0.0303 (8)	−0.0049 (7)	0.0105 (7)
O3	0.0513 (8)	0.0735 (10)	0.0313 (7)	−0.0160 (7)	0.0047 (6)	0.0075 (6)
N1	0.0356 (8)	0.0456 (9)	0.0330 (8)	−0.0118 (7)	0.0042 (6)	0.0039 (6)
C1	0.0346 (9)	0.0376 (9)	0.0323 (9)	−0.0039 (7)	0.0041 (7)	0.0046 (7)
C2	0.0340 (9)	0.0399 (10)	0.0397 (10)	−0.0075 (8)	−0.0029 (8)	0.0066 (7)
C3	0.0469 (11)	0.0494 (11)	0.0349 (10)	−0.0082 (9)	−0.0067 (8)	0.0037 (8)
C4	0.0487 (11)	0.0505 (11)	0.0310 (9)	−0.0036 (9)	0.0038 (8)	0.0068 (8)
C5	0.0340 (9)	0.0404 (10)	0.0385 (10)	−0.0029 (8)	0.0062 (7)	0.0066 (7)
C6	0.0343 (9)	0.0421 (10)	0.0335 (9)	−0.0077 (8)	0.0011 (7)	0.0017 (7)
C7	0.0352 (10)	0.0454 (11)	0.0373 (10)	−0.0108 (8)	0.0025 (8)	0.0052 (8)
C8	0.0353 (9)	0.0440 (10)	0.0345 (9)	−0.0087 (8)	0.0025 (7)	0.0051 (7)
C9	0.0370 (9)	0.0407 (10)	0.0352 (9)	−0.0089 (8)	0.0021 (7)	0.0028 (7)
C10	0.0388 (10)	0.0513 (11)	0.0379 (10)	−0.0134 (8)	0.0057 (8)	0.0063 (8)
C11	0.0426 (10)	0.0484 (11)	0.0321 (9)	−0.0043 (8)	0.0034 (8)	0.0068 (8)
C12	0.0414 (11)	0.0641 (13)	0.0370 (10)	−0.0152 (9)	−0.0041 (8)	0.0047 (9)
C13	0.0376 (10)	0.0631 (13)	0.0380 (10)	−0.0178 (9)	0.0004 (8)	0.0066 (9)
C14	0.0551 (13)	0.0804 (16)	0.0358 (10)	−0.0195 (11)	0.0051 (9)	0.0072 (10)
C15	0.0520 (12)	0.0559 (12)	0.0340 (10)	−0.0134 (9)	0.0084 (9)	0.0035 (8)
C16	0.0670 (15)	0.0686 (15)	0.0584 (14)	0.0097 (12)	0.0141 (12)	0.0195 (11)
C17	0.0911 (19)	0.0635 (15)	0.0647 (15)	0.0071 (14)	0.0405 (15)	0.0050 (12)
C18	0.0877 (18)	0.0656 (15)	0.0342 (10)	−0.0144 (13)	0.0125 (11)	−0.0020 (10)
C19	0.0683 (16)	0.0918 (19)	0.0397 (12)	−0.0086 (14)	−0.0080 (11)	0.0046 (11)
C20	0.0496 (13)	0.0896 (18)	0.0434 (12)	0.0007 (12)	0.0051 (10)	−0.0033 (11)

Cl1—C5	1.7423 (18)	C14—C15	1.504 (3)
O1—C9	1.277 (2)	C15—C20	1.380 (3)
O2—C2	1.351 (2)	C15—C16	1.375 (3)
O3—C11	1.363 (2)	C16—C17	1.392 (4)
O3—C14	1.432 (3)	C17—C18	1.370 (4)
N1—C1	1.406 (2)	C18—C19	1.363 (4)
N1—C7	1.309 (2)	C19—C20	1.387 (3)
O2—H2	0.80 (3)	C3—H3	0.9300
C1—C2	1.403 (2)	C4—H4	0.9300
C1—C6	1.389 (2)	C6—H6	0.9300
N1—H1	0.86 (2)	C7—H7	0.98 (2)
C2—C3	1.384 (3)	C10—H10	0.9300
C3—C4	1.381 (3)	C12—H12	0.9300
C4—C5	1.378 (3)	C13—H13	0.9300
C5—C6	1.376 (3)	C14—H14A	0.9700
C7—C8	1.395 (3)	C14—H14B	0.9700
C8—C13	1.422 (3)	C16—H16	0.9300
C8—C9	1.445 (2)	C17—H17	0.9300
C9—C10	1.418 (3)	C18—H18	0.9300
C10—C11	1.373 (3)	C19—H19	0.9300
C11—C12	1.416 (3)	C20—H20	0.9300
C12—C13	1.350 (3)
C11—O3—C14	117.35 (14)	C15—C16—C17	120.4 (2)
C1—N1—C7	127.15 (17)	C16—C17—C18	120.5 (2)
C2—O2—H2	113 (2)	C17—C18—C19	119.6 (2)
N1—C1—C6	123.47 (16)	C18—C19—C20	120.1 (2)
C2—C1—C6	119.86 (16)	C15—C20—C19	121.1 (2)
N1—C1—C2	116.67 (16)	C2—C3—H3	120.00
C1—N1—H1	119.4 (15)	C4—C3—H3	120.00
C7—N1—H1	113.4 (15)	C3—C4—H4	121.00
C1—C2—C3	119.57 (16)	C5—C4—H4	121.00
O2—C2—C3	124.73 (17)	C1—C6—H6	121.00
O2—C2—C1	115.70 (16)	C5—C6—H6	121.00
C2—C3—C4	120.61 (17)	N1—C7—H7	118.2 (12)
C3—C4—C5	118.97 (17)	C8—C7—H7	117.5 (12)
Cl1—C5—C4	119.22 (14)	C9—C10—H10	120.00
Cl1—C5—C6	118.73 (13)	C11—C10—H10	120.00
C4—C5—C6	122.05 (17)	C11—C12—H12	121.00
C1—C6—C5	118.93 (16)	C13—C12—H12	120.00
N1—C7—C8	124.28 (17)	C8—C13—H13	119.00
C9—C8—C13	119.22 (16)	C12—C13—H13	119.00
C7—C8—C9	121.97 (16)	O3—C14—H14A	110.00
C7—C8—C13	118.80 (16)	O3—C14—H14B	110.00
O1—C9—C8	120.48 (16)	C15—C14—H14A	110.00
O1—C9—C10	122.15 (16)	C15—C14—H14B	110.00
C8—C9—C10	117.36 (16)	H14A—C14—H14B	108.00
C9—C10—C11	120.87 (17)	C15—C16—H16	120.00
C10—C11—C12	121.61 (17)	C17—C16—H16	120.00
O3—C11—C12	113.29 (16)	C16—C17—H17	120.00
O3—C11—C10	125.09 (17)	C18—C17—H17	120.00
C11—C12—C13	119.03 (18)	C17—C18—H18	120.00
C8—C13—C12	121.89 (18)	C19—C18—H18	120.00
O3—C14—C15	108.26 (17)	C18—C19—H19	120.00
C14—C15—C16	121.1 (2)	C20—C19—H19	120.00
C14—C15—C20	120.6 (2)	C15—C20—H20	119.00
C16—C15—C20	118.32 (19)	C19—C20—H20	119.00
C14—O3—C11—C10	−0.5 (3)	C7—C8—C9—C10	179.38 (17)
C14—O3—C11—C12	178.36 (19)	C13—C8—C9—O1	178.32 (17)
C11—O3—C14—C15	−179.52 (18)	C13—C8—C9—C10	−1.6 (3)
C7—N1—C1—C2	174.54 (17)	C7—C8—C13—C12	179.1 (2)
C7—N1—C1—C6	−6.3 (3)	C9—C8—C13—C12	0.1 (3)
C1—N1—C7—C8	179.41 (17)	O1—C9—C10—C11	−177.95 (19)
N1—C1—C2—O2	−0.6 (2)	C8—C9—C10—C11	2.0 (3)
N1—C1—C2—C3	180.00 (18)	C9—C10—C11—O3	177.97 (19)
C6—C1—C2—O2	−179.83 (16)	C9—C10—C11—C12	−0.8 (3)
C6—C1—C2—C3	0.8 (3)	O3—C11—C12—C13	−179.7 (2)
N1—C1—C6—C5	−179.28 (16)	C10—C11—C12—C13	−0.8 (3)
C2—C1—C6—C5	−0.2 (2)	C11—C12—C13—C8	1.2 (3)
O2—C2—C3—C4	179.61 (19)	O3—C14—C15—C16	124.1 (2)
C1—C2—C3—C4	−1.1 (3)	O3—C14—C15—C20	−58.9 (3)
C2—C3—C4—C5	0.7 (3)	C14—C15—C16—C17	176.5 (2)
C3—C4—C5—Cl1	−179.94 (17)	C20—C15—C16—C17	−0.5 (4)
C3—C4—C5—C6	0.0 (3)	C14—C15—C20—C19	−175.6 (2)
Cl1—C5—C6—C1	179.67 (13)	C16—C15—C20—C19	1.4 (4)
C4—C5—C6—C1	−0.2 (3)	C15—C16—C17—C18	−0.7 (4)
N1—C7—C8—C9	0.5 (3)	C16—C17—C18—C19	1.1 (4)
N1—C7—C8—C13	−178.51 (18)	C17—C18—C19—C20	−0.2 (4)
C7—C8—C9—O1	−0.7 (3)	C18—C19—C20—C15	−1.1 (4)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1	0.86 (2)	1.93 (2)	2.637 (2)	139 (2)
N1—H1···O2	0.86 (2)	2.27 (2)	2.620 (2)	104.5 (18)
O2—H2···O1i	0.80 (3)	1.84 (3)	2.619 (2)	165 (3)
C7—H7···Cl1ii	0.98 (2)	2.84 (2)	3.7971 (18)	164.5 (17)
C14—H14A···Cg3iii	0.97	2.71	3.569 (3)	148