Crystal structure, Hirshfeld surface analysis and DFT studies of (E)-4-methyl-2-{[(4-methyl­phen­yl)imino]­meth­yl}phenol

In the title compound, C₁₅H₁₅NO, the configuration of the C=N bond of the Schiff base is E, and an intra­molecular O—H⋯N hydrogen bond is observed, forming an intra­molecular S(6) ring motif. The phenol ring is inclined by 45.73 (2)° from the plane of the aniline ring. In the crystal, mol­ecules are linked along the b axis by O—H⋯N and C—H⋯O hydrogen bonds, forming polymeric chains. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the packing arrangement are from H⋯H (56.9%) and H⋯C/C⋯H (31.2%) inter­actions. The density functional theory (DFT) optimized structure at the B3LYP/ 6–311 G(d,p) level is compared with the experimentally determined mol­ecular structure, and the HOMO–LUMO energy gap is provided. The crystal studied was refined as an inversion twin.

1. Chemical context

Azomethines (known as Schiff bases), having imine groups (CH=N) and benzyl rings alternately in the main chain and being conjugated, are inter­esting materials for a wide spectrum of applications, in particular as metal-ion complexing agents and in biological systems (Hökelek et al., 2004; Moroz et al., 2012; Kansız & Dege, 2018). Schiff bases are important in various areas of chemistry and biochemistry because of their biological activity (El-masry et al., 2000) and photochromic properties. They also have applications in various fields such as the measurement and control of radiation intensities in imaging systems and optical computers (Elmalı et al., 1999), and electronics, optoelectronics and photonics (Iwan et al., 2007). They are used as anion sensors (Dalapati et al., 2011) and as non-linear optics compounds (Sun et al., 2012). The present work is part of an ongoing structural study of Schiff bases and their utilization in the synthesis of new organic, excited-state proton-transfer compounds, and fluorescent chemosensors (Faizi et al., 2016, 2018; Kumar et al., 2018; Mukherjee et al., 2018). We report herein the crystal structure as well as the Hirshfeld surface analysis of the title Schiff base (E)-4-methyl-2-{[(4-methyl­phen­yl)imino]­meth­yl}phenol, (I). A comparison between the calculated structure [obtained using density functional theory at the B3LYP/6-311 G(d,p) level] and the experimental data is also presented.

2. Structural commentary

The mol­ecular structure of the title compound is illustrated in Fig. 1. An intra­molecular O—H⋯N hydrogen bond is observed, which forms an S(6) ring motif (Table 1 and Fig. 1). This is a relatively common feature in analogous imine–phenol compounds (see Database survey section). The imine group, which displays a C9—C8—N1—C5 torsion angle of −169.8 (3)°, contributes to the general non-planarity of the mol­ecule. The phenol ring (C9–C14) is inclined by 45.73 (2)° to the aniline ring (C2–C7). The configuration of the C8=N1 bond of this Schiff base is E. The C14—O1 bond is 1.335 (5) Å, which is close to reported values of single C—O bonds in phenols and salicyl­idene­amines (Ozeryanskii et al., 2006). The N1—C8 bond is short at 1.273 (4) Å, strongly indicating the existence of a conjugated C=N bond, while the longer C8—C9 bond [1.460 (5) Å] implies a single bond. All these data support the existence of the phenol–imine tautomer for (I) in its crystalline state. These features are similar to those observed in related 4-di­methyl­amino-N-salicylideneanilines (Pizzala et al., 2000). The C—N, C=N and C—C bond lengths are normal and close to the values observed in related structures (Faizi et al., 2017a,b).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1	0.82	1.87	2.591 (4)	146
C4—H4⋯O1^i	0.93	2.60	3.448 (5)	152
Symmetry code: (i) x, y, z-1.

Figure 1 The mol­ecular structure of (I), with the atom-labelling scheme. Displacement ellipsoids are drawn at the 40% probability level. The intra­molecular O—H⋯N hydrogen bond (see Table 1) is shown as a dashed line.

3. Supra­molecular features

In the crystal of (I), mol­ecules are linked by C—H⋯O inter­actions, forming sheets propagating along the b-axis direction (Fig. 2 and Table 1). There are no other significant inter­molecular inter­actions present.

Figure 2 A view along the b axis of the polymeric chain formed via C—H⋯O inter­molecular hydrogen bonds (see Table 1).

4. Hirshfeld surface analysis

In order to visualize the inter­molecular inter­actions in the crystal packing of (I), a Hirshfeld surface (HS) analysis (Hirshfeld, 1977; Spackman & Jayatilaka, 2009) was carried out using Crystal Explorer 17.5 (Turner et al., 2017). In the HS plotted over d_norm (Fig. 3a), white indicates contacts with distances equal to the sum of van der Waals radii, while the red and blue colours indicate distances shorter (in close contact) or longer (distinct contact) than the van der Waals radii, respectively (Venkatesan et al., 2016). The bright-red spots indicate their roles as respective donors and/or acceptors. The shape-index of the HS is a tool to visualize π–π stacking by the presence of adjacent red and blue triangles; if there are no adjacent red and/or blue triangles, then there are no π–π inter­actions. Fig. 3b clearly suggests that there are no π–π inter­actions in (I).

Figure 3 View of the three-dimensional Hirshfeld surfaces of (I) plotted over (a) dnorm and (b) shape-index.

The overall two-dimensional fingerprint plot (McKinnon et al., 2007) is shown in Fig. 4a, and those delineated into H⋯H, H⋯C/C⋯H, H⋯O/O⋯H, H⋯N/N⋯H and C⋯O/O⋯C contacts are illustrated in Fig. 4b–f, respectively. The most important inter­action is H⋯H, contributing to 56.9% to the overall crystal packing (Fig. 4b). The fingerprint plot delin­eated into H⋯C/C⋯H contacts (31.2% contribution to the HS) shows a pair of characteristic wings, Fig. 4c. The scattered points in a pair of spikes are seen in the fingerprint plot for H⋯O/O⋯H contacts (Fig. 4d, 5.8% contribution). H⋯N/N⋯H contacts contribute 2.7% (Fig. 4e). The scattered points form a the pair of spikes in the fingerprint plot delineated into C⋯O/O⋯C contacts (Fig. 4f, 2.4% contribution). The other inter­actions are C⋯C (0.8%) and O⋯N/C⋯N (0.1%). The Hirshfeld surface analysis confirms the importance of H-atom contacts in establishing the packing. The large number of H⋯H and H⋯C/C⋯H inter­actions suggest that van der Waals inter­actions and hydrogen bonding play the main roles in the crystal packing (Hathwar et al., 2015).

Figure 4 (a) Full two-dimensional fingerprint plot of (I), and those delineated into (b) H⋯H, (c) H⋯C/C⋯H, (d) H⋯O/O⋯H, (e) H⋯N/N⋯H and (f) C⋯O/O⋯C inter­actions.

5. DFT calculations

The optimized structure in the gas phase of compound (I) was generated theoretically via density functional theory (DFT) using the standard B3LYP functional and 6–311 G(d,p) basis-set calculations (Becke, 1993) as implemented in GAUSSIAN 09 (Frisch et al., 2009). The theoretical and experimental results are in good agreement (Table 2). The highest-occupied mol­ecular orbital (HOMO), acting as an electron donor, and the lowest-unoccupied mol­ecular orbital (LUMO), acting as an electron acceptor, are very important parameters for quantum chemistry. When the energy gap is small, the mol­ecule is highly polarizable and has high chemical reactivity (Fukui, 1982; Khan et al., 2015). The DFT calculations provide some important information on the reactivity and site selectivity of the mol­ecular framework, E_HOMO and E_LUMO, which clarify the inevitable charge-exchange collaboration inside the studied material. These data, which also include the electronegativity (χ), hardness (η), electrophilicity (ω), softness (σ) and fraction of electrons transferred (ΔN) are recorded in Table 3. The significance of η and σ is for the evaluation of both the reactivity and stability. The electron transition from the HOMO to the LUMO energy level is shown in Fig. 5. The HOMO and LUMO are localized in the plane extending from the whole phenol ring. The energy band gap [ΔE = E_LUMO-E_HOMO] of the mol­ecule is 2.742 eV, the frontier mol­ecular orbital energies E_HOMO and E_LUMO being −1.6411eV and −5.8477 eV, respectively. The dipole moment of (I) is estimated to be 2.61 Debye.

Table 2
Comparison of observed (X-ray data) and calculated (DFT) geometric parameters (Å, °)

Parameter	X-ray	B3LYP/6–311G(d,p)
O1—C14	1.335 (5)	1.335
N1—C8	1.273 (4)	1.273
N1—C5	1.419 (5)	1.419
C1—C2	1.499 (5)	1.499
C11—C15	1.521 (6)	1.521
C8—C9	1.460 (5)	1.460
C8—N1—C5	120.6 (3)	120.6
N1—C8—C9	120.6 (3)	120.6
C5—N1—C8—C9	−169.8 (3)	−169.8

Table 3
Calculated mol­ecular energies for (I)

Mol­ecular Energy (a.u.) (eV)	Compound (I)
Total Energy, TE (eV)	−19333.931
EHOMO (eV)	−1.641
ELUMO (eV)	−5.848
Gap, ΔE (eV)	4.207
Dipole moment, μ (Debye)	2.61
Ionization potential, I (eV)	1.641
Electron affinity, A	5.848
Electronegativity, χ	3.744
Hardness, η	2.103
Electrophilicity index, ω	3.333
Softness, σ	0.238
Fraction of electron transferred, ΔN	0.774

Figure 5 Energy band gap of the title compound (I).

6. Database survey

A search of the Cambridge Structural Database (CSD, version 5.39; Groom et al., 2016) gave six hits for the {[(3-hy­droxy­phen­yl)imino]­meth­yl}phenol moiety. Two compounds that are very similar compound to (I) have been reported in the literature, viz. N-(3-hy­droxy­phen­yl)-5-meth­oxy­salicylaldimine (BALHUS; Popović et al., 2002) in which a meth­oxy group replaces the methyl group and 4-chloro-2-{[(3-hy­droxy­phen­yl)imino]­meth­yl}phenol (ISENIE; Yu et al., 2011) in which the methyl group is replaced by a chloro group. In the cobalt and manganese complexes di­aqua-bis­{2-hy­droxy-4-[(2-hy­droxy­benzyl­idene)amino]­benzoato-O}bis­(methanol)cobalt(II) (SUL­HOX; Zhou et al. 2009) and (2,2′-{ethane-1,2-diylbis[(nitrilo)­methylyl­idene]}diphenolato){2-hy­droxy-4-[(2-hy­drox­y­benzyl­idene)amino]­benzoato}manganese(III) (UQUBEO; Chen et al., 2011), the methyl group of (I) is replaced by an ester and acts as a ligand. A similar compound, 2-hy­droxy-N′-(2-hy­droxy­benzyl­idene)-4-[(2-hy­droxy­benzyl­idene)amino]­benzohydrazide (TAXRUI; Mitra et al., 2017) is substituted at the methyl group of (I). All these compounds have a similar intra­molecular O—H⋯N hydrogen bond present, forming an S(6) ring motif.

7. Synthesis and crystallization

The title compound (I) was obtained following a published method (Hanika et al., 1971; Samant & Mayadeo 1982). Single crystals of compound (I) were obtained by slow evaporation of an ethanol solution after 4 d.

8. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 4. All H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms, with C—H = 0.93–0.96 Å and U_iso(H) = 1.2U_eq or 1.5U_eq(C,O). The crystal studied was refined an a perfect inversion twin.

Table 4
Experimental details

Crystal data
Chemical formula	C15H15NO
Mr	225.28
Crystal system, space group	Monoclinic, Pc
Temperature (K)	296
a, b, c (Å)	13.8433 (10), 7.0774 (6), 6.2142 (5)
β (°)	95.517 (6)
V (Å^3)	606.01 (8)
Z	2
Radiation type	Mo Kα
μ (mm^−1)	0.08
Crystal size (mm)	0.75 × 0.53 × 0.14
Data collection
Diffractometer	Stoe IPDS 2
Absorption correction	Integration (X-RED32; Stoe & Cie, 2002)
Tmin, Tmax	0.944, 0.989
No. of measured, independent and observed [I > 2σ(I)] reflections	9856, 4081, 2430
Rint	0.063
Refinement
R[F^2 > 2σ(F^2)], wR(F^2), S	0.068, 0.199, 1.05
No. of reflections	4081
No. of parameters	154
No. of restraints	2
H-atom treatment	H-atom parameters constrained
Δρmax, Δρmin (e Å^−3)	0.22, −0.18
Absolute structure	Refined as an inversion twin
Absolute structure parameter	0.5
Computer programs: X-AREA and X-RED32 (Stoe & Cie, 2002), SHELXT2018/3 (Sheldrick, 2015a), SHELXL2018/3 (Sheldrick, 2015b), OLEX2 (Dolomanov et al., 2009), Mercury (Macrae et al., 2020), WinGX (Farrugia, 2012), PLATON (Spek, 2020) and publCIF (Westrip, 2010).

Supporting information

Computing details

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002); program(s) used to solve structure: SHELXT2018/3 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018/3 (Sheldrick, 2015b); molecular graphics: OLEX2 (Dolomanov et al., 2009) and Mercury (Macrae et al., 2020); software used to prepare material for publication: WinGX (Farrugia, 2012), PLATON (Spek, 2020), SHELXL2018 (Sheldrick, 2015b) and publCIF (Westrip, 2010).

(E)-4-Methyl-2-{[(4-methylphenyl)imino]methyl}phenol

Crystal data

C15H15NO	F(000) = 240
Mr = 225.28	Dx = 1.235 Mg m^−3
Monoclinic, Pc	Mo Kα radiation, λ = 0.71073 Å
a = 13.8433 (10) Å	Cell parameters from 12502 reflections
b = 7.0774 (6) Å	θ = 2.9–32.2°
c = 6.2142 (5) Å	µ = 0.08 mm^−1
β = 95.517 (6)°	T = 296 K
V = 606.01 (8) Å^3	Prism, yellow
Z = 2	0.75 × 0.53 × 0.14 mm

Data collection

STOE IPDS 2 diffractometer	4081 independent reflections
Radiation source: sealed X-ray tube, 12 x 0.4 mm long-fine focus	2430 reflections with I > 2σ(I)
Plane graphite monochromator	Rint = 0.063
Detector resolution: 6.67 pixels mm^-1	θmax = 31.9°, θmin = 3.0°
rotation method scans	h = −20→20
Absorption correction: integration (X-RED32; Stoe & Cie, 2002)	k = −10→10
Tmin = 0.944, Tmax = 0.989	l = −9→9
9856 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.068	H-atom parameters constrained
wR(F^2) = 0.199	w = 1/[σ^2(Fo^2) + (0.0974P)^2 + 0.0159P] where P = (Fo^2 + 2Fc^2)/3
S = 1.05	(Δ/σ)max < 0.001
4081 reflections	Δρmax = 0.22 e Å^−3
154 parameters	Δρmin = −0.18 e Å^−3
2 restraints	Absolute structure: Refined as an inversion twin
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.5

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	1.5639 (2)	1.6821 (5)	1.9220 (4)	0.0603 (8)
H1	1.515349	1.711085	1.842779	0.090*
C14	1.6429 (3)	1.7148 (5)	1.8202 (5)	0.0440 (8)
N1	1.4649 (2)	1.7758 (4)	1.5628 (5)	0.0469 (8)
C7	1.2034 (3)	1.8103 (6)	1.3960 (8)	0.0518 (10)
H7	1.148245	1.853517	1.454950	0.062*
C5	1.3754 (3)	1.7675 (5)	1.4311 (6)	0.0429 (8)
C10	1.7225 (3)	1.8176 (5)	1.5071 (6)	0.0436 (7)
H10	1.718715	1.864633	1.366824	0.052*
C8	1.5439 (2)	1.8060 (6)	1.4792 (5)	0.0425 (8)
H8	1.542131	1.842677	1.335168	0.051*
C9	1.6373 (3)	1.7836 (5)	1.6074 (6)	0.0424 (8)
C3	1.2783 (3)	1.6698 (6)	1.1093 (7)	0.0511 (9)
H3	1.274388	1.616264	0.972030	0.061*
C6	1.2917 (3)	1.8269 (6)	1.5136 (6)	0.0510 (10)
H6	1.295318	1.878997	1.651540	0.061*
C2	1.1939 (3)	1.7306 (6)	1.1904 (6)	0.0507 (10)
C13	1.7325 (3)	1.6749 (6)	1.9267 (6)	0.0522 (10)
H13	1.737103	1.626082	2.066301	0.063*
C4	1.3679 (3)	1.6860 (5)	1.2251 (6)	0.0475 (8)
H4	1.423221	1.642909	1.166639	0.057*
C12	1.8156 (3)	1.7078 (6)	1.8251 (7)	0.0537 (11)
H12	1.875444	1.679660	1.899117	0.064*
C15	1.9044 (3)	1.8119 (7)	1.5057 (9)	0.0700 (12)
H15A	1.886555	1.863232	1.364448	0.105*
H15B	1.946511	1.898674	1.587855	0.105*
H15C	1.937339	1.693734	1.492355	0.105*
C11	1.8135 (3)	1.7801 (5)	1.6204 (7)	0.0485 (9)
C1	1.0972 (3)	1.7067 (8)	1.0630 (9)	0.0758 (15)
H1A	1.047278	1.756598	1.143908	0.114*
H1B	1.096915	1.773211	0.928331	0.114*
H1C	1.085349	1.574848	1.035150	0.114*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0522 (14)	0.087 (2)	0.0425 (13)	−0.0019 (15)	0.0088 (11)	0.0087 (15)
C14	0.052 (2)	0.0442 (19)	0.0359 (17)	−0.0002 (15)	0.0035 (15)	0.0015 (15)
N1	0.0464 (16)	0.0464 (18)	0.0479 (19)	−0.0010 (14)	0.0045 (13)	0.0029 (14)
C7	0.0372 (18)	0.054 (2)	0.065 (3)	0.0014 (16)	0.0097 (17)	−0.007 (2)
C5	0.0459 (18)	0.0420 (18)	0.0406 (19)	−0.0030 (16)	0.0037 (15)	0.0054 (16)
C10	0.0442 (16)	0.0428 (17)	0.0435 (18)	−0.0017 (15)	0.0030 (14)	0.0031 (15)
C8	0.0434 (18)	0.0474 (19)	0.0359 (17)	−0.0036 (14)	−0.0001 (14)	0.0054 (14)
C9	0.0421 (16)	0.0426 (18)	0.042 (2)	−0.0034 (15)	0.0014 (15)	−0.0044 (16)
C3	0.054 (2)	0.051 (2)	0.048 (2)	−0.0009 (18)	−0.0012 (17)	−0.0079 (18)
C6	0.057 (2)	0.050 (2)	0.048 (2)	0.0011 (18)	0.0102 (18)	0.0016 (18)
C2	0.046 (2)	0.045 (2)	0.060 (2)	0.0003 (16)	0.0012 (18)	0.0048 (18)
C13	0.059 (2)	0.0455 (19)	0.050 (2)	−0.0028 (18)	−0.0029 (19)	−0.0017 (17)
C4	0.0477 (19)	0.0468 (19)	0.050 (2)	0.0037 (15)	0.0117 (15)	0.0010 (16)
C12	0.045 (2)	0.052 (3)	0.061 (3)	0.0010 (15)	−0.0061 (18)	−0.0008 (18)
C15	0.051 (2)	0.078 (3)	0.082 (3)	−0.001 (2)	0.010 (2)	0.007 (3)
C11	0.0428 (18)	0.0413 (18)	0.062 (2)	−0.0055 (14)	0.0066 (17)	−0.0073 (16)
C1	0.046 (2)	0.081 (3)	0.096 (4)	−0.002 (2)	−0.014 (2)	−0.002 (3)

Geometric parameters (Å, º)

O1—C14	1.335 (5)	C3—C2	1.384 (6)
O1—H1	0.8200	C3—H3	0.9300
C14—C13	1.378 (5)	C6—H6	0.9300
C14—C9	1.404 (5)	C2—C1	1.499 (5)
N1—C8	1.273 (4)	C13—C12	1.384 (6)
N1—C5	1.419 (5)	C13—H13	0.9300
C7—C6	1.368 (6)	C4—H4	0.9300
C7—C2	1.391 (6)	C12—C11	1.369 (6)
C7—H7	0.9300	C12—H12	0.9300
C5—C6	1.376 (5)	C15—C11	1.521 (6)
C5—C4	1.399 (6)	C15—H15A	0.9600
C10—C9	1.407 (5)	C15—H15B	0.9600
C10—C11	1.408 (5)	C15—H15C	0.9600
C10—H10	0.9300	C1—H1A	0.9600
C8—C9	1.460 (5)	C1—H1B	0.9600
C8—H8	0.9300	C1—H1C	0.9600
C3—C4	1.378 (5)
C14—O1—H1	109.5	C3—C2—C1	121.0 (4)
O1—C14—C13	118.5 (3)	C7—C2—C1	122.1 (4)
O1—C14—C9	122.2 (3)	C14—C13—C12	119.7 (4)
C13—C14—C9	119.3 (3)	C14—C13—H13	120.2
C8—N1—C5	120.6 (3)	C12—C13—H13	120.2
C6—C7—C2	121.7 (4)	C3—C4—C5	119.7 (4)
C6—C7—H7	119.1	C3—C4—H4	120.1
C2—C7—H7	119.1	C5—C4—H4	120.1
C6—C5—C4	118.4 (4)	C11—C12—C13	122.9 (3)
C6—C5—N1	119.5 (3)	C11—C12—H12	118.6
C4—C5—N1	121.9 (3)	C13—C12—H12	118.6
C9—C10—C11	119.6 (4)	C11—C15—H15A	109.5
C9—C10—H10	120.2	C11—C15—H15B	109.5
C11—C10—H10	120.2	H15A—C15—H15B	109.5
N1—C8—C9	120.6 (3)	C11—C15—H15C	109.5
N1—C8—H8	119.7	H15A—C15—H15C	109.5
C9—C8—H8	119.7	H15B—C15—H15C	109.5
C14—C9—C10	120.2 (3)	C12—C11—C10	118.2 (4)
C14—C9—C8	121.2 (3)	C12—C11—C15	123.1 (3)
C10—C9—C8	118.4 (3)	C10—C11—C15	118.6 (4)
C4—C3—C2	122.2 (4)	C2—C1—H1A	109.5
C4—C3—H3	118.9	C2—C1—H1B	109.5
C2—C3—H3	118.9	H1A—C1—H1B	109.5
C7—C6—C5	121.0 (4)	C2—C1—H1C	109.5
C7—C6—H6	119.5	H1A—C1—H1C	109.5
C5—C6—H6	119.5	H1B—C1—H1C	109.5
C3—C2—C7	116.9 (3)
C8—N1—C5—C6	−148.2 (4)	C4—C3—C2—C7	0.2 (6)
C8—N1—C5—C4	37.2 (6)	C4—C3—C2—C1	−178.4 (4)
C5—N1—C8—C9	−169.8 (3)	C6—C7—C2—C3	−0.5 (6)
O1—C14—C9—C10	179.4 (4)	C6—C7—C2—C1	178.1 (4)
C13—C14—C9—C10	−2.2 (5)	O1—C14—C13—C12	−179.9 (3)
O1—C14—C9—C8	−5.9 (5)	C9—C14—C13—C12	1.7 (6)
C13—C14—C9—C8	172.5 (4)	C2—C3—C4—C5	−0.5 (6)
C11—C10—C9—C14	0.8 (5)	C6—C5—C4—C3	1.0 (6)
C11—C10—C9—C8	−174.0 (3)	N1—C5—C4—C3	175.6 (4)
N1—C8—C9—C14	4.9 (6)	C14—C13—C12—C11	0.2 (6)
N1—C8—C9—C10	179.6 (3)	C13—C12—C11—C10	−1.7 (6)
C2—C7—C6—C5	1.0 (7)	C13—C12—C11—C15	−178.4 (4)
C4—C5—C6—C7	−1.3 (6)	C9—C10—C11—C12	1.1 (5)
N1—C5—C6—C7	−176.0 (4)	C9—C10—C11—C15	178.0 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	0.82	1.87	2.591 (4)	146
C4—H4···O1^i	0.93	2.60	3.448 (5)	152

Symmetry code: (i) x, y, z−1.