Qu­anti­tative analysis of weak non-covalent inter­actions in (Z)-3-(4-chloro­phen­yl)-2-phenyl­acrylo­nitrile: insights from PIXEL and Hirshfeld surface analysis

Udayakumar, M.; Cerón, M.; Ceballos, P.; Percino, J.; Thamotharan, S.

doi:10.1107/S2056989019003694

research communications

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ISSN: 2056-9890

Volume 75| Part 4| April 2019| Pages 499-505

https://doi.org/10.1107/S2056989019003694

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Quantitative analysis of weak non-covalent interactions in (Z)-3-(4-chlorophenyl)-2-phenylacrylonitrile: insights from PIXEL and Hirshfeld surface analysis

Mani Udayakumar,^a Margarita Cerón,^b Paulina Ceballos,^b Judith Percino ^b and Subbiah Thamotharan ^a ^*

^aBiomolecular Crystallography Laboratory, Department of Bioinformatics, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur 613 401, India, and ^bUnidad de Polímeros y Electrónica Orgánica, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Val3-Ecocampus Valsequillo, Independencia O2 Sur 50, San Pedro Zacachimalpa, Puebla, CP 72960, Mexico
^*Correspondence e-mail: thamu@scbt.sastra.edu

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 21 February 2019; accepted 16 March 2019; online 26 March 2019)

In the solid state, the title compound, C₁₅H₁₀ClN, is disordered over two orientations with a refined occupancy ratio of 0.86 (2):0.14 (2). The crystal structure is mainly stabilized by intermolecular C—H⋯N and C—H⋯Cl hydrogen bonds, and C—H⋯π interactions. The molecules pack in columns and adjacent columns are linked by weak C—H⋯Cl interactions. The PIXEL energy analysis suggests that the intermolecular C—H⋯π interactions form a strong dimer in the major component. Hirshfeld analysis reveals that H⋯C, H⋯H, H⋯Cl and H⋯N contacts are the most important contributors to the crystal packing.

Keywords: crystal structure; acrylonitrile; conjugation; hydrogen bonding; C—H⋯π interactions; PIXEL; Hirshfeld surface; two-dimensional fingerprint plots..

CCDC reference: 1903772

1. Chemical context

Acrylonitrile compounds have been used as building blocks in flavonoid pigments (Fringuelli et al., 1994 ) and anticancer agents (Özen et al., 2016 ). Some of these derivatives have been used to produce light-emitting diodes (LEDs) (Maruyama et al., 1998 ; Segura et al., 1999 ). Owing to the versatile physicochemical and biological properties of acrylonitrile derivatives, we have been investigating the optical properties of several (Z)-3-(substituted phenyl)-2-(pyridyl)acrylonitrile compounds with different donor and acceptor moieties (Percino et al., 2010 , 2011 , 2014a ,b , 2016a ,b , 2017 ). Recently, we explored various (Z)-3-(4-halophenyl)-2-(pyridin-2/3/4-yl)acrylonitrile derivatives in order to understand the role of halogen substituents in the context of optical properties and supramolecular associations in the solid state (Venkatesan et al., 2018 ).

In this work, we report the synthesis and the crystal and molecular structures of an acrylonitrile derivative, namely (Z)-3-(4-chlorophenyl)-2-phenylacrylonitrile (I). We also report herein a detailed analysis of the intermolecular interactions for different molecular pairs observed in I using the PIXEL method (Gavezzotti, 2002 , 2011 ). Hirshfeld surface analysis (Spackman & Jayatilaka, 2009 ) was also performed to visualize the short contacts in the crystal of I and to determine the relative contributions of the various non-covalent interactions present in the crystal structure using two-dimensional (2D) fingerprint plots (Spackman & McKinnon, 2002 ; McKinnon et al., 2007 ). We also highlight the importance of the weak halogen bonds observed in the crystal structure.

2. Computational details

Structural optimization was carried out using GAUSSIAN09 (Frisch et al., 2013 ) with the M06-2X/cc-pVTZ level of theory followed by vibrational frequency calculations. The lattice and intermolecular interaction energies were calculated using the CLP-PIXEL program (Version 3.0; Gavezzotti, 2002, 2011). For the intermolecular interaction energy calculations, the crystal structure geometry along with normalized C—H bond lengths to their respective neutron values (Allen, 1986 ) was used and the electron density has been obtained at the MP2/6-31G(d,p) level of theory using GAUSSIAN09.

3. Structural commentary

The molecular structure of compound I is shown in Fig. 1. The whole molecule is disordered over two orientations with a refined occupancy ratio of 0.86 (2):0.14 (2). Only the major component is considered for further analysis and discussion. The bond lengths in I clearly indicate the presence of electron delocalization throughout the molecule. The geometrical features of the molecule were further analyzed using the MOGUL geometry check utility available in Mercury (Macrae et al., 2008 ). The result suggests that the torsion angles C8—C7—C15—N2 [−166.6 (2)°] and C1—C7—C15—N2 [10.5 (2)°] are unusual. The molecule adopts a twisted conformation and the dihedral angle between the planes of the phenyl (C1–C6) and 4-chlorophenyl (C9–C14) rings is 51.91 (8)°. When the unsubstituted phenyl ring in I was replaced by a pyridine ring (Venkatesan et al., 2018), the molecular twist was reduced by at least 50%, and in pyridine containing compounds, the dihedral angles between the two rings are in a range of ca 1–27° (Cambridge Structural Database; Groom et al., 2016 ).

Figure 1
(a) The disordered components of compound I (major shown with solid lines and minor with broken lines) and (b) displacement ellipsoids of the major disordered component of I at the 50% pobability level, with the atom-labelling scheme.

To understand the conformational flexibility of I, we performed a structural optimization using the GAUSSIAN09 program (Frisch et al., 2013), without any constraints. The vibrational frequency calculation confirmed that the optimized structure is found to be the true energy minima on the potential energy surface, since there were no negative frequencies observed for the optimized geometries. The X-ray and optimized structures superimpose well, with an r.m.s. deviation of 0.13 Å (Fig. 2).

Figure 2
Structural overlay of the X-ray (grey) and optimized (green) structures.

4. Supramolecular features

In the crystal, molecules are arranged in a columnar packing mode via intermolecular C—H⋯π, C—H⋯N and C—H⋯Cl interactions (Table 1 and Fig. 3). Adjacent columns are interconnected by halogen bonds (C—H⋯Cl). Within the column, there is nitrile–nitrile stacking and molecules are interlinked by C—H⋯π and C—H⋯N interactions (Table 1).

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of rings C1–C6 and C9–C14 of the major disordered component. Cg1′ and Cg2′ are the centroids of rings C1′–C6′ and C9′–C14′ of the minor disordered component.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C5—H5⋯Cl1′ⁱ	0.95	2.69	3.292 (5)	122
C8—H8⋯N2ⁱⁱ	0.95	2.46	3.361 (6)	157
C8—H8⋯N2′ⁱⁱ	0.95	2.53	3.44 (4)	160
C14—H14⋯N2′	0.95	2.54	3.22 (6)	129
C3—H3⋯Cg1ⁱⁱⁱ	0.95	2.99	3.860 (4)	153
C3—H3⋯Cg2′ⁱⁱⁱ	0.95	2.95	3.784 (9)	148
C11—H11⋯Cg2^iv	0.95	2.96	3.418 (7)	111
C11—H11⋯Cg1′^iv	0.95	2.97	3.486 (15)	115
C14—H14⋯Cg1^v	0.95	2.81	3.503 (3)	130
C14—H14⋯Cg2′^v	0.95	2.84	3.585 (8)	136
C3′—H3′⋯Cg2^iv	0.95	2.59	3.32 (6)	134
C3′—H3′⋯Cg1′^iv	0.95	2.62	3.39 (6)	139
C6′—H6′⋯Cg1^v	0.95	2.85	3.52 (2)	129
C6′—H6′⋯Cg2′^v	0.95	2.93	3.64 (2)	132
Symmetry codes: (i) $[-x+1, y, -z+{\script{1\over 2}}]$ ; (ii) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1]$ ; (iii) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ ; (iv) $[-x+{\script{1\over 2}}, y+{\script{1\over 2}}, z]$ ; (v) -x+1, -y, -z+1.

Figure 3
A view along the b axis of the crystal packing of compound I, showing the nitrile stacking in the purple rectangles.

5. Lattice and intermolecular interaction energies

The lattice energy calculations reveal that the crystal packing is predominantly stabilized through dispersion energy (71%) and the electrostatic (Coulombic + polarization) energy contributes 29% towards the stabilization of the crystal structure. The total lattice energy (−28.9 kcal mol⁻¹) is the sum of the Coulombic (−10.5 kcal mol⁻¹), polarization (−4.7 kcal mol⁻¹), dispersion (−36.6 kcal mol⁻¹) and repulsion (22.9 kcal mol⁻¹) terms. Furthermore, different motifs formed in the major component of I and their energetics are discussed below (Table 2).

Table 2
Intermolecular interaction energies (in kcal mol⁻¹) for different molecular pairs observed in the major component of the title compound; CD is the centroid-to-centroid distance

Motif	CD (Å)	Symmetry	E_Coul	E_pol	E_{energy-dispersive}	E_rep	E_tot	Possible interactions	Geometry (Å, °)^a
M1	5.163	−x + 1, −y, −z + 1	−4.0	−1.4	−12.5	8.3	−9.5	C14—H14⋯Cg1	2.81, 130
M2	4.820	−x + 1, −y + 1, −z + 1	−3.1	−1.5	−11.5	7.4	−8.7	C15⋯C15(π–π)	3.274 (4)
M3	5.122	−x + $[{1\over 2}]$ , y − $[{1\over 2}]$ , z	−1.9	−1.0	−10.0	5.6	−7.3	C3—H3⋯Cg1	2.99, 153
		−x + $[{1\over 2}]$ , y + $[{1\over 2}]$ , z						C11—H11⋯Cg2	2.96, 111
M4	6.925	x − $[{1\over 2}]$ , −y + $[{1\over 2}]$ , −z + 1	−4.3	−1.6	−5.2	5.3	−5.9	C8—H8⋯N2	2.34, 156
								C10—H10⋯N2	2.66, 143
M5	11.134	−x + 1, y, −z + $[{3\over 2}]$	−1.1	−0.5	−3.2	1.8	−2.8	C13—H13⋯Cl1	2.95, 152
M6	13.104	−x + $[{1\over 2}]$ , −y + $[{1\over 2}]$ , z − $[{1\over 2}]$	−0.6	−0.4	−2.8	2.1	−1.6	C4—H4⋯Cl1	2.98, 114
Note: (a) neutron values are given for all D—H⋯A interactions.

Inversion-related molecules form the strongest dimer (motif M1) which is held by intermolecular C—H⋯π interactions with an interaction energy of −9.5 kcal mol⁻¹. As expected, the dispersion contribution (70%) is more significant towards the stabilization of this dimer. Further, this dimer is flanked on both sides by other molecules. As shown in Fig. 4(a), these molecules interact with the central dimer (motif M1) through two C—H⋯π interactions (motif M3; interaction energy = −7.3 kcal mol⁻¹). It is to be noted that the motif M3 is more dispersive in nature (78%) than motif M1. The nitrile group of one molecule stacks with the nitrile group of an inversion-related molecule (motif M2; interaction energy = −8.7 kcal mol⁻¹ and 71% dispersion contribution). The shortest distance observed between two C15 atoms is 3.274 (4) Å and the motif M2 is also flanked on both sides by motif M3. These motifs act together to link the molecules into a chain which runs parallel to the b axis (Fig. 4b).

Figure 4
(a) The molecular chain generated by intermolecular C—H⋯π interactions (motif sequence M3⋯M1⋯M3) and (b) adjacent M3 motifs interlinked by nitrile–nitrile stacking (motif M2). The centroids are shown as small spheres (Cg1 blue and Cg2 red).

Motif M4 (interaction energy = −5.9 kcal mol⁻¹) is stabilized by three-centred intermolecular C—H⋯N interactions in which the nitrile N atom acts as an acceptor and the vinylic proton (H9) and one of the protons (H10) of chlorophenyl ring are involved as donors (Fig. 5). These three-centred interactions link the molecules into a chain which runs parallel to the a axis. 53% of the electrostatic and 47% of the dispersion energy contribute towards stabilization of motif M4.

Figure 5
(a) The molecular chain formed by three-centred C—H⋯N interactions, (b) a closed molecular dimer generated by intermolecular C—H⋯Cl interactions and (c) a C(12) chain formed by intermolecular C—H⋯Cl interactions.

The energetically least-stable dimers (motifs M5 and M6) are formed by intermolecular C—H⋯Cl interactions (Fig. 5). These two interactions help to link adjacent columns in the crystal, as mentioned above. The molecules form an R₂²(8) loop in the case of motif M5, with an interaction energy of −2.8 kcal mol⁻¹. We note that the dispersion energy (67%) contributes nearly double that of the electrostatic energy (33%) for the stabilization of this motif. Further, a molecular chain is related to motif M6 (interaction energy = −1.6 kcal mol⁻¹) propagating along the c axis direction. This dimer is more dispersive in nature and 75% of the dispersion energy contributes towards the stabilization. Motifs M4–M6 combine to form sheets parallel to the ac plane (Fig. 6).

Figure 6
The molecular sheet assembled by intermolecular C—H⋯N and C—H⋯Cl interactions.

6. Hirshfeld surface analysis and 2D fingerprint plots

The Hirshfeld surface analysis (Spackman & Jayatilaka, 2009) and the associated 2D fingerprint plots (McKinnon et al., 2007) were performed with CrystalExplorer17 (Turner et al., 2017 ) for both the major and the minor disordered components. For each component, the occupancies of all atoms were made equal to 1. Hirshfeld surface (HS) analysis was carried out in order to gain more insight into the nature and extent of the intermolecular interactions and to quantify the relative contributions of the different non-covalent interactions that exist in the crystal. The HS surface was mapped over d_norm and the diagram reveals that motifs M2 and M4 are visible as red spots on the HS (Fig. 7) in the major disordered component. It is to be noted that a pale-red spot is noticed for motif M3 when compared to the other two motifs. As mentioned above, motif M4 has two intermolecular C—H⋯N interactions and one of them is found to be a close contact (C8—H8⋯N2).

Figure 7
2D fingerprint plots for different intermolecular contacts and the Hirshfeld surface mapped over d_norm to hightlight the short intermolecular contacts for the major disordered component of I.

2D fingerprint plots for the major and the minor components are illustrated in Figs. 7 and 8. For the major component of I, it is found that the contributions for the H⋯C (33.6%) and H⋯H (28.6%) contacts are relatively high in comparison to other non-covalent interactions (Fig. 7). It is of interest to note that the H⋯Cl contacts also contribute substantially (17.9%) to the crystal packing. As noted above, neighbouring columns are interlinked in the crystal via intermolecular H⋯Cl contacts. The intermolecular H⋯N contacts contribute 10.6% towards the crystal packing. The other contacts, such as C⋯C (4.1%) and C⋯N (3.8%), also supplement the overall crystal packing. The former contact represents the motifs M2 and M3, while the latter contact is mainly due to the stacking of the nitrile groups.

Figure 8
2D fingerprint plots for the different intermolecular contacts and their relative contributions for the minor disordered component of I.

In the case of the minor component, the relative contributions of some of the intermolecular contacts are very similar to those for the major component, as shown in Fig. 8. However, the H⋯Cl contacts are reduced by 4.9%. This difference clearly indicates the importance of halogen interactions in the major component of the title compound.

7. Database survey

A search of the Cambridge Structural Database (CSD, Version 5.40, update of February 2019; Groom et al., 2016) using the (Z)-2,3-diphenylacrylonitrile skeleton yielded 306 hits, which include multiple reports of a number of structures. Limiting the search to structures with a halogen atom attached to the phenyl ring, as in the title compound, yielded 13 hits. Two structures are similar to the title compound, namely 2-(4-aminophenyl)-3-(4-bromophenyl)acrylonitrile (CSD refcode IYIBOJ; Bai et al., 2016 ) and (Z)-3-(2-chloro-6-fluorophenyl)-2-(4-methoxyphenyl)acrylonitrile (KEVQOS; Naveen et al., 2006 ). Here the planes of the aryl rings are inclined to each other by 66.16 (13)° in IYIBOJ and 57.43 (19)° in KEVQOS. In I, this dihedral angle is 51.91 (8)° in the major disordered component and 61.8 (13)° in the minor disordered component.

8. Synthesis and crystallization

A mixture of phenylacetonitrile (0.53 ml, 4.6 mmol) and 4-chlorobenzaldehyde (4.6 mmol, 0.65 g) was stirred at room temperature for 10 min. Subsequently, the temperature was increased gradually to 403 K and maintained at that temperature for 39 h. Initially, the mixture was colourless and then became viscous and dark. This viscous solution was cooled, treated with hexane and finally filtered. The filtrate contained small colourless crystals. Further purification of the title compound (yield 83%, m.p. 368–370 K) was carried out by recrystallization from hexane. Colourless plate-like crystals, suitable for X-ray diffraction analysis, were obtained by slow evaporation of a solution of I in ethanol at 277 K after a period of 7 d.

9. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3. The whole molecule was disordered and the major and minor components of the disorder refined to 0.86 (2) and 0.14 (2), respectively. All H atoms were placed in calculated positions and treated as riding, with C—H = 0.95 Å and U_iso(H) = 1.2U_eq(C).

Table 3
Experimental details

Crystal data
Chemical formula	C₁₅H₁₀ClN
M_r	239.69
Crystal system, space group	Orthorhombic, Pbcn
Temperature (K)	100
a, b, c (Å)	13.3417 (8), 7.1030 (5), 25.1418 (18)
V (Å³)	2382.6 (3)
Z	8
Radiation type	Cu Kα
μ (mm⁻¹)	2.61
Crystal size (mm)	0.31 × 0.29 × 0.05

Data collection
Diffractometer	SuperNova, Dual, Cu at zero, Atlas
Absorption correction	Analytical (CrysAlis PRO; Agilent, 2012 )
T_min, T_max	0.560, 0.889
No. of measured, independent and observed [I > 2σ(I)] reflections	6681, 2132, 1930
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.598

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.050, 0.122, 1.10
No. of reflections	2132
No. of parameters	212
No. of restraints	44
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.28, −0.20
Computer programs: CrysAlis PRO (Agilent, 2012), SHELXS2013 (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), PLATON (Spek, 2009 ), Mercury (Macrae et al., 2008) and publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 1903772

Crystal structure: contains datablocks I, Global. DOI: https://doi.org/10.1107/S2056989019003694/su5483sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989019003694/su5483Isup2.hkl

checkCIF report

Computing details top

Data collection: (CrysAlis PRO; Agilent, 2012); cell refinement: (CrysAlis PRO; Agilent, 2012); data reduction: (CrysAlis PRO; Agilent, 2012); program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014/7 (Sheldrick, 2015); molecular graphics: PLATON (Spek, 2009) and Mercury (Macrae et al., 2008); software used to prepare material for publication: publCIF (Westrip, 2010).

(Z)-3-(4-Chlorophenyl)-2-phenylacrylonitrile top

Crystal data top

C₁₅H₁₀ClN	D_x = 1.336 Mg m⁻³
M_r = 239.69	Cu Kα radiation, λ = 1.54178 Å
Orthorhombic, Pbcn	Cell parameters from 3085 reflections
a = 13.3417 (8) Å	θ = 4.8–67.4°
b = 7.1030 (5) Å	µ = 2.61 mm⁻¹
c = 25.1418 (18) Å	T = 100 K
V = 2382.6 (3) Å³	Plate, colourless
Z = 8	0.31 × 0.29 × 0.05 mm
F(000) = 992

Data collection top

SuperNova, Dual, Cu at zero, Atlas diffractometer	1930 reflections with I > 2σ(I)
Radiation source: SuperNova (Cu) X-ray Source	R_int = 0.031
ω scans	θ_max = 67.3°, θ_min = 3.5°
Absorption correction: analytical (CrysAlisPro; Agilent, 2012)	h = −15→11
T_min = 0.560, T_max = 0.889	k = −6→8
6681 measured reflections	l = −23→30
2132 independent reflections

Refinement top

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)] = 0.050	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.122	H-atom parameters constrained
S = 1.10	w = 1/[σ²(F_o²) + (0.0441P)² + 2.5669P] where P = (F_o² + 2F_c²)/3
2132 reflections	(Δ/σ)_max = 0.001
212 parameters	Δρ_max = 0.28 e Å⁻³
44 restraints	Δρ_min = −0.20 e Å⁻³

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	0.34667 (5)	0.49268 (11)	0.74493 (3)	0.0369 (2)	0.8598 (17)
C12	0.3468 (2)	0.4040 (5)	0.68021 (11)	0.0258 (7)	0.8598 (17)
C11	0.2585 (4)	0.4067 (10)	0.65042 (19)	0.0251 (12)	0.8598 (17)
H11	0.1975	0.4506	0.6654	0.030*	0.8598 (17)
C10	0.26234 (19)	0.3441 (7)	0.59886 (15)	0.0230 (8)	0.8598 (17)
H10	0.2031	0.3475	0.5779	0.028*	0.8598 (17)
C9	0.35071 (18)	0.2756 (4)	0.57609 (11)	0.0211 (6)	0.8598 (17)
C14	0.43690 (19)	0.2651 (4)	0.60818 (12)	0.0238 (6)	0.8598 (17)
H14	0.4969	0.2135	0.5940	0.029*	0.8598 (17)
C13	0.4351 (2)	0.3289 (4)	0.66008 (13)	0.0251 (6)	0.8598 (17)
H13	0.4935	0.3215	0.6817	0.030*	0.8598 (17)
C8	0.34672 (17)	0.2150 (4)	0.52053 (11)	0.0221 (6)	0.8598 (17)
H8	0.2831	0.1722	0.5086	0.026*	0.8598 (17)
C7	0.41994 (17)	0.2112 (3)	0.48387 (10)	0.0209 (5)	0.8598 (17)
C15	0.52002 (18)	0.2729 (4)	0.49672 (11)	0.0223 (6)	0.8598 (17)
C1	0.4052 (2)	0.1547 (4)	0.42761 (11)	0.0221 (6)	0.8598 (17)
C2	0.3269 (2)	0.0340 (5)	0.41280 (15)	0.0243 (7)	0.8598 (17)
H2	0.2827	−0.0136	0.4392	0.029*	0.8598 (17)
C3	0.3133 (3)	−0.0165 (6)	0.36020 (18)	0.0295 (7)	0.8598 (17)
H3	0.2595	−0.0976	0.3508	0.035*	0.8598 (17)
C4	0.3776 (2)	0.0501 (5)	0.32082 (12)	0.0316 (8)	0.8598 (17)
H4	0.3685	0.0140	0.2848	0.038*	0.8598 (17)
C5	0.4552 (2)	0.1704 (5)	0.33516 (12)	0.0319 (7)	0.8598 (17)
H5	0.4989	0.2181	0.3086	0.038*	0.8598 (17)
C6	0.46955 (19)	0.2214 (4)	0.38776 (13)	0.0258 (6)	0.8598 (17)
H6	0.5235	0.3024	0.3969	0.031*	0.8598 (17)
N2	0.6003 (4)	0.322 (2)	0.5051 (3)	0.0275 (13)	0.8598 (17)
Cl1'	0.4211 (3)	−0.0021 (6)	0.26712 (16)	0.0355 (12)	0.1402 (17)
C12'	0.3955 (15)	0.065 (3)	0.3320 (6)	0.0258 (7)	0.1402 (17)
C11'	0.3213 (17)	−0.031 (3)	0.3605 (10)	0.0251 (12)	0.1402 (17)
H11'	0.2808	−0.1233	0.3438	0.030*	0.1402 (17)
C10'	0.3084 (15)	0.012 (3)	0.4131 (9)	0.0230 (8)	0.1402 (17)
H10'	0.2584	−0.0516	0.4330	0.028*	0.1402 (17)
C9'	0.3673 (11)	0.148 (2)	0.4380 (6)	0.0211 (6)	0.1402 (17)
C14'	0.4402 (11)	0.240 (2)	0.4083 (7)	0.0238 (6)	0.1402 (17)
H14'	0.4806	0.3321	0.4253	0.029*	0.1402 (17)
C13'	0.4562 (13)	0.202 (2)	0.3551 (8)	0.0251 (6)	0.1402 (17)
H13'	0.5062	0.2656	0.3352	0.030*	0.1402 (17)
C8'	0.3491 (12)	0.192 (2)	0.4942 (5)	0.0221 (6)	0.1402 (17)
H8'	0.2817	0.1744	0.5054	0.026*	0.1402 (17)
C7'	0.4111 (9)	0.251 (2)	0.5321 (5)	0.0209 (5)	0.1402 (17)
C15'	0.5165 (10)	0.281 (3)	0.5210 (7)	0.0223 (6)	0.1402 (17)
C1'	0.3810 (13)	0.294 (3)	0.5875 (6)	0.0221 (6)	0.1402 (17)
C2'	0.2837 (15)	0.357 (5)	0.6003 (10)	0.0243 (7)	0.1402 (17)
H2'	0.2315	0.3515	0.5746	0.029*	0.1402 (17)
C3'	0.265 (3)	0.429 (9)	0.6513 (12)	0.0295 (7)	0.1402 (17)
H3'	0.2066	0.5025	0.6568	0.035*	0.1402 (17)
C4'	0.3293 (16)	0.396 (4)	0.6948 (8)	0.0316 (8)	0.1402 (17)
H4'	0.3103	0.4223	0.7305	0.038*	0.1402 (17)
C5'	0.4215 (14)	0.322 (3)	0.6819 (7)	0.0319 (7)	0.1402 (17)
H5'	0.4684	0.2946	0.7093	0.038*	0.1402 (17)
C6'	0.4461 (14)	0.288 (3)	0.6300 (8)	0.0258 (6)	0.1402 (17)
H6'	0.5140	0.2566	0.6225	0.031*	0.1402 (17)
N2'	0.598 (3)	0.323 (14)	0.514 (3)	0.0275 (13)	0.1402 (17)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0262 (4)	0.0535 (5)	0.0309 (4)	0.0039 (3)	0.0002 (2)	−0.0111 (3)
C12	0.0270 (15)	0.0252 (14)	0.0252 (16)	0.0003 (12)	0.0022 (11)	−0.0039 (13)
C11	0.0152 (15)	0.023 (3)	0.0373 (14)	0.0016 (17)	0.0025 (11)	0.0000 (13)
C10	0.0133 (15)	0.0221 (16)	0.0336 (13)	−0.0006 (15)	−0.0016 (13)	0.0021 (11)
C9	0.0133 (13)	0.0151 (12)	0.0348 (14)	−0.0033 (11)	−0.0009 (10)	0.0039 (11)
C14	0.0145 (13)	0.0231 (14)	0.0339 (15)	0.0026 (10)	0.0024 (13)	0.0000 (13)
C13	0.0168 (12)	0.0252 (14)	0.0335 (16)	−0.0012 (10)	−0.0025 (12)	0.0013 (14)
C8	0.0137 (11)	0.0163 (12)	0.0362 (15)	0.0001 (9)	−0.0004 (12)	0.0033 (12)
C7	0.0130 (11)	0.0159 (11)	0.0336 (12)	0.0010 (9)	−0.0010 (9)	0.0034 (10)
C15	0.0178 (12)	0.0200 (12)	0.0290 (14)	0.0022 (9)	0.0022 (11)	0.0019 (13)
C1	0.0134 (12)	0.0197 (13)	0.0332 (14)	0.0021 (12)	−0.0008 (10)	0.0021 (11)
C2	0.0190 (17)	0.0195 (15)	0.0344 (14)	−0.0013 (12)	0.0006 (13)	0.0025 (11)
C3	0.0250 (16)	0.0279 (17)	0.0355 (15)	−0.0025 (13)	−0.0046 (12)	0.0017 (12)
C4	0.0303 (17)	0.0355 (17)	0.0289 (16)	0.0033 (13)	−0.0026 (12)	0.0013 (13)
C5	0.0269 (14)	0.0346 (17)	0.0343 (16)	0.0020 (13)	0.0021 (13)	0.0059 (13)
C6	0.0173 (13)	0.0228 (14)	0.0372 (17)	−0.0004 (11)	0.0009 (11)	0.0051 (12)
N2	0.0163 (10)	0.0277 (10)	0.039 (4)	0.0005 (8)	0.0000 (12)	0.000 (3)
Cl1'	0.042 (2)	0.036 (2)	0.029 (2)	0.0029 (19)	0.0032 (17)	−0.0018 (17)
C12'	0.0270 (15)	0.0252 (14)	0.0252 (16)	0.0003 (12)	0.0022 (11)	−0.0039 (13)
C11'	0.0152 (15)	0.023 (3)	0.0373 (14)	0.0016 (17)	0.0025 (11)	0.0000 (13)
C10'	0.0133 (15)	0.0221 (16)	0.0336 (13)	−0.0006 (15)	−0.0016 (13)	0.0021 (11)
C9'	0.0133 (13)	0.0151 (12)	0.0348 (14)	−0.0033 (11)	−0.0009 (10)	0.0039 (11)
C14'	0.0145 (13)	0.0231 (14)	0.0339 (15)	0.0026 (10)	0.0024 (13)	0.0000 (13)
C13'	0.0168 (12)	0.0252 (14)	0.0335 (16)	−0.0012 (10)	−0.0025 (12)	0.0013 (14)
C8'	0.0137 (11)	0.0163 (12)	0.0362 (15)	0.0001 (9)	−0.0004 (12)	0.0033 (12)
C7'	0.0130 (11)	0.0159 (11)	0.0336 (12)	0.0010 (9)	−0.0010 (9)	0.0034 (10)
C15'	0.0178 (12)	0.0200 (12)	0.0290 (14)	0.0022 (9)	0.0022 (11)	0.0019 (13)
C1'	0.0134 (12)	0.0197 (13)	0.0332 (14)	0.0021 (12)	−0.0008 (10)	0.0021 (11)
C2'	0.0190 (17)	0.0195 (15)	0.0344 (14)	−0.0013 (12)	0.0006 (13)	0.0025 (11)
C3'	0.0250 (16)	0.0279 (17)	0.0355 (15)	−0.0025 (13)	−0.0046 (12)	0.0017 (12)
C4'	0.0303 (17)	0.0355 (17)	0.0289 (16)	0.0033 (13)	−0.0026 (12)	0.0013 (13)
C5'	0.0269 (14)	0.0346 (17)	0.0343 (16)	0.0020 (13)	0.0021 (13)	0.0059 (13)
C6'	0.0173 (13)	0.0228 (14)	0.0372 (17)	−0.0004 (11)	0.0009 (11)	0.0051 (12)
N2'	0.0163 (10)	0.0277 (10)	0.039 (4)	0.0005 (8)	0.0000 (12)	0.000 (3)

Geometric parameters (Å, º) top

Cl1—C12	1.745 (3)	Cl1'—Cl1'ⁱ	2.275 (9)
C12—C13	1.389 (4)	C12'—C13'	1.389 (17)
C12—C11	1.397 (5)	C12'—C11'	1.399 (18)
C11—C10	1.371 (4)	C11'—C10'	1.368 (19)
C11—H11	0.9500	C11'—H11'	0.9500
C10—C9	1.398 (4)	C10'—C9'	1.391 (17)
C10—H10	0.9500	C10'—H10'	0.9500
C9—C14	1.407 (4)	C9'—C14'	1.388 (15)
C9—C8	1.462 (4)	C9'—C8'	1.467 (15)
C14—C13	1.382 (4)	C14'—C13'	1.383 (16)
C14—H14	0.9500	C14'—H14'	0.9500
C13—H13	0.9500	C13'—H13'	0.9500
C8—C7	1.344 (3)	C8'—C7'	1.331 (14)
C8—H8	0.9500	C8'—H8'	0.9500
C7—C15	1.442 (3)	C7'—C15'	1.448 (14)
C7—C1	1.483 (4)	C7'—C1'	1.483 (15)
C15—N2	1.146 (5)	C15'—N2'	1.148 (17)
C1—C6	1.402 (4)	C1'—C6'	1.377 (16)
C1—C2	1.402 (4)	C1'—C2'	1.410 (18)
C2—C3	1.382 (5)	C2'—C3'	1.40 (2)
C2—H2	0.9500	C2'—H2'	0.9500
C3—C4	1.393 (5)	C3'—C4'	1.41 (2)
C3—H3	0.9500	C3'—H3'	0.9500
C4—C5	1.390 (4)	C4'—C5'	1.376 (17)
C4—H4	0.9500	C4'—H4'	0.9500
C5—C6	1.384 (4)	C5'—C6'	1.369 (16)
C5—H5	0.9500	C5'—H5'	0.9500
C6—H6	0.9500	C6'—H6'	0.9500
Cl1'—C12'	1.735 (15)

C13—C12—C11	121.7 (3)	C13'—C12'—C11'	122.6 (16)
C13—C12—Cl1	118.7 (2)	C13'—C12'—Cl1'	118.0 (14)
C11—C12—Cl1	119.6 (3)	C11'—C12'—Cl1'	119.1 (15)
C10—C11—C12	118.1 (4)	C10'—C11'—C12'	118 (2)
C10—C11—H11	120.9	C10'—C11'—H11'	120.8
C12—C11—H11	120.9	C12'—C11'—H11'	120.8
C11—C10—C9	122.1 (3)	C11'—C10'—C9'	121.2 (19)
C11—C10—H10	119.0	C11'—C10'—H10'	119.4
C9—C10—H10	119.0	C9'—C10'—H10'	119.4
C10—C9—C14	118.2 (3)	C14'—C9'—C10'	118.6 (14)
C10—C9—C8	117.6 (2)	C14'—C9'—C8'	122.3 (14)
C14—C9—C8	124.2 (2)	C10'—C9'—C8'	119.1 (15)
C13—C14—C9	120.7 (2)	C13'—C14'—C9'	122.5 (15)
C13—C14—H14	119.6	C13'—C14'—H14'	118.8
C9—C14—H14	119.6	C9'—C14'—H14'	118.8
C14—C13—C12	119.0 (2)	C14'—C13'—C12'	116.7 (15)
C14—C13—H13	120.5	C14'—C13'—H13'	121.6
C12—C13—H13	120.5	C12'—C13'—H13'	121.6
C7—C8—C9	129.4 (2)	C7'—C8'—C9'	130.8 (14)
C7—C8—H8	115.3	C7'—C8'—H8'	114.6
C9—C8—H8	115.3	C9'—C8'—H8'	114.6
C8—C7—C15	120.9 (2)	C8'—C7'—C15'	120.8 (13)
C8—C7—C1	124.3 (2)	C8'—C7'—C1'	124.7 (12)
C15—C7—C1	114.7 (2)	C15'—C7'—C1'	114.4 (13)
N2—C15—C7	177.6 (5)	N2'—C15'—C7'	173 (5)
C6—C1—C2	118.2 (3)	C6'—C1'—C2'	114.6 (15)
C6—C1—C7	120.6 (3)	C6'—C1'—C7'	123.4 (15)
C2—C1—C7	121.1 (3)	C2'—C1'—C7'	121.9 (16)
C3—C2—C1	120.7 (3)	C3'—C2'—C1'	119 (2)
C3—C2—H2	119.7	C3'—C2'—H2'	120.4
C1—C2—H2	119.7	C1'—C2'—H2'	120.4
C2—C3—C4	120.8 (4)	C2'—C3'—C4'	123 (2)
C2—C3—H3	119.6	C2'—C3'—H3'	118.6
C4—C3—H3	119.6	C4'—C3'—H3'	118.6
C5—C4—C3	118.9 (3)	C5'—C4'—C3'	115.1 (18)
C5—C4—H4	120.6	C5'—C4'—H4'	122.5
C3—C4—H4	120.6	C3'—C4'—H4'	122.5
C6—C5—C4	120.8 (3)	C6'—C5'—C4'	120.5 (17)
C6—C5—H5	119.6	C6'—C5'—H5'	119.8
C4—C5—H5	119.6	C4'—C5'—H5'	119.8
C5—C6—C1	120.6 (3)	C5'—C6'—C1'	125.6 (17)
C5—C6—H6	119.7	C5'—C6'—H6'	117.2
C1—C6—H6	119.7	C1'—C6'—H6'	117.2
C12'—Cl1'—Cl1'ⁱ	122.6 (7)

C13—C12—C11—C10	−4.3 (8)	Cl1'ⁱ—Cl1'—C12'—C11'	−142.8 (8)
Cl1—C12—C11—C10	177.0 (4)	C13'—C12'—C11'—C10'	−0.02 (15)
C12—C11—C10—C9	1.2 (9)	Cl1'—C12'—C11'—C10'	174.0 (14)
C11—C10—C9—C14	2.3 (7)	C12'—C11'—C10'—C9'	0.02 (15)
C11—C10—C9—C8	−179.1 (5)	C11'—C10'—C9'—C14'	−0.1 (3)
C10—C9—C14—C13	−2.9 (4)	C11'—C10'—C9'—C8'	178.7 (14)
C8—C9—C14—C13	178.7 (3)	C10'—C9'—C14'—C13'	0.1 (5)
C9—C14—C13—C12	−0.1 (4)	C8'—C9'—C14'—C13'	−178.6 (15)
C11—C12—C13—C14	3.8 (6)	C9'—C14'—C13'—C12'	−0.1 (4)
Cl1—C12—C13—C14	−177.5 (2)	C11'—C12'—C13'—C14'	0.1 (3)
C10—C9—C8—C7	152.5 (3)	Cl1'—C12'—C13'—C14'	−174.0 (14)
C14—C9—C8—C7	−29.0 (5)	C14'—C9'—C8'—C7'	−31 (3)
C9—C8—C7—C15	−0.2 (4)	C10'—C9'—C8'—C7'	150.5 (17)
C9—C8—C7—C1	−176.9 (2)	C9'—C8'—C7'—C15'	−1 (3)
C8—C7—C1—C6	154.5 (3)	C9'—C8'—C7'—C1'	178.5 (17)
C15—C7—C1—C6	−22.4 (3)	C8'—C7'—C1'—C6'	155 (2)
C8—C7—C1—C2	−25.4 (4)	C15'—C7'—C1'—C6'	−25 (3)
C15—C7—C1—C2	157.7 (3)	C8'—C7'—C1'—C2'	−29 (3)
C6—C1—C2—C3	−0.5 (4)	C15'—C7'—C1'—C2'	151 (2)
C7—C1—C2—C3	179.5 (3)	C6'—C1'—C2'—C3'	8 (5)
C1—C2—C3—C4	0.5 (4)	C7'—C1'—C2'—C3'	−168 (4)
C2—C3—C4—C5	−0.7 (4)	C1'—C2'—C3'—C4'	−18 (8)
C3—C4—C5—C6	0.9 (4)	C2'—C3'—C4'—C5'	13 (7)
C4—C5—C6—C1	−0.9 (4)	C3'—C4'—C5'—C6'	1 (5)
C2—C1—C6—C5	0.6 (4)	C4'—C5'—C6'—C1'	−10 (4)
C7—C1—C6—C5	−179.3 (2)	C2'—C1'—C6'—C5'	5 (4)
Cl1'ⁱ—Cl1'—C12'—C13'	31.4 (14)	C7'—C1'—C6'—C5'	−178 (2)

Symmetry code: (i) −x+1, y, −z+1/2.

Hydrogen-bond geometry (Å, º) top

Cg1 and Cg2 are the centroids of rings C1–C6 and C9–C14 of the major disordered component. Cg1' and Cg2' are the centroids of rings C1'–C6' and C9'–C14' of the minor disordered component.

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5···Cl1′ⁱ	0.95	2.69	3.292 (5)	122
C8—H8···N2ⁱⁱ	0.95	2.46	3.361 (6)	157
C8—H8···N2′ⁱⁱ	0.95	2.53	3.44 (4)	160
C14—H14···N2′	0.95	2.54	3.22 (6)	129
C3—H3···Cg1ⁱⁱⁱ	0.95	2.99	3.860 (4)	153
C3—H3···Cg2′ⁱⁱⁱ	0.95	2.95	3.784 (9)	148
C11—H11···Cg2^iv	0.95	2.96	3.418 (7)	111
C11—H11···Cg1′^iv	0.95	2.97	3.486 (15)	115
C14—H14···Cg1^v	0.95	2.81	3.503 (3)	130
C14—H14···Cg2′^v	0.95	2.84	3.585 (8)	136
C3′—H3′···Cg2^iv	0.95	2.59	3.32 (6)	134
C3′—H3′···Cg1′^iv	0.95	2.62	3.39 (6)	139
C6′—H6′···Cg1^v	0.95	2.85	3.52 (2)	129
C6′—H6′···Cg2′^v	0.95	2.93	3.64 (2)	132

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

Intermolecular interaction energies (in kcal mol^-1) for different molecular pairs observed in the major component of the title compound and CD is the centroid-to-centroid distance. top

Motif	CD (Å)	Symmetry	E_Coul	E_pol	E_disp	E_rep	E_tot	Possible interactions	Geometry (Å, °)^a
M1	5.163	-x+1, -y, -z+1	-4.0	-1.4	-12.5	8.3	-9.5	C14—H14···Cg1	2.81, 130
M2	4.820	-x+1, -y+1, -z+1	-3.1	-1.5	-11.5	7.4	-8.7	C15···C15(π–π)	3.274 (4)
M3	5.122	-x+1/2, y-1/2, z	-1.9	-1.0	-10.0	5.6	-7.3	C3—H3···Cg1	2.99, 153
								C11—H11···Cg2	2.96, 111
M4	6.925	x-1/2, -y+1/2, -z+1	-4.3	-1.6	-5.2	5.3	-5.9	C8—H8···N2	2.34, 156
								C10—H10···N2	2.66, 143
M5	11.134	-x+1, y, -z+3/2	-1.1	-0.5	-3.2	1.8	-2.8	C13—H13···Cl1	2.95, 152
M6	13.104	-x+1/2, -y+1/2, z-1/2	-0.6	-0.4	-2.8	2.1	-1.6	C4—H4···Cl1	2.98, 114

Note: (a) neutron values are given for all D—H···A interactions.

Acknowledgements

The authors would like to thank Laboratorio Nacional de Supercoìmputo del Sureste (LNS–BUAP) for the calculus service and the PEZM NAT17-G (VIEP–BUAP) and SA/103.5/15/12684 (PRODEP–SEP) projects, as well as Dr Maxime A. Siegler (Johns Hopkins University) for assistance with the data collection. ST thanks the DST–SERB for financial support.

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