2-[(4-Chloro­phen­yl)selan­yl]-3,4-di­hydro-2H-benzo[h]chromene-5,6-dione: crystal structure and Hirshfeld analysis

Zukerman-Schpector, J.; Prado, K.E.; Name, L.L.; Cella, R.; Jotani, M.M.; Tiekink, E.R.T.

doi:10.1107/S2056989017007605

research communications

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ISSN: 2056-9890

Volume 73| Part 6| June 2017| Pages 918-924

https://doi.org/10.1107/S2056989017007605

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2-[(4-Chlorophenyl)selanyl]-3,4-dihydro-2H-benzo[h]chromene-5,6-dione: crystal structure and Hirshfeld analysis

Julio Zukerman-Schpector,^a ^* Karinne E. Prado,^b Luccas L. Name,^b Rodrigo Cella,^b Mukesh M. Jotani ^c and Edward R. T. Tiekink ^d

^aDepartmento de Química, Universidade Federal de São Carlos, 13565-905 São Carlos, SP, Brazil, ^bDepartamento de Engenharia Química, Centro Universitário da FEI, 09850-901, São Bernardo do Campo, São Paulo, Brazil, ^cDepartment of Physics, Bhavan's Sheth R. A. College of Science, Ahmedabad, Gujarat 380 001, India, and ^dCentre for Crystalline Materials, School of Science and Technology, Sunway University, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia
^*Correspondence e-mail: julio@power.ufscar.br

Edited by M. Weil, Vienna University of Technology, Austria (Received 12 May 2017; accepted 22 May 2017; online 31 May 2017)

The title organoselenium compound, C₁₉H₁₃ClO₃Se {systematic name: 2-[(4-chlorophenyl)selanyl]-2H,3H,4H,5H,6H-naphtho[1,2-b]pyran-5,6-dione}, has the substituted 2-pyranyl ring in a half-chair conformation with the methylene-C atom bound to the methine-C atom being the flap atom. The dihedral angle between the two aromatic regions of the molecule is 9.96 (9)° and indicates a step-like conformation. An intramolecular Se⋯O interaction of 2.8122 (13) Å is noted. In the crystal, π–π contacts between naphthyl rings [inter-centroid distance = 3.7213 (12) Å] and between naphthyl and chlorobenzene rings [inter-centroid distance = 3.7715 (13) Å], along with C—Cl⋯π(chlorobenzene) contacts, lead to supramolecular layers parallel to the ab plane, which are connected into a three-dimensional architecture via methylene-C—H⋯O(carbonyl) interactions. The contributions of these and other weak contacts to the Hirshfeld surface is described.

Keywords: crystal structure; selenium; pyran derivative; C—Cl⋯π interactions; Hirshfeld surface analysis.

CCDC reference: 1551641

1. Chemical context

The natural product, β-lapachone (see Scheme) can be isolated from the bark of the lapacho tree found in Central and South American countries (see: https://www.beta-lapachone.com/). It exhibits biological activities in the context of cancer (Park et al. 2014 ), being known to induce apoptotic cell-death pathways in a number of cancer cell lines, including breast cancer (Schaffner-Sabba et al., 1984 ), leukaemia (Chau et al., 1998 ) and prostate cancer (Li et al., 1995 ). In an allied application, β-lapachone can be used as a sensitizer in radiotherapy on prostrate (Suzuki et al., 2006 ) and colon (Kim et al., 2005 ) cancer cells.

Compounds of the bio-essential element selenium, found in amino acids such as selenocysteine and selenomethionine, are known to hold potential as pharmaceutical agents (Tiekink, 2012 ), including in the realm of anti-cancer drugs (Seng & Tiekink, 2012 ). A key aspect of developing metal-based drugs is to incorporate a heavy element into the structure of a biologically active organic molecule and with this in mind, it was thought of interest to attempt to incorporate selenium into the structure of β-lapachone. This was attempted by reacting lawsone, paraformaldehyde and (4-chlorophenyl)(ethenyl)selane, as detailed in Synthesis and crystallization. Two major products were isolated, i.e. derivatives of α-lapachone and β-lapachone. The latter, hereafter (I), could be crystallized and was subjected to an X-ray structure determination along with an analysis of its Hirshfeld surface in order to obtain more information on the molecular packing. The results of this study are reported herein.

2. Structural commentary

The substituted 2-pyranyl ring in (I) (Fig. 1) adopts a half-chair conformation with the C13 atom lying 0.620 (3) Å above the plane through the remaining five atoms (r.m.s. deviation = 0.0510 Å). The 12 atoms comprising the naphthalene-1,2-dione ring system are almost coplanar, with an r.m.s. deviation of 0.0152 Å. This plane forms a dihedral angle of 9.96 (9)° with the chlorobenzene ring bound to the selanyl atom, indicating a near parallel disposition and a step-like arrangement between the aromatic substituents about the 2-pyranyl ring. An intramolecular Se⋯O interaction of 2.8122 (13) Å is noted; this observation is discussed further in the Database survey.

Figure 1
The molecular structure of (I)

, showing the atom-labelling scheme and displacement ellipsoids at the 50% probability level.

3. Supramolecular features

In the molecular packing of (I), both rings of the naphthyl residues of centrosymmetrically related molecules form close π–π contacts, i.e. Cg(C2–C4/C9–C11)⋯Cg(C3–C8)ⁱ = 3.7213 (12) Å for an angle of inclination = 0.72 (9)° and symmetry operation (i) −x, −y, −z. Two types of interactions connect centrosymmetric aggregates into a supramolecular layer parallel to the ab plane (Fig. 2a). Thus, π–π interactions between naphthyl and chlorobenzene rings are formed, [Cg(C3–C8)⋯Cg(C14–C19)ⁱⁱ = 3.7715 (13) Å with an angle of inclination = 9.95 (10)° and symmetry operation (ii) −1 + x, y, z] along with C—Cl⋯π(chlorobenzene) contacts between centrosymmetrically related rings (Table 1). Connections between layers are of the type methylene-C—H⋯O(carbonyl) (Table 1) to consolidate the three-dimensional packing (Fig. 2b).

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C14–C19 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C13—H6⋯O3ⁱ	0.97	2.59	3.239 (2)	125
C17—Cl1⋯Cg1ⁱⁱ	1.74 (1)	3.72 (1)	4.000 (2)	86 (1)
Symmetry codes: (i) $[-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) -x+1, -y+1, -z.

Figure 2
The molecular packing in (I)

, showing (a) a view of the supramolecular layer sustained by π–π and C—Cl⋯π interactions and (b) a view of the unit-cell contents in projection down the a axis. The π–π, C—Cl⋯π and C—H⋯O interactions are shown as purple, blue and orange dashed lines, respectively.

4. Hirshfeld surface analysis

The Hirshfeld surfaces calculated on the structure of (I) also provide insight into the intermolecular interactions; the calculation was performed as in a recent publication (Jotani et al., 2016 ). The presence of bright-red spots appearing near the naphthyl-C7 and phenyl-C18 atoms on the Hirshfeld surface mapped over d_norm in Fig. 3 are due to a short interatomic C⋯C contact (see Table 2), significant in the crystal of (I). The absence of characteristic red spots near other atoms on the d_norm-mapped Hirshfeld surface confirms the absence of conventional hydrogen bonds in the structure except for a weak C—H⋯O interaction as given in Table 1. The blue and red regions corresponding to positive and negative electrostatic potentials on the Hirshfeld surface mapped over electrostatic potential, in Fig. 4 are the result of polarization of charges localized near the atoms. The immediate environments about a reference molecule within shape-index-mapped Hirshfeld surfaces highlighting intermolecular C—H⋯O interactions, short interatomic O⋯H/H⋯O contacts, π–π stacking interactions and C—Cl⋯π contacts are illustrated in Fig. 5.

Table 2
Summary of short interatomic contacts (Å) in (I)

Contact	distance	symmetry operation
H5⋯H11	2.27	x, $[{1\over 2}]$ − y, $[{1\over 2}]$ + z
O2⋯H5	2.70	-x, − $[{1\over 2}]$ + y, $[{1\over 2}]$ − z
O3⋯H9	2.70	-x, − $[{1\over 2}]$ + y, $[{1\over 2}]$ − z
C7⋯C18	3.346 (3)	−1 + x, y, z

Figure 3
Two views of the Hirshfeld surface for (I)

plotted over d_norm in the range −0.032 to 1.401 au.

Figure 4
A view of Hirshfeld surface for (I)

mapped over the calculated electrostatic potential in the range −0.067 to + 0.039 au. The red and blue regions represent negative and positive electrostatic potentials, respectively.

Figure 5
Views of Hirshfeld surfaces mapped over the shape-index about a reference molecule, showing (a) C—H⋯O and short interatomic O⋯H/H⋯O contacts by black and red dashed lines, respectively, (b) π–π stacking interactions between naphthyl residues and between chlorobenzene and naphthyl rings by blue and yellow dotted lines, respectively and (c) C—Cl⋯π/π⋯Cl—C stacking contacts between chlorobenzene rings with black and blue dotted lines.

The overall two-dimensional fingerprint plot (Fig. 6a) and those delineated into H⋯H, O⋯H/H⋯O, Cl⋯H/H⋯Cl, C⋯C, C⋯H/H⋯C, C⋯Cl/Cl⋯C and Cl⋯O/O⋯Cl contacts (McKinnon et al., 2007 ) are illustrated in Fig. 6b–h, respectively; the relative contributions from the various contacts to the Hirshfeld surfaces are summarized in Table 3. The relatively low, i.e. 35.9%, contribution from H⋯H contacts to the Hirshfeld surface of (I) is due to the low content of hydrogen atoms in the molecule and the involvement of some hydrogen atoms in short interatomic O⋯H/H⋯O contacts (Tables 1 and 2). The single peak at d_e + d_i ∼2.3 Å in Fig. 6b is the result of a short interatomic H⋯H contact (Table 2). The intermolecular C—H⋯O interaction in the crystal is recognized as the pair of peaks at d_e + d_i ∼2.6 Å in the O⋯H/H⋯O delineated fingerprint plot (Fig. 6c); the points arising from the short interatomic O⋯H contacts are merged in the plot.

Table 3
Percentage contributions of interatomic contacts to the Hirshfeld surfaces for (I)

Contact	percentage contribution
H⋯H	35.9
O⋯H/H⋯O	18.2
Cl⋯H/H⋯Cl	10.6
C⋯H/H⋯C	9.0
C⋯C	9.9
Se⋯H/H⋯Se	4.2
Se⋯C/C⋯Se	3.0
C⋯Cl/Cl⋯C	3.0
C⋯O/O⋯C	2.6
Cl⋯O/O⋯Cl	2.5
Se⋯Cl/Cl⋯Se	0.6
Se⋯O/O⋯Se	0.5

Figure 6
(a) The full two-dimensional fingerprint plot for (I)

and fingerprint plots delineated into (b) H⋯H, (c) O⋯H/H⋯O, (d) Cl⋯H/H⋯Cl, (e) C⋯C, (f) C⋯H/H⋯C, (g) C⋯Cl/Cl⋯C and (h) Cl⋯O/O⋯Cl contacts.

The fingerprint plot delineated into C⋯C contacts, Fig. 6e, characterizes the two π–π stacking interactions, one between inversion-related naphthyl rings, and the other between the chlorobenzene and (C2–C4/C9–C11) rings as the two overlapping triangular regions at around d_e = d_i ∼1.8 and 1.9 Å, respectively, having green points in the overlapping portion. The presence of these two π–π stacking interactions is also seen in the flat regions around the participating rings labelled with 1, 2 and 3 in the Hirshfeld surface mapped over curvedness in Fig. 7.

Figure 7
View of the Hirshfeld surface mapped over curvedness highlighting the flat regions corresponding to the C2–C4/C9–C11, C3–C8 and C14–C19 rings, labelled as 1, 2 and 3, respectively, involved in π–π stacking interactions.

The chlorine atom on the benzene (C14–C19) ring makes a useful contribution to the molecular packing. The small, i.e. 3.0%, contribution from C⋯Cl/Cl⋯C contacts (Fig. 6g) to the Hirshfeld surface is the result of its involvement in a C—Cl⋯π contact formed between symmetry-related chlorobenzene atoms (Fig. 5c). Its presence is also clear from the fingerprint plot delineated into Cl⋯H/H⋯Cl (Fig. 6d), and Cl⋯O/O⋯Cl contacts (Fig. 6h). The contribution from C⋯H/H⋯C contacts (Fig. 6f) and other contacts (Table 3), including the selenium atom, have negligible influence on the packing as the interatomic separations are greater than sum of their respective van der Waals radii.

5. Database survey

There are three structures in the crystallographic literature (Groom et al., 2016 ) having a similar 2-(organylselanyl)oxane framework as in (I). The chemical diagrams for these, i.e. (II) (Traar et al., 2004 ), (III) (Woodward et al., 2010 ) and (IV) (McDonagh et al., 2016 ) are shown in the Scheme above. Each of the structures features an intramolecular Se⋯O interaction as in (I). From the data collated in Table 4, there is no correlation between the Se⋯O distance and the C—Se—C angle, consistent with the weak nature of these interactions.

Table 4
Summary of Se⋯O distances (Å) and C—Se—C bond angles (°) in (I)–(IV)

Compound	Se⋯O	C—Se—C	Ref.
(I)	2.8122 (13)	95.62 (8)	this work
(II)	2.7429 (18)	98.43 (12)	Traar et al. (2004)
(III)	2.8760 (12)	98.16 (8)	Woodward et al. (2010)
(IV)	2.8606 (19)	97.41 (12)	McDonagh et al. (2016)

6. Synthesis and crystallization

Referring to the reaction scheme, in a double-necked flask equipped with a magnetic bar and reflux condenser, under a nitrogen atmosphere, lawsone (1 mmol, 174 mg), paraformaldehyde (8 mmol, 240 mg), the vinyl selenide (1.5 mmol, 326 mg) and the ionic liquid 1-butyl-3-methylimidazolium chloride, [Bmim]Cl (1 mmol, 175 mg) were added over 1,4-dioxane (2 ml). The reaction mixture was heated at 383 K and stirred over 2 h. The reaction mixture was cooled and diluted with dichloromethane (100 ml) and then washed with water (3 × 50 ml). The organic phase was dried over Na₂SO₄, filtered and concentrated under vacuum. The crude product was purified in a silica gel-packed chromatography column, using ethyl acetate and hexane (2:8) as eluent to afford α-lapachone and β-lapachone (I) derivatives in 80% yield. Crystals of (I) were obtained by slow evaporation of a solvent mixture of hexane and ethyl acetate (8:2).

7. Refinement details

Crystal data, data collection and structure refinement details are summarized in Table 5. The carbon-bound H atoms were placed in calculated positions (C—H = 0.93–0.98 Å) and were included in the refinement in the riding-model approximation, with U_iso(H) set to 1.2U_eq(C).

Table 5
Experimental details

Crystal data
Chemical formula	C₁₉H₁₃ClO₃Se
M_r	403.70
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	7.3757 (3), 13.7306 (5), 16.4473 (6)
β (°)	100.002 (1)
V (Å³)	1640.35 (11)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	2.47
Crystal size (mm)	0.40 × 0.33 × 0.27

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996 )
T_min, T_max	0.484, 0.745
No. of measured, independent and observed [I > 2σ(I)] reflections	38518, 3367, 2984
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.626

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.026, 0.068, 1.03
No. of reflections	3367
No. of parameters	217
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.36, −0.39
Computer programs: APEX2 and SAINT (Bruker, 2009 ), SIR2014 (Burla et al., 2015 ), SHELXL2014 (Sheldrick, 2015 ), ORTEP-3 for Windows (Farrugia, 2012 ), DIAMOND (Brandenburg, 2006 ) and publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 1551641

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S2056989017007605/wm5392sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989017007605/wm5392Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2056989017007605/wm5392Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SIR2014 (Burla et al., 2015); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

2-[(4-Chlorophenyl)selanyl]-3,4-dihydro-2H-benzo[h]chromene-5,6-dione top

Crystal data top

C₁₉H₁₃ClO₃Se	F(000) = 808
M_r = 403.70	D_x = 1.635 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 7.3757 (3) Å	Cell parameters from 9049 reflections
b = 13.7306 (5) Å	θ = 2.5–26.3°
c = 16.4473 (6) Å	µ = 2.47 mm⁻¹
β = 100.002 (1)°	T = 293 K
V = 1640.35 (11) Å³	Irregular, colourless
Z = 4	0.40 × 0.33 × 0.27 mm

Data collection top

Bruker APEXII CCD diffractometer	2984 reflections with I > 2σ(I)
φ and ω scans	R_int = 0.031
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	θ_max = 26.4°, θ_min = 1.9°
T_min = 0.484, T_max = 0.745	h = −9→9
38518 measured reflections	k = −17→17
3367 independent reflections	l = −20→20

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.026	H-atom parameters constrained
wR(F²) = 0.068	w = 1/[σ²(F_o²) + (0.0329P)² + 0.739P] where P = (F_o² + 2F_c²)/3
S = 1.03	(Δ/σ)_max = 0.001
3367 reflections	Δρ_max = 0.36 e Å⁻³
217 parameters	Δρ_min = −0.39 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
Se1	0.50950 (3)	0.20340 (2)	0.19075 (2)	0.05076 (8)
Cl1	0.74491 (12)	0.48216 (7)	−0.08524 (6)	0.0988 (3)
O1	0.14227 (17)	0.24860 (9)	0.12331 (8)	0.0427 (3)
O2	−0.2776 (2)	−0.07713 (12)	0.09235 (12)	0.0741 (5)
O3	−0.0776 (2)	−0.03054 (10)	0.24246 (10)	0.0628 (4)
C1	0.2739 (3)	0.26958 (13)	0.19618 (12)	0.0429 (4)
H9	0.2967	0.3399	0.1975	0.051*
C2	0.0406 (2)	0.16654 (12)	0.12272 (11)	0.0362 (4)
C3	−0.0687 (2)	0.14639 (13)	0.04065 (11)	0.0389 (4)
C4	−0.1805 (2)	0.06325 (14)	0.02911 (12)	0.0432 (4)
C5	−0.2841 (3)	0.04307 (17)	−0.04809 (13)	0.0563 (5)
H4	−0.3567	−0.0127	−0.0558	0.068*
C6	−0.2792 (3)	0.1060 (2)	−0.11328 (13)	0.0644 (6)
H3	−0.3499	0.0930	−0.1647	0.077*
C7	−0.1698 (3)	0.18762 (19)	−0.10224 (13)	0.0601 (6)
H2	−0.1675	0.2297	−0.1464	0.072*
C8	−0.0625 (3)	0.20824 (16)	−0.02611 (12)	0.0491 (5)
H1	0.0129	0.2630	−0.0197	0.059*
C9	−0.1868 (2)	−0.00345 (14)	0.09908 (13)	0.0468 (4)
C10	−0.0715 (3)	0.02303 (13)	0.18356 (12)	0.0431 (4)
C11	0.0400 (2)	0.10986 (13)	0.19024 (11)	0.0387 (4)
C12	0.1505 (3)	0.13595 (14)	0.27303 (11)	0.0479 (4)
H7	0.2611	0.0965	0.2838	0.057*
H8	0.0787	0.1232	0.3160	0.057*
C13	0.2018 (3)	0.24304 (14)	0.27349 (12)	0.0502 (5)
H6	0.0945	0.2824	0.2774	0.060*
H5	0.2952	0.2568	0.3214	0.060*
C14	0.5784 (2)	0.28761 (13)	0.10819 (12)	0.0433 (4)
C15	0.7139 (3)	0.35717 (15)	0.13040 (13)	0.0508 (5)
H13	0.7709	0.3629	0.1853	0.061*
C16	0.7646 (3)	0.41802 (17)	0.07156 (16)	0.0599 (6)
H12	0.8567	0.4642	0.0862	0.072*
C17	0.6774 (3)	0.40953 (17)	−0.00896 (15)	0.0587 (5)
C18	0.5413 (3)	0.3415 (2)	−0.03203 (14)	0.0617 (6)
H11	0.4824	0.3374	−0.0867	0.074*
C19	0.4930 (3)	0.27935 (17)	0.02638 (13)	0.0527 (5)
H10	0.4034	0.2320	0.0110	0.063*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Se1	0.04595 (13)	0.04744 (13)	0.05540 (14)	0.00547 (8)	−0.00095 (9)	0.00375 (9)
Cl1	0.0924 (5)	0.1005 (6)	0.1134 (6)	0.0119 (4)	0.0452 (5)	0.0443 (5)
O1	0.0412 (6)	0.0388 (7)	0.0471 (7)	−0.0011 (5)	0.0046 (5)	0.0103 (6)
O2	0.0652 (10)	0.0486 (9)	0.0975 (13)	−0.0140 (8)	−0.0167 (9)	0.0100 (9)
O3	0.0868 (11)	0.0421 (8)	0.0603 (9)	−0.0118 (7)	0.0148 (8)	0.0101 (7)
C1	0.0477 (10)	0.0305 (8)	0.0495 (10)	0.0001 (7)	0.0056 (8)	−0.0003 (7)
C2	0.0341 (8)	0.0329 (8)	0.0423 (9)	0.0067 (7)	0.0089 (7)	0.0021 (7)
C3	0.0326 (8)	0.0434 (10)	0.0416 (9)	0.0118 (7)	0.0088 (7)	0.0006 (7)
C4	0.0345 (9)	0.0446 (10)	0.0495 (10)	0.0117 (7)	0.0048 (7)	−0.0050 (8)
C5	0.0427 (10)	0.0635 (13)	0.0594 (13)	0.0102 (9)	0.0000 (9)	−0.0145 (11)
C6	0.0501 (12)	0.0963 (19)	0.0437 (11)	0.0186 (13)	−0.0001 (9)	−0.0120 (12)
C7	0.0515 (12)	0.0891 (17)	0.0410 (11)	0.0183 (12)	0.0114 (9)	0.0091 (11)
C8	0.0411 (10)	0.0638 (13)	0.0441 (10)	0.0113 (9)	0.0120 (8)	0.0081 (9)
C9	0.0374 (9)	0.0356 (9)	0.0653 (12)	0.0056 (8)	0.0027 (8)	0.0003 (9)
C10	0.0470 (10)	0.0315 (9)	0.0522 (11)	0.0048 (7)	0.0124 (8)	0.0033 (8)
C11	0.0433 (9)	0.0320 (9)	0.0412 (9)	0.0048 (7)	0.0085 (7)	0.0017 (7)
C12	0.0645 (12)	0.0391 (10)	0.0395 (10)	−0.0009 (9)	0.0076 (9)	0.0026 (8)
C13	0.0664 (13)	0.0386 (10)	0.0458 (10)	−0.0005 (9)	0.0105 (9)	−0.0047 (8)
C14	0.0349 (9)	0.0438 (10)	0.0498 (10)	0.0029 (7)	0.0030 (8)	−0.0071 (8)
C15	0.0432 (10)	0.0541 (12)	0.0536 (11)	−0.0039 (9)	0.0042 (9)	−0.0153 (9)
C16	0.0515 (12)	0.0505 (12)	0.0804 (16)	−0.0078 (10)	0.0189 (11)	−0.0138 (11)
C17	0.0529 (12)	0.0560 (13)	0.0719 (14)	0.0120 (10)	0.0240 (11)	0.0099 (11)
C18	0.0489 (12)	0.0858 (17)	0.0489 (12)	0.0057 (11)	0.0041 (9)	0.0033 (11)
C19	0.0401 (10)	0.0636 (13)	0.0514 (11)	−0.0060 (9)	−0.0006 (9)	−0.0093 (10)

Geometric parameters (Å, º) top

Se1—C14	1.918 (2)	C7—H2	0.9300
Se1—C1	1.9769 (19)	C8—H1	0.9300
Cl1—C17	1.742 (2)	C9—C10	1.541 (3)
O1—C2	1.353 (2)	C10—C11	1.442 (3)
O1—C1	1.434 (2)	C11—C12	1.504 (3)
O2—C9	1.208 (2)	C12—C13	1.518 (3)
O3—C10	1.223 (2)	C12—H7	0.9700
C1—C13	1.505 (3)	C12—H8	0.9700
C1—H9	0.9800	C13—H6	0.9700
C2—C11	1.357 (2)	C13—H5	0.9700
C2—C3	1.473 (2)	C14—C15	1.385 (3)
C3—C8	1.395 (3)	C14—C19	1.388 (3)
C3—C4	1.401 (3)	C15—C16	1.379 (3)
C4—C5	1.392 (3)	C15—H13	0.9300
C4—C9	1.478 (3)	C16—C17	1.373 (3)
C5—C6	1.382 (3)	C16—H12	0.9300
C5—H4	0.9300	C17—C18	1.376 (3)
C6—C7	1.375 (4)	C18—C19	1.377 (3)
C6—H3	0.9300	C18—H11	0.9300
C7—C8	1.389 (3)	C19—H10	0.9300

C14—Se1—C1	95.62 (8)	C11—C10—C9	118.81 (16)
C2—O1—C1	117.85 (13)	C2—C11—C10	119.65 (17)
O1—C1—C13	111.73 (16)	C2—C11—C12	121.77 (17)
O1—C1—Se1	110.03 (12)	C10—C11—C12	118.57 (16)
C13—C1—Se1	111.65 (13)	C11—C12—C13	109.32 (15)
O1—C1—H9	107.7	C11—C12—H7	109.8
C13—C1—H9	107.7	C13—C12—H7	109.8
Se1—C1—H9	107.7	C11—C12—H8	109.8
O1—C2—C11	123.53 (16)	C13—C12—H8	109.8
O1—C2—C3	112.17 (14)	H7—C12—H8	108.3
C11—C2—C3	124.29 (16)	C1—C13—C12	110.77 (16)
C8—C3—C4	119.21 (18)	C1—C13—H6	109.5
C8—C3—C2	121.29 (17)	C12—C13—H6	109.5
C4—C3—C2	119.49 (16)	C1—C13—H5	109.5
C5—C4—C3	120.19 (19)	C12—C13—H5	109.5
C5—C4—C9	120.03 (19)	H6—C13—H5	108.1
C3—C4—C9	119.78 (17)	C15—C14—C19	119.8 (2)
C6—C5—C4	119.9 (2)	C15—C14—Se1	119.79 (15)
C6—C5—H4	120.0	C19—C14—Se1	120.39 (15)
C4—C5—H4	120.0	C16—C15—C14	120.3 (2)
C7—C6—C5	120.1 (2)	C16—C15—H13	119.9
C7—C6—H3	120.0	C14—C15—H13	119.9
C5—C6—H3	120.0	C17—C16—C15	119.1 (2)
C6—C7—C8	121.0 (2)	C17—C16—H12	120.4
C6—C7—H2	119.5	C15—C16—H12	120.4
C8—C7—H2	119.5	C16—C17—C18	121.4 (2)
C7—C8—C3	119.6 (2)	C16—C17—Cl1	120.10 (19)
C7—C8—H1	120.2	C18—C17—Cl1	118.46 (19)
C3—C8—H1	120.2	C17—C18—C19	119.6 (2)
O2—C9—C4	122.67 (19)	C17—C18—H11	120.2
O2—C9—C10	119.38 (19)	C19—C18—H11	120.2
C4—C9—C10	117.95 (16)	C18—C19—C14	119.8 (2)
O3—C10—C11	122.40 (18)	C18—C19—H10	120.1
O3—C10—C9	118.79 (17)	C14—C19—H10	120.1

C2—O1—C1—C13	−38.2 (2)	O2—C9—C10—C11	178.44 (18)
C2—O1—C1—Se1	86.38 (16)	C4—C9—C10—C11	−1.4 (2)
C1—O1—C2—C11	8.4 (2)	O1—C2—C11—C10	−179.37 (15)
C1—O1—C2—C3	−171.67 (14)	C3—C2—C11—C10	0.7 (3)
O1—C2—C3—C8	−0.4 (2)	O1—C2—C11—C12	1.8 (3)
C11—C2—C3—C8	179.55 (17)	C3—C2—C11—C12	−178.14 (16)
O1—C2—C3—C4	179.30 (14)	O3—C10—C11—C2	−179.78 (18)
C11—C2—C3—C4	−0.8 (2)	C9—C10—C11—C2	0.4 (3)
C8—C3—C4—C5	−0.1 (3)	O3—C10—C11—C12	−0.9 (3)
C2—C3—C4—C5	−179.83 (16)	C9—C10—C11—C12	179.28 (16)
C8—C3—C4—C9	179.35 (16)	C2—C11—C12—C13	18.3 (3)
C2—C3—C4—C9	−0.3 (2)	C10—C11—C12—C13	−160.59 (17)
C3—C4—C5—C6	−1.0 (3)	O1—C1—C13—C12	57.9 (2)
C9—C4—C5—C6	179.49 (18)	Se1—C1—C13—C12	−65.84 (19)
C4—C5—C6—C7	1.0 (3)	C11—C12—C13—C1	−46.3 (2)
C5—C6—C7—C8	0.2 (3)	C19—C14—C15—C16	−0.2 (3)
C6—C7—C8—C3	−1.4 (3)	Se1—C14—C15—C16	179.92 (16)
C4—C3—C8—C7	1.3 (3)	C14—C15—C16—C17	0.9 (3)
C2—C3—C8—C7	−178.99 (17)	C15—C16—C17—C18	−0.3 (3)
C5—C4—C9—O2	1.0 (3)	C15—C16—C17—Cl1	−177.47 (16)
C3—C4—C9—O2	−178.48 (19)	C16—C17—C18—C19	−1.0 (3)
C5—C4—C9—C10	−179.15 (16)	Cl1—C17—C18—C19	176.26 (17)
C3—C4—C9—C10	1.4 (2)	C17—C18—C19—C14	1.6 (3)
O2—C9—C10—O3	−1.4 (3)	C15—C14—C19—C18	−1.1 (3)
C4—C9—C10—O3	178.77 (17)	Se1—C14—C19—C18	178.81 (16)

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C14–C19 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C13—H6···O3ⁱ	0.97	2.59	3.239 (2)	125
C17—Cl1···Cg1ⁱⁱ	1.74 (1)	3.72 (1)	4.000 (2)	86 (1)

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

Summary of short interatomic contacts (Å) in (I) top

Contact	distance	symmetry operation
H5···H11	2.27	x, 1/2 - y, 1/2 + z
O2···H5	2.70	-x, -1/2 + y, 1/2 - z
O3···H9	2.70	-x, -1/2 + y, 1/2 - z
C7···C18	3.346 (3)	-1 + x, y, z

Percentage contributions of interatomic contacts to the Hirshfeld surfaces for (I) top

Contact	percentage contribution
H···H	35.9
O···H/H···O	18.2
Cl···H/H···Cl	10.6
C···H/H···C	9.0
C···C	9.9
Se···H/H···Se	4.2
Se···C/C···Se	3.0
C···Cl/Cl···C	3.0
C···O/O···C	2.6
Cl···O/O···Cl	2.5
Se···Cl/Cl···Se	0.6
Se···O/O···Se	0.5

Summary of Se···O distances (Å) and C—Se—C bond angles (°) in (I)–(IV) top

Compound	Se···O	C—Se—C	Ref.
(I)	2.8122 (13)	95.62 (8)	this work
(II)	2.7429 (18)	98.43 (12)	Traar et al. (2004)
(III)	2.8760 (12)	98.16 (8)	Woodward et al. (2010)
(IV)	2.8606 (19)	97.41 (12)	McDonagh et al. (2016)

Acknowledgements

The Brazilian agency National Council for Scientific and Technological Development, CNPq, is gratefully acknowledged for a scholarship to JZ-S (305626/2013–2).

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