N-(4-Chloro­phen­yl)-2,4-dimethyl­benzene­sulfonamide

Shakuntala, K.; Foro, S.; Gowda, B.T.

doi:10.1107/S1600536811029795

organic compounds

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ISSN: 2056-9890

Volume 67| Part 8| August 2011| Page o2160

doi:10.1107/S1600536811029795

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N-(4-Chlorophenyl)-2,4-dimethylbenzenesulfonamide

K. Shakuntala,^a Sabine Foro ^b and B. Thimme Gowda ^a ^*

^aDepartment of Chemistry, Mangalore University, Mangalagangotri 574 199, Mangalore, India, and ^bInstitute of Materials Science, Darmstadt University of Technology, Petersenstrasse 23, D-64287 Darmstadt, Germany
^*Correspondence e-mail: gowdabt@yahoo.com

(Received 22 July 2011; accepted 22 July 2011; online 30 July 2011)

Molecules of the title compound, C₁₄H₁₄ClNO₂S, are bent at the S atom with a C—SO₂—NH—C torsion angle of 57.7 (2)°. The benzene rings are rotated relative to each other by 68.1 (1)°. In the crystal, N—H⋯O(S) hydrogen bonds pack the molecules into infinite chains parallel to the b axis.

Related literature

For the hydrogen-bonding preferences of sulfonamides, see: Adsmond & Grant (2001 ). For studies on the effects of substituents on the structures and other aspects of N-(aryl)-amides, see: Arjunan et al. (2004 ); Gowda et al. (1999 ); for N-(aryl)-methanesulfonamides, see: Gowda et al. (2007 ); and for N-(aryl)-arylsulfonamides, see: Gelbrich et al. (2007 ); Gowda et al. (2010 ); Perlovich et al. (2006 ); Shakuntala et al. (2011 ). For the preparation of the title compound, see: Savitha & Gowda (2006 ).

Experimental

Crystal data

C₁₄H₁₄ClNO₂S
M_r = 295.77
Monoclinic, P 2₁ /c
a = 9.1093 (8) Å
b = 9.9106 (9) Å
c = 16.142 (1) Å
β = 96.505 (9)°
V = 1447.9 (2) Å³
Z = 4
Mo Kα radiation
μ = 0.41 mm⁻¹
T = 293 K
0.30 × 0.20 × 0.10 mm

Data collection

Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]$ ) T_min = 0.888, T_max = 0.961
5342 measured reflections
2934 independent reflections
2219 reflections with I > 2σ(I)
R_int = 0.013

Refinement

R[F² > 2σ(F²)] = 0.049
wR(F²) = 0.121
S = 1.08
2934 reflections
177 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.28 e Å⁻³
Δρ_min = −0.32 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1N⋯O2ⁱ	0.83 (2)	2.08 (2)	2.891 (4)	166 (3)
Symmetry code: (i) $[-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Data collection: CrysAlis CCD (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]$ ); cell refinement: CrysAlis RED (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, Oxfordshire, England.]$ ); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811029795/bt5589sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811029795/bt5589Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811029795/bt5589Isup3.cml

checkCIF report

Comment top

The amide and sulfonamide moieties are the constituents of many biologically significant compounds. The hydrogen bonding preferences of sulfonamides have been investigated (Adsmond & Grant, 2001). As part of our work on the substituent effects on the structures and other aspects of N-(aryl)-amides (Arjunan et al., 2004; Gowda et al., 1999), N-(aryl)-methanesulfonamides (Gowda et al., 2007) and N-(aryl)-arylsulfonamides (Gowda et al., 2010; Shakuntala et al., 2011), in the present work, the crystal structure of N-(4-chlorophenyl)-2,4-dimethylbenzenesulfonamide (I) has been determined (Fig. 1). The N—C bond in the C—SO₂—NH—C segment has gauche torsions with respect to the S═O bonds. The molecule is bent at the S atom with the C1—SO₂—NH—C7 torsion angle of 57.7 (2)°, compared to the values of -54.9 (2)° in N-(2-chlorophenyl)- 2,4-dimethylbenzenesulfonamide (II)(Gowda et al., 2010) and 44.6 (2)° in N-(3-chlorophenyl)-2,4-dimethylbenzenesulfonamide (III) (Shakuntala et al., 2011).

The two benzene rings in (I) are tilted relative to each other by 68.1 (1)°, compared to the value of 66.2 (1)° (II) and 75.7 (1)° in (III). The other bond parameters in (I) are similar to those observed in (II), (III) and other aryl sulfonamides (Perlovich et al., 2006; Gelbrich et al., 2007).

The crystal packing of molecules in (I) via N—H···O(S) hydrogen bonds (Table 1) is shown in Fig.2.

Related literature top

For the hydrogen-bonding preferences of sulfonamides, see: Adsmond & Grant (2001). For studies on the effects of substituents on the structures and other aspects of N-(aryl)-amides, see: Arjunan et al. (2004); Gowda et al. (1999); for N-(aryl)-methanesulfonamides, see: Gowda et al. (2007); and for N-(aryl)-arylsulfonamides, see: Gelbrich et al. (2007); Gowda et al. (2010); Perlovich et al. (2006); Shakuntala et al. (2011). For the preparation of the title compound, see: Savitha & Gowda (2006).

Experimental top

The solution of 1,3-xylene (1,3-dimethylbenzene) (10 ml) in chloroform (40 ml) was treated dropwise with chlorosulfonic acid (25 ml) at 0 ° C. After the initial evolution of hydrogen chloride subsided, the reaction mixture was brought to room temperature and poured into crushed ice in a beaker. The chloroform layer was separated, washed with cold water and allowed to evaporate slowly. The residual 2,4-dimethylbenzenesulfonylchloride was treated with 4-chloroaniline in the stoichiometric ratio and boiled for ten minutes. The reaction mixture was then cooled to room temperature and added to ice cold water (100 cc). The resultant solid N-(4-chlorophenyl)-2,4-dimethylbenzenesulfonamide was filtered under suction and washed thoroughly with cold water. It was then recrystallized to constant melting point from dilute ethanol. The purity of the compound was checked and characterized by recording its infrared and NMR spectra (Savitha & Gowda, 2006).

The prism like colourless single crystals used in X-ray diffraction studies were grown in ethanolic solution by a slow evaporation at room temperature.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell refinement: CrysAlis RED (Oxford Diffraction, 2009); data reduction: CrysAlis RED (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. Molecular structure of (I), showing the atom labelling scheme and displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. Molecular packing of (I) with hydrogen bonding shown as dashed lines.

N-(4-Chlorophenyl)-2,4-dimethylbenzenesulfonamide top

Crystal data top

C₁₄H₁₄ClNO₂S	F(000) = 616
M_r = 295.77	D_x = 1.357 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2044 reflections
a = 9.1093 (8) Å	θ = 2.5–27.7°
b = 9.9106 (9) Å	µ = 0.41 mm⁻¹
c = 16.142 (1) Å	T = 293 K
β = 96.505 (9)°	Prism, colourless
V = 1447.9 (2) Å³	0.30 × 0.20 × 0.10 mm
Z = 4

Data collection top

Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector	2934 independent reflections
Radiation source: fine-focus sealed tube	2219 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.013
Rotation method data acquisition using ω and ϕ scans	θ_max = 26.4°, θ_min = 2.5°
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009)	h = −7→11
T_min = 0.888, T_max = 0.961	k = −8→12
5342 measured reflections	l = −20→19

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)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.121	H atoms treated by a mixture of independent and constrained refinement
S = 1.08	w = 1/[σ²(F_o²) + (0.0421P)² + 0.9349P] where P = (F_o² + 2F_c²)/3
2934 reflections	(Δ/σ)_max = 0.002
177 parameters	Δρ_max = 0.28 e Å⁻³
1 restraint	Δρ_min = −0.32 e Å⁻³

Crystal data top

C₁₄H₁₄ClNO₂S	V = 1447.9 (2) Å³
M_r = 295.77	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 9.1093 (8) Å	µ = 0.41 mm⁻¹
b = 9.9106 (9) Å	T = 293 K
c = 16.142 (1) Å	0.30 × 0.20 × 0.10 mm
β = 96.505 (9)°

Data collection top

Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector	2934 independent reflections
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009)	2219 reflections with I > 2σ(I)
T_min = 0.888, T_max = 0.961	R_int = 0.013
5342 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.049	1 restraint
wR(F²) = 0.121	H atoms treated by a mixture of independent and constrained refinement
S = 1.08	Δρ_max = 0.28 e Å⁻³
2934 reflections	Δρ_min = −0.32 e Å⁻³
177 parameters

Special details top

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

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	U_iso*/U_eq
C1	0.6057 (3)	0.0526 (2)	0.39055 (15)	0.0469 (6)
C2	0.6430 (3)	0.1450 (3)	0.45485 (16)	0.0542 (6)
C3	0.7412 (3)	0.1003 (3)	0.52140 (17)	0.0641 (7)
H3	0.7676	0.1602	0.5649	0.077*
C4	0.8019 (3)	−0.0276 (3)	0.52681 (17)	0.0618 (7)
C5	0.7618 (3)	−0.1160 (3)	0.46227 (19)	0.0643 (7)
H5	0.8004	−0.2029	0.4644	0.077*
C6	0.6650 (3)	−0.0771 (3)	0.39452 (18)	0.0575 (7)
H6	0.6392	−0.1377	0.3513	0.069*
C7	0.7258 (3)	0.1399 (2)	0.21393 (14)	0.0458 (6)
C8	0.7325 (4)	0.0198 (3)	0.1716 (2)	0.0709 (8)
H8	0.6500	−0.0361	0.1639	0.085*
C9	0.8622 (4)	−0.0178 (3)	0.1404 (2)	0.0817 (10)
H9	0.8674	−0.0994	0.1125	0.098*
C10	0.9820 (4)	0.0654 (3)	0.15092 (19)	0.0696 (8)
C11	0.9774 (3)	0.1839 (3)	0.19339 (18)	0.0685 (8)
H11	1.0600	0.2396	0.2006	0.082*
C12	0.8494 (3)	0.2206 (3)	0.22558 (16)	0.0587 (7)
H12	0.8465	0.3006	0.2554	0.070*
C13	0.5833 (4)	0.2867 (3)	0.4561 (2)	0.0760 (9)
H13A	0.4795	0.2838	0.4616	0.091*
H13B	0.5985	0.3316	0.4050	0.091*
H13C	0.6338	0.3351	0.5023	0.091*
C14	0.9094 (4)	−0.0683 (4)	0.6002 (2)	0.0841 (10)
H14A	0.8563	−0.1060	0.6428	0.101*
H14B	0.9637	0.0094	0.6218	0.101*
H14C	0.9766	−0.1344	0.5829	0.101*
N1	0.5919 (2)	0.1852 (2)	0.24225 (13)	0.0504 (5)
H1N	0.587 (3)	0.2672 (18)	0.2515 (16)	0.061*
O1	0.3758 (2)	0.18577 (19)	0.31728 (13)	0.0667 (5)
O2	0.4524 (2)	−0.02597 (17)	0.25512 (12)	0.0638 (5)
Cl1	1.14202 (12)	0.01793 (12)	0.10872 (7)	0.1119 (4)
S1	0.49106 (7)	0.09643 (6)	0.29924 (4)	0.04969 (19)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0499 (14)	0.0414 (12)	0.0497 (14)	−0.0080 (10)	0.0070 (11)	0.0040 (11)
C2	0.0632 (16)	0.0511 (14)	0.0504 (14)	−0.0098 (12)	0.0154 (12)	−0.0028 (12)
C3	0.0742 (18)	0.073 (2)	0.0456 (14)	−0.0171 (16)	0.0078 (13)	−0.0035 (14)
C4	0.0549 (16)	0.078 (2)	0.0523 (15)	−0.0122 (15)	0.0074 (12)	0.0172 (15)
C5	0.0646 (17)	0.0546 (16)	0.0729 (19)	0.0027 (14)	0.0044 (14)	0.0148 (15)
C6	0.0664 (17)	0.0424 (14)	0.0621 (16)	−0.0032 (12)	0.0006 (13)	0.0024 (12)
C7	0.0602 (15)	0.0353 (12)	0.0405 (12)	0.0029 (11)	0.0000 (11)	0.0061 (10)
C8	0.079 (2)	0.0476 (16)	0.088 (2)	−0.0072 (14)	0.0195 (17)	−0.0116 (15)
C9	0.104 (3)	0.0538 (18)	0.092 (2)	0.0131 (18)	0.032 (2)	−0.0058 (17)
C10	0.0696 (19)	0.076 (2)	0.0644 (18)	0.0251 (17)	0.0137 (15)	0.0246 (16)
C11	0.0613 (18)	0.081 (2)	0.0620 (17)	−0.0025 (16)	0.0021 (14)	0.0097 (16)
C12	0.0706 (18)	0.0540 (16)	0.0496 (15)	−0.0057 (14)	−0.0011 (13)	−0.0013 (12)
C13	0.100 (2)	0.0541 (18)	0.074 (2)	−0.0043 (16)	0.0123 (18)	−0.0156 (15)
C14	0.0680 (19)	0.114 (3)	0.0679 (19)	−0.0132 (19)	−0.0022 (16)	0.0274 (19)
N1	0.0649 (13)	0.0290 (10)	0.0575 (13)	0.0021 (10)	0.0074 (10)	0.0023 (9)
O1	0.0522 (11)	0.0563 (11)	0.0919 (14)	0.0044 (9)	0.0100 (10)	0.0039 (10)
O2	0.0695 (12)	0.0422 (10)	0.0751 (13)	−0.0126 (9)	−0.0118 (10)	−0.0014 (9)
Cl1	0.0955 (7)	0.1262 (9)	0.1214 (8)	0.0489 (6)	0.0447 (6)	0.0358 (7)
S1	0.0499 (3)	0.0361 (3)	0.0616 (4)	−0.0040 (3)	−0.0001 (3)	0.0016 (3)

Geometric parameters (Å, º) top

C1—C6	1.392 (4)	C9—C10	1.363 (5)
C1—C2	1.397 (4)	C9—H9	0.9300
C1—S1	1.762 (3)	C10—C11	1.363 (5)
C2—C3	1.390 (4)	C10—Cl1	1.742 (3)
C2—C13	1.508 (4)	C11—C12	1.378 (4)
C3—C4	1.382 (4)	C11—H11	0.9300
C3—H3	0.9300	C12—H12	0.9300
C4—C5	1.378 (4)	C13—H13A	0.9600
C4—C14	1.504 (4)	C13—H13B	0.9600
C5—C6	1.380 (4)	C13—H13C	0.9600
C5—H5	0.9300	C14—H14A	0.9600
C6—H6	0.9300	C14—H14B	0.9600
C7—C12	1.377 (4)	C14—H14C	0.9600
C7—C8	1.377 (4)	N1—S1	1.630 (2)
C7—N1	1.423 (3)	N1—H1N	0.828 (17)
C8—C9	1.387 (4)	O1—S1	1.429 (2)
C8—H8	0.9300	O2—S1	1.430 (2)

C6—C1—C2	120.7 (2)	C11—C10—Cl1	120.3 (3)
C6—C1—S1	117.1 (2)	C10—C11—C12	119.5 (3)
C2—C1—S1	122.1 (2)	C10—C11—H11	120.2
C3—C2—C1	116.5 (3)	C12—C11—H11	120.2
C3—C2—C13	119.2 (3)	C7—C12—C11	120.6 (3)
C1—C2—C13	124.2 (3)	C7—C12—H12	119.7
C4—C3—C2	124.0 (3)	C11—C12—H12	119.7
C4—C3—H3	118.0	C2—C13—H13A	109.5
C2—C3—H3	118.0	C2—C13—H13B	109.5
C5—C4—C3	117.7 (3)	H13A—C13—H13B	109.5
C5—C4—C14	121.2 (3)	C2—C13—H13C	109.5
C3—C4—C14	121.1 (3)	H13A—C13—H13C	109.5
C4—C5—C6	120.8 (3)	H13B—C13—H13C	109.5
C4—C5—H5	119.6	C4—C14—H14A	109.5
C6—C5—H5	119.6	C4—C14—H14B	109.5
C5—C6—C1	120.3 (3)	H14A—C14—H14B	109.5
C5—C6—H6	119.9	C4—C14—H14C	109.5
C1—C6—H6	119.9	H14A—C14—H14C	109.5
C12—C7—C8	119.2 (3)	H14B—C14—H14C	109.5
C12—C7—N1	119.4 (2)	C7—N1—S1	124.70 (17)
C8—C7—N1	121.4 (2)	C7—N1—H1N	115.6 (19)
C7—C8—C9	120.0 (3)	S1—N1—H1N	112.6 (19)
C7—C8—H8	120.0	O1—S1—O2	118.81 (12)
C9—C8—H8	120.0	O1—S1—N1	104.76 (12)
C10—C9—C8	119.7 (3)	O2—S1—N1	107.43 (12)
C10—C9—H9	120.2	O1—S1—C1	111.24 (12)
C8—C9—H9	120.2	O2—S1—C1	107.25 (12)
C9—C10—C11	120.9 (3)	N1—S1—C1	106.67 (11)
C9—C10—Cl1	118.8 (3)

C6—C1—C2—C3	0.2 (4)	C8—C9—C10—Cl1	−178.3 (3)
S1—C1—C2—C3	−176.34 (19)	C9—C10—C11—C12	−0.5 (4)
C6—C1—C2—C13	−179.5 (3)	Cl1—C10—C11—C12	179.3 (2)
S1—C1—C2—C13	4.0 (4)	C8—C7—C12—C11	1.8 (4)
C1—C2—C3—C4	0.0 (4)	N1—C7—C12—C11	−175.2 (2)
C13—C2—C3—C4	179.7 (3)	C10—C11—C12—C7	−1.2 (4)
C2—C3—C4—C5	−0.3 (4)	C12—C7—N1—S1	−130.2 (2)
C2—C3—C4—C14	179.1 (3)	C8—C7—N1—S1	52.9 (3)
C3—C4—C5—C6	0.4 (4)	C7—N1—S1—O1	175.7 (2)
C14—C4—C5—C6	−178.9 (3)	C7—N1—S1—O2	−57.0 (2)
C4—C5—C6—C1	−0.3 (4)	C7—N1—S1—C1	57.7 (2)
C2—C1—C6—C5	0.0 (4)	C6—C1—S1—O1	146.0 (2)
S1—C1—C6—C5	176.6 (2)	C2—C1—S1—O1	−37.4 (2)
C12—C7—C8—C9	−0.8 (4)	C6—C1—S1—O2	14.5 (2)
N1—C7—C8—C9	176.1 (3)	C2—C1—S1—O2	−168.8 (2)
C7—C8—C9—C10	−0.9 (5)	C6—C1—S1—N1	−100.3 (2)
C8—C9—C10—C11	1.5 (5)	C2—C1—S1—N1	76.3 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O2ⁱ	0.83 (2)	2.08 (2)	2.891 (4)	166 (3)

Symmetry code: (i) −x+1, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formula	C₁₄H₁₄ClNO₂S
M_r	295.77
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	9.1093 (8), 9.9106 (9), 16.142 (1)
β (°)	96.505 (9)
V (Å³)	1447.9 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.41
Crystal size (mm)	0.30 × 0.20 × 0.10

Data collection
Diffractometer	Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2009)
T_min, T_max	0.888, 0.961
No. of measured, independent and observed [I > 2σ(I)] reflections	5342, 2934, 2219
R_int	0.013
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.049, 0.121, 1.08
No. of reflections	2934
No. of parameters	177
No. of restraints	1
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.28, −0.32

Computer programs: CrysAlis CCD (Oxford Diffraction, 2009), CrysAlis RED (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O2ⁱ	0.828 (17)	2.082 (18)	2.891 (4)	166 (3)

Symmetry code: (i) −x+1, y+1/2, −z+1/2.

Acknowledgements

KS thanks the University Grants Commission, Government of India, New Delhi, for the award of a research fellowship under its faculty improvement programme.

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