1-Ethyl-4-[1-(1-phenyl­ethyl­idene)hydrazin-2-yl­idene]-3,4-dihydro-1H-2λ6,1-benzothia­zine-2,2-dione

Shafiq, M.; Khan, I.U.; Arshad, M.N.; Bukhari, I.H.; Ejaz

doi:10.1107/S1600536812022982

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 68| Part 6| June 2012| Page o1927

doi:10.1107/S1600536812022982

Open

access

1-Ethyl-4-[1-(1-phenylethylidene)hydrazin-2-ylidene]-3,4-dihydro-1H-2λ⁶,1-benzothiazine-2,2-dione

Muhammad Shafiq,^a ^* Islam Ullah Khan,^b Muhammad Nadeem Arshad,^c Iftikhar Hussain Bukhari ^a and Ejaz ^b

^aDepartment of Chemistry, Government College University, Faisalabad 38040, Pakistan, ^bMaterials Chemistry Laboratory, Department of Chemistry, GC University, Lahore 54000, Pakistan, and ^cDepartment of Chemistry, University of Gujrat, Gujrat 50781, Pakistan
^*Correspondence e-mail: hafizshafique@hotmail.com

(Received 13 May 2012; accepted 19 May 2012; online 31 May 2012)

In the title compound, C₁₈H₁₉N₃O₂S, the thiazine ring adopts an envelope conformation, with the S atom displaced by 0.732 (1) Å from the other atoms of the ring. The phenyl ring is oriented at a dihedral angle of 79.33 (7)° with respect to the fused benzene ring. The conformations about the two double bonds in the R₂C=N—N=C(CH₃)Ar grouping are Z and E, respectively. In the crystal, inversion dimers linked by pairs of C—H⋯O interactions generate R₂²(8) and R₂²(12) loops, as parts of infinite chains along the a-axis direction.

Related literature

For related structures and further synthetic details, see: Shafiq et al. (2011a ,b ). For ring puckering parameters, see: Cremer & Pople (1975 ).

Experimental

Crystal data

C₁₈H₁₉N₃O₂S
M_r = 341.42
Monoclinic, P 2₁ /n
a = 9.7278 (3) Å
b = 12.4327 (3) Å
c = 14.2607 (4) Å
β = 100.725 (1)°
V = 1694.60 (8) Å³
Z = 4
Mo Kα radiation
μ = 0.21 mm⁻¹
T = 296 K
0.41 × 0.08 × 0.06 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2007 ) T_min = 0.920, T_max = 0.988
16049 measured reflections
4129 independent reflections
2887 reflections with I > 2σ(I)
R_int = 0.035

Refinement

R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.151
S = 1.00
4127 reflections
219 parameters
H-atom parameters constrained
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
C8—H8A⋯O1ⁱ	0.97	2.43	3.390 (2)	170
C16—H16B⋯O2ⁱⁱ	0.97	2.52	3.481 (2)	171
Symmetry codes: (i) -x+2, -y+2, -z+2; (ii) -x+1, -y+2, -z+2.

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; 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: WinGX (Farrugia, 1999 ) and PLATON.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812022982/hb6798sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812022982/hb6798Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812022982/hb6798Isup3.cml

checkCIF report

Comment top

As part of our ongoing studies of benzothiazines, we now describe the title compound, which is related to 4-hydrazinylidene-1-ethyl-3H-2λ⁶,1-benzothiazine-2,2-dione and 6-bromo-1-methyl-4-[2-(4-methylbenzylidene) hydrazinylidene]-3H-2λ⁶,1-benzothiazine-2,2-dione. The aromatic and thiazine rings are oriented at dihedral angle of 10.31 (9)° and thiazine ring adopted sofa shape with r. m. s. deviavtion of about 0.2213 (12)° with the maximum deviation of from the S1 (0.3686 (10)Å) & N1 (0.2640 (11)Å). Thiazine ring showes total ring puckering amplitude QT = 0.5430 Å with (θ) = 55.02 ° (π) = 358.2638 ° (Cremer & Pople, 1975). Both the oxygen atoms of SO₂ group are involved in accepting C—H···O type weak intermolecular hydrogen bonding interaction and produce two ring motifs represented as R₂²(8) & R₂²(12) (Table. 1, Fig. 2).

Related literature top

For related structures and further synthetic details, see: Shafiq et al. (2011a,b). For ring puckering parameters, see: Cremer & Pople (1975)

Experimental top

4-Hydrazinylidene-1- methyl-3H-2λ⁶,1-benzothiazine-2,2-dione (Shafiq et al., 2011a) was subjected to react with acetophenone according to literature procedure (Shafiq et al., 2011b). The product obtained was then recrystalized in ethylacetate under slow evaporation to obtain suitable crystal for diffraction studies.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); 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: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of (I) with 50% displacement ellipsoids.
	Fig. 2. Unit cell packing showes the dimers formed through C—H···O hydrogen bonds, drawn using dashed lines.

1-Ethyl-4-[1-(1-phenylethylidene)hydrazin-2-ylidene]-3,4-dihydro- 1H-2λ⁶,1-benzothiazine-2,2-dione top

Crystal data top

C₁₈H₁₉N₃O₂S	F(000) = 720
M_r = 341.42	D_x = 1.338 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 4849 reflections
a = 9.7278 (3) Å	θ = 2.4–26.1°
b = 12.4327 (3) Å	µ = 0.21 mm⁻¹
c = 14.2607 (4) Å	T = 296 K
β = 100.725 (1)°	Needle, colorless
V = 1694.60 (8) Å³	0.41 × 0.08 × 0.06 mm
Z = 4

Data collection top

Bruker Kappa APEXII CCD diffractometer	4129 independent reflections
Radiation source: fine-focus sealed tube	2887 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.035
ϕ and ω scans	θ_max = 28.3°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −12→12
T_min = 0.920, T_max = 0.988	k = −16→16
16049 measured reflections	l = −19→16

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.151	H-atom parameters constrained
S = 1.00	w = 1/[σ²(F_o²) + (0.0895P)² + 0.2125P] where P = (F_o² + 2F_c²)/3
4127 reflections	(Δ/σ)_max = 0.002
219 parameters	Δρ_max = 0.28 e Å⁻³
0 restraints	Δρ_min = −0.32 e Å⁻³

Crystal data top

C₁₈H₁₉N₃O₂S	V = 1694.60 (8) Å³
M_r = 341.42	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 9.7278 (3) Å	µ = 0.21 mm⁻¹
b = 12.4327 (3) Å	T = 296 K
c = 14.2607 (4) Å	0.41 × 0.08 × 0.06 mm
β = 100.725 (1)°

Data collection top

Bruker Kappa APEXII CCD diffractometer	4129 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2007)	2887 reflections with I > 2σ(I)
T_min = 0.920, T_max = 0.988	R_int = 0.035
16049 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	0 restraints
wR(F²) = 0.151	H-atom parameters constrained
S = 1.00	Δρ_max = 0.28 e Å⁻³
4127 reflections	Δρ_min = −0.32 e Å⁻³
219 parameters

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.

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 > 2sigma(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
S1	0.78767 (5)	0.93644 (4)	1.05780 (3)	0.04426 (17)
O1	0.85670 (16)	1.03503 (13)	1.08838 (12)	0.0650 (4)
O2	0.71460 (14)	0.88277 (12)	1.12183 (10)	0.0557 (4)
N1	0.68626 (18)	0.95785 (12)	0.95522 (11)	0.0477 (4)
N2	0.89644 (17)	0.66151 (14)	0.96946 (13)	0.0556 (4)
N3	1.02548 (17)	0.65607 (14)	1.03083 (13)	0.0558 (5)
C1	0.62452 (18)	0.86638 (14)	0.90335 (12)	0.0367 (4)
C2	0.49509 (19)	0.87561 (16)	0.84347 (14)	0.0458 (5)
H2	0.4487	0.9414	0.8380	0.055*
C3	0.43489 (19)	0.78866 (17)	0.79221 (14)	0.0496 (5)
H3	0.3487	0.7963	0.7518	0.059*
C4	0.50112 (19)	0.69015 (17)	0.80018 (14)	0.0477 (5)
H4	0.4594	0.6311	0.7662	0.057*
C5	0.62979 (19)	0.68026 (15)	0.85904 (13)	0.0428 (4)
H5	0.6744	0.6138	0.8645	0.051*
C6	0.69472 (16)	0.76729 (14)	0.91056 (12)	0.0355 (4)
C7	0.83541 (17)	0.75244 (15)	0.96944 (13)	0.0401 (4)
C8	0.90722 (18)	0.84518 (16)	1.02506 (14)	0.0473 (5)
H8A	0.9653	0.8820	0.9869	0.057*
H8B	0.9677	0.8183	1.0821	0.057*
C9	1.1295 (2)	0.62777 (15)	0.99497 (15)	0.0497 (5)
C10	1.26558 (19)	0.62074 (14)	1.06248 (13)	0.0428 (4)
C11	1.3907 (2)	0.6245 (2)	1.03087 (17)	0.0634 (6)
H11	1.3910	0.6287	0.9658	0.076*
C12	1.5168 (2)	0.6219 (2)	1.09532 (19)	0.0724 (7)
H12	1.6007	0.6258	1.0731	0.087*
C13	1.5185 (2)	0.61366 (18)	1.19091 (17)	0.0589 (6)
H13	1.6030	0.6108	1.2338	0.071*
C14	1.3945 (2)	0.60965 (17)	1.22303 (15)	0.0534 (5)
H14	1.3951	0.6043	1.2882	0.064*
C15	1.2685 (2)	0.61348 (15)	1.15988 (14)	0.0471 (5)
H15	1.1851	0.6112	1.1828	0.057*
C16	0.6440 (2)	1.06836 (15)	0.92463 (15)	0.0509 (5)
H16A	0.6842	1.1183	0.9745	0.061*
H16B	0.5430	1.0742	0.9159	0.061*
C17	0.6891 (3)	1.0986 (2)	0.83489 (19)	0.0788 (8)
H17A	0.7893	1.0963	0.8440	0.118*
H17B	0.6572	1.1701	0.8170	0.118*
H17C	0.6500	1.0492	0.7854	0.118*
C18	1.1213 (3)	0.6043 (3)	0.89159 (19)	0.0970 (10)
H18A	1.0284	0.5811	0.8643	0.146*
H18B	1.1868	0.5485	0.8844	0.146*
H18C	1.1436	0.6681	0.8596	0.146*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0375 (3)	0.0554 (3)	0.0365 (3)	0.00157 (19)	−0.00216 (19)	−0.0074 (2)
O1	0.0602 (9)	0.0675 (10)	0.0606 (10)	−0.0076 (7)	−0.0063 (8)	−0.0235 (8)
O2	0.0478 (8)	0.0793 (10)	0.0402 (8)	0.0117 (7)	0.0085 (6)	0.0057 (7)
N1	0.0578 (10)	0.0388 (8)	0.0392 (9)	0.0005 (7)	−0.0099 (7)	0.0001 (7)
N2	0.0431 (9)	0.0559 (10)	0.0599 (11)	0.0109 (7)	−0.0106 (8)	0.0007 (9)
N3	0.0418 (9)	0.0636 (11)	0.0548 (11)	0.0136 (8)	−0.0097 (8)	0.0023 (9)
C1	0.0347 (9)	0.0442 (10)	0.0292 (8)	0.0000 (7)	0.0009 (7)	−0.0002 (7)
C2	0.0389 (10)	0.0519 (11)	0.0433 (10)	0.0099 (8)	−0.0009 (8)	0.0002 (9)
C3	0.0335 (9)	0.0670 (13)	0.0425 (11)	0.0018 (8)	−0.0077 (8)	−0.0021 (10)
C4	0.0447 (10)	0.0531 (11)	0.0416 (11)	−0.0072 (8)	−0.0021 (8)	−0.0084 (9)
C5	0.0426 (9)	0.0443 (10)	0.0396 (10)	0.0031 (7)	0.0023 (8)	−0.0025 (8)
C6	0.0307 (8)	0.0441 (10)	0.0300 (8)	0.0010 (7)	0.0014 (6)	0.0022 (7)
C7	0.0332 (9)	0.0498 (10)	0.0358 (9)	0.0016 (7)	0.0027 (7)	0.0014 (8)
C8	0.0306 (9)	0.0653 (12)	0.0437 (11)	0.0009 (8)	0.0010 (8)	−0.0070 (9)
C9	0.0460 (11)	0.0508 (11)	0.0484 (12)	0.0076 (8)	−0.0011 (9)	0.0052 (9)
C10	0.0396 (10)	0.0426 (10)	0.0435 (10)	0.0069 (7)	0.0009 (8)	0.0049 (8)
C11	0.0523 (13)	0.0906 (17)	0.0473 (12)	0.0097 (11)	0.0093 (10)	0.0146 (12)
C12	0.0398 (11)	0.1026 (19)	0.0750 (17)	0.0039 (11)	0.0114 (11)	0.0222 (14)
C13	0.0417 (11)	0.0669 (14)	0.0612 (14)	−0.0007 (9)	−0.0082 (10)	0.0135 (11)
C14	0.0525 (12)	0.0610 (12)	0.0429 (11)	0.0054 (9)	−0.0007 (9)	0.0061 (10)
C15	0.0419 (10)	0.0497 (11)	0.0487 (11)	0.0068 (8)	0.0057 (9)	0.0053 (9)
C16	0.0536 (12)	0.0411 (10)	0.0550 (12)	0.0094 (8)	0.0020 (10)	−0.0072 (9)
C17	0.111 (2)	0.0568 (14)	0.0637 (15)	−0.0098 (14)	0.0021 (15)	0.0094 (12)
C18	0.0702 (17)	0.163 (3)	0.0505 (15)	0.0186 (19)	−0.0083 (13)	−0.0103 (18)

Geometric parameters (Å, º) top

S1—O2	1.4232 (15)	C9—C10	1.487 (3)
S1—O1	1.4264 (15)	C9—C18	1.490 (3)
S1—N1	1.6270 (16)	C10—C11	1.376 (3)
S1—C8	1.7493 (19)	C10—C15	1.387 (3)
N1—C1	1.427 (2)	C11—C12	1.390 (3)
N1—C16	1.477 (2)	C11—H11	0.9300
N2—C7	1.277 (2)	C12—C13	1.364 (3)
N2—N3	1.392 (2)	C12—H12	0.9300
N3—C9	1.266 (3)	C13—C14	1.368 (3)
C1—C2	1.388 (2)	C13—H13	0.9300
C1—C6	1.403 (2)	C14—C15	1.380 (3)
C2—C3	1.373 (3)	C14—H14	0.9300
C2—H2	0.9300	C15—H15	0.9300
C3—C4	1.379 (3)	C16—C17	1.477 (3)
C3—H3	0.9300	C16—H16A	0.9700
C4—C5	1.377 (2)	C16—H16B	0.9700
C4—H4	0.9300	C17—H17A	0.9600
C5—C6	1.392 (3)	C17—H17B	0.9600
C5—H5	0.9300	C17—H17C	0.9600
C6—C7	1.478 (2)	C18—H18A	0.9600
C7—C8	1.497 (3)	C18—H18B	0.9600
C8—H8A	0.9700	C18—H18C	0.9600
C8—H8B	0.9700

O2—S1—O1	118.02 (10)	N3—C9—C18	123.7 (2)
O2—S1—N1	111.22 (9)	C10—C9—C18	120.4 (2)
O1—S1—N1	107.84 (9)	C11—C10—C15	118.41 (18)
O2—S1—C8	107.66 (9)	C11—C10—C9	121.41 (19)
O1—S1—C8	109.90 (9)	C15—C10—C9	120.15 (18)
N1—S1—C8	100.84 (9)	C10—C11—C12	120.6 (2)
C1—N1—C16	121.41 (15)	C10—C11—H11	119.7
C1—N1—S1	117.52 (12)	C12—C11—H11	119.7
C16—N1—S1	120.46 (13)	C13—C12—C11	120.5 (2)
C7—N2—N3	114.08 (16)	C13—C12—H12	119.7
C9—N3—N2	117.05 (18)	C11—C12—H12	119.7
C2—C1—C6	119.40 (16)	C12—C13—C14	119.3 (2)
C2—C1—N1	119.94 (16)	C12—C13—H13	120.3
C6—C1—N1	120.64 (15)	C14—C13—H13	120.3
C3—C2—C1	120.69 (17)	C13—C14—C15	120.7 (2)
C3—C2—H2	119.7	C13—C14—H14	119.6
C1—C2—H2	119.7	C15—C14—H14	119.6
C2—C3—C4	120.59 (17)	C14—C15—C10	120.42 (19)
C2—C3—H3	119.7	C14—C15—H15	119.8
C4—C3—H3	119.7	C10—C15—H15	119.8
C5—C4—C3	119.17 (17)	N1—C16—C17	112.46 (18)
C5—C4—H4	120.4	N1—C16—H16A	109.1
C3—C4—H4	120.4	C17—C16—H16A	109.1
C4—C5—C6	121.62 (17)	N1—C16—H16B	109.1
C4—C5—H5	119.2	C17—C16—H16B	109.1
C6—C5—H5	119.2	H16A—C16—H16B	107.8
C5—C6—C1	118.50 (15)	C16—C17—H17A	109.5
C5—C6—C7	118.95 (15)	C16—C17—H17B	109.5
C1—C6—C7	122.54 (15)	H17A—C17—H17B	109.5
N2—C7—C6	119.48 (16)	C16—C17—H17C	109.5
N2—C7—C8	120.71 (16)	H17A—C17—H17C	109.5
C6—C7—C8	119.76 (15)	H17B—C17—H17C	109.5
C7—C8—S1	111.91 (12)	C9—C18—H18A	109.5
C7—C8—H8A	109.2	C9—C18—H18B	109.5
S1—C8—H8A	109.2	H18A—C18—H18B	109.5
C7—C8—H8B	109.2	C9—C18—H18C	109.5
S1—C8—H8B	109.2	H18A—C18—H18C	109.5
H8A—C8—H8B	107.9	H18B—C18—H18C	109.5
N3—C9—C10	115.90 (18)

O2—S1—N1—C1	−59.42 (16)	C1—C6—C7—N2	−176.73 (18)
O1—S1—N1—C1	169.72 (14)	C5—C6—C7—C8	179.76 (17)
C8—S1—N1—C1	54.52 (16)	C1—C6—C7—C8	0.7 (3)
O2—S1—N1—C16	111.72 (17)	N2—C7—C8—S1	−153.81 (16)
O1—S1—N1—C16	−19.14 (19)	C6—C7—C8—S1	28.8 (2)
C8—S1—N1—C16	−134.34 (16)	O2—S1—C8—C7	64.98 (16)
C7—N2—N3—C9	−125.1 (2)	O1—S1—C8—C7	−165.27 (14)
C16—N1—C1—C2	−21.2 (3)	N1—S1—C8—C7	−51.62 (16)
S1—N1—C1—C2	149.88 (15)	N2—N3—C9—C10	−178.94 (16)
C16—N1—C1—C6	157.43 (18)	N2—N3—C9—C18	2.2 (3)
S1—N1—C1—C6	−31.5 (2)	N3—C9—C10—C11	−159.4 (2)
C6—C1—C2—C3	0.7 (3)	C18—C9—C10—C11	19.5 (3)
N1—C1—C2—C3	179.27 (18)	N3—C9—C10—C15	18.7 (3)
C1—C2—C3—C4	0.8 (3)	C18—C9—C10—C15	−162.4 (2)
C2—C3—C4—C5	−1.1 (3)	C15—C10—C11—C12	−0.5 (3)
C3—C4—C5—C6	−0.1 (3)	C9—C10—C11—C12	177.6 (2)
C4—C5—C6—C1	1.5 (3)	C10—C11—C12—C13	1.2 (4)
C4—C5—C6—C7	−177.54 (17)	C11—C12—C13—C14	−1.0 (4)
C2—C1—C6—C5	−1.8 (3)	C12—C13—C14—C15	0.2 (3)
N1—C1—C6—C5	179.60 (17)	C13—C14—C15—C10	0.4 (3)
C2—C1—C6—C7	177.25 (16)	C11—C10—C15—C14	−0.3 (3)
N1—C1—C6—C7	−1.4 (3)	C9—C10—C15—C14	−178.37 (18)
N3—N2—C7—C6	−177.29 (16)	C1—N1—C16—C17	−69.1 (3)
N3—N2—C7—C8	5.3 (3)	S1—N1—C16—C17	120.06 (19)
C5—C6—C7—N2	2.3 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8A···O1ⁱ	0.97	2.43	3.390 (2)	170
C16—H16B···O2ⁱⁱ	0.97	2.52	3.481 (2)	171

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

Experimental details

Crystal data
Chemical formula	C₁₈H₁₉N₃O₂S
M_r	341.42
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	296
a, b, c (Å)	9.7278 (3), 12.4327 (3), 14.2607 (4)
β (°)	100.725 (1)
V (Å³)	1694.60 (8)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.21
Crystal size (mm)	0.41 × 0.08 × 0.06

Data collection
Diffractometer	Bruker Kappa APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2007)
T_min, T_max	0.920, 0.988
No. of measured, independent and observed [I > 2σ(I)] reflections	16049, 4129, 2887
R_int	0.035
(sin θ/λ)_max (Å⁻¹)	0.667

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.151, 1.00
No. of reflections	4127
No. of parameters	219
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.28, −0.32

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8A···O1ⁱ	0.97	2.43	3.390 (2)	170
C16—H16B···O2ⁱⁱ	0.97	2.52	3.481 (2)	171

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

Acknowledgements

MS acknowledges the Higher Education Commission of Pakistan for supporting PhD studies and for the provision of a grant to strengthen the Materials Chemistry Laboratory at GC University Lahore, Pakistan.

References

Bruker (2007). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354–1358. CrossRef CAS Web of Science Google Scholar
Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838. CrossRef CAS IUCr Journals Google Scholar
Shafiq, M., Khan, I. U., Zia-ur-Rehman, M., Arshad, M. N. & Asiri, A. M. (2011a). Acta Cryst. E67, o2038. Web of Science CSD CrossRef IUCr Journals Google Scholar
Shafiq, M., Khan, I. U., Zia-ur-Rehman, M., Arshad, M. N. & Asiri, A. M. (2011b). Acta Cryst. E67, o2092. Web of Science CSD CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.