2-Bromo-N-(dibenzyl­carbamothioyl)benzamide

Nasir, M.F.M.; Hassan, I.N.; Wan Daud, W.R.; Yamin, B.M.; Kassim, M.B.

doi:10.1107/S1600536811014711

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 67| Part 5| May 2011| Page o1218

doi:10.1107/S1600536811014711

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2-Bromo-N-(dibenzylcarbamothioyl)benzamide

Mohd Faizal Md Nasir,^a Ibrahim N. Hassan,^a ^* Wan Ramli Wan Daud,^b,^a Bohari M. Yamin ^c and Mohammad B. Kassim ^c,^a

^aFuel Cell Institute, Universiti Kebangsaan Malaysia, UKM 43600 Bangi Selangor, Malaysia, ^bDepartment of Chemical and Process Engineering, Faculty of Engineering, Universiti Kebangsaan Malaysia, UKM 43600 Bangi Selangor, Malaysia, and ^cSchool of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, UKM 43600 Bangi Selangor, Malaysia
^*Correspondence e-mail: ibnhum@gmail.com

(Received 14 April 2011; accepted 19 April 2011; online 29 April 2011)

The 2-bromobenzoyl group in the title compound, C₂₂H₁₉BrN₂OS, adopts an E conformation with respect to the thiono S atom across the N—C bond. In the crystal structure, the molecule is stablized by N—H⋯O intermolecular hydrogen bonds, forming a one-dimensional chain along the b axis.

Related literature

For related structures, see: Yamin & Hassan (2004 ); Hassan et al. (2008a ,b ,c , 2009 ). For the synthesis, see: Hassan et al. (2008a). For reference bond distances, see: Allen et al. (2004 ).

Experimental

Crystal data

C₂₂H₁₉BrN₂OS
M_r = 439.36
Tetragonal, P 4₃
a = 12.2833 (16) Å
c = 14.002 (4) Å
V = 2112.6 (7) Å³
Z = 4
Mo Kα radiation
μ = 2.06 mm⁻¹
T = 273 K
0.35 × 0.31 × 0.23 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2000 ) T_min = 0.533, T_max = 0.649
15683 measured reflections
5217 independent reflections
2506 reflections with I > 2σ(I)
R_int = 0.064

Refinement

R[F² > 2σ(F²)] = 0.050
wR(F²) = 0.118
S = 0.93
5217 reflections
244 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.57 e Å⁻³
Δρ_min = −0.20 e Å⁻³
Absolute structure: Flack (1983 ), with 2474 Friedel pairs
Flack parameter: −0.001 (11)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯Br1	0.86	2.79	3.220 (3)	113
N1—H1A⋯O1ⁱ	0.86	2.20	2.903 (4)	139
Symmetry code: (i) $[-y+1, x, z-{\script{1\over 4}}]$ .

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 ), ORTEP-3 for Windows (Farrugia, 1997 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXTL (Sheldrick, 2008), PARST (Nardelli, 1995 ) and PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811014711/dn2677sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811014711/dn2677Isup2.hkl

checkCIF report

Comment top

The title compound, I, is a thiourea derivative of dibenzylamine analogous to our previous reported, ethyl-2-(3-benzoylthioureido)acetate (Hassan et al., 2008a), propyl-2-(3-benzoylthioureido)acetate (Hassan et al., 2008b), butyl-2-(3-benzoylthioureido)acetate (Hassan et al., 2008c) and 1-(2-morpholinoethyl)-3-(3-phenylacryloyl)thiourea (Yamin & Hassan, 2004). The molecule has the 2-bromobenzoyl group adopting an E conformation, with respect to the thiono S atom across the N1—C8 bond, whereas both the phenyl ring of the dibenzylamine group adopt E and Z conformation relative to the S atom across the N2—C8 bond (Fig. 1). The phenyl ring, (C1–C6), and the thiourea fragment, (S1/N1/N2/C8), are essentially planar and the dihedral angle between them is 72.9 (2)°. The bond lengths and angles in the molecules are in normal ranges (Allen et al., 1987).

Both phenyl rings, [C10/C11/C12/C13/C14/C15] and [C17/C18/C19/C20/C21/C22] are essentially planar and they are twisted to each other by a dihedral angle of 22.4 (4)°. There is weak intramolecular hydrogen bond, N1—H1A···Br1 (Table 1). As a result, one pseudo-six-membered ring (N1/H1A/Br1/C1/C6/C7) is formed. The intermolecular N1—H1A···O1 hydrogen bonds (Table 1,) links the molecules into a chain parallel to the b axis (Fig. 2).

Related literature top

For related structures, see: Yamin & Hassan (2004); Hassan et al. (2008a,b,c, 2009). For synthesis, see: Hassan et al. (2008a). For reference bond distances, see: Allen et al. (1987).

Experimental top

The title compound was synthesized according to a previously reported compound (Hassan et al., 2008a). A colourless crystal, suitable for X-ray crystallography, was obtained by a slow evaporation from methanolic solution at room temperature (yield 83%).

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008), PARST (Nardelli, 1995) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of (I), with the atoms labeling scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are represented as small spheres of arbitrary radii.
	Fig. 2. Partial packing view of (I) showing the formation of the chain through N—H···O hydrogen bondings. H bonds are shown as dashed lines. [Symmetry code: (i) -y + 1, x, z - 1/4]

2-Bromo-N-(dibenzylcarbamothioyl)benzamide top

Crystal data top

C₂₂H₁₉BrN₂OS	D_x = 1.381 Mg m⁻³
M_r = 439.36	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, P4₃	Cell parameters from 2531 reflections
Hall symbol: P 4cw	θ = 1.7–28.4°
a = 12.2833 (16) Å	µ = 2.06 mm⁻¹
c = 14.002 (4) Å	T = 273 K
V = 2112.6 (7) Å³	Block, colourless
Z = 4	0.35 × 0.31 × 0.23 mm
F(000) = 896

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	5217 independent reflections
Radiation source: fine-focus sealed tube	2506 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.064
ω scans	θ_max = 28.4°, θ_min = 1.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 2000)	h = −12→16
T_min = 0.533, T_max = 0.649	k = −14→16
15683 measured reflections	l = −18→18

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.050	H-atom parameters constrained
wR(F²) = 0.118	w = 1/[σ²(F_o²) + (0.0418P)²] where P = (F_o² + 2F_c²)/3
S = 0.93	(Δ/σ)_max < 0.001
5217 reflections	Δρ_max = 0.57 e Å⁻³
244 parameters	Δρ_min = −0.20 e Å⁻³
1 restraint	Absolute structure: Flack (1983), with 2474 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.001 (11)

Crystal data top

C₂₂H₁₉BrN₂OS	Z = 4
M_r = 439.36	Mo Kα radiation
Tetragonal, P4₃	µ = 2.06 mm⁻¹
a = 12.2833 (16) Å	T = 273 K
c = 14.002 (4) Å	0.35 × 0.31 × 0.23 mm
V = 2112.6 (7) Å³

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	5217 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2000)	2506 reflections with I > 2σ(I)
T_min = 0.533, T_max = 0.649	R_int = 0.064
15683 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.050	H-atom parameters constrained
wR(F²) = 0.118	Δρ_max = 0.57 e Å⁻³
S = 0.93	Δρ_min = −0.20 e Å⁻³
5217 reflections	Absolute structure: Flack (1983), with 2474 Friedel pairs
244 parameters	Absolute structure parameter: −0.001 (11)
1 restraint

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 > 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
Br1	0.20156 (4)	0.59332 (4)	0.23207 (5)	0.0975 (2)
S1	0.48743 (15)	0.81061 (10)	−0.01270 (10)	0.1136 (5)
O1	0.5373 (2)	0.6765 (2)	0.2480 (2)	0.0656 (7)
N1	0.4138 (2)	0.6950 (2)	0.1306 (2)	0.0552 (8)
H1A	0.3584	0.6663	0.1027	0.066*
N2	0.4512 (3)	0.8761 (3)	0.1662 (2)	0.0642 (9)
C1	0.3189 (3)	0.4915 (3)	0.2306 (3)	0.0685 (11)
C2	0.2938 (5)	0.3838 (5)	0.2467 (4)	0.0973 (16)
H2A	0.2218	0.3628	0.2562	0.117*
C3	0.3751 (6)	0.3079 (4)	0.2485 (4)	0.1067 (18)
H3A	0.3579	0.2349	0.2578	0.128*
C4	0.4787 (5)	0.3375 (4)	0.2371 (5)	0.0959 (15)
H4A	0.5333	0.2851	0.2400	0.115*
C5	0.5061 (4)	0.4451 (3)	0.2210 (3)	0.0684 (11)
H5A	0.5786	0.4647	0.2126	0.082*
C6	0.4249 (3)	0.5240 (3)	0.2174 (3)	0.0567 (10)
C7	0.4632 (3)	0.6395 (3)	0.2022 (3)	0.0517 (10)
C8	0.4501 (4)	0.7972 (3)	0.1011 (3)	0.0638 (11)
C9	0.3979 (4)	0.8690 (3)	0.2597 (3)	0.0694 (12)
H9A	0.4523	0.8763	0.3095	0.083*
H9B	0.3645	0.7979	0.2663	0.083*
C10	0.3114 (4)	0.9563 (4)	0.2731 (4)	0.0733 (13)
C11	0.2355 (5)	0.9757 (5)	0.2031 (5)	0.120 (2)
H11A	0.2383	0.9383	0.1454	0.144*
C12	0.1542 (6)	1.0525 (7)	0.2202 (8)	0.156 (3)
H12A	0.1035	1.0672	0.1726	0.187*
C13	0.1477 (6)	1.1055 (6)	0.3037 (9)	0.137 (3)
H13A	0.0923	1.1556	0.3145	0.164*
C14	0.2215 (7)	1.0855 (5)	0.3709 (6)	0.116 (2)
H14A	0.2171	1.1222	0.4289	0.139*
C15	0.3049 (5)	1.0111 (4)	0.3565 (4)	0.0841 (14)
H15A	0.3562	0.9991	0.4041	0.101*
C16	0.5113 (4)	0.9773 (3)	0.1497 (4)	0.0799 (13)
H16A	0.4655	1.0387	0.1664	0.096*
H16B	0.5292	0.9831	0.0824	0.096*
C17	0.6145 (4)	0.9818 (3)	0.2075 (4)	0.0722 (13)
C18	0.6297 (6)	1.0599 (5)	0.2746 (5)	0.117 (2)
H18A	0.5758	1.1119	0.2839	0.140*
C19	0.7213 (7)	1.0642 (6)	0.3286 (7)	0.161 (4)
H19A	0.7279	1.1164	0.3763	0.193*
C20	0.8018 (6)	0.9934 (7)	0.3131 (6)	0.134 (3)
H20A	0.8672	1.0007	0.3459	0.160*
C21	0.7890 (5)	0.9132 (6)	0.2515 (7)	0.132 (3)
H21A	0.8432	0.8609	0.2443	0.158*
C22	0.6946 (5)	0.9072 (5)	0.1976 (4)	0.1103 (19)
H22A	0.6861	0.8508	0.1539	0.132*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0739 (3)	0.1215 (4)	0.0970 (4)	−0.0048 (3)	0.0148 (3)	0.0028 (4)
S1	0.1990 (16)	0.0888 (8)	0.0531 (7)	−0.0186 (9)	0.0167 (10)	0.0149 (8)
O1	0.0769 (17)	0.0579 (16)	0.0620 (19)	−0.0059 (14)	−0.0219 (16)	0.0042 (14)
N1	0.064 (2)	0.056 (2)	0.0457 (18)	−0.0031 (16)	−0.0102 (15)	0.0076 (14)
N2	0.082 (2)	0.050 (2)	0.061 (2)	0.0049 (18)	−0.0021 (18)	0.0128 (18)
C1	0.083 (3)	0.072 (3)	0.051 (2)	−0.016 (2)	0.003 (3)	0.007 (2)
C2	0.108 (4)	0.097 (4)	0.087 (4)	−0.042 (4)	0.011 (3)	0.011 (3)
C3	0.156 (6)	0.066 (3)	0.098 (4)	−0.026 (4)	−0.007 (4)	0.014 (3)
C4	0.134 (5)	0.063 (3)	0.090 (4)	0.012 (3)	−0.004 (4)	0.019 (3)
C5	0.092 (3)	0.057 (2)	0.056 (3)	0.000 (2)	−0.005 (2)	0.013 (2)
C6	0.075 (3)	0.055 (2)	0.041 (2)	−0.009 (2)	−0.0036 (19)	0.0091 (18)
C7	0.060 (2)	0.056 (2)	0.039 (2)	0.007 (2)	−0.0019 (18)	0.0025 (17)
C8	0.079 (3)	0.054 (3)	0.058 (3)	0.001 (2)	−0.009 (2)	0.013 (2)
C9	0.076 (3)	0.065 (3)	0.067 (3)	0.006 (2)	−0.003 (2)	0.004 (2)
C10	0.070 (3)	0.056 (3)	0.094 (4)	0.001 (2)	−0.003 (3)	−0.004 (2)
C11	0.110 (4)	0.113 (4)	0.135 (6)	0.034 (4)	−0.056 (4)	−0.034 (4)
C12	0.117 (5)	0.139 (6)	0.212 (10)	0.046 (5)	−0.072 (6)	−0.031 (7)
C13	0.082 (5)	0.090 (5)	0.237 (10)	0.007 (4)	0.039 (6)	−0.006 (6)
C14	0.143 (6)	0.065 (4)	0.140 (6)	−0.003 (4)	0.042 (5)	−0.017 (4)
C15	0.099 (4)	0.058 (3)	0.095 (4)	−0.002 (3)	0.009 (3)	−0.009 (3)
C16	0.109 (4)	0.049 (3)	0.082 (3)	−0.004 (3)	0.005 (3)	0.013 (2)
C17	0.080 (3)	0.048 (2)	0.089 (4)	0.000 (2)	0.011 (3)	−0.002 (2)
C18	0.129 (5)	0.079 (4)	0.143 (5)	0.021 (4)	−0.033 (4)	−0.041 (4)
C19	0.125 (6)	0.128 (5)	0.229 (10)	0.021 (5)	−0.057 (6)	−0.094 (6)
C20	0.095 (5)	0.148 (6)	0.159 (7)	−0.013 (5)	−0.022 (4)	−0.042 (5)
C21	0.087 (4)	0.143 (6)	0.166 (7)	0.027 (4)	0.004 (5)	−0.039 (6)
C22	0.105 (4)	0.110 (4)	0.116 (5)	0.013 (4)	0.007 (4)	−0.041 (3)

Geometric parameters (Å, º) top

Br1—C1	1.909 (4)	C10—C11	1.372 (7)
S1—C8	1.666 (4)	C11—C12	1.394 (10)
O1—C7	1.203 (4)	C11—H11A	0.9300
N1—C7	1.356 (5)	C12—C13	1.341 (11)
N1—C8	1.396 (5)	C12—H12A	0.9300
N1—H1A	0.8602	C13—C14	1.329 (11)
N2—C8	1.330 (5)	C13—H13A	0.9300
N2—C16	1.464 (6)	C14—C15	1.388 (8)
N2—C9	1.467 (5)	C14—H14A	0.9300
C1—C6	1.375 (5)	C15—H15A	0.9300
C1—C2	1.376 (6)	C16—C17	1.505 (7)
C2—C3	1.367 (8)	C16—H16A	0.9700
C2—H2A	0.9300	C16—H16B	0.9700
C3—C4	1.334 (8)	C17—C22	1.352 (7)
C3—H3A	0.9300	C17—C18	1.355 (7)
C4—C5	1.382 (6)	C18—C19	1.356 (9)
C4—H4A	0.9300	C18—H18A	0.9300
C5—C6	1.392 (5)	C19—C20	1.334 (9)
C5—H5A	0.9300	C19—H19A	0.9300
C6—C7	1.509 (5)	C20—C21	1.319 (10)
C9—C10	1.521 (6)	C20—H20A	0.9300
C9—H9A	0.9700	C21—C22	1.386 (9)
C9—H9B	0.9700	C21—H21A	0.9300
C10—C15	1.350 (7)	C22—H22A	0.9300

C7—N1—C8	121.9 (3)	C10—C11—C12	118.7 (6)
C7—N1—H1A	119.0	C10—C11—H11A	120.6
C8—N1—H1A	119.2	C12—C11—H11A	120.6
C8—N2—C16	121.0 (4)	C13—C12—C11	121.4 (7)
C8—N2—C9	124.3 (3)	C13—C12—H12A	119.3
C16—N2—C9	114.6 (4)	C11—C12—H12A	119.3
C6—C1—C2	120.9 (4)	C14—C13—C12	119.1 (7)
C6—C1—Br1	121.7 (3)	C14—C13—H13A	120.4
C2—C1—Br1	117.3 (4)	C12—C13—H13A	120.4
C3—C2—C1	119.7 (5)	C13—C14—C15	121.4 (7)
C3—C2—H2A	120.2	C13—C14—H14A	119.3
C1—C2—H2A	120.2	C15—C14—H14A	119.3
C4—C3—C2	120.6 (5)	C10—C15—C14	119.9 (6)
C4—C3—H3A	119.7	C10—C15—H15A	120.1
C2—C3—H3A	119.7	C14—C15—H15A	120.1
C3—C4—C5	120.8 (5)	N2—C16—C17	111.8 (4)
C3—C4—H4A	119.6	N2—C16—H16A	109.3
C5—C4—H4A	119.6	C17—C16—H16A	109.3
C4—C5—C6	119.9 (5)	N2—C16—H16B	109.3
C4—C5—H5A	120.1	C17—C16—H16B	109.3
C6—C5—H5A	120.1	H16A—C16—H16B	107.9
C1—C6—C5	118.1 (4)	C22—C17—C18	116.8 (5)
C1—C6—C7	126.0 (4)	C22—C17—C16	122.2 (5)
C5—C6—C7	115.9 (4)	C18—C17—C16	121.0 (5)
O1—C7—N1	122.9 (3)	C17—C18—C19	121.9 (6)
O1—C7—C6	121.1 (3)	C17—C18—H18A	119.1
N1—C7—C6	115.9 (3)	C19—C18—H18A	119.1
N2—C8—N1	117.1 (3)	C20—C19—C18	119.9 (7)
N2—C8—S1	125.5 (3)	C20—C19—H19A	120.0
N1—C8—S1	117.4 (3)	C18—C19—H19A	120.0
N2—C9—C10	112.3 (4)	C21—C20—C19	120.3 (7)
N2—C9—H9A	109.1	C21—C20—H20A	119.8
C10—C9—H9A	109.1	C19—C20—H20A	119.8
N2—C9—H9B	109.1	C20—C21—C22	119.7 (6)
C10—C9—H9B	109.1	C20—C21—H21A	120.2
H9A—C9—H9B	107.9	C22—C21—H21A	120.2
C15—C10—C11	119.4 (5)	C17—C22—C21	121.1 (5)
C15—C10—C9	119.9 (5)	C17—C22—H22A	119.4
C11—C10—C9	120.6 (5)	C21—C22—H22A	119.4

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···Br1	0.86	2.79	3.220 (3)	113
N1—H1A···O1ⁱ	0.86	2.20	2.903 (4)	139

Symmetry code: (i) −y+1, x, z−1/4.

Experimental details

Crystal data
Chemical formula	C₂₂H₁₉BrN₂OS
M_r	439.36
Crystal system, space group	Tetragonal, P4₃
Temperature (K)	273
a, c (Å)	12.2833 (16), 14.002 (4)
V (Å³)	2112.6 (7)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	2.06
Crystal size (mm)	0.35 × 0.31 × 0.23

Data collection
Diffractometer	Bruker SMART APEX CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2000)
T_min, T_max	0.533, 0.649
No. of measured, independent and observed [I > 2σ(I)] reflections	15683, 5217, 2506
R_int	0.064
(sin θ/λ)_max (Å⁻¹)	0.668

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.050, 0.118, 0.93
No. of reflections	5217
No. of parameters	244
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.57, −0.20
Absolute structure	Flack (1983), with 2474 Friedel pairs
Absolute structure parameter	−0.001 (11)

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), SHELXTL (Sheldrick, 2008), PARST (Nardelli, 1995) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···Br1	0.86	2.79	3.220 (3)	112.5
N1—H1A···O1ⁱ	0.86	2.20	2.903 (4)	138.7

Symmetry code: (i) −y+1, x, z−1/4.

Acknowledgements

The authors thank the Universiti Kebangsaan Malaysia for providing facilities and grants (postdoctoral for INH, grant Nos. UKM-GUP-BTT-07-30-190 and UKM-OUP-TK-16-73/2010), and the Kementerian Pengajian Tinggi, Malaysia, for research fund No. UKM-AP-TK-05-2009.

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