(E)-1-(2,5-Dichloro­thio­phen-3-yl)ethan­one [8-(trifluoro­meth­yl)quinolin-4-yl]hydrazone

Dayananda, A.S.; Yathirajan, H.S.; Harrison, W.T.A.; Slawin, A.M.Z.

doi:10.1107/S1600536812005673

organic compounds

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ISSN: 2056-9890

Volume 68| Part 3| March 2012| Page o790

doi:10.1107/S1600536812005673

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(E)-1-(2,5-Dichlorothiophen-3-yl)ethanone [8-(trifluoromethyl)quinolin-4-yl]hydrazone

A. S. Dayananda,^a H. S. Yathirajan,^a ^* William T. A. Harrison ^b and Alexandra M. Z. Slawin ^c

^aDepartment of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India, ^bDepartment of Chemistry, University of Aberdeen, Aberdeen AB24 3UE, Scotland, and ^cSchool of Chemistry, University of St Andrews, St Andrews KY16 9ST, Scotland
^*Correspondence e-mail: yathirajan@hotmail.com

(Received 17 January 2012; accepted 8 February 2012; online 24 February 2012)

In the title compound, C₁₆H₁₀Cl₂F₃N₃S, the dihedral angle between the quinoline and thiophene ring systems is 4.94 (10)°. The NH group of the hydrazone moiety does not form a hydrogen bond, due to a steric crowding. In the crystal, the thiophene ring takes part in weak π–π stacking interactions with the pyridine ring [centroid-to-centroid separation = 3.7553 (19) Å and interplanar angle = 5.48 (12)°] and the benzene ring [3.7927 (19) Å and 4.58 (12)°]. Together, these lead to [100] stacks of molecules in an alternating head-to-tail arrangement, with two π–π stacking contacts between each adjacent pair.

Related literature

For related structures derived from 4-hydrazinyl-8-(trifluoromethyl)quinoline and background to Schiff bases, see; Jasinski et al. (2010 ); Dutkiewicz et al. (2010 ).

Experimental

Crystal data

C₁₆H₁₀Cl₂F₃N₃S
M_r = 404.23
Monoclinic, P 2₁ /c
a = 7.687 (2) Å
b = 14.392 (5) Å
c = 14.360 (5) Å
β = 95.053 (9)°
V = 1582.5 (9) Å³
Z = 4
Mo Kα radiation
μ = 0.58 mm⁻¹
T = 73 K
0.10 × 0.10 × 0.10 mm

Data collection

Rigaku Mercury CCD diffractometer
9805 measured reflections
2897 independent reflections
2369 reflections with I > 2σ(I)
R_int = 0.082

Refinement

R[F² > 2σ(F²)] = 0.049
wR(F²) = 0.128
S = 1.06
2897 reflections
231 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.35 e Å⁻³
Δρ_min = −0.37 e Å⁻³

Data collection: CrystalClear (Rigaku, 2009 ); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812005673/kp2384sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812005673/kp2384Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812005673/kp2384Isup3.cml

checkCIF report

Comment top

As a part of our ongoing studies of Schiff bases derived from 4-hydrazinyl-8-(trifluoromethyl)quinoline (Jasinski et al., 2010; Dutkiewicz et al., 2010), we now describe the synthesis and structure of the title compound, (I), (Fig. 1).

The quinoline ring system (C1–C9,N1) in (I) is almost planar (r.m.s. deviation = 0.026 Å). It subtends a dihedral angle of 4.94 (10)° with respect to the thiophene ring (C12–C15,S1). One F atom of the trifluoromethane group lies close to the quinoline plane [deviation = -0.098 (2) Å], whereas the other two F atoms are displaced by 1.034 (1) and -1.109 (2) Å. The two Cl atoms bonded to the thiophene ring are slightly displaced from the ring plane by almost the same magnitude but in opposite direction [-0.050 (1) Å for Cl1 and 0.045 (1) Å for Cl2].

In the crystal, the NH group does not form a hydrogen bond, as it seems to be sterically blocked by H5 and the C11 methyl group. π-π Stacking between the thiophene ring and the pyridine ring [(with symmetry operation -x, 1 - y, 1 - z), and centroid–centroid separation = 3.7553 (19) Å; interplanar angle = 5.48 (12)°] and also to a benzene ring [symmetry operated (1 - x, 1 - y, 1 - z) and centroid–centroid separation of 3.7927 (19) Å and interplanar angle of 4.58 (12)°] leads to [100] stacking of the molecules in an alternating head to tail arrangement. Each adjacent pair of molecules is linked by two π–π stacking interactions (Fig. 2).

Related literature top

For related structures derived from 4-hydrazinyl-8-(trifluoromethyl)quinoline and background to Schiff bases, see; Jasinski et al. (2010); Dutkiewicz et al. (2010).

Experimental top

A solution of 4-hydrazino-8-(trifluoromethyl)quinoline (2.2 g, 10 mmol) and 2,5-dichloro-3-acetylthiophene (1.99 g, 10.2 mmol) in 10 ml of ethanol was refluxed for 24 h under a nitrogen atmosphere in a dark. Then, the reaction mass was cooled and the solid separated by filtration. Colourless prisms of (I) were obtained by slow evaporation of an ethyl acetate solution (m.p. 465–467 K). Anal. Calcd. for C₁₆H₁₀Cl₂F₃N₃S: C 47.54; H 2.49; N 10.39; S 7.93%; Found: C 47.51; H 2.48; N 10.36; S 7.91%.

Computing details top

Data collection: CrystalClear (Rigaku, 2009); cell refinement: CrystalClear (Rigaku, 2009); data reduction: CrystalClear (Rigaku, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of (I) showing 30% probability displacement ellipsoids for non-H atoms.
	Fig. 2. Part of a [100] chain of molecules linked by aromatic π–π stacking interactions. Symmetry codes: (i) -x, 1 - y, 1 - z; (ii) 1 - x, 1 - y, 1 - z.

(E)-1-(2,5-Dichlorothiophen-3-yl)ethanone [8-(trifluoromethyl)quinolin-4-yl]hydrazone top

Crystal data top

C₁₆H₁₀Cl₂F₃N₃S	F(000) = 816
M_r = 404.23	D_x = 1.697 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 4944 reflections
a = 7.687 (2) Å	θ = 2.0–28.5°
b = 14.392 (5) Å	µ = 0.58 mm⁻¹
c = 14.360 (5) Å	T = 73 K
β = 95.053 (9)°	Prism, colourless
V = 1582.5 (9) Å³	0.10 × 0.10 × 0.10 mm
Z = 4

Data collection top

Rigaku Mercury CCD diffractometer	2369 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.082
Graphite monochromator	θ_max = 25.4°, θ_min = 2.0°
ω scans	h = −8→9
9805 measured reflections	k = −17→13
2897 independent reflections	l = −17→16

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)] = 0.049	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.128	w = 1/[σ²(F_o²) + (0.0544P)² + 0.0123P] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max < 0.001
2897 reflections	Δρ_max = 0.35 e Å⁻³
231 parameters	Δρ_min = −0.37 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008)
Primary atom site location: structure-invariant direct methods

Crystal data top

C₁₆H₁₀Cl₂F₃N₃S	V = 1582.5 (9) Å³
M_r = 404.23	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 7.687 (2) Å	µ = 0.58 mm⁻¹
b = 14.392 (5) Å	T = 73 K
c = 14.360 (5) Å	0.10 × 0.10 × 0.10 mm
β = 95.053 (9)°

Data collection top

Rigaku Mercury CCD diffractometer	2369 reflections with I > 2σ(I)
9805 measured reflections	R_int = 0.082
2897 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.049	0 restraints
wR(F²) = 0.128	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	Δρ_max = 0.35 e Å⁻³
2897 reflections	Δρ_min = −0.37 e Å⁻³
231 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
C1	0.4410 (3)	0.25700 (19)	0.39915 (18)	0.0193 (6)
C2	0.5208 (3)	0.16942 (18)	0.42084 (19)	0.0196 (6)
C3	0.5718 (3)	0.1444 (2)	0.51114 (19)	0.0233 (6)
H3	0.6244	0.0855	0.5241	0.028*
C4	0.5458 (3)	0.20637 (19)	0.58497 (19)	0.0222 (6)
H4	0.5840	0.1896	0.6474	0.027*
C5	0.4662 (3)	0.29017 (19)	0.56742 (18)	0.0212 (6)
H5	0.4475	0.3304	0.6180	0.025*
C6	0.4113 (3)	0.31781 (19)	0.47515 (19)	0.0184 (6)
C7	0.3276 (3)	0.40483 (18)	0.45162 (18)	0.0185 (6)
C8	0.2886 (3)	0.4263 (2)	0.35855 (19)	0.0227 (6)
H8	0.2367	0.4842	0.3407	0.027*
C9	0.3269 (3)	0.3612 (2)	0.29090 (19)	0.0213 (6)
H9	0.2985	0.3779	0.2274	0.026*
C10	0.1600 (3)	0.59983 (19)	0.56281 (18)	0.0187 (6)
C11	0.1918 (3)	0.5794 (2)	0.66590 (19)	0.0241 (6)
H11A	0.1622	0.5145	0.6775	0.036*
H11B	0.1188	0.6203	0.7007	0.036*
H11C	0.3151	0.5902	0.6864	0.036*
C12	0.0773 (3)	0.68922 (19)	0.53327 (18)	0.0181 (6)
C13	0.0493 (3)	0.76274 (19)	0.59770 (19)	0.0210 (6)
H13	0.0760	0.7573	0.6633	0.025*
C14	−0.0183 (3)	0.83985 (18)	0.55647 (19)	0.0203 (6)
C15	0.0230 (3)	0.71698 (18)	0.44394 (18)	0.0201 (6)
C16	0.5511 (3)	0.1035 (2)	0.3424 (2)	0.0260 (7)
N1	0.3989 (3)	0.27860 (16)	0.30701 (15)	0.0210 (5)
N2	0.2884 (3)	0.46492 (16)	0.52193 (17)	0.0218 (5)
H1	0.310 (3)	0.449 (2)	0.578 (2)	0.026*
N3	0.2058 (3)	0.54653 (15)	0.49702 (15)	0.0205 (5)
F1	0.65951 (18)	0.13668 (11)	0.28208 (10)	0.0273 (4)
F2	0.6221 (2)	0.02239 (12)	0.37478 (12)	0.0380 (5)
F3	0.40389 (19)	0.07936 (12)	0.28996 (12)	0.0349 (5)
S1	−0.05583 (8)	0.82904 (5)	0.43743 (5)	0.0231 (2)
Cl1	0.01844 (9)	0.65772 (5)	0.34012 (5)	0.0280 (2)
Cl2	−0.06338 (9)	0.94308 (5)	0.60984 (5)	0.0289 (2)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0184 (12)	0.0234 (16)	0.0161 (14)	−0.0038 (11)	0.0015 (10)	−0.0023 (12)
C2	0.0190 (12)	0.0205 (16)	0.0196 (16)	−0.0017 (11)	0.0034 (11)	−0.0028 (12)
C3	0.0211 (13)	0.0273 (17)	0.0218 (16)	−0.0003 (11)	0.0026 (11)	0.0042 (13)
C4	0.0231 (13)	0.0282 (18)	0.0151 (15)	0.0004 (12)	0.0000 (11)	0.0022 (12)
C5	0.0220 (13)	0.0256 (17)	0.0156 (15)	−0.0015 (12)	0.0000 (11)	−0.0028 (12)
C6	0.0174 (13)	0.0203 (16)	0.0173 (15)	−0.0031 (11)	0.0007 (11)	−0.0022 (11)
C7	0.0165 (12)	0.0216 (16)	0.0173 (15)	−0.0027 (11)	0.0017 (10)	−0.0038 (11)
C8	0.0237 (13)	0.0241 (17)	0.0199 (16)	0.0004 (12)	0.0004 (11)	0.0024 (12)
C9	0.0233 (14)	0.0282 (17)	0.0118 (14)	−0.0020 (12)	−0.0017 (11)	0.0002 (12)
C10	0.0151 (12)	0.0232 (16)	0.0174 (15)	−0.0018 (11)	0.0000 (10)	0.0002 (12)
C11	0.0275 (14)	0.0244 (17)	0.0202 (16)	0.0045 (12)	0.0008 (11)	−0.0006 (12)
C12	0.0172 (12)	0.0201 (15)	0.0166 (15)	−0.0036 (11)	0.0002 (10)	0.0001 (11)
C13	0.0239 (13)	0.0220 (16)	0.0170 (15)	−0.0014 (11)	0.0013 (11)	−0.0005 (12)
C14	0.0249 (14)	0.0184 (16)	0.0178 (15)	−0.0001 (11)	0.0025 (11)	−0.0007 (11)
C15	0.0241 (13)	0.0205 (16)	0.0158 (15)	−0.0029 (11)	0.0019 (11)	−0.0034 (12)
C16	0.0266 (14)	0.0247 (18)	0.0271 (17)	−0.0027 (13)	0.0049 (12)	−0.0022 (13)
N1	0.0237 (11)	0.0243 (14)	0.0148 (12)	−0.0025 (10)	0.0010 (9)	0.0000 (10)
N2	0.0274 (11)	0.0222 (14)	0.0154 (12)	0.0021 (10)	−0.0008 (10)	0.0006 (11)
N3	0.0238 (11)	0.0186 (13)	0.0185 (13)	0.0020 (9)	−0.0007 (9)	−0.0003 (10)
F1	0.0267 (8)	0.0366 (11)	0.0194 (9)	−0.0026 (7)	0.0063 (7)	−0.0057 (7)
F2	0.0598 (11)	0.0226 (10)	0.0330 (11)	0.0107 (8)	0.0116 (9)	−0.0022 (8)
F3	0.0309 (9)	0.0410 (12)	0.0332 (10)	−0.0128 (7)	0.0056 (7)	−0.0185 (8)
S1	0.0268 (4)	0.0227 (5)	0.0193 (4)	0.0011 (3)	−0.0002 (3)	0.0026 (3)
Cl1	0.0410 (4)	0.0286 (5)	0.0140 (4)	0.0020 (3)	−0.0001 (3)	−0.0011 (3)
Cl2	0.0384 (4)	0.0216 (5)	0.0276 (5)	0.0048 (3)	0.0070 (3)	−0.0021 (3)

Geometric parameters (Å, º) top

C1—N1	1.370 (3)	C10—C12	1.481 (4)
C1—C2	1.424 (4)	C10—C11	1.508 (4)
C1—C6	1.433 (4)	C11—H11A	0.9800
C2—C3	1.369 (4)	C11—H11B	0.9800
C2—C16	1.507 (4)	C11—H11C	0.9800
C3—C4	1.413 (4)	C12—C15	1.373 (4)
C3—H3	0.9500	C12—C13	1.434 (4)
C4—C5	1.366 (4)	C13—C14	1.341 (4)
C4—H4	0.9500	C13—H13	0.9500
C5—C6	1.412 (4)	C14—S1	1.715 (3)
C5—H5	0.9500	C14—Cl2	1.721 (3)
C6—C7	1.435 (4)	C15—Cl1	1.715 (3)
C7—C8	1.379 (4)	C15—S1	1.722 (3)
C7—N2	1.383 (3)	C16—F1	1.342 (3)
C8—C9	1.400 (4)	C16—F3	1.349 (3)
C8—H8	0.9500	C16—F2	1.353 (3)
C9—N1	1.323 (3)	N2—N3	1.368 (3)
C9—H9	0.9500	N2—H1	0.85 (3)
C10—N3	1.290 (3)

N1—C1—C2	118.2 (2)	C10—C11—H11A	109.5
N1—C1—C6	123.9 (3)	C10—C11—H11B	109.5
C2—C1—C6	117.9 (2)	H11A—C11—H11B	109.5
C3—C2—C1	121.5 (2)	C10—C11—H11C	109.5
C3—C2—C16	119.5 (3)	H11A—C11—H11C	109.5
C1—C2—C16	119.1 (2)	H11B—C11—H11C	109.5
C2—C3—C4	119.8 (3)	C15—C12—C13	109.7 (2)
C2—C3—H3	120.1	C15—C12—C10	127.5 (2)
C4—C3—H3	120.1	C13—C12—C10	122.8 (2)
C5—C4—C3	120.6 (3)	C14—C13—C12	113.6 (2)
C5—C4—H4	119.7	C14—C13—H13	123.2
C3—C4—H4	119.7	C12—C13—H13	123.2
C4—C5—C6	120.9 (2)	C13—C14—S1	112.9 (2)
C4—C5—H5	119.5	C13—C14—Cl2	127.1 (2)
C6—C5—H5	119.5	S1—C14—Cl2	119.95 (16)
C5—C6—C1	119.2 (3)	C12—C15—Cl1	130.4 (2)
C5—C6—C7	123.9 (2)	C12—C15—S1	113.6 (2)
C1—C6—C7	116.9 (2)	Cl1—C15—S1	115.99 (15)
C8—C7—N2	121.7 (3)	F1—C16—F3	105.6 (2)
C8—C7—C6	118.6 (2)	F1—C16—F2	105.9 (2)
N2—C7—C6	119.7 (2)	F3—C16—F2	105.3 (2)
C7—C8—C9	118.8 (3)	F1—C16—C2	113.8 (2)
C7—C8—H8	120.6	F3—C16—C2	113.7 (2)
C9—C8—H8	120.6	F2—C16—C2	111.8 (2)
N1—C9—C8	126.2 (3)	C9—N1—C1	115.6 (2)
N1—C9—H9	116.9	N3—N2—C7	118.2 (2)
C8—C9—H9	116.9	N3—N2—H1	122.0 (19)
N3—C10—C12	116.4 (2)	C7—N2—H1	119.7 (19)
N3—C10—C11	124.9 (2)	C10—N3—N2	118.0 (2)
C12—C10—C11	118.6 (2)	C14—S1—C15	90.19 (12)

N1—C1—C2—C3	177.8 (2)	C10—C12—C13—C14	176.4 (2)
C6—C1—C2—C3	−1.5 (3)	C12—C13—C14—S1	0.8 (3)
N1—C1—C2—C16	−1.6 (3)	C12—C13—C14—Cl2	−177.83 (18)
C6—C1—C2—C16	179.1 (2)	C13—C12—C15—Cl1	−177.8 (2)
C1—C2—C3—C4	−0.2 (4)	C10—C12—C15—Cl1	4.7 (4)
C16—C2—C3—C4	179.2 (2)	C13—C12—C15—S1	1.1 (3)
C2—C3—C4—C5	1.7 (4)	C10—C12—C15—S1	−176.42 (19)
C3—C4—C5—C6	−1.3 (4)	C3—C2—C16—F1	−117.2 (3)
C4—C5—C6—C1	−0.4 (4)	C1—C2—C16—F1	62.2 (3)
C4—C5—C6—C7	−179.8 (2)	C3—C2—C16—F3	121.8 (3)
N1—C1—C6—C5	−177.4 (2)	C1—C2—C16—F3	−58.8 (3)
C2—C1—C6—C5	1.8 (3)	C3—C2—C16—F2	2.7 (3)
N1—C1—C6—C7	1.9 (3)	C1—C2—C16—F2	−177.8 (2)
C2—C1—C6—C7	−178.8 (2)	C8—C9—N1—C1	−1.0 (4)
C5—C6—C7—C8	176.4 (2)	C2—C1—N1—C9	−179.3 (2)
C1—C6—C7—C8	−2.9 (3)	C6—C1—N1—C9	0.0 (3)
C5—C6—C7—N2	−3.4 (4)	C8—C7—N2—N3	1.3 (3)
C1—C6—C7—N2	177.2 (2)	C6—C7—N2—N3	−178.8 (2)
N2—C7—C8—C9	−178.1 (2)	C12—C10—N3—N2	177.7 (2)
C6—C7—C8—C9	2.1 (3)	C11—C10—N3—N2	0.5 (4)
C7—C8—C9—N1	−0.1 (4)	C7—N2—N3—C10	175.9 (2)
N3—C10—C12—C15	9.2 (4)	C13—C14—S1—C15	−0.2 (2)
C11—C10—C12—C15	−173.4 (2)	Cl2—C14—S1—C15	178.60 (17)
N3—C10—C12—C13	−168.0 (2)	C12—C15—S1—C14	−0.6 (2)
C11—C10—C12—C13	9.4 (3)	Cl1—C15—S1—C14	178.47 (16)
C15—C12—C13—C14	−1.2 (3)

Experimental details

Crystal data
Chemical formula	C₁₆H₁₀Cl₂F₃N₃S
M_r	404.23
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	73
a, b, c (Å)	7.687 (2), 14.392 (5), 14.360 (5)
β (°)	95.053 (9)
V (Å³)	1582.5 (9)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.58
Crystal size (mm)	0.10 × 0.10 × 0.10

Data collection
Diffractometer	Rigaku Mercury CCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	9805, 2897, 2369
R_int	0.082
(sin θ/λ)_max (Å⁻¹)	0.603

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.049, 0.128, 1.06
No. of reflections	2897
No. of parameters	231
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.35, −0.37

Computer programs: CrystalClear (Rigaku, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).

Acknowledgements

ASD thanks the University of Mysore for research facilities.

References

Dutkiewicz, G., Mayekar, A. N., Yathirajan, H. S., Narayana, B. & Kubicki, M. (2010). Acta Cryst. E66, o874. Web of Science CrossRef IUCr Journals Google Scholar
Farrugia, L. J. (1997). ORTEP-3 for Windows. University of Glasgow, Scotland. Google Scholar
Jasinski, J. P., Butcher, R. J., Mayekar, A. N., Yathirajan, H. S., Narayana, B. & Sarojini, B. K. (2010). J. Mol. Struct. 980, 172–181. Web of Science CSD CrossRef CAS Google Scholar
Rigaku (2009). CrystalClear. Rigaku Corporation, Tokyo, Japan. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar

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