3-Acetyl-1-(2,4-dimethyl­phen­yl)thio­urea

Gowda, B.T.; Foro, S.; Kumar, S.

doi:10.1107/S1600536812032382

organic compounds

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Volume 68| Part 8| August 2012| Page o2498

https://doi.org/10.1107/S1600536812032382

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3-Acetyl-1-(2,4-dimethylphenyl)thiourea

B. Thimme Gowda,^a ^* Sabine Foro ^b and Sharatha Kumar ^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 15 July 2012; accepted 16 July 2012; online 18 July 2012)

In the crystal structure of the title compound, C₁₁H₁₄N₂OS, the two N—H bonds are anti to each other. There is an intramolecular N—H⋯O hydrogen bond generating an S(6) ring motif.In the crystal, molecules are linked via N—H⋯S hydrogen bonds with an R₂²(8) motif and N—H⋯O hydrogen bonds with an R₂²(12) motif into chains running along [1-10].

Related literature

For studies on the effects of substituents on the structures and other aspects of N-(aryl)-amides, see: Gowda et al. (2001 ); Kumar et al. (2012 ); Shahwar et al. (2012 ), of N-(aryl)-methanesulfonamides, see: Gowda et al. (2007 ) and of N-chloroarylsulfonamides, see: Gowda & Ramachandra (1989 ); Shetty & Gowda (2004 ).

Experimental

Crystal data

C₁₁H₁₄N₂OS
M_r = 222.30
Triclinic, $[P \overline 1]$
a = 5.0510 (7) Å
b = 9.973 (1) Å
c = 12.503 (2) Å
α = 69.15 (1)°
β = 89.43 (1)°
γ = 84.07 (1)°
V = 585.18 (14) Å³
Z = 2
Mo Kα radiation
μ = 0.25 mm⁻¹
T = 293 K
0.44 × 0.44 × 0.20 mm

Data collection

Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]$ ) T_min = 0.897, T_max = 0.951
3701 measured reflections
2393 independent reflections
2094 reflections with I > 2σ(I)
R_int = 0.008

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.097
S = 1.07
2393 reflections
145 parameters
2 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.20 e Å⁻³
Δρ_min = −0.19 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1N⋯O1	0.86 (1)	1.99 (2)	2.6673 (18)	135 (2)
N1—H1N⋯O1ⁱ	0.86 (2)	2.44 (2)	3.121 (2)	137 (2)
N2—H2N⋯S1ⁱⁱ	0.84 (1)	2.55 (2)	3.3711 (14)	168 (2)
Symmetry codes: (i) -x+1, -y+1, -z; (ii) -x+2, -y, -z.

Data collection: CrysAlis CCD (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]$ ); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]$ ); 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: https://doi.org/10.1107/S1600536812032382/bt5977sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812032382/bt5977Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536812032382/bt5977Isup3.cml

checkCIF report

Comment top

Thiourea and its derivatives are known to exhibit a variety of biological activities. As part of our studies on the substituent effects on the structures and other aspects of N-(aryl)-amides (Gowda et al., 2001; Kumar et al., 2012: Shahwar et al., 2012); N-(aryl)-methanesulfonamides (Gowda et al., 2007) and N-chloroarylsulfonamides (Gowda & Ramachandra, 1989; Shetty & Gowda, 2004), in the present work, the crystal structure of 3-acetyl-1-(2,4-dimethylphenyl)thiourea has been determined (Fig. 1).

The conformation of the two N—H bonds are anti to each other. The conformations of the amide C═S and the C═O are also anti to each other and both the bonds are anti to the adjacent N—H bonds, similar to the anti conformation observed in 3-acetyl-1-(2,3-dimethylphenyl)thiourea (I)(Kumar et al., 2012). The adjacent N—H bond is anti to the ortho-methyl group, similar to the anti conformation observed with respect to the ortho- and meta-methyl groups in the benzene ring of (I).

The side chain is oriented itself with respect to the phenyl ring with the C2—C1—N1—C7 and C6—C1—N1—C7 torsion angles of -76.98 (21)° and 105.91 (19)°, compared to the corresponding values of 83.59 (47)° and -99.89 (44)° in (I). The dihedral angle between the phenyl ring and the side chain is 77.5 (1)°, compared to the value of 81.3 (1)° in (I).

The NH hydrogen atom adjacent to the phenyl ring and the amide oxygen are involved in bifurcated hydrogen bonding, exhibiting the simultaneous intra- and inter-molecular hydrogen bonding. In the crystal structure, series of N—H···O and N—H···S intermolecular hydrogen bonds (Table 1) link the molecules into R₂²(8) and R₂²(12) networks (Fig.2).

Related literature top

For studies on the effects of substituents on the structures and other aspects of N-(aryl)-amides, see: Gowda et al. (2001); Kumar et al. (2012); Shahwar et al. (2012), of N-(aryl)-methanesulfonamides, see: Gowda et al. (2007) and of N-chloroarylsulfonamides, see: Gowda & Ramachandra (1989); Shetty & Gowda (2004).

Experimental top

3-Acetyl-1-(2,4-dimethylphenyl)thiourea was synthesized by adding a solution of acetyl chloride (0.10 mol) in acetone (30 ml) dropwise to a suspension of ammonium thiocyanate (0.10 mol) in acetone (30 ml). The reaction mixture was refluxed for 30 min. After cooling to room temperature, a solution of 2,4-dimethylaniline (0.10 mol) in acetone (10 ml) was added and refluxed for 3 h. The reaction mixture was poured into acidified cold water. The precipitated title compound was recrystallized to constant melting point from acetonitrile. The purity of the compound was checked and characterized.

Prism like colourless single crystals used in X-ray diffraction studies were grown in acetonitrile solution by slow evaporation of the solvent at room temperature.

Structure description top

For studies on the effects of substituents on the structures and other aspects of N-(aryl)-amides, see: Gowda et al. (2001); Kumar et al. (2012); Shahwar et al. (2012), of N-(aryl)-methanesulfonamides, see: Gowda et al. (2007) and of N-chloroarylsulfonamides, see: Gowda & Ramachandra (1989); Shetty & Gowda (2004).

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell refinement: CrysAlis CCD (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 the title compound, showing the atom labelling scheme and with displacement ellipsoids drawn at the 50% probability level.
	Fig. 2. Molecular packing of the title compound with hydrogen bonding shown as dashed lines.

3-Acetyl-1-(2,4-dimethylphenyl)thiourea top

Crystal data top

C₁₁H₁₄N₂OS	Z = 2
M_r = 222.30	F(000) = 236
Triclinic, P1	D_x = 1.262 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 5.0510 (7) Å	Cell parameters from 2430 reflections
b = 9.973 (1) Å	θ = 3.3–27.8°
c = 12.503 (2) Å	µ = 0.25 mm⁻¹
α = 69.15 (1)°	T = 293 K
β = 89.43 (1)°	Prism, colourless
γ = 84.07 (1)°	0.44 × 0.44 × 0.20 mm
V = 585.18 (14) Å³

Data collection top

Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector	2393 independent reflections
Radiation source: fine-focus sealed tube	2094 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.008
Rotation method data acquisition using ω and phi scans.	θ_max = 26.4°, θ_min = 3.3°
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009)	h = −6→6
T_min = 0.897, T_max = 0.951	k = −12→12
3701 measured reflections	l = −14→15

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)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.097	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ²(F_o²) + (0.0402P)² + 0.2499P] where P = (F_o² + 2F_c²)/3
2393 reflections	(Δ/σ)_max < 0.001
145 parameters	Δρ_max = 0.20 e Å⁻³
2 restraints	Δρ_min = −0.19 e Å⁻³

Crystal data top

C₁₁H₁₄N₂OS	γ = 84.07 (1)°
M_r = 222.30	V = 585.18 (14) Å³
Triclinic, P1	Z = 2
a = 5.0510 (7) Å	Mo Kα radiation
b = 9.973 (1) Å	µ = 0.25 mm⁻¹
c = 12.503 (2) Å	T = 293 K
α = 69.15 (1)°	0.44 × 0.44 × 0.20 mm
β = 89.43 (1)°

Data collection top

Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector	2393 independent reflections
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009)	2094 reflections with I > 2σ(I)
T_min = 0.897, T_max = 0.951	R_int = 0.008
3701 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	2 restraints
wR(F²) = 0.097	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	Δρ_max = 0.20 e Å⁻³
2393 reflections	Δρ_min = −0.19 e Å⁻³
145 parameters

Special details top

Experimental. Abosrption correction: CrysAlis RED (Oxford Diffraction, 2009) Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

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
S1	1.11565 (9)	0.05240 (5)	0.14186 (4)	0.04794 (16)
O1	0.4331 (3)	0.38737 (13)	−0.04561 (11)	0.0535 (4)
N1	0.7972 (3)	0.28872 (14)	0.12507 (11)	0.0372 (3)
H1N	0.676 (3)	0.3551 (19)	0.0874 (15)	0.045*
N2	0.7355 (3)	0.19052 (15)	−0.01371 (11)	0.0368 (3)
H2N	0.785 (4)	0.1221 (18)	−0.0360 (16)	0.044*
C1	0.9086 (3)	0.29552 (17)	0.22808 (13)	0.0371 (4)
C2	0.8314 (3)	0.20597 (19)	0.33431 (14)	0.0418 (4)
C3	0.9404 (4)	0.2218 (2)	0.43090 (16)	0.0528 (5)
H3	0.8925	0.1627	0.5030	0.063*
C4	1.1165 (4)	0.3217 (2)	0.42369 (18)	0.0578 (5)
C5	1.1864 (5)	0.4092 (2)	0.3166 (2)	0.0620 (6)
H5	1.3043	0.4772	0.3101	0.074*
C6	1.0835 (4)	0.39718 (19)	0.21850 (17)	0.0494 (4)
H6	1.1315	0.4570	0.1467	0.059*
C7	0.8707 (3)	0.18561 (16)	0.08396 (13)	0.0337 (3)
C8	0.5208 (3)	0.28452 (17)	−0.07079 (13)	0.0383 (4)
C9	0.4051 (4)	0.2509 (2)	−0.16736 (16)	0.0524 (5)
H9A	0.3200	0.1639	−0.1369	0.079*
H9B	0.5448	0.2382	−0.2166	0.079*
H9C	0.2767	0.3291	−0.2103	0.079*
C10	0.6410 (4)	0.0967 (2)	0.34550 (17)	0.0568 (5)
H10A	0.7238	0.0220	0.3208	0.085*
H10B	0.4841	0.1426	0.2989	0.085*
H10C	0.5928	0.0553	0.4240	0.085*
C11	1.2348 (6)	0.3306 (3)	0.5323 (2)	0.0884 (9)
H11A	1.4040	0.2730	0.5507	0.133*
H11B	1.1165	0.2952	0.5943	0.133*
H11C	1.2583	0.4291	0.5203	0.133*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0495 (3)	0.0487 (3)	0.0531 (3)	0.01791 (19)	−0.0211 (2)	−0.0330 (2)
O1	0.0681 (8)	0.0424 (7)	0.0520 (7)	0.0189 (6)	−0.0248 (6)	−0.0253 (6)
N1	0.0456 (8)	0.0348 (7)	0.0329 (7)	0.0092 (6)	−0.0116 (6)	−0.0174 (6)
N2	0.0423 (7)	0.0373 (7)	0.0362 (7)	0.0055 (6)	−0.0082 (6)	−0.0222 (6)
C1	0.0430 (9)	0.0359 (8)	0.0359 (8)	0.0103 (7)	−0.0104 (7)	−0.0205 (7)
C2	0.0411 (9)	0.0480 (9)	0.0375 (9)	0.0084 (7)	−0.0061 (7)	−0.0203 (7)
C3	0.0572 (11)	0.0653 (12)	0.0359 (9)	0.0138 (9)	−0.0089 (8)	−0.0233 (9)
C4	0.0681 (12)	0.0603 (12)	0.0554 (12)	0.0191 (10)	−0.0265 (10)	−0.0398 (10)
C5	0.0752 (14)	0.0469 (11)	0.0726 (14)	−0.0021 (10)	−0.0257 (11)	−0.0323 (10)
C6	0.0624 (11)	0.0386 (9)	0.0501 (10)	−0.0018 (8)	−0.0110 (8)	−0.0199 (8)
C7	0.0362 (8)	0.0341 (8)	0.0334 (8)	−0.0004 (6)	−0.0032 (6)	−0.0162 (6)
C8	0.0452 (9)	0.0359 (8)	0.0337 (8)	0.0014 (7)	−0.0081 (7)	−0.0137 (7)
C9	0.0600 (11)	0.0536 (11)	0.0476 (10)	0.0087 (9)	−0.0224 (9)	−0.0262 (9)
C10	0.0529 (11)	0.0671 (13)	0.0461 (10)	−0.0090 (10)	0.0012 (8)	−0.0144 (9)
C11	0.114 (2)	0.0906 (18)	0.0769 (16)	0.0238 (16)	−0.0485 (15)	−0.0576 (15)

Geometric parameters (Å, º) top

S1—C7	1.6774 (16)	C4—C11	1.524 (3)
O1—C8	1.217 (2)	C5—C6	1.385 (3)
N1—C7	1.3239 (19)	C5—H5	0.9300
N1—C1	1.4369 (19)	C6—H6	0.9300
N1—H1N	0.856 (14)	C8—C9	1.502 (2)
N2—C8	1.376 (2)	C9—H9A	0.9600
N2—C7	1.3883 (19)	C9—H9B	0.9600
N2—H2N	0.840 (14)	C9—H9C	0.9600
C1—C6	1.385 (2)	C10—H10A	0.9600
C1—C2	1.390 (2)	C10—H10B	0.9600
C2—C3	1.398 (2)	C10—H10C	0.9600
C2—C10	1.496 (3)	C11—H11A	0.9600
C3—C4	1.382 (3)	C11—H11B	0.9600
C3—H3	0.9300	C11—H11C	0.9600
C4—C5	1.379 (3)

C7—N1—C1	123.94 (13)	N1—C7—N2	117.04 (13)
C7—N1—H1N	117.4 (13)	N1—C7—S1	124.11 (12)
C1—N1—H1N	118.6 (13)	N2—C7—S1	118.86 (11)
C8—N2—C7	128.32 (13)	O1—C8—N2	122.67 (14)
C8—N2—H2N	117.3 (13)	O1—C8—C9	122.70 (15)
C7—N2—H2N	114.1 (13)	N2—C8—C9	114.64 (14)
C6—C1—C2	121.37 (15)	C8—C9—H9A	109.5
C6—C1—N1	118.48 (15)	C8—C9—H9B	109.5
C2—C1—N1	120.09 (15)	H9A—C9—H9B	109.5
C1—C2—C3	117.08 (17)	C8—C9—H9C	109.5
C1—C2—C10	121.75 (15)	H9A—C9—H9C	109.5
C3—C2—C10	121.17 (17)	H9B—C9—H9C	109.5
C4—C3—C2	122.68 (19)	C2—C10—H10A	109.5
C4—C3—H3	118.7	C2—C10—H10B	109.5
C2—C3—H3	118.7	H10A—C10—H10B	109.5
C5—C4—C3	118.36 (17)	C2—C10—H10C	109.5
C5—C4—C11	121.5 (2)	H10A—C10—H10C	109.5
C3—C4—C11	120.1 (2)	H10B—C10—H10C	109.5
C4—C5—C6	120.95 (19)	C4—C11—H11A	109.5
C4—C5—H5	119.5	C4—C11—H11B	109.5
C6—C5—H5	119.5	H11A—C11—H11B	109.5
C5—C6—C1	119.55 (19)	C4—C11—H11C	109.5
C5—C6—H6	120.2	H11A—C11—H11C	109.5
C1—C6—H6	120.2	H11B—C11—H11C	109.5

C7—N1—C1—C6	105.91 (19)	C11—C4—C5—C6	178.1 (2)
C7—N1—C1—C2	−77.0 (2)	C4—C5—C6—C1	−0.2 (3)
C6—C1—C2—C3	−0.8 (2)	C2—C1—C6—C5	0.7 (3)
N1—C1—C2—C3	−177.78 (14)	N1—C1—C6—C5	177.79 (16)
C6—C1—C2—C10	179.50 (17)	C1—N1—C7—N2	177.11 (15)
N1—C1—C2—C10	2.5 (2)	C1—N1—C7—S1	−3.4 (2)
C1—C2—C3—C4	0.3 (3)	C8—N2—C7—N1	−4.4 (3)
C10—C2—C3—C4	−179.90 (17)	C8—N2—C7—S1	176.05 (14)
C2—C3—C4—C5	0.1 (3)	C7—N2—C8—O1	6.3 (3)
C2—C3—C4—C11	−178.16 (18)	C7—N2—C8—C9	−174.26 (16)
C3—C4—C5—C6	−0.2 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O1	0.86 (1)	1.99 (2)	2.6673 (18)	135 (2)
N1—H1N···O1ⁱ	0.86 (2)	2.44 (2)	3.121 (2)	137 (2)
N2—H2N···S1ⁱⁱ	0.84 (1)	2.55 (2)	3.3711 (14)	168 (2)

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

Experimental details

Crystal data
Chemical formula	C₁₁H₁₄N₂OS
M_r	222.30
Crystal system, space group	Triclinic, P1
Temperature (K)	293
a, b, c (Å)	5.0510 (7), 9.973 (1), 12.503 (2)
α, β, γ (°)	69.15 (1), 89.43 (1), 84.07 (1)
V (Å³)	585.18 (14)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.25
Crystal size (mm)	0.44 × 0.44 × 0.20

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	0.897, 0.951
No. of measured, independent and observed [I > 2σ(I)] reflections	3701, 2393, 2094
R_int	0.008
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.097, 1.07
No. of reflections	2393
No. of parameters	145
No. of restraints	2
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.20, −0.19

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···O1	0.856 (14)	1.989 (17)	2.6673 (18)	135.4 (17)
N1—H1N···O1ⁱ	0.86 (2)	2.44 (2)	3.121 (2)	137 (2)
N2—H2N···S1ⁱⁱ	0.840 (14)	2.545 (15)	3.3711 (14)	168.2 (17)

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

Acknowledgements

BTG thanks the University Grants Commission, Government of India, New Delhi, for a special grant under UGC–BSR one-time grant to faculty.

References

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