4-Chloro-2-methyl-N-(3-methyl­phen­yl)benzene­sulfonamide

Gowda, B.T.; Foro, S.; Nirmala, P.G.; Fuess, H.

doi:10.1107/S1600536809051083

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 66| Part 1| January 2010| Page o14

doi:10.1107/S1600536809051083

Open

access

4-Chloro-2-methyl-N-(3-methylphenyl)benzenesulfonamide

B. Thimme Gowda,^a ^* Sabine Foro,^b P. G. Nirmala ^a and Hartmut Fuess ^b

^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 24 November 2009; accepted 26 November 2009; online 4 December 2009)

The N—H bond in the title compound, C₁₄H₁₄ClNO₂S, the dihedral angle between the two benzene rings is 75.5 (1)°. The crystal structure features inversion-related dimers linked by pairs of N—H⋯O hydrogen bonds.

Related literature

For the preparation, see: Savitha & Gowda (2006 ). For our study of the effect of substituents on the crystal structures of N-(aryl)arylsulfonamides, see: Gowda et al. (2009a ,b ,c ). For related structures, see: Gelbrich et al. (2007 ); Perlovich et al. (2006 ).

Experimental

Crystal data

C₁₄H₁₄ClNO₂S
M_r = 295.77
Monoclinic, P 2₁ /c
a = 7.8830 (7) Å
b = 11.602 (1) Å
c = 15.645 (2) Å
β = 90.593 (8)°
V = 1430.8 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.41 mm⁻¹
T = 299 K
0.48 × 0.28 × 0.12 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 = 0.828, T_max = 0.953
5563 measured reflections
2925 independent reflections
1980 reflections with I > 2σ(I)
R_int = 0.014

Refinement

R[F² > 2σ(F²)] = 0.052
wR(F²) = 0.156
S = 1.03
2925 reflections
177 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.36 e Å⁻³
Δρ_min = −0.44 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1N⋯O2ⁱ	0.82 (4)	2.10 (4)	2.925 (3)	176 (3)
Symmetry code: (i) -x+1, -y, -z+2.

Data collection: CrysAlis CCD (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]$ ); cell refinement: CrysAlis RED (Oxford Diffraction, 2009 $[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]$ ); 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/S1600536809051083/ci2978sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809051083/ci2978Isup2.hkl

checkCIF report

Comment top

As part of a study of the substituent effects on the structures of N-(aryl)arylsulfonamides (Gowda et al., 2009a,b,c), in the present work the structure of 4-chloro-2-methyl-N- (3-methylphenyl)benzenesulfonamide (I) has been determined (Fig. 1). The conformation of the N—H bond is anti to the meta-methyl group in the aniline benzene ring. The molecule is bent at the N atom with the C1—S1—N1—C7 torsion angle of 77.2 (3)°, compared to the values of 73.0 (3)° in 4-chloro-2-methyl-N-(2-methylphenyl)benzenesulfonamide (II) (Gowda et al., 2009c), 74.8°(4) in 2-methyl-4-chloro-N-(2-chlorophenyl)benzenesulfonamide (III) (Gowda et al., 2009b) and -61.9 (4)° (molecule 1) and 69.7 (4)° (molecule 2) in the two independent molecules of 4-chloro-2-methyl-N- (phenyl)benzenesulfonamide (III) (Gowda et al., 2009a). The two benzene rings are tilted relative to each other by 75.5 (1)°, compared to the values of 45.8 (1)° in (II), 45.5 (2)° in (III), and 86.6 (2)° (molecule 1) and 83.0 (2)° (molecule 2) in the two independent molecules of (IV). The other bond parameters in (I) are similar to those observed in (II), (III), (IV) 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 preparation, see: Savitha & Gowda (2006). For our study of the effect of substituents on the crystal structures of N-(aryl)arylsulfonamides, see: Gowda et al. (2009a,b,c). For related structures, see: Gelbrich et al. (2007); Perlovich et al. (2006).

Experimental top

A solution of m-chlorotoluene (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 4-chloro-2-methylbenzenesulfonylchloride was treated with m-toluidine 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 4-chloro-2-methyl-N- (3-methylphenyl)benzenesulfonamide 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 single crystals used in X-ray diffraction studies were grown in ethanolic solution by 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 the title compound, showing the atom labeling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented as small spheres of arbitrary radii.
	Fig. 2. Molecular packing of the title compound with hydrogen bonding shown as dashed lines.

4-Chloro-2-methyl-N-(3-methylphenyl)benzenesulfonamide top

Crystal data top

C₁₄H₁₄ClNO₂S	F(000) = 616
M_r = 295.77	D_x = 1.373 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2116 reflections
a = 7.8830 (7) Å	θ = 2.6–27.9°
b = 11.602 (1) Å	µ = 0.41 mm⁻¹
c = 15.645 (2) Å	T = 299 K
β = 90.593 (8)°	Prism, colourless
V = 1430.8 (3) Å³	0.48 × 0.28 × 0.12 mm
Z = 4

Data collection top

Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector	2925 independent reflections
Radiation source: fine-focus sealed tube	1980 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.014
Rotation method data acquisition using ω and ϕ scans	θ_max = 26.4°, θ_min = 2.6°
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009)	h = −9→6
T_min = 0.828, T_max = 0.953	k = −11→14
5563 measured reflections	l = −19→18

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)] = 0.052	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.156	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ²(F_o²) + (0.0757P)² + 0.6262P] where P = (F_o² + 2F_c²)/3
2925 reflections	(Δ/σ)_max = 0.020
177 parameters	Δρ_max = 0.36 e Å⁻³
0 restraints	Δρ_min = −0.44 e Å⁻³

Crystal data top

C₁₄H₁₄ClNO₂S	V = 1430.8 (3) Å³
M_r = 295.77	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 7.8830 (7) Å	µ = 0.41 mm⁻¹
b = 11.602 (1) Å	T = 299 K
c = 15.645 (2) Å	0.48 × 0.28 × 0.12 mm
β = 90.593 (8)°

Data collection top

Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector	2925 independent reflections
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009)	1980 reflections with I > 2σ(I)
T_min = 0.828, T_max = 0.953	R_int = 0.014
5563 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.052	0 restraints
wR(F²) = 0.156	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.36 e Å⁻³
2925 reflections	Δρ_min = −0.44 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	0.6521 (3)	0.1989 (2)	0.83780 (16)	0.0484 (6)
C2	0.8133 (4)	0.1933 (2)	0.87588 (18)	0.0552 (7)
C3	0.9404 (4)	0.2588 (3)	0.8394 (2)	0.0679 (8)
H3	1.0494	0.2563	0.8627	0.081*
C4	0.9084 (4)	0.3278 (3)	0.7692 (2)	0.0675 (8)
C5	0.7500 (5)	0.3331 (3)	0.7328 (2)	0.0725 (9)
H5	0.7292	0.3802	0.6858	0.087*
C6	0.6223 (4)	0.2679 (3)	0.76688 (18)	0.0616 (8)
H6	0.5145	0.2700	0.7421	0.074*
C7	0.3599 (3)	0.2701 (2)	0.99538 (18)	0.0509 (6)
C8	0.3539 (3)	0.3658 (2)	0.94325 (19)	0.0584 (7)
H8	0.4012	0.3622	0.8891	0.070*
C9	0.2787 (4)	0.4672 (3)	0.9703 (2)	0.0630 (8)
C10	0.2096 (5)	0.4692 (3)	1.0506 (2)	0.0882 (11)
H10	0.1577	0.5362	1.0700	0.106*
C11	0.2159 (5)	0.3740 (4)	1.1028 (2)	0.0929 (12)
H11	0.1698	0.3776	1.1572	0.111*
C12	0.2895 (4)	0.2737 (3)	1.07543 (19)	0.0663 (8)
H12	0.2919	0.2090	1.1105	0.080*
C13	0.8530 (4)	0.1198 (3)	0.9571 (2)	0.0703 (9)
H13A	0.8313	0.0400	0.9451	0.084*
H13B	0.7823	0.1448	1.0032	0.084*
H13C	0.9701	0.1295	0.9732	0.084*
C14	0.2762 (5)	0.5716 (3)	0.9131 (3)	0.0857 (11)
H14A	0.2078	0.5560	0.8634	0.103*
H14B	0.3898	0.5896	0.8961	0.103*
H14C	0.2293	0.6359	0.9435	0.103*
N1	0.4428 (4)	0.1662 (2)	0.97214 (17)	0.0692 (8)
H1N	0.445 (4)	0.118 (3)	1.011 (2)	0.083*
O1	0.3367 (3)	0.1432 (2)	0.82291 (15)	0.0752 (6)
O2	0.5297 (3)	0.00166 (16)	0.88893 (14)	0.0708 (6)
Cl1	1.07032 (16)	0.41278 (11)	0.72879 (9)	0.1237 (5)
S1	0.47841 (9)	0.11958 (6)	0.87689 (5)	0.0572 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0546 (15)	0.0446 (13)	0.0461 (14)	0.0116 (12)	−0.0020 (11)	−0.0040 (12)
C2	0.0599 (16)	0.0479 (15)	0.0576 (16)	0.0147 (13)	−0.0036 (13)	−0.0032 (13)
C3	0.0566 (17)	0.0603 (19)	0.087 (2)	0.0091 (15)	0.0030 (16)	−0.0136 (17)
C4	0.077 (2)	0.0543 (17)	0.071 (2)	0.0048 (15)	0.0271 (17)	−0.0090 (16)
C5	0.099 (3)	0.066 (2)	0.0528 (17)	0.0143 (19)	0.0131 (17)	0.0072 (15)
C6	0.0692 (19)	0.0651 (18)	0.0504 (16)	0.0146 (15)	−0.0034 (14)	0.0023 (14)
C7	0.0479 (14)	0.0486 (15)	0.0563 (16)	−0.0009 (11)	0.0032 (12)	−0.0036 (12)
C8	0.0590 (16)	0.0532 (17)	0.0631 (18)	0.0017 (13)	0.0068 (14)	−0.0016 (14)
C9	0.0591 (18)	0.0513 (16)	0.078 (2)	0.0032 (13)	−0.0098 (15)	−0.0089 (15)
C10	0.104 (3)	0.081 (3)	0.080 (3)	0.036 (2)	−0.004 (2)	−0.022 (2)
C11	0.107 (3)	0.108 (3)	0.064 (2)	0.036 (2)	0.015 (2)	−0.009 (2)
C12	0.0658 (18)	0.073 (2)	0.0604 (18)	0.0085 (15)	0.0035 (15)	0.0038 (15)
C13	0.0676 (19)	0.0651 (19)	0.078 (2)	0.0248 (15)	−0.0330 (16)	0.0020 (16)
C14	0.094 (3)	0.0524 (19)	0.111 (3)	0.0071 (18)	−0.014 (2)	0.0019 (19)
N1	0.095 (2)	0.0514 (15)	0.0613 (16)	0.0169 (14)	0.0169 (14)	0.0085 (12)
O1	0.0598 (12)	0.0789 (15)	0.0866 (16)	0.0024 (11)	−0.0155 (11)	−0.0093 (12)
O2	0.0932 (15)	0.0446 (11)	0.0749 (14)	0.0048 (10)	0.0039 (11)	−0.0041 (10)
Cl1	0.1293 (10)	0.1064 (9)	0.1367 (11)	−0.0264 (7)	0.0632 (8)	−0.0064 (7)
S1	0.0630 (5)	0.0485 (4)	0.0600 (5)	0.0044 (3)	−0.0008 (3)	−0.0033 (3)

Geometric parameters (Å, º) top

C1—C6	1.387 (4)	C9—C10	1.375 (5)
C1—C2	1.399 (4)	C9—C14	1.506 (5)
C1—S1	1.764 (3)	C10—C11	1.375 (5)
C2—C3	1.386 (4)	C10—H10	0.93
C2—C13	1.560 (4)	C11—C12	1.371 (5)
C3—C4	1.380 (5)	C11—H11	0.93
C3—H3	0.93	C12—H12	0.93
C4—C5	1.369 (5)	C13—H13A	0.96
C4—Cl1	1.737 (3)	C13—H13B	0.96
C5—C6	1.371 (4)	C13—H13C	0.96
C5—H5	0.93	C14—H14A	0.96
C6—H6	0.93	C14—H14B	0.96
C7—C12	1.375 (4)	C14—H14C	0.96
C7—C8	1.378 (4)	N1—S1	1.613 (3)
C7—N1	1.420 (3)	N1—H1N	0.82 (4)
C8—C9	1.386 (4)	O1—S1	1.420 (2)
C8—H8	0.93	O2—S1	1.438 (2)

C6—C1—C2	120.9 (3)	C9—C10—H10	119.4
C6—C1—S1	116.9 (2)	C12—C11—C10	120.6 (3)
C2—C1—S1	122.2 (2)	C12—C11—H11	119.7
C3—C2—C1	117.2 (3)	C10—C11—H11	119.7
C3—C2—C13	119.7 (3)	C11—C12—C7	119.1 (3)
C1—C2—C13	123.1 (3)	C11—C12—H12	120.4
C4—C3—C2	121.2 (3)	C7—C12—H12	120.4
C4—C3—H3	119.4	C2—C13—H13A	109.5
C2—C3—H3	119.4	C2—C13—H13B	109.5
C5—C4—C3	121.0 (3)	H13A—C13—H13B	109.5
C5—C4—Cl1	119.6 (3)	C2—C13—H13C	109.5
C3—C4—Cl1	119.3 (3)	H13A—C13—H13C	109.5
C4—C5—C6	119.0 (3)	H13B—C13—H13C	109.5
C4—C5—H5	120.5	C9—C14—H14A	109.5
C6—C5—H5	120.5	C9—C14—H14B	109.5
C5—C6—C1	120.7 (3)	H14A—C14—H14B	109.5
C5—C6—H6	119.7	C9—C14—H14C	109.5
C1—C6—H6	119.7	H14A—C14—H14C	109.5
C12—C7—C8	120.2 (3)	H14B—C14—H14C	109.5
C12—C7—N1	116.7 (3)	C7—N1—S1	127.3 (2)
C8—C7—N1	123.0 (3)	C7—N1—H1N	114 (3)
C7—C8—C9	121.0 (3)	S1—N1—H1N	116 (3)
C7—C8—H8	119.5	O1—S1—O2	118.67 (14)
C9—C8—H8	119.5	O1—S1—N1	109.96 (14)
C10—C9—C8	117.9 (3)	O2—S1—N1	104.43 (13)
C10—C9—C14	121.7 (3)	O1—S1—C1	107.55 (13)
C8—C9—C14	120.3 (3)	O2—S1—C1	108.88 (13)
C11—C10—C9	121.1 (3)	N1—S1—C1	106.78 (14)
C11—C10—H10	119.4

C6—C1—C2—C3	−0.3 (4)	C8—C9—C10—C11	0.5 (5)
S1—C1—C2—C3	179.6 (2)	C14—C9—C10—C11	−178.6 (4)
C6—C1—C2—C13	178.3 (3)	C9—C10—C11—C12	−0.9 (6)
S1—C1—C2—C13	−1.7 (4)	C10—C11—C12—C7	1.1 (6)
C1—C2—C3—C4	0.8 (4)	C8—C7—C12—C11	−0.9 (5)
C13—C2—C3—C4	−177.8 (3)	N1—C7—C12—C11	176.6 (3)
C2—C3—C4—C5	−0.5 (5)	C12—C7—N1—S1	157.2 (2)
C2—C3—C4—Cl1	177.3 (2)	C8—C7—N1—S1	−25.5 (4)
C3—C4—C5—C6	−0.5 (5)	C7—N1—S1—O1	−39.2 (3)
Cl1—C4—C5—C6	−178.2 (2)	C7—N1—S1—O2	−167.5 (3)
C4—C5—C6—C1	1.0 (4)	C7—N1—S1—C1	77.2 (3)
C2—C1—C6—C5	−0.5 (4)	C6—C1—S1—O1	1.2 (2)
S1—C1—C6—C5	179.5 (2)	C2—C1—S1—O1	−178.8 (2)
C12—C7—C8—C9	0.5 (4)	C6—C1—S1—O2	130.9 (2)
N1—C7—C8—C9	−176.8 (3)	C2—C1—S1—O2	−49.0 (3)
C7—C8—C9—C10	−0.2 (4)	C6—C1—S1—N1	−116.8 (2)
C7—C8—C9—C14	178.9 (3)	C2—C1—S1—N1	63.2 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O2ⁱ	0.82 (4)	2.10 (4)	2.925 (3)	176 (3)

Symmetry code: (i) −x+1, −y, −z+2.

Experimental details

Crystal data
Chemical formula	C₁₄H₁₄ClNO₂S
M_r	295.77
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	299
a, b, c (Å)	7.8830 (7), 11.602 (1), 15.645 (2)
β (°)	90.593 (8)
V (Å³)	1430.8 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.41
Crystal size (mm)	0.48 × 0.28 × 0.12

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	0.828, 0.953
No. of measured, independent and observed [I > 2σ(I)] reflections	5563, 2925, 1980
R_int	0.014
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.052, 0.156, 1.03
No. of reflections	2925
No. of parameters	177
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.36, −0.44

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	0.82 (4)	2.10 (4)	2.925 (3)	176 (3)

Symmetry code: (i) −x+1, −y, −z+2.

References

Gelbrich, T., Hursthouse, M. B. & Threlfall, T. L. (2007). Acta Cryst. B63, 621–632. Web of Science CSD CrossRef IUCr Journals Google Scholar
Gowda, B. T., Foro, S., Nirmala, P. G., Babitha, K. S. & Fuess, H. (2009a). Acta Cryst. E65, o476. Web of Science CSD CrossRef IUCr Journals Google Scholar
Gowda, B. T., Foro, S., Nirmala, P. G., Babitha, K. S. & Fuess, H. (2009b). Acta Cryst. E65, o717. Web of Science CSD CrossRef IUCr Journals Google Scholar
Gowda, B. T., Foro, S., Nirmala, P. G., Terao, H. & Fuess, H. (2009c). Acta Cryst. E65, o800. Web of Science CSD CrossRef IUCr Journals Google Scholar
Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England. Google Scholar
Perlovich, G. L., Tkachev, V. V., Schaper, K.-J. & Raevsky, O. A. (2006). Acta Cryst. E62, o780–o782. Web of Science CSD CrossRef IUCr Journals Google Scholar
Savitha, M. B. & Gowda, B. T. (2006). Z. Naturforsch. Teil A, 60, 600–606. 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.

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 66| Part 1| January 2010| Page o14

doi:10.1107/S1600536809051083

Open

access