organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

Bis(2,3-di­chloro­phen­yl) di­sulfide

aInstituto de Química, Universidad Nacional Autónoma de México, Circuito exterior, Ciudad Universitaria, México, D.F., 04510, Mexico, and bUniversidad Politécnica de Tlaxcala, Av. Universidad Politécnica de Tlaxcala No. 1, San Pedro Xalcaltzinco Municipio de Tepeyanco, Tlaxcala, C.P. 90180, Mexico
*Correspondence e-mail: ericka.santacruz@uptlax.edu.mx

(Received 24 March 2014; accepted 2 April 2014; online 9 April 2014)

The title compound, C12H6Cl4S2, features an S—S bond [2.0252 (8) Å] that bridges two 2,3-di­chloro­phenyl rings with a C—S—S—C torsion angle of 88.35 (11)°. The benzene rings are normal one to the other with a dihedral angle of 89.83 (11)°. The crystal structure features inter­molecular Cl⋯Cl [3.4763 (11) Å] and ππ stacking inter­actions [centroid–centroid distances = 3.696 (1) and 3.641 (2) Å]. Intra­molecular C—H⋯S inter­actions are also observed.

Related literature

For applications of di­sulfide compounds, see: Crowley (1964[Crowley, D. J. (1964). US Patent No. 3 150 186.]); Hashash et al. (2002[Hashash, A., Kirkpatrick, D. L., Lazo, J. S. & Block, L. H. (2002). J. Pharm. Sci. 91, 1686-1692.]); Gomez-Benitez et al. (2006[Gomez-Benitez, V., Baldovino-Pantaleon, O., Herrera-Alvarez, C., Toscano, R. A. & Morales-Morales, D. (2006). Tetrahedron Lett. 47, 5059-5062.]); Yu et al. (2010[Yu, C., Jin, B., Liu, Z. & Zhong, W. (2010). Can. J. Chem. 88, 485-491.]). For various methods of synthesizing disulfides, see: Xiao et al. (2009[Xiao, H., Chen, J., Liu, M., Wu, H. & Ding, J. (2009). Phosphorus Sulfur Silicon Relat. Elem. 184, 2553-2559.]); Shaabani et al. (2008[Shaabani, A., Safari, N., Shoghpour, S. & Hossein, A. R. (2008). Monatsh. Chem. 139, 613-615.]); Ogilby (2010[Ogilby, P. R. (2010). Chem. Soc. Rev. 39, 3181-3209.]). For similar compounds and their crystal structures, see: Deng et al. (2003[Deng, S.-L., Long, L.-S., Xie, S.-Y., Huang, R.-B., Zheng, L.-S. & Ng, S. W. (2003). Acta Cryst. E59, o843-o844.]); Korp & Bernal (1984[Korp, J. D. & Bernal, I. (1984). J. Mol. Struct. 118, 157-164.]); Tang et al. (2011[Tang, J.-M., Feng, Z.-Q. & Cheng, W. (2011). Acta Cryst. E67, o1197.]). For di­sulfide bonds in proteins, see: Sevier & Kaiser (2006[Sevier, C. S. & Kaiser, C. A. (2006). Antioxid. Redox Signal. 8, 797-811.]). For van der Waals radii, see: Bondi (1964[Bondi, A. (1964). J. Phys. Chem. 68, 441-451.]).

[Scheme 1]

Experimental

Crystal data
  • C12H6Cl4S2

  • Mr = 356.09

  • Triclinic, [P \overline 1]

  • a = 7.7149 (10) Å

  • b = 7.7326 (11) Å

  • c = 12.748 (2) Å

  • α = 91.472 (2)°

  • β = 91.233 (3)°

  • γ = 114.859 (2)°

  • V = 689.37 (18) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 1.14 mm−1

  • T = 298 K

  • 0.37 × 0.24 × 0.14 mm

Data collection
  • Bruker SMART APEX CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) Tmin = 0.678, Tmax = 0.862

  • 7044 measured reflections

  • 3130 independent reflections

  • 2594 reflections with I > 2σ(I)

  • Rint = 0.023

Refinement
  • R[F2 > 2σ(F2)] = 0.035

  • wR(F2) = 0.088

  • S = 1.03

  • 3130 reflections

  • 163 parameters

  • H-atom parameters constrained

  • Δρmax = 0.41 e Å−3

  • Δρmin = −0.30 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C6—H6⋯S2 0.93 2.70 3.202 (2) 115
C12—H12⋯S1 0.93 2.70 3.199 (2) 115

Data collection: APEX2 (Bruker, 2012[Bruker (2012). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2012[Bruker (2012). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Introduction top

The di­sulfide bonds are found in proteins (Sevier and Kaiser, 2006), natural products and pharmacologically active compounds. Di­sulfide compounds have shown to exhibit activity as fungicide, mildew-proofing (Crowley, 1964) and anti­tumor agents (Hashash et al., 2002). In organic synthesis di­sulfides are used in cross-coupling reactions catalyzed by transition metal compounds such as palladium, nickel and copper (Gomez-Benitez et al., 2006; Yu et al., 2010).

Several methods for the synthesis of di­sulfides have been reported. These processes involve the oxidative coupling of mercaptans by various oxidants such as molecular oxygen, nitric oxide, solvent-free permanganate, metal ions and promoted by sulfonyl chloride in aqueous media (Xiao et al., 2009; Shaabani et al., 2008; Ogilby, 2010).

Thus, in this report we present the crystal structure of the bis­(2,3-di­chloro­phenyl)­disulfide obtained by a nucleophilic substitution reaction. The structure is represented in figure 1.

Experimental top

Synthesis and crystallization top

The title compound was obtained as a by-product of the reaction between 2-(chloro­methyl)­benzimidazole (0.2 g) and the lead salt of 2,3-di­chloro­benze­thiol ([Pb(SC6H3-2,3-Cl2)2]) (0.337 g) in toluene. The resulting reaction mixture was allowed to proceed under reflux by 8 h after which time the formation of PbCl2 was observed indicating completion of the reaction. The reaction mixture was then filtered through a short Celite plug to afford a colorless solution, the solvent was evaporated under vacuum and the residue column chromatographed (silica gel 60, eluted with 3/2 ethyl acetate/hexane system). Slow Evaporation of the first fraction collected produced crystals of the title compound suitable for X-ray diffraction analysis.

Refinement top

Crystal data, data collection and structure refinement details are summarized in Table 1.

H atoms were included in calculated positions (C—H = 0.93 A for aromatic H) and refined using a riding model with Uiso(H) = 1.2 Ueq of the carrier atoms.

In the refinement six reflections, (2 0 0), (0 1 3), (0 0 1), (-2 1 2), (2 -4 3) and (-1 0 1), were considered as disagreeable and were omitted.

Results and discussion top

The asymmetric unit of the title compound consists of one molecule on the di­sulfide. The rings of the bis­(2,3-di­chloro­phenyl)­disulfide show a dihedral angle of 89.83° between the two planes and a torsion angle C1—S1—S2—C7 of 88.35 (11)°. The value of the C—S—S—C torsion angle is similar to those found in similar compounds, such as bis­(penta­chloro­phenyl)­disulfide (Deng et al., 2003), di­phenyl­disulfide (Korp & Bernal, 1984) and bis­(4-amino-2-chloro­phenyl)­disulfide (Tang et al., 2011). The S—S distance is 2.0252 (8) Å, whereas the C—S distances are 1.784 (2) and 1.7835 (19) Å. These values are similar and close in value to compounds such as bis­(penta­chloro­phenyl)­disulfide with a S—S distance of 2.063 (2) Å and bis­(4-amino-2-chloro­phenyl)­disulfide of 2.0671 (16) Å. The crystal packing is stabilized by π-π and Cl···Cl inter­actions (Figure 2). The π-π inter­actions of the 2,3-di­chloro­phenyl rings presents distances between centroids of 3.696 (1) and 3.641 (2) Å. The Cl1···Cl2 contact distance is of 3.476 Å that is close to the sum of the van der Waals radii of the chloride atoms (Bondi, 1964). The sulphur atoms present C—H···S intra­molecular inter­actions, these values are in the table 1.

Related literature top

For applications of disulfide compounds, see: Crowley (1964); Hashash et al. (2002); Gomez-Benitez et al. (2006); Yu et al. (2010). For synthesis methods for disulfides, see: Xiao et al. (2009); Shaabani et al. (2008); Ogilby (2010). For similar compounds, see: Deng et al. (2003); Korp & Bernal (1984); Tang et al. (2011). For disulfide bonds in proteins, see: Sevier & Kaiser (2006). For van der Waals radii, see: Bondi (1964).

Computing details top

Data collection: APEX2 (Bruker, 2012); cell refinement: SAINT (Bruker, 2012); data reduction: SAINT (Bruker, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound showing 40% probability of displacement ellipsoids for the non-hydrogen atoms.
[Figure 2] Fig. 2. Representation of the π-π and Cl···Cl interactions shown by dashed lines. Hydrogen atoms are omitted.
Bis(2,3-dichlorophenyl) disulfide top
Crystal data top
C12H6Cl4S2Z = 2
Mr = 356.09F(000) = 356
Triclinic, P1Dx = 1.715 Mg m3
a = 7.7149 (10) ÅMo Kα radiation, λ = 0.71073 Å
b = 7.7326 (11) ÅCell parameters from 4288 reflections
c = 12.748 (2) Åθ = 2.8–27.5°
α = 91.472 (2)°µ = 1.14 mm1
β = 91.233 (3)°T = 298 K
γ = 114.859 (2)°Prism, colourless
V = 689.37 (18) Å30.37 × 0.24 × 0.14 mm
Data collection top
Bruker SMART APEX CCD
diffractometer
3130 independent reflections
Radiation source: fine-focus sealed tube2594 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.023
Detector resolution: 8.333 pixels mm-1θmax = 27.5°, θmin = 2.9°
ω scansh = 99
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008)
k = 1010
Tmin = 0.678, Tmax = 0.862l = 1616
7044 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.035Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.088H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0397P)2 + 0.1749P]
where P = (Fo2 + 2Fc2)/3
3130 reflections(Δ/σ)max < 0.001
163 parametersΔρmax = 0.41 e Å3
0 restraintsΔρmin = 0.30 e Å3
Crystal data top
C12H6Cl4S2γ = 114.859 (2)°
Mr = 356.09V = 689.37 (18) Å3
Triclinic, P1Z = 2
a = 7.7149 (10) ÅMo Kα radiation
b = 7.7326 (11) ŵ = 1.14 mm1
c = 12.748 (2) ÅT = 298 K
α = 91.472 (2)°0.37 × 0.24 × 0.14 mm
β = 91.233 (3)°
Data collection top
Bruker SMART APEX CCD
diffractometer
3130 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008)
2594 reflections with I > 2σ(I)
Tmin = 0.678, Tmax = 0.862Rint = 0.023
7044 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0350 restraints
wR(F2) = 0.088H-atom parameters constrained
S = 1.03Δρmax = 0.41 e Å3
3130 reflectionsΔρmin = 0.30 e Å3
163 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cl10.81619 (10)0.72799 (9)0.12199 (5)0.06495 (19)
Cl21.23381 (10)0.95252 (8)0.04969 (5)0.0714 (2)
Cl30.64782 (10)0.26178 (7)0.37441 (5)0.06220 (18)
Cl40.75120 (11)0.22491 (11)0.61516 (5)0.0772 (2)
S10.67633 (8)0.32903 (8)0.20430 (5)0.05302 (16)
S20.64526 (8)0.07120 (7)0.25388 (4)0.05061 (16)
C10.9189 (3)0.4447 (3)0.16702 (13)0.0369 (4)
C20.9766 (3)0.6267 (3)0.12843 (13)0.0372 (4)
C31.1620 (3)0.7266 (3)0.09688 (15)0.0433 (4)
C41.2912 (3)0.6466 (3)0.10343 (18)0.0539 (5)
H41.41590.71380.08250.065*
C51.2338 (3)0.4663 (3)0.14126 (18)0.0548 (5)
H51.32070.41190.14550.066*
C61.0495 (3)0.3650 (3)0.17301 (16)0.0462 (5)
H61.01290.24340.19840.055*
C70.7117 (3)0.1092 (3)0.39027 (14)0.0364 (4)
C80.7107 (3)0.0468 (3)0.44284 (14)0.0378 (4)
C90.7575 (3)0.0306 (3)0.54892 (16)0.0447 (5)
C100.8069 (3)0.1407 (4)0.60354 (17)0.0564 (6)
H100.83950.15170.67480.068*
C110.8078 (3)0.2947 (3)0.55208 (18)0.0561 (6)
H110.84050.40990.58910.067*
C120.7608 (3)0.2809 (3)0.44603 (17)0.0460 (5)
H120.76200.38640.41210.055*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0859 (4)0.0712 (4)0.0671 (4)0.0592 (3)0.0296 (3)0.0276 (3)
Cl20.0806 (4)0.0444 (3)0.0751 (4)0.0115 (3)0.0078 (3)0.0195 (3)
Cl30.0915 (5)0.0416 (3)0.0596 (4)0.0333 (3)0.0146 (3)0.0022 (2)
Cl40.0910 (5)0.0889 (5)0.0677 (4)0.0512 (4)0.0099 (3)0.0389 (3)
S10.0447 (3)0.0628 (3)0.0570 (3)0.0262 (3)0.0104 (2)0.0284 (3)
S20.0609 (3)0.0430 (3)0.0377 (3)0.0117 (2)0.0002 (2)0.0080 (2)
C10.0414 (10)0.0419 (9)0.0290 (9)0.0188 (8)0.0000 (7)0.0059 (7)
C20.0487 (11)0.0412 (9)0.0274 (9)0.0246 (9)0.0011 (7)0.0022 (7)
C30.0511 (12)0.0395 (10)0.0329 (9)0.0128 (9)0.0014 (8)0.0030 (7)
C40.0364 (11)0.0659 (14)0.0526 (13)0.0148 (10)0.0018 (9)0.0069 (11)
C50.0465 (12)0.0707 (14)0.0576 (13)0.0348 (11)0.0038 (10)0.0085 (11)
C60.0476 (11)0.0481 (11)0.0481 (11)0.0251 (9)0.0026 (9)0.0112 (9)
C70.0341 (9)0.0373 (9)0.0347 (9)0.0116 (7)0.0058 (7)0.0057 (7)
C80.0383 (10)0.0372 (9)0.0396 (10)0.0168 (8)0.0093 (8)0.0062 (7)
C90.0377 (10)0.0543 (12)0.0433 (11)0.0197 (9)0.0065 (8)0.0144 (9)
C100.0462 (12)0.0723 (15)0.0395 (11)0.0141 (11)0.0012 (9)0.0010 (10)
C110.0520 (13)0.0469 (12)0.0547 (13)0.0070 (10)0.0028 (10)0.0125 (10)
C120.0456 (11)0.0338 (9)0.0536 (12)0.0115 (8)0.0046 (9)0.0054 (8)
Geometric parameters (Å, º) top
Cl1—C21.7224 (19)C5—C61.380 (3)
Cl2—C31.725 (2)C5—H50.9300
Cl3—C81.7291 (19)C6—H60.9300
Cl4—C91.726 (2)C7—C121.389 (3)
S1—C11.784 (2)C7—C81.392 (3)
S1—S22.0252 (8)C8—C91.381 (3)
S2—C71.7834 (19)C9—C101.378 (3)
C1—C61.386 (3)C10—C111.372 (3)
C1—C21.393 (2)C10—H100.9300
C2—C31.384 (3)C11—C121.382 (3)
C3—C41.378 (3)C11—H110.9300
C4—C51.378 (3)C12—H120.9300
C4—H40.9300
C1—S1—S2105.09 (7)C1—C6—H6120.0
C7—S2—S1105.02 (7)C12—C7—C8119.02 (17)
C6—C1—C2119.06 (18)C12—C7—S2124.42 (15)
C6—C1—S1124.55 (15)C8—C7—S2116.55 (14)
C2—C1—S1116.38 (14)C9—C8—C7120.32 (17)
C3—C2—C1120.36 (18)C9—C8—Cl3120.28 (15)
C3—C2—Cl1120.22 (14)C7—C8—Cl3119.39 (14)
C1—C2—Cl1119.42 (15)C10—C9—C8120.27 (19)
C4—C3—C2120.23 (18)C10—C9—Cl4119.19 (17)
C4—C3—Cl2119.41 (17)C8—C9—Cl4120.53 (16)
C2—C3—Cl2120.36 (16)C11—C10—C9119.6 (2)
C5—C4—C3119.4 (2)C11—C10—H10120.2
C5—C4—H4120.3C9—C10—H10120.2
C3—C4—H4120.3C10—C11—C12120.9 (2)
C4—C5—C6121.0 (2)C10—C11—H11119.5
C4—C5—H5119.5C12—C11—H11119.5
C6—C5—H5119.5C11—C12—C7119.85 (19)
C5—C6—C1119.93 (19)C11—C12—H12120.1
C5—C6—H6120.0C7—C12—H12120.1
S2—S1—C1—C60.06 (18)S1—S2—C7—C123.60 (18)
S2—S1—C1—C2179.34 (12)S1—S2—C7—C8177.28 (13)
C6—C1—C2—C30.2 (3)C12—C7—C8—C90.1 (3)
S1—C1—C2—C3179.52 (14)S2—C7—C8—C9179.02 (14)
C6—C1—C2—Cl1179.31 (14)C12—C7—C8—Cl3179.45 (14)
S1—C1—C2—Cl11.4 (2)S2—C7—C8—Cl30.3 (2)
C1—C2—C3—C40.0 (3)C7—C8—C9—C100.5 (3)
Cl1—C2—C3—C4179.07 (16)Cl3—C8—C9—C10179.76 (16)
C1—C2—C3—Cl2179.68 (14)C7—C8—C9—Cl4178.52 (14)
Cl1—C2—C3—Cl20.6 (2)Cl3—C8—C9—Cl40.8 (2)
C2—C3—C4—C50.3 (3)C8—C9—C10—C110.6 (3)
Cl2—C3—C4—C5179.91 (17)Cl4—C9—C10—C11178.44 (17)
C3—C4—C5—C60.3 (3)C9—C10—C11—C120.3 (3)
C4—C5—C6—C10.0 (3)C10—C11—C12—C70.0 (3)
C2—C1—C6—C50.2 (3)C8—C7—C12—C110.1 (3)
S1—C1—C6—C5179.46 (16)S2—C7—C12—C11179.18 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···S20.932.703.202 (2)115
C12—H12···S10.932.703.199 (2)115
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···S20.932.703.202 (2)114.9
C12—H12···S10.932.703.199 (2)114.8
 

Acknowledgements

This work was supported by CONACYT (grant No. CB2010–154732) and PAPIIT (grants IN201711–3 and IN213214–3). ESJ thanks PROMEP "Apoyo a perfil deseable". RRM and DMM thank Dr Ruben A. Toscano for technical assistance.

References

First citationBondi, A. (1964). J. Phys. Chem. 68, 441–451.  CrossRef CAS Web of Science Google Scholar
First citationBrandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.  Google Scholar
First citationBruker (2012). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationCrowley, D. J. (1964). US Patent No. 3 150 186.  Google Scholar
First citationDeng, S.-L., Long, L.-S., Xie, S.-Y., Huang, R.-B., Zheng, L.-S. & Ng, S. W. (2003). Acta Cryst. E59, o843–o844.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
First citationFarrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationGomez-Benitez, V., Baldovino-Pantaleon, O., Herrera-Alvarez, C., Toscano, R. A. & Morales-Morales, D. (2006). Tetrahedron Lett. 47, 5059–5062.  Web of Science CSD CrossRef CAS Google Scholar
First citationHashash, A., Kirkpatrick, D. L., Lazo, J. S. & Block, L. H. (2002). J. Pharm. Sci. 91, 1686–1692.  Web of Science CrossRef PubMed CAS Google Scholar
First citationKorp, J. D. & Bernal, I. (1984). J. Mol. Struct. 118, 157–164.  CSD CrossRef CAS Web of Science Google Scholar
First citationOgilby, P. R. (2010). Chem. Soc. Rev. 39, 3181–3209.  Web of Science CrossRef CAS PubMed Google Scholar
First citationSevier, C. S. & Kaiser, C. A. (2006). Antioxid. Redox Signal. 8, 797–811.  Web of Science CrossRef PubMed CAS Google Scholar
First citationShaabani, A., Safari, N., Shoghpour, S. & Hossein, A. R. (2008). Monatsh. Chem. 139, 613–615.  Web of Science CrossRef CAS Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSpek, A. L. (2009). Acta Cryst. D65, 148–155.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationTang, J.-M., Feng, Z.-Q. & Cheng, W. (2011). Acta Cryst. E67, o1197.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationXiao, H., Chen, J., Liu, M., Wu, H. & Ding, J. (2009). Phosphorus Sulfur Silicon Relat. Elem. 184, 2553–2559.  Web of Science CrossRef CAS Google Scholar
First citationYu, C., Jin, B., Liu, Z. & Zhong, W. (2010). Can. J. Chem. 88, 485–491.  Web of Science CrossRef CAS 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.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Follow Acta Cryst. E
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds