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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

5-Bromo-4-(3,5-di­bromo-2-hy­dr­oxy­phen­yl)-2-(piperidin-1-yl)-1,3-di­thiol-2-ylium bromide

aDepartment of Chemistry, University of Craiova, 107I Calea Bucuresti, Craiova, Romania, bChemisches Institut der Otto-von-Guericke-Universität, Universitätsplatz 2, D-39116 Magdeburg, Germany, and cDepartment of Chemistry, "Al. I. Cuza" University Iasi, 11 Carol I Bvd, Iasi 700506, Romania
*Correspondence e-mail: lbirsa@uaic.ro

(Received 30 May 2013; accepted 9 June 2013; online 15 June 2013)

In the title salt, C14H13Br3NOS2+·Br, synthesized by bromination of mesoionic 2-[2-(piperidin-1-yl)-1,3-di­thiol-2-ylium-4-yl]phenolate in glacial acetic acid, the dihedral angle between the 1,3-di­thiol­ium ring and the phenolic substituent ring is 45.9 (3)° due to the steric influence of the ortho-Br group on the 1,3-di­thiol­ium ring. The piperidine ring adopts a chair conformation. In the crystal, the cation and anion are linked by an O—H⋯Br hydrogen bond.

Related literature

For applications of 1,3-di­thiol­ium salts, see: Narita & Pittman (1976[Narita, M. & Pittman, C. U. Jr (1976). Synthesis, pp. 489-514.]); Bryce (2000[Bryce, M. R. (2000). J. Mater. Chem. 10, 589-598.]); Birsa & Ganju (2003[Birsa, M. L. & Ganju, D. (2003). J. Phys. Org. Chem. 16, 207-212.]); For the structure of 2-ethyl­thio-4,5-bis­(tri­fluoro­meth­yl)-1,3-di­thiol-2-ylium hexa­chloro­stibiate, see: Frasch et al. (1993[Frasch, M., Mono, S., Pritzkow, H. & Sundermeyer, W. (1993). Chem. Ber. 126, 273-275.])

[Scheme 1]

Experimental

Crystal data
  • C14H13Br3NOS2+·Br

  • Mr = 595.01

  • Monoclinic, P 21 /c

  • a = 10.484 (2) Å

  • b = 7.9240 (16) Å

  • c = 21.396 (4) Å

  • β = 95.16 (3)°

  • V = 1770.4 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 9.33 mm−1

  • T = 153 K

  • 0.26 × 0.13 × 0.05 mm

Data collection
  • Stoe IPDS 2T area-detector diffractometer

  • Absorption correction: for a sphere [modified Dwiggins (1975[Dwiggins, C. W. (1975). Acta Cryst. A31, 146-148.])] Tmin = 0.047, Tmax = 0.073

  • 19422 measured reflections

  • 4399 independent reflections

  • 3413 reflections with I > 2σ(I)

  • Rint = 0.132

Refinement
  • R[F2 > 2σ(F2)] = 0.061

  • wR(F2) = 0.137

  • S = 1.08

  • 4399 reflections

  • 200 parameters

  • H-atom parameters constrained

  • Δρmax = 1.52 e Å−3

  • Δρmin = −1.03 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O—H0⋯Br4 0.84 2.30 3.120 (5) 167

Data collection: X-AREA (Stoe & Cie, 2002[Stoe & Cie (2002). X-AREA. Stoe & Cie, Darmstadt, Germany.]); cell refinement: X-AREA; data reduction: X-AREA; 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: XP in SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

1,3-Dithiolium salts are well known precursors of tetrathiafulvalenes (Narita & Pittman, 1976), which in turn are notable π-electron donors in organic superconductors (Bryce, 2000). Of special interest are systems where the donor moiety is linked through a σ- or π-bonded bridge to the acceptor moiety. In this context, it has been shown that 1,3-dithiolium ions can also serve as acceptor moieties in intramolecular charge-transfer systems (Birsa & Ganju, 2003). The title compound, C14H13Br3NOS2+ Br-, has been synthesized in good yield (84%), by bromination of mesoionic 2-[2-(piperidin-1-yl)-1,3-dithiol-2-ylium-4-yl]phenolate in glacial acetic acid. In this salt (Fig. 1), the benzene and 1,3-dithiolium planes form a dihedral angle of 45.9 (3) °, this deviation from planarity most likely being due to the bulky bromine substituent in the 5-position of 1,3-dithiolium ring. Moreover, no hydrogen bond was found between the phenolic O—H group and the S2 atom. Instead, a hydrogen bond between the O—H group and the bromide counter-anion is present (Table 1). Also present in the crystal is a weak intermolecular C13—H···Br2i hydrogen bond [3.836 (7) Å], a short intermolecular Br3···Br4ii interaction [3.3062 (11) Å] and a weak dithiolium to phenyl ring ππ interaction [minimum ring centroid separation, 3.801 (4) Å] [for symmetry code (i) -x + 1, y + 1/2, -z + 1/2; (ii) -x + 1, y - 1/2, -z + 1/2].

Related literature top

For applications of 1,3-dithiolium salts, see: Narita & Pittman (1976); Bryce (2000); Birsa & Ganju (2003); For the structure of 2-ethylthio-4,5-bis(trifluoromethyl)-1,3-dithiol-2-ylium hexachlorostibiate, see: Frasch et al. (1993)

Experimental top

To a solution of 0.277 g (1 mmol) of 2-[2-(piperidin-1-yl)-1,3-dithiol-2-ylium-4-yl]phenolate (Birsa & Ganju, 2003) in 20 ml of glacial acetic acid, a solution of 0.15 ml (3 mmol) of bromine in 2 ml of glacial acetic acid was added dropwise. After complete consumption of the bromine the reaction mixture was poured into water and the precipitate filtered off. Crystallization from ethanol give 0.5 g (84%) of pure product as colorless crystals [m.p. 501–502 K (dec.)]. IR (ATR): νmax 2946, 2764, 2551, 1567, 1523, 1439, 1248, 1229, 868, 852, 687 cm-1. 1H NMR (300 MHz, DMSO-d6): δ = 1.77 (m, 6H, 3CH2), 3.89 (m, 4H, 2CH2-N), 7.55 (d, 4 J=2.1 Hz, 1H), 7.88 (d, 4 J=2.1 Hz, 1H), 10.63 (s, 1H, OH). 13C{1H} NMR (75 MHz, DMSO-d6): δ = 21.6 (t), 24.8 (t), 24.9 (t), 56.5 (t), 57.5 (t), 107.1 (s), 111.4 (s), 113.8 (s), 119.4 (s), 130.3 (s), 133.5 (d), 137.9 (d), 152.5 (s), 184.6 (s).

Refinement top

The C-bound H-atoms were included at calculated positions and treated using a riding model, with aromatic C—H = 0.95 Å, and methylene C—H = 0.99 Å, and Uiso(H) = 1.2Ueq(C). The phenolic H-atom (H0) was located in a difference Fourier and was also allowed to ride in the refinement, with Uiso(H) = 1.5Ueq(O).

Computing details top

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA (Stoe & Cie, 2002); data reduction: X-AREA (Stoe & Cie, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The atom numberimg scheme for the cation and anion species of the title salt. Thermal ellipsoids are drawn at the 50% probability level.
5-Bromo-4-(3,5-dibromo-2-hydroxyphenyl)-2-(piperidin-1-yl)-1,3-dithiol-2-ylium bromide top
Crystal data top
C14H13Br3NOS2+·BrF(000) = 1136
Mr = 595.01Dx = 2.232 Mg m3
Monoclinic, P21/cMelting point = 501–502 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 10.484 (2) ÅCell parameters from 17310 reflections
b = 7.9240 (16) Åθ = 2.6–29.6°
c = 21.396 (4) ŵ = 9.33 mm1
β = 95.16 (3)°T = 153 K
V = 1770.4 (6) Å3Plate, colourless
Z = 40.26 × 0.13 × 0.05 mm
Data collection top
Stoe IPDS 2T area-detector
diffractometer
4399 independent reflections
Radiation source: fine-focus sealed tube3413 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.132
Detector resolution: 6.67 pixels mm-1θmax = 28.3°, θmin = 2.0°
rotation method scansh = 1313
Absorption correction: for a sphere
[modified Dwiggins (1975)]
k = 109
Tmin = 0.047, Tmax = 0.073l = 2828
19422 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)] = 0.061Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.137H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.0656P)2]
where P = (Fo2 + 2Fc2)/3
4399 reflections(Δ/σ)max < 0.001
200 parametersΔρmax = 1.52 e Å3
0 restraintsΔρmin = 1.03 e Å3
Crystal data top
C14H13Br3NOS2+·BrV = 1770.4 (6) Å3
Mr = 595.01Z = 4
Monoclinic, P21/cMo Kα radiation
a = 10.484 (2) ŵ = 9.33 mm1
b = 7.9240 (16) ÅT = 153 K
c = 21.396 (4) Å0.26 × 0.13 × 0.05 mm
β = 95.16 (3)°
Data collection top
Stoe IPDS 2T area-detector
diffractometer
4399 independent reflections
Absorption correction: for a sphere
[modified Dwiggins (1975)]
3413 reflections with I > 2σ(I)
Tmin = 0.047, Tmax = 0.073Rint = 0.132
19422 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0610 restraints
wR(F2) = 0.137H-atom parameters constrained
S = 1.08Δρmax = 1.52 e Å3
4399 reflectionsΔρmin = 1.03 e Å3
200 parameters
Special details top

Experimental. Absorption correction: Interpolation using International Tables Vol. C, Table 6.3.3.3 for values of µR in the range 0-2.5, and International Tables Vol. II, Table 5.3.6B for µR in the range 2.6–10.0. The interpolation procedure (Dwiggins, 1975) is used with some modification.

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
xyzUiso*/Ueq
N0.2558 (5)1.1734 (8)0.0481 (2)0.0247 (12)
O0.6690 (4)0.9340 (7)0.1718 (2)0.0250 (10)
H00.71420.99250.14960.038*
Br10.93336 (6)0.89688 (11)0.24480 (3)0.03220 (19)
Br20.68140 (7)1.21285 (10)0.43451 (3)0.03022 (18)
Br30.27602 (6)0.94400 (9)0.29348 (3)0.02288 (16)
Br40.80174 (7)1.19802 (10)0.09104 (3)0.03071 (18)
S10.20158 (14)1.0731 (2)0.16132 (7)0.0216 (3)
S20.46012 (15)1.1582 (2)0.13143 (7)0.0246 (3)
C10.5624 (6)1.0722 (8)0.2511 (3)0.0201 (12)
C20.6747 (6)0.9999 (9)0.2309 (3)0.0210 (12)
C30.7839 (6)0.9945 (9)0.2716 (3)0.0249 (13)
C40.7862 (7)1.0585 (10)0.3319 (3)0.0270 (14)
H40.86261.05420.35940.032*
C50.6763 (7)1.1286 (9)0.3516 (3)0.0249 (13)
C60.5634 (6)1.1376 (8)0.3120 (3)0.0219 (12)
H60.48861.18710.32600.026*
C70.4449 (6)1.0855 (9)0.2082 (3)0.0227 (13)
C80.3247 (6)1.0477 (9)0.2205 (3)0.0221 (12)
C90.3003 (5)1.1413 (9)0.1063 (3)0.0208 (12)
C100.1219 (6)1.1466 (11)0.0266 (3)0.0287 (15)
H10A0.07091.13810.06320.034*
H10B0.11261.03930.00300.034*
C110.0718 (7)1.2914 (10)0.0152 (3)0.0306 (15)
H11A0.07501.39770.00920.037*
H11B0.01851.26970.03090.037*
C120.1533 (8)1.3085 (11)0.0705 (3)0.0340 (16)
H12A0.14531.20470.09630.041*
H12B0.12181.40460.09720.041*
C130.2923 (7)1.3368 (10)0.0478 (3)0.0297 (15)
H13A0.30151.44820.02700.036*
H13B0.34401.33830.08430.036*
C140.3436 (7)1.2010 (11)0.0022 (3)0.0291 (15)
H14A0.35341.09420.02530.035*
H14B0.42911.23480.01710.035*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N0.024 (3)0.033 (3)0.017 (2)0.001 (2)0.0002 (19)0.003 (2)
O0.028 (2)0.029 (3)0.0191 (19)0.002 (2)0.0093 (17)0.0033 (19)
Br10.0235 (3)0.0384 (4)0.0354 (3)0.0043 (3)0.0065 (3)0.0071 (3)
Br20.0406 (4)0.0313 (4)0.0183 (3)0.0038 (3)0.0001 (2)0.0008 (3)
Br30.0253 (3)0.0252 (3)0.0188 (3)0.0002 (2)0.0056 (2)0.0019 (2)
Br40.0434 (4)0.0259 (4)0.0247 (3)0.0012 (3)0.0133 (3)0.0004 (3)
S10.0211 (6)0.0256 (8)0.0184 (6)0.0011 (6)0.0037 (5)0.0009 (6)
S20.0218 (7)0.0335 (9)0.0186 (6)0.0036 (6)0.0024 (5)0.0035 (6)
C10.025 (3)0.017 (3)0.018 (2)0.000 (2)0.003 (2)0.002 (2)
C20.028 (3)0.017 (3)0.018 (2)0.004 (2)0.002 (2)0.001 (2)
C30.025 (3)0.021 (3)0.029 (3)0.002 (3)0.008 (2)0.002 (3)
C40.027 (3)0.028 (4)0.025 (3)0.002 (3)0.006 (2)0.005 (3)
C50.036 (3)0.023 (3)0.015 (2)0.006 (3)0.002 (2)0.001 (2)
C60.030 (3)0.015 (3)0.021 (3)0.001 (2)0.004 (2)0.000 (2)
C70.031 (3)0.020 (3)0.017 (3)0.001 (2)0.002 (2)0.000 (2)
C80.028 (3)0.022 (3)0.016 (2)0.003 (3)0.001 (2)0.000 (2)
C90.016 (2)0.022 (3)0.024 (3)0.001 (2)0.002 (2)0.000 (2)
C100.024 (3)0.038 (4)0.025 (3)0.001 (3)0.002 (2)0.002 (3)
C110.027 (3)0.033 (4)0.033 (3)0.003 (3)0.004 (3)0.002 (3)
C120.046 (4)0.034 (4)0.022 (3)0.004 (3)0.002 (3)0.007 (3)
C130.043 (4)0.028 (4)0.018 (3)0.003 (3)0.004 (3)0.000 (3)
C140.030 (3)0.040 (4)0.017 (3)0.004 (3)0.004 (2)0.004 (3)
Geometric parameters (Å, º) top
N—C91.314 (8)C4—H40.9500
N—C101.453 (8)C5—C61.394 (9)
N—C141.495 (8)C6—H60.9500
O—C21.365 (7)C7—C81.344 (9)
O—H00.8400C10—C111.519 (10)
Br1—C31.883 (7)C10—H10A0.9900
Br2—C51.892 (6)C10—H10B0.9900
Br3—C81.876 (6)C11—C121.527 (10)
Br3—Br4i3.3063 (11)C11—H11A0.9900
S1—C91.723 (6)C11—H11B0.9900
S1—C81.737 (6)C12—C131.511 (11)
S2—C91.718 (6)C12—H12A0.9900
S2—C71.761 (6)C12—H12B0.9900
C1—C61.401 (8)C13—C141.518 (10)
C1—C21.412 (9)C13—H13A0.9900
C1—C71.472 (9)C13—H13B0.9900
C2—C31.375 (9)C14—H14A0.9900
C3—C41.385 (10)C14—H14B0.9900
C4—C51.380 (10)
C9—N—C10121.5 (5)N—C9—S1121.6 (5)
C9—N—C14121.4 (5)S2—C9—S1116.1 (4)
C10—N—C14115.7 (5)N—C10—C11110.5 (6)
C2—O—H0109.5N—C10—H10A109.6
C8—Br3—Br4i169.9 (2)C11—C10—H10A109.6
C9—S1—C894.7 (3)N—C10—H10B109.6
C9—S2—C795.7 (3)C11—C10—H10B109.6
C6—C1—C2119.9 (6)H10A—C10—H10B108.1
C6—C1—C7119.3 (6)C10—C11—C12109.6 (6)
C2—C1—C7120.8 (5)C10—C11—H11A109.7
O—C2—C3122.7 (6)C12—C11—H11A109.7
O—C2—C1118.1 (5)C10—C11—H11B109.7
C3—C2—C1119.2 (6)C12—C11—H11B109.7
C2—C3—C4121.5 (6)H11A—C11—H11B108.2
C2—C3—Br1119.2 (5)C13—C12—C11110.8 (6)
C4—C3—Br1119.2 (5)C13—C12—H12A109.5
C5—C4—C3119.1 (6)C11—C12—H12A109.5
C5—C4—H4120.4C13—C12—H12B109.5
C3—C4—H4120.4C11—C12—H12B109.5
C4—C5—C6121.5 (6)H12A—C12—H12B108.1
C4—C5—Br2118.3 (5)C12—C13—C14112.2 (6)
C6—C5—Br2120.2 (5)C12—C13—H13A109.2
C5—C6—C1118.8 (6)C14—C13—H13A109.2
C5—C6—H6120.6C12—C13—H13B109.2
C1—C6—H6120.6C14—C13—H13B109.2
C8—C7—C1127.4 (6)H13A—C13—H13B107.9
C8—C7—S2114.9 (5)N—C14—C13111.2 (6)
C1—C7—S2117.7 (5)N—C14—H14A109.4
C7—C8—S1118.7 (5)C13—C14—H14A109.4
C7—C8—Br3126.2 (5)N—C14—H14B109.4
S1—C8—Br3114.7 (4)C13—C14—H14B109.4
N—C9—S2122.3 (5)H14A—C14—H14B108.0
C6—C1—C2—O178.5 (6)S2—C7—C8—S10.2 (8)
C7—C1—C2—O3.8 (9)C1—C7—C8—Br37.4 (11)
C6—C1—C2—C30.1 (10)S2—C7—C8—Br3172.4 (4)
C7—C1—C2—C3177.9 (6)C9—S1—C8—C70.8 (6)
O—C2—C3—C4178.4 (6)C9—S1—C8—Br3172.3 (4)
C1—C2—C3—C40.1 (10)Br4i—Br3—C8—C787.8 (13)
O—C2—C3—Br11.3 (9)Br4i—Br3—C8—S184.7 (12)
C1—C2—C3—Br1179.6 (5)C10—N—C9—S2175.4 (6)
C2—C3—C4—C50.3 (11)C14—N—C9—S29.5 (10)
Br1—C3—C4—C5179.4 (5)C10—N—C9—S12.5 (10)
C3—C4—C5—C60.5 (11)C14—N—C9—S1168.4 (6)
C3—C4—C5—Br2179.3 (5)C7—S2—C9—N176.5 (6)
C4—C5—C6—C10.6 (11)C7—S2—C9—S11.5 (5)
Br2—C5—C6—C1179.2 (5)C8—S1—C9—N176.6 (6)
C2—C1—C6—C50.4 (10)C8—S1—C9—S21.4 (5)
C7—C1—C6—C5178.1 (6)C9—N—C10—C11138.2 (7)
C6—C1—C7—C847.4 (10)C14—N—C10—C1155.1 (8)
C2—C1—C7—C8134.8 (8)N—C10—C11—C1257.3 (8)
C6—C1—C7—S2132.8 (6)C10—C11—C12—C1357.8 (9)
C2—C1—C7—S244.9 (8)C11—C12—C13—C1454.4 (9)
C9—S2—C7—C81.0 (6)C9—N—C14—C13142.7 (7)
C9—S2—C7—C1178.8 (5)C10—N—C14—C1350.6 (9)
C1—C7—C8—S1179.6 (6)C12—C13—C14—N49.1 (8)
Symmetry code: (i) x+1, y1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O—H0···Br40.842.303.120 (5)167
C6—H6···Oii0.952.563.424 (8)151
C10—H10A···S10.992.462.985 (7)113
C13—H13A···Br2ii0.992.883.836 (7)163
C14—H14B···S20.992.513.026 (7)112
Symmetry code: (ii) x+1, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC14H13Br3NOS2+·Br
Mr595.01
Crystal system, space groupMonoclinic, P21/c
Temperature (K)153
a, b, c (Å)10.484 (2), 7.9240 (16), 21.396 (4)
β (°) 95.16 (3)
V3)1770.4 (6)
Z4
Radiation typeMo Kα
µ (mm1)9.33
Crystal size (mm)0.26 × 0.13 × 0.05
Data collection
DiffractometerStoe IPDS 2T area-detector
diffractometer
Absorption correctionFor a sphere
[modified Dwiggins (1975)]
Tmin, Tmax0.047, 0.073
No. of measured, independent and
observed [I > 2σ(I)] reflections
19422, 4399, 3413
Rint0.132
(sin θ/λ)max1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.061, 0.137, 1.08
No. of reflections4399
No. of parameters200
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)1.52, 1.03

Computer programs: X-AREA (Stoe & Cie, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O—H0···Br40.842.303.120 (5)167
 

Acknowledgements

Part of this work was supported by a grant of the Romanian National Authority for Scientific Research, CNDI– UEFISCDI, project No. 51/2012.

References

First citationBirsa, M. L. & Ganju, D. (2003). J. Phys. Org. Chem. 16, 207–212.  Web of Science CrossRef CAS
First citationBryce, M. R. (2000). J. Mater. Chem. 10, 589–598.  Web of Science CrossRef CAS
First citationDwiggins, C. W. (1975). Acta Cryst. A31, 146–148.  CrossRef IUCr Journals Web of Science
First citationFrasch, M., Mono, S., Pritzkow, H. & Sundermeyer, W. (1993). Chem. Ber. 126, 273–275.  CrossRef CAS Web of Science
First citationNarita, M. & Pittman, C. U. Jr (1976). Synthesis, pp. 489–514.  CrossRef Web of Science
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals
First citationStoe & Cie (2002). X-AREA. Stoe & Cie, Darmstadt, Germany.

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