PMCCPMCCPMCC

Search tips
Search criteria 

Advanced

 
Logo of actaeInternational Union of Crystallographysearchopen accessarticle submissionjournal home pagethis article
 
Acta Crystallogr Sect E Struct Rep Online. 2009 February 1; 65(Pt 2): o410.
Published online 2009 January 28. doi:  10.1107/S1600536809002943
PMCID: PMC2968282

2-{1-[2-((2-Ammonio­ethyl){2-[1-(5-chloro-2-hydroxy­phen­yl)ethyl­idene­amino]eth­yl}amino)ethyl­iminio]eth­yl}-4-chloro­phenolate trifluoro­acetate

Abstract

In the title ion-pair, C22H29Cl2N4O2 +·C2F3O2 , ammonium–carboxyl­ate N—H(...)O hydrogen bonds link two cations and two anions about a centre of inversion to generate a hydrogen-bonded tetramer. In the cation, one of the imino N atoms is protonated and donates a hydrogen bond to the O atom of the adjacent chloro­phenyl ring. The other imino N atom acts as a hydrogen-bond acceptor from a phenolate O atom.

Related literature

The precursor Schiff base, bis­{2-[1-(5-chloro-2-hydroxyphenyl)ethyl­eneamino]eth­yl}{2-[1-(5-chloro-2-phenolate)ethyl­ene­aminio]eth­yl}amine, has one of the three C=N double bonds protonated on the N atom (Lee et al., 2009 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-0o410-scheme1.jpg

Experimental

Crystal data

  • C22H29Cl2N4O2 +·C2F3O2
  • M r = 565.41
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-0o410-efi1.jpg
  • a = 10.1041 (2) Å
  • b = 10.6788 (2) Å
  • c = 12.5241 (3) Å
  • α = 88.386 (1)°
  • β = 70.743 (1)°
  • γ = 81.234 (2)°
  • V = 1260.48 (5) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.32 mm−1
  • T = 100 (2) K
  • 0.06 × 0.04 × 0.02 mm

Data collection

  • Bruker SMART APEX diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.981, T max = 0.994
  • 12201 measured reflections
  • 5762 independent reflections
  • 4104 reflections with I > 2σ(I)
  • R int = 0.032

Refinement

  • R[F 2 > 2σ(F 2)] = 0.048
  • wR(F 2) = 0.126
  • S = 1.03
  • 5762 reflections
  • 356 parameters
  • 5 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.72 e Å−3
  • Δρmin = −0.46 e Å−3

Data collection: APEX2 (Bruker, 2007 [triangle]); cell refinement: SAINT (Bruker, 2007 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: X-SEED (Barbour, 2001 [triangle]); software used to prepare material for publication: publCIF (Westrip, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809002943/bt2856sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809002943/bt2856Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors thank the University of Malaya (grant Nos. FS339/2008A and PS072/2007C) for supporting this study.

supplementary crystallographic information

Experimental

Tris(2-aminoethyl)amine (1.46 g m 10 mmol) was condensed with 5-chloro-2-hydroxyacetophenone (5.12 g, 30 mol) in refluxing ethanol (100 ml) to yield the unsolvated Schiff base. The compound (0.64 g, 1 mmol) and trifluoroacetic acid (0.11 g, 1 mmol) were dissolved in a small volume of ethanol. Crystals of the salt separated after several days.

Refinement

Carbon-bound H atoms were placed in calculated positions (C—H = 0.93–0.99 Å) and were included in the refinement in the riding model approximation, with U(H) set to 1.2 to 1.5U(C). The methyl H atoms were rotated to fit the electron density.

The iminium/ammonium and hydroxy H atoms were located in a difference Fourier map, and were refined with distance restraints [N—H = 0.88 (1) and O—H = 0.84 (1) Å; their isotropic displacement parameters were freely refined.

Figures

Fig. 1.
Anisotropic displacement ellipsoid plot (Barbour, 2001) of the title compound at the 70% probability level. H atoms are drawn as spheres of arbitrary radius.

Crystal data

C22H29Cl2N4O2+·C2F3O2Z = 2
Mr = 565.41F(000) = 588
Triclinic, P1Dx = 1.490 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 10.1041 (2) ÅCell parameters from 2402 reflections
b = 10.6788 (2) Åθ = 2.2–27.8°
c = 12.5241 (3) ŵ = 0.32 mm1
α = 88.386 (1)°T = 100 K
β = 70.743 (1)°Prism, yellow
γ = 81.234 (2)°0.06 × 0.04 × 0.02 mm
V = 1260.48 (5) Å3

Data collection

Bruker SMART APEX diffractometer5762 independent reflections
Radiation source: fine-focus sealed tube4104 reflections with I > 2σ(I)
graphiteRint = 0.032
ω scansθmax = 27.5°, θmin = 1.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −13→13
Tmin = 0.981, Tmax = 0.994k = −13→13
12201 measured reflectionsl = −16→16

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.126H atoms treated by a mixture of independent and constrained refinement
S = 1.02w = 1/[σ2(Fo2) + (0.0533P)2 + 0.6261P] where P = (Fo2 + 2Fc2)/3
5762 reflections(Δ/σ)max = 0.001
356 parametersΔρmax = 0.72 e Å3
5 restraintsΔρmin = −0.46 e Å3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

xyzUiso*/Ueq
Cl10.10326 (7)0.47757 (6)1.36535 (5)0.03022 (16)
Cl20.46582 (7)0.29988 (6)1.26264 (5)0.03337 (17)
O10.24624 (17)0.42151 (15)0.87521 (13)0.0261 (4)
O20.22931 (18)−0.00604 (16)1.01009 (14)0.0258 (4)
H210.278 (4)0.005 (4)0.9419 (14)0.092 (14)*
O30.6309 (2)0.30567 (19)0.55587 (16)0.0445 (5)
O40.7436 (2)0.30693 (16)0.36975 (14)0.0349 (4)
N10.0653 (2)0.27355 (18)0.90939 (15)0.0203 (4)
H110.135 (2)0.316 (2)0.871 (2)0.042 (8)*
N20.39560 (19)0.06404 (17)0.83106 (15)0.0214 (4)
N30.23242 (19)0.19477 (17)0.68450 (15)0.0207 (4)
N40.3612 (2)0.4419 (2)0.64538 (17)0.0242 (4)
H410.332 (3)0.425 (2)0.7177 (10)0.027 (7)*
H420.4511 (14)0.408 (2)0.613 (2)0.044 (8)*
H430.353 (3)0.5260 (10)0.641 (2)0.038 (8)*
C10.2076 (2)0.4375 (2)0.98379 (18)0.0200 (5)
C20.0963 (2)0.37800 (19)1.06063 (18)0.0177 (4)
C30.0633 (2)0.3952 (2)1.17817 (18)0.0193 (5)
H3−0.01130.35691.22900.023*
C40.1376 (2)0.4664 (2)1.21953 (18)0.0216 (5)
C50.2434 (2)0.5277 (2)1.1471 (2)0.0247 (5)
H50.29250.57871.17730.030*
C60.2769 (2)0.5144 (2)1.0326 (2)0.0246 (5)
H60.34850.55780.98420.030*
C70.0240 (2)0.2942 (2)1.01801 (18)0.0179 (4)
C8−0.0912 (2)0.2298 (2)1.09553 (19)0.0250 (5)
H8A−0.12620.17731.05090.037*
H8B−0.16920.29381.13940.037*
H8C−0.05390.17631.14710.037*
C90.0156 (2)0.1860 (2)0.84896 (19)0.0227 (5)
H9A−0.08930.20160.87300.027*
H9B0.04580.09760.86680.027*
C100.0773 (2)0.2056 (2)0.72269 (19)0.0231 (5)
H10A0.04990.14180.68140.028*
H10B0.03680.29060.70440.028*
C110.3915 (2)0.1380 (2)1.00730 (18)0.0193 (5)
C120.4442 (2)0.2098 (2)1.07147 (19)0.0214 (5)
H120.51830.25691.03420.026*
C130.3905 (2)0.2132 (2)1.18738 (19)0.0222 (5)
C140.2819 (2)0.1461 (2)1.24520 (19)0.0237 (5)
H140.24420.15031.32550.028*
C150.2300 (2)0.0732 (2)1.18385 (19)0.0224 (5)
H150.15650.02611.22270.027*
C160.2827 (2)0.0670 (2)1.06586 (19)0.0208 (5)
C170.4476 (2)0.1367 (2)0.88267 (19)0.0214 (5)
C180.5569 (3)0.2198 (2)0.8265 (2)0.0273 (5)
H18A0.58910.20510.74440.041*
H18B0.63770.19950.85400.041*
H18C0.51520.30890.84430.041*
C190.4354 (3)0.0499 (2)0.70858 (19)0.0259 (5)
H19A0.4932−0.03410.68330.031*
H19B0.49270.11590.67110.031*
C200.3015 (2)0.0623 (2)0.6765 (2)0.0247 (5)
H20A0.32580.02950.59810.030*
H20B0.23470.01040.72730.030*
C210.2872 (3)0.2563 (2)0.57570 (19)0.0266 (5)
H21A0.23680.23400.52490.032*
H21B0.38890.22230.54040.032*
C220.2712 (3)0.3986 (2)0.5850 (2)0.0274 (5)
H22A0.29680.43360.50810.033*
H22B0.17060.43250.62560.033*
C230.7267 (2)0.2710 (2)0.4670 (2)0.0245 (5)
C240.8459 (3)0.1700 (2)0.4815 (2)0.0281 (5)
F10.79561 (19)0.07794 (17)0.54812 (16)0.0644 (6)
F20.9303 (2)0.21998 (18)0.5210 (2)0.0813 (8)
F30.92729 (18)0.11073 (17)0.38502 (15)0.0550 (5)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Cl10.0342 (3)0.0384 (4)0.0199 (3)0.0023 (3)−0.0144 (3)−0.0062 (2)
Cl20.0386 (4)0.0377 (4)0.0288 (3)−0.0110 (3)−0.0150 (3)−0.0050 (3)
O10.0300 (9)0.0305 (9)0.0170 (8)−0.0130 (7)−0.0031 (7)0.0024 (7)
O20.0267 (9)0.0292 (9)0.0234 (9)−0.0125 (7)−0.0069 (8)0.0015 (7)
O30.0322 (10)0.0547 (13)0.0297 (10)0.0114 (9)0.0037 (8)0.0106 (9)
O40.0475 (11)0.0331 (10)0.0223 (9)−0.0028 (8)−0.0111 (8)0.0062 (7)
N10.0228 (10)0.0221 (10)0.0169 (9)−0.0087 (8)−0.0054 (8)−0.0002 (7)
N20.0216 (10)0.0239 (10)0.0186 (9)−0.0002 (8)−0.0078 (8)0.0011 (8)
N30.0235 (10)0.0230 (10)0.0149 (9)−0.0012 (8)−0.0065 (8)−0.0002 (7)
N40.0251 (11)0.0292 (12)0.0153 (10)−0.0029 (9)−0.0034 (9)0.0054 (8)
C10.0233 (11)0.0173 (11)0.0197 (11)−0.0029 (9)−0.0076 (9)0.0027 (8)
C20.0183 (11)0.0156 (10)0.0199 (11)−0.0020 (8)−0.0075 (9)0.0006 (8)
C30.0202 (11)0.0190 (11)0.0165 (11)0.0015 (9)−0.0050 (9)0.0007 (8)
C40.0269 (12)0.0216 (11)0.0174 (11)0.0016 (9)−0.0110 (10)−0.0022 (9)
C50.0286 (12)0.0202 (12)0.0312 (13)−0.0046 (9)−0.0170 (11)−0.0014 (9)
C60.0268 (12)0.0207 (12)0.0282 (13)−0.0095 (9)−0.0094 (10)0.0035 (9)
C70.0191 (11)0.0159 (10)0.0186 (11)−0.0005 (8)−0.0071 (9)0.0003 (8)
C80.0282 (12)0.0281 (13)0.0196 (11)−0.0121 (10)−0.0058 (10)0.0021 (9)
C90.0248 (12)0.0242 (12)0.0215 (11)−0.0074 (9)−0.0088 (10)−0.0031 (9)
C100.0271 (12)0.0241 (12)0.0203 (11)−0.0028 (9)−0.0110 (10)−0.0021 (9)
C110.0205 (11)0.0179 (11)0.0191 (11)−0.0013 (9)−0.0067 (9)0.0018 (8)
C120.0200 (11)0.0190 (11)0.0255 (12)−0.0039 (9)−0.0075 (10)0.0032 (9)
C130.0236 (12)0.0211 (12)0.0237 (12)−0.0011 (9)−0.0108 (10)−0.0017 (9)
C140.0245 (12)0.0256 (12)0.0179 (11)0.0009 (9)−0.0050 (9)0.0011 (9)
C150.0200 (11)0.0212 (11)0.0231 (12)−0.0034 (9)−0.0033 (9)0.0034 (9)
C160.0179 (11)0.0207 (11)0.0234 (12)−0.0015 (9)−0.0069 (9)0.0012 (9)
C170.0192 (11)0.0199 (11)0.0251 (12)−0.0013 (9)−0.0083 (10)0.0029 (9)
C180.0277 (13)0.0311 (13)0.0216 (12)−0.0091 (10)−0.0046 (10)0.0049 (10)
C190.0283 (13)0.0291 (13)0.0182 (11)0.0023 (10)−0.0075 (10)−0.0010 (9)
C200.0302 (13)0.0238 (12)0.0209 (12)−0.0009 (10)−0.0106 (10)−0.0035 (9)
C210.0310 (13)0.0331 (13)0.0150 (11)−0.0018 (10)−0.0078 (10)0.0008 (9)
C220.0313 (13)0.0306 (13)0.0209 (12)−0.0048 (10)−0.0097 (10)0.0075 (10)
C230.0244 (12)0.0243 (12)0.0239 (12)−0.0046 (9)−0.0069 (10)0.0038 (9)
C240.0271 (13)0.0301 (13)0.0257 (13)−0.0042 (10)−0.0072 (11)0.0029 (10)
F10.0543 (11)0.0495 (11)0.0659 (13)0.0096 (9)0.0014 (10)0.0328 (10)
F20.0898 (15)0.0505 (12)0.143 (2)0.0103 (10)−0.0980 (16)−0.0211 (12)
F30.0445 (10)0.0601 (12)0.0440 (10)0.0166 (8)−0.0026 (8)−0.0095 (8)

Geometric parameters (Å, °)

Cl1—C41.747 (2)C9—C101.518 (3)
Cl2—C131.749 (2)C9—H9A0.9900
O1—C11.294 (3)C9—H9B0.9900
O2—C161.339 (3)C10—H10A0.9900
O2—H210.847 (10)C10—H10B0.9900
O3—C231.231 (3)C11—C121.400 (3)
O4—C231.231 (3)C11—C161.419 (3)
N1—C71.299 (3)C11—C171.474 (3)
N1—C91.460 (3)C12—C131.371 (3)
N1—H110.889 (10)C12—H120.9500
N2—C171.293 (3)C13—C141.389 (3)
N2—C191.458 (3)C14—C151.377 (3)
N3—C101.467 (3)C14—H140.9500
N3—C201.469 (3)C15—C161.396 (3)
N3—C211.469 (3)C15—H150.9500
N4—C221.487 (3)C17—C181.501 (3)
N4—H410.878 (10)C18—H18A0.9800
N4—H420.886 (10)C18—H18B0.9800
N4—H430.892 (10)C18—H18C0.9800
C1—C61.423 (3)C19—C201.520 (3)
C1—C21.436 (3)C19—H19A0.9900
C2—C31.409 (3)C19—H19B0.9900
C2—C71.450 (3)C20—H20A0.9900
C3—C41.365 (3)C20—H20B0.9900
C3—H30.9500C21—C221.507 (3)
C4—C51.391 (3)C21—H21A0.9900
C5—C61.367 (3)C21—H21B0.9900
C5—H50.9500C22—H22A0.9900
C6—H60.9500C22—H22B0.9900
C7—C81.494 (3)C23—C241.545 (3)
C8—H8A0.9800C24—F21.299 (3)
C8—H8B0.9800C24—F11.322 (3)
C8—H8C0.9800C24—F31.329 (3)
C16—O2—H21102 (3)C13—C12—H12119.5
C7—N1—C9127.14 (19)C11—C12—H12119.5
C7—N1—H11113.5 (19)C12—C13—C14121.3 (2)
C9—N1—H11119.3 (19)C12—C13—Cl2118.69 (18)
C17—N2—C19124.9 (2)C14—C13—Cl2119.96 (18)
C10—N3—C20112.17 (18)C15—C14—C13118.7 (2)
C10—N3—C21111.60 (18)C15—C14—H14120.7
C20—N3—C21109.93 (18)C13—C14—H14120.7
C22—N4—H41112.4 (17)C14—C15—C16121.5 (2)
C22—N4—H42110.4 (19)C14—C15—H15119.2
H41—N4—H42110 (3)C16—C15—H15119.2
C22—N4—H43107.7 (18)O2—C16—C15119.2 (2)
H41—N4—H43106 (2)O2—C16—C11121.3 (2)
H42—N4—H43109 (3)C15—C16—C11119.5 (2)
O1—C1—C6120.6 (2)N2—C17—C11116.1 (2)
O1—C1—C2122.6 (2)N2—C17—C18125.6 (2)
C6—C1—C2116.8 (2)C11—C17—C18118.3 (2)
C3—C2—C1119.7 (2)C17—C18—H18A109.5
C3—C2—C7119.8 (2)C17—C18—H18B109.5
C1—C2—C7120.32 (19)H18A—C18—H18B109.5
C4—C3—C2120.5 (2)C17—C18—H18C109.5
C4—C3—H3119.8H18A—C18—H18C109.5
C2—C3—H3119.8H18B—C18—H18C109.5
C3—C4—C5121.0 (2)N2—C19—C20108.94 (19)
C3—C4—Cl1119.76 (18)N2—C19—H19A109.9
C5—C4—Cl1119.19 (17)C20—C19—H19A109.9
C6—C5—C4120.0 (2)N2—C19—H19B109.9
C6—C5—H5120.0C20—C19—H19B109.9
C4—C5—H5120.0H19A—C19—H19B108.3
C5—C6—C1121.9 (2)N3—C20—C19111.49 (19)
C5—C6—H6119.0N3—C20—H20A109.3
C1—C6—H6119.0C19—C20—H20A109.3
N1—C7—C2117.78 (19)N3—C20—H20B109.3
N1—C7—C8120.4 (2)C19—C20—H20B109.3
C2—C7—C8121.75 (19)H20A—C20—H20B108.0
C7—C8—H8A109.5N3—C21—C22114.00 (19)
C7—C8—H8B109.5N3—C21—H21A108.8
H8A—C8—H8B109.5C22—C21—H21A108.8
C7—C8—H8C109.5N3—C21—H21B108.8
H8A—C8—H8C109.5C22—C21—H21B108.8
H8B—C8—H8C109.5H21A—C21—H21B107.6
N1—C9—C10109.14 (18)N4—C22—C21112.88 (19)
N1—C9—H9A109.9N4—C22—H22A109.0
C10—C9—H9A109.9C21—C22—H22A109.0
N1—C9—H9B109.9N4—C22—H22B109.0
C10—C9—H9B109.9C21—C22—H22B109.0
H9A—C9—H9B108.3H22A—C22—H22B107.8
N3—C10—C9112.01 (18)O3—C23—O4130.0 (2)
N3—C10—H10A109.2O3—C23—C24114.3 (2)
C9—C10—H10A109.2O4—C23—C24115.6 (2)
N3—C10—H10B109.2F2—C24—F1109.2 (2)
C9—C10—H10B109.2F2—C24—F3106.2 (2)
H10A—C10—H10B107.9F1—C24—F3104.2 (2)
C12—C11—C16118.0 (2)F2—C24—C23111.5 (2)
C12—C11—C17120.8 (2)F1—C24—C23112.3 (2)
C16—C11—C17121.2 (2)F3—C24—C23113.1 (2)
C13—C12—C11121.0 (2)
O1—C1—C2—C3177.41 (19)Cl2—C13—C14—C15−176.52 (17)
C6—C1—C2—C3−1.5 (3)C13—C14—C15—C16−0.8 (3)
O1—C1—C2—C71.2 (3)C14—C15—C16—O2179.5 (2)
C6—C1—C2—C7−177.62 (19)C14—C15—C16—C11−0.6 (3)
C1—C2—C3—C4−1.0 (3)C12—C11—C16—O2−178.6 (2)
C7—C2—C3—C4175.23 (19)C17—C11—C16—O21.6 (3)
C2—C3—C4—C52.6 (3)C12—C11—C16—C151.5 (3)
C2—C3—C4—Cl1−175.57 (16)C17—C11—C16—C15−178.3 (2)
C3—C4—C5—C6−1.7 (3)C19—N2—C17—C11179.43 (19)
Cl1—C4—C5—C6176.49 (18)C19—N2—C17—C180.4 (4)
C4—C5—C6—C1−0.9 (4)C12—C11—C17—N2177.7 (2)
O1—C1—C6—C5−176.5 (2)C16—C11—C17—N2−2.5 (3)
C2—C1—C6—C52.4 (3)C12—C11—C17—C18−3.2 (3)
C9—N1—C7—C2175.0 (2)C16—C11—C17—C18176.6 (2)
C9—N1—C7—C8−3.1 (3)C17—N2—C19—C20−131.8 (2)
C3—C2—C7—N1−174.86 (19)C10—N3—C20—C19−145.03 (19)
C1—C2—C7—N11.3 (3)C21—N3—C20—C1990.2 (2)
C3—C2—C7—C83.3 (3)N2—C19—C20—N374.7 (2)
C1—C2—C7—C8179.4 (2)C10—N3—C21—C2278.2 (2)
C7—N1—C9—C10172.3 (2)C20—N3—C21—C22−156.73 (19)
C20—N3—C10—C976.3 (2)N3—C21—C22—N467.2 (3)
C21—N3—C10—C9−159.79 (18)O3—C23—C24—F2−76.8 (3)
N1—C9—C10—N354.4 (2)O4—C23—C24—F2101.3 (3)
C16—C11—C12—C13−1.1 (3)O3—C23—C24—F146.1 (3)
C17—C11—C12—C13178.72 (19)O4—C23—C24—F1−135.8 (2)
C11—C12—C13—C14−0.2 (3)O3—C23—C24—F3163.6 (2)
C11—C12—C13—Cl2177.53 (17)O4—C23—C24—F3−18.3 (3)
C12—C13—C14—C151.2 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O2—H21···N20.85 (1)1.68 (2)2.493 (2)159 (4)
N1—H11···O10.89 (1)1.73 (2)2.520 (2)147 (3)
N4—H41···O10.88 (1)1.88 (1)2.742 (2)168 (2)
N4—H42···O30.89 (1)1.89 (1)2.769 (3)169 (3)
N4—H43···O4i0.89 (1)1.92 (2)2.755 (3)154 (3)

Symmetry codes: (i) −x+1, −y+1, −z+1.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BT2856).

References

  • Barbour, L. J. (2001). J. Supramol. Chem.1, 189–191.
  • Bruker (2007). APEX2 and SAINT Bruker AXS Inc., Madison, Wisconsin, USA.
  • Lee, S. M., Ali, H. M., Lo, K. M. & Ng, S. W. (2009). Acta Cryst. E65, o409. [PMC free article] [PubMed]
  • Sheldrick, G. M. (1996). SADABS University of Göttingen, Germany.
  • Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. [PubMed]
  • Westrip, S. P. (2009). publCIF In preparation.

Articles from Acta Crystallographica Section E: Structure Reports Online are provided here courtesy of International Union of Crystallography