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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

(E)-4-(4-Fluoro­styr­yl)benzoic acid

aDepartment of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan, and bDepartment of Chemistry, Faculty of Engineering, Gifu University, Yanagido, Gifu 501-1193, Japan
*Correspondence e-mail: shameed@qau.edu.pk

(Received 30 April 2008; accepted 1 May 2008; online 7 May 2008)

The title compound, C15H11FO2, is an important inter­mediate in the synthesis of side-chain ligands for polymeric liquid crystals. The vinyl group is almost coplanar with both the aromatic rings. The crystal structure is stabilized by inter­molecular O—H⋯O hydrogen bonding.

Related literature

For related literature, see: Ahmad et al. (2003[Ahmad, H. B., Rama, N. H., Hussain, M., Hussain, M. T., Qasim, M. M., Hameed, S., Malana, M. A. & Malik, A. (2003). Indian J. Chem. B42, 611-615.]); Collings & Hird (1997[Collings, P. J. & Hird, M. (1997). Introduction to Liquid Crystals, Chemistry and Physics, edited by G. W. Gray, J. W. Goodby & A. Fukuda, pp. 43-78. Bristol: Taylor and Francis.]); Frazee & Foraker (2008[Frazee, L. A. & Foraker, K. C. (2008). Annals Pharmacother. 42, 403-407.]); Hameed & Rama (2004[Hameed, S. & Rama, N. H. (2004). J. Chem. Soc. Pak. 26, 157-162.]); Hussain et al. (2005[Hussain, M. T., Rama, N. H., Hameed, S., Malik, A. & Khan, K. M. (2005). Nat. Prod. Res. 19, 41-51.]); Nazir et al. (2008[Nazir, S., Khawar Rauf, M., Ebihara, M. & Hameed, S. (2008). Acta Cryst. E64, o423.]); Ribeiro et al. (2008[Ribeiro, G., Benadiba, M., Colquhoun, A. & Silva, D. D. (2008). Polyhedron, 27, 1131-1137.]); Wang et al. (2008[Wang, M. L., Liu, B. L. & Lin, S. J. (2008). Chem. Eng. Commun. 195, 770-786.]); Higashi (1999[Higashi, T. (1999). NUMABS. Rigaku Corporation, 3-9-12 Akishima, Tokyo 196-8666, Japan.]); Yasuda et al. (2000[Yasuda, N., Uekusa, H. & Ohashi, Y. (2000). Acta Cryst. C56, 1364-1366.]).

[Scheme 1]

Experimental

Crystal data
  • C15H11FO2

  • Mr = 242.24

  • Monoclinic, P 21 /c

  • a = 6.261 (4) Å

  • b = 23.096 (15) Å

  • c = 8.269 (5) Å

  • β = 107.072 (8)°

  • V = 1143.1 (13) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 123 (2) K

  • 0.45 × 0.30 × 0.18 mm

Data collection
  • Rigaku/MSC Mercury CCD diffractometer

  • Absorption correction: none

  • 9111 measured reflections

  • 2589 independent reflections

  • 2399 reflections with I > 2σ(I)

  • Rint = 0.036

Refinement
  • R[F2 > 2σ(F2)] = 0.065

  • wR(F2) = 0.155

  • S = 1.16

  • 2589 reflections

  • 167 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.55 e Å−3

  • Δρmin = −0.28 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2⋯O1i 1.04 (4) 1.57 (4) 2.610 (2) 174 (3)
Symmetry code: (i) -x+2, -y, -z+2.

Data collection: CrystalClear (MSC/Rigaku, 2001[MSC/Rigaku (2001). CrystalClear. MSC/Rigaku, The Woodlands, Texas, USA.]); cell refinement: CrystalClear; data reduction: TEXSAN (MSC/Rigaku, 2004[MSC/Rigaku (2004). TEXSAN. MSC/Rigaku, The Woodlands, Texas, USA.]); program(s) used to solve structure: SIR97 (Altomare et al., 1999[Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115-119.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEPII (Johnson, 1976[Johnson, C. K. (1976). ORTEPII. Report ORNL-5138. Oak Ridge National Laboratory, Tennessee, USA.]); software used to prepare material for publication: SHELXL97 and TEXSAN.

Supporting information


Comment top

Carboxylic acids constitute an important class of organic compounds and have been used by the medicinal industry as important drugs (Ribeiro et al., 2008; Frazee & Foraker 2008; Hameed & Rama 2004). The carboxylic acids have also found applications as intermediates in the synthesis of an enormous number of organic compounds, in general (Hussain et al., 2005; Ahmad et al., 2003), and in the synthesis of side chain ligands for polymeric liquid crystals, in particular (Wang et al., 2008; Nazir et al., 2008). The liquid crystalline molecules containing substituents at 4-position behave as well ordered calamitic ligands as a side chain group (Collings & Hird, 1997) in side chain polymeric liquid crysrtals (SCPLCs). The derivatives of 4-(4-substituted styryl)benzoic acids have found applications as side chain groups in SCPLCs (Wang et al., 2008). As a part of a project to synthesize ligands for SCPLCs, the title compound, (E)-4-(4-fluorostyryl)benzoic acid (I), was synthesized by reacting 4-fluorobenzaldehyde with methyl [4-(methoxycarbonyl)benzyl]triphenylphosphonium bromide (Nazir et al., 2008) followed by hydrolysis. In the present article, the crystal structure of (I) is being reported. Bond lengths and angles are within the normal ranges as given for vinylbenzoic acid (Yasuda et al., 2000). The C(1)—O(1) and C(1)—O(2) bond lengths are 1.252 (2) and 1.291 (2) respectively,clearly indicating the partial double bond character of the carboxylate group. The carboxylic acid group subtends a dihedral angle[13.72 (16)°] with the phenyl ring C(2)/C(3)/C(4)/C(5)/C(6)/C(7).The vinyl group is almost coplanar with both the phenyl rings. The torsion angles between the phenyl rings and vinyl group fulfill the condition of coplanarity[near to 0° or 180 °]. Two molecules related by an inversion center form a dimer via two hydrogen bonds composed of two carboxyl groups as shown in Fig. 2.

Related literature top

For related literature, see: Ahmad et al. (2003); Collings & Hird (1997); Frazee & Foraker (2008); Hameed & Rama (2004); Hussain et al. (2005); Nazir et al. (2008); Ribeiro et al. (2008); Wang et al. (2008); Higashi (1999); Yasuda et al. (2000).

Experimental top

Methyl 4-(4-fluorostyryl)benzoate 0.8g (0.0031moles) and sodium hydroxide 0.126g (0.0031 moles) were dissolved in a mixture of 10 ml of methanol and 30 ml of water, and the mixture refluxed for 3 hours. The reaction mixture was cooled to room temperature and acidified with 6M HCl. The precipitated solid was filtered and recrystallized from hot ethanol. Yield: 76%, m.p: 240-252°C, Rf = 0.22 (n-hexane : ethyl acetate 7 : 3). IR (νmax, KBr, cm-1): 3300-2500, 1715, 1620, 1600, 1580, 1188, 1119, 965,834. 1H-NMR (300 MHz,DMSO-d6): δ 7.25 (2H, d, J = 9.0 Hz),7.28 (1H, d, J= 16.2 Hz), 7.42 (1H, d, J = 16.2 Hz), 7.71-7.67 (4H, m),7.95 (2H, d, J = 8.1 Hz), 12.93 (1H, s). 13C-NMR (75 MHz, DMSO-d6): δ 116.16 (d, J= 23 Hz), 126.90, 127.77, 129.23, 130.08 (d, J = 8 Hz), 131.95, 132.49, 133.71 (d, J = 3 Hz), 141.83, 162.42 (d, J = 246 Hz), 167.54.

Refinement top

The O-bound H atom was refined isotropically. All the other H atoms were placed in idealized positions and treated as riding atoms with C—H distance in the range 0.95–0.99 Å and Uiso(H) = 1.2Ueq(C) or 1.5Ueq(C).

Computing details top

Data collection: CrystalClear (MSC/Rigaku, 2001); cell refinement: CrystalClear (MSC/Rigaku, 2001); data reduction: TEXSAN (MSC/Rigaku , 2004); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and TEXSAN (MSC/Rigaku, 2004).

Figures top
[Figure 1] Fig. 1. Molecular structure of (I) showing atom-labelling scheme and displacement ellipsoids at the 30% probability level.
[Figure 2] Fig. 2. Showing hydrogen bonded molecules through N—H···O.
(E)-4-(4-Fluorostyryl)benzoic acid top
Crystal data top
C15H11FO2F(000) = 504
Mr = 242.24Dx = 1.408 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71070 Å
Hall symbol: -P 2ybcCell parameters from 3252 reflections
a = 6.261 (4) Åθ = 3.1–27.5°
b = 23.096 (15) ŵ = 0.10 mm1
c = 8.269 (5) ÅT = 123 K
β = 107.072 (8)°Needle, colourless
V = 1143.1 (13) Å30.45 × 0.30 × 0.18 mm
Z = 4
Data collection top
Rigaku/MSC Mercury CCD
diffractometer
2399 reflections with I > 2σ(I)
Radiation source: Rotating anodeRint = 0.036
Graphite monochromatorθmax = 27.5°, θmin = 3.1°
ω scansh = 86
9111 measured reflectionsk = 2529
2589 independent reflectionsl = 109
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)] = 0.065Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.155H atoms treated by a mixture of independent and constrained refinement
S = 1.16 w = 1/[σ2(Fo2) + (0.0616P)2 + 0.7669P]
where P = (Fo2 + 2Fc2)/3
2589 reflections(Δ/σ)max < 0.001
167 parametersΔρmax = 0.55 e Å3
0 restraintsΔρmin = 0.28 e Å3
Crystal data top
C15H11FO2V = 1143.1 (13) Å3
Mr = 242.24Z = 4
Monoclinic, P21/cMo Kα radiation
a = 6.261 (4) ŵ = 0.10 mm1
b = 23.096 (15) ÅT = 123 K
c = 8.269 (5) Å0.45 × 0.30 × 0.18 mm
β = 107.072 (8)°
Data collection top
Rigaku/MSC Mercury CCD
diffractometer
2399 reflections with I > 2σ(I)
9111 measured reflectionsRint = 0.036
2589 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0650 restraints
wR(F2) = 0.155H atoms treated by a mixture of independent and constrained refinement
S = 1.16Δρmax = 0.55 e Å3
2589 reflectionsΔρmin = 0.28 e Å3
167 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
xyzUiso*/Ueq
C10.7742 (3)0.03235 (7)0.8139 (2)0.0188 (4)
O10.9748 (2)0.04569 (6)0.83715 (16)0.0268 (3)
O20.7095 (2)0.00358 (6)0.90952 (16)0.0258 (3)
H20.843 (6)0.0202 (16)1.006 (5)0.089 (12)*
C20.5982 (3)0.05820 (7)0.6720 (2)0.0188 (4)
C30.6547 (3)0.10173 (8)0.5755 (2)0.0221 (4)
H30.80540.11430.60020.027*
C40.4916 (3)0.12671 (8)0.4437 (2)0.0246 (4)
H40.53130.15680.37960.030*
C50.2699 (3)0.10851 (8)0.4031 (2)0.0231 (4)
C60.2149 (3)0.06476 (8)0.5012 (2)0.0232 (4)
H60.06450.05190.47560.028*
C70.3771 (3)0.03999 (8)0.6354 (2)0.0213 (4)
H70.33740.01070.70200.026*
C80.1067 (3)0.13727 (8)0.2605 (2)0.0250 (4)
H80.15860.16940.21110.030*
C90.1064 (3)0.12250 (8)0.1943 (2)0.0246 (4)
H90.15870.09040.24360.030*
C100.2687 (3)0.15134 (8)0.0517 (2)0.0224 (4)
C110.2127 (3)0.19609 (8)0.0431 (2)0.0250 (4)
H110.06280.20940.01480.030*
C120.3734 (3)0.22120 (8)0.1778 (2)0.0273 (4)
H120.33530.25140.24240.033*
C130.5900 (3)0.20104 (8)0.2150 (2)0.0262 (4)
C140.6531 (3)0.15774 (8)0.1256 (2)0.0257 (4)
H140.80400.14510.15390.031*
C150.4898 (3)0.13277 (8)0.0075 (2)0.0241 (4)
H150.53000.10230.07000.029*
F10.7470 (2)0.22525 (6)0.34838 (15)0.0419 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0185 (8)0.0204 (8)0.0175 (8)0.0011 (6)0.0052 (6)0.0007 (6)
O10.0173 (6)0.0346 (8)0.0269 (7)0.0001 (5)0.0040 (5)0.0061 (5)
O20.0227 (6)0.0285 (7)0.0251 (6)0.0005 (5)0.0053 (5)0.0084 (5)
C20.0190 (8)0.0200 (8)0.0165 (8)0.0030 (6)0.0038 (6)0.0018 (6)
C30.0213 (8)0.0251 (9)0.0195 (8)0.0016 (7)0.0054 (6)0.0001 (6)
C40.0267 (9)0.0253 (9)0.0219 (8)0.0031 (7)0.0073 (7)0.0034 (7)
C50.0246 (9)0.0249 (9)0.0175 (8)0.0057 (7)0.0029 (7)0.0022 (6)
C60.0175 (8)0.0265 (9)0.0237 (8)0.0019 (7)0.0032 (7)0.0034 (7)
C70.0196 (8)0.0226 (9)0.0211 (8)0.0012 (7)0.0052 (6)0.0003 (6)
C80.0238 (9)0.0262 (9)0.0234 (8)0.0025 (7)0.0045 (7)0.0031 (7)
C90.0264 (9)0.0248 (9)0.0221 (8)0.0011 (7)0.0062 (7)0.0004 (7)
C100.0220 (9)0.0243 (9)0.0187 (8)0.0044 (7)0.0028 (6)0.0041 (6)
C110.0216 (9)0.0259 (10)0.0265 (9)0.0002 (7)0.0055 (7)0.0057 (7)
C120.0347 (10)0.0217 (9)0.0265 (9)0.0025 (8)0.0104 (8)0.0006 (7)
C130.0280 (9)0.0233 (9)0.0215 (8)0.0116 (7)0.0018 (7)0.0012 (7)
C140.0188 (8)0.0273 (9)0.0290 (9)0.0019 (7)0.0038 (7)0.0072 (7)
C150.0260 (9)0.0229 (9)0.0232 (8)0.0013 (7)0.0067 (7)0.0006 (7)
F10.0413 (7)0.0402 (8)0.0330 (7)0.0202 (6)0.0063 (5)0.0036 (5)
Geometric parameters (Å, º) top
C1—O11.252 (2)C8—C91.330 (3)
C1—O21.291 (2)C8—H80.9500
C1—C21.479 (2)C9—C101.471 (2)
O2—H21.04 (4)C9—H90.9500
C2—C31.392 (3)C10—C151.392 (3)
C2—C71.393 (3)C10—C111.402 (3)
C3—C41.382 (2)C11—C121.390 (3)
C3—H30.9500C11—H110.9500
C4—C51.394 (3)C12—C131.380 (3)
C4—H40.9500C12—H120.9500
C5—C61.401 (3)C13—F11.363 (2)
C5—C81.473 (2)C13—C141.369 (3)
C6—C71.389 (2)C14—C151.389 (3)
C6—H60.9500C14—H140.9500
C7—H70.9500C15—H150.9500
O1—C1—O2123.07 (15)C9—C8—H8116.9
O1—C1—C2120.16 (15)C5—C8—H8116.9
O2—C1—C2116.78 (15)C8—C9—C10125.99 (18)
C1—O2—H2112 (2)C8—C9—H9117.0
C3—C2—C7119.79 (15)C10—C9—H9117.0
C3—C2—C1119.41 (16)C15—C10—C11118.25 (16)
C7—C2—C1120.80 (16)C15—C10—C9118.07 (17)
C4—C3—C2120.05 (17)C11—C10—C9123.68 (17)
C4—C3—H3120.0C12—C11—C10120.96 (18)
C2—C3—H3120.0C12—C11—H11119.5
C3—C4—C5121.11 (18)C10—C11—H11119.5
C3—C4—H4119.4C13—C12—C11118.08 (18)
C5—C4—H4119.4C13—C12—H12121.0
C4—C5—C6118.38 (16)C11—C12—H12121.0
C4—C5—C8117.69 (17)F1—C13—C14118.85 (18)
C6—C5—C8123.92 (17)F1—C13—C12118.02 (18)
C7—C6—C5120.88 (17)C14—C13—C12123.12 (17)
C7—C6—H6119.6C13—C14—C15118.00 (17)
C5—C6—H6119.6C13—C14—H14121.0
C6—C7—C2119.77 (17)C15—C14—H14121.0
C6—C7—H7120.1C14—C15—C10121.58 (18)
C2—C7—H7120.1C14—C15—H15119.2
C9—C8—C5126.22 (18)C10—C15—H15119.2
O1—C1—C2—C36.5 (2)C6—C5—C8—C97.2 (3)
O2—C1—C2—C3173.26 (15)C5—C8—C9—C10179.93 (17)
O1—C1—C2—C7174.23 (16)C8—C9—C10—C15175.06 (18)
O2—C1—C2—C76.0 (2)C8—C9—C10—C115.5 (3)
C7—C2—C3—C40.1 (3)C15—C10—C11—C120.1 (3)
C1—C2—C3—C4179.31 (16)C9—C10—C11—C12179.26 (17)
C2—C3—C4—C51.0 (3)C10—C11—C12—C130.4 (3)
C3—C4—C5—C61.1 (3)C11—C12—C13—F1179.25 (16)
C3—C4—C5—C8179.83 (16)C11—C12—C13—C140.1 (3)
C4—C5—C6—C70.2 (3)F1—C13—C14—C15178.64 (16)
C8—C5—C6—C7179.19 (17)C12—C13—C14—C150.7 (3)
C5—C6—C7—C20.9 (3)C13—C14—C15—C100.9 (3)
C3—C2—C7—C61.0 (3)C11—C10—C15—C140.5 (3)
C1—C2—C7—C6179.80 (15)C9—C10—C15—C14179.93 (16)
C4—C5—C8—C9173.72 (19)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O1i1.04 (4)1.57 (4)2.610 (2)174 (3)
Symmetry code: (i) x+2, y, z+2.

Experimental details

Crystal data
Chemical formulaC15H11FO2
Mr242.24
Crystal system, space groupMonoclinic, P21/c
Temperature (K)123
a, b, c (Å)6.261 (4), 23.096 (15), 8.269 (5)
β (°) 107.072 (8)
V3)1143.1 (13)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.45 × 0.30 × 0.18
Data collection
DiffractometerRigaku/MSC Mercury CCD
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
9111, 2589, 2399
Rint0.036
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.065, 0.155, 1.16
No. of reflections2589
No. of parameters167
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.55, 0.28

Computer programs: CrystalClear (MSC/Rigaku, 2001), TEXSAN (MSC/Rigaku , 2004), SIR97 (Altomare et al., 1999), ORTEPII (Johnson, 1976), SHELXL97 (Sheldrick, 2008) and TEXSAN (MSC/Rigaku, 2004).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O1i1.04 (4)1.57 (4)2.610 (2)174 (3)
Symmetry code: (i) x+2, y, z+2.
 

Acknowledgements

MKR is grateful to the Higher Education Commission of Pakistan for financial support under the International Support Initiative for Doctoral Fellowships at Gifu University, Japan.

References

First citationAhmad, H. B., Rama, N. H., Hussain, M., Hussain, M. T., Qasim, M. M., Hameed, S., Malana, M. A. & Malik, A. (2003). Indian J. Chem. B42, 611–615.  Google Scholar
First citationAltomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115–119.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationCollings, P. J. & Hird, M. (1997). Introduction to Liquid Crystals, Chemistry and Physics, edited by G. W. Gray, J. W. Goodby & A. Fukuda, pp. 43–78. Bristol: Taylor and Francis.  Google Scholar
First citationFrazee, L. A. & Foraker, K. C. (2008). Annals Pharmacother. 42, 403–407.  Web of Science CrossRef CAS Google Scholar
First citationHameed, S. & Rama, N. H. (2004). J. Chem. Soc. Pak. 26, 157–162.  CAS Google Scholar
First citationHigashi, T. (1999). NUMABS. Rigaku Corporation, 3-9-12 Akishima, Tokyo 196-8666, Japan.  Google Scholar
First citationHussain, M. T., Rama, N. H., Hameed, S., Malik, A. & Khan, K. M. (2005). Nat. Prod. Res. 19, 41–51.  Web of Science CrossRef PubMed CAS Google Scholar
First citationJohnson, C. K. (1976). ORTEPII. Report ORNL-5138. Oak Ridge National Laboratory, Tennessee, USA.  Google Scholar
First citationMSC/Rigaku (2001). CrystalClear. MSC/Rigaku, The Woodlands, Texas, USA.  Google Scholar
First citationMSC/Rigaku (2004). TEXSAN. MSC/Rigaku, The Woodlands, Texas, USA.  Google Scholar
First citationNazir, S., Khawar Rauf, M., Ebihara, M. & Hameed, S. (2008). Acta Cryst. E64, o423.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationRibeiro, G., Benadiba, M., Colquhoun, A. & Silva, D. D. (2008). Polyhedron, 27, 1131–1137.  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 citationWang, M. L., Liu, B. L. & Lin, S. J. (2008). Chem. Eng. Commun. 195, 770–786.  Web of Science CrossRef CAS Google Scholar
First citationYasuda, N., Uekusa, H. & Ohashi, Y. (2000). Acta Cryst. C56, 1364–1366.  CSD 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.

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