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Acta Crystallogr Sect E Struct Rep Online. 2010 July 1; 66(Pt 7): o1529–o1530.
Published online 2010 June 5. doi:  10.1107/S1600536810019999
PMCID: PMC3006934

N-(4-Meth­oxy­phen­yl)maleamic acid

Abstract

In the title compound, C11H11NO4, the asymmetric unit contains two unique mol­ecules, both of which are almost planar, with r.m.s. deviations of 0.047 and 0.059 Å. The dihedral angles between the benzene ring and the plane of maleamic acid unit are 3.43 (5) and 5.79 (3)° in the two mol­ecules. The mol­ecular structures are stabilized by a short intra­molecular O—H(...)O hydrogen bond within each maleamic acid unit. In the crystal, inter­molecular N—H(...)O hydrogen bonds link the mol­ecules into zigzag chains extending along [1An external file that holds a picture, illustration, etc.
Object name is e-66-o1529-efi1.jpg0]. Weak intermolecular C—H(...)O hydrogen bonds also exist.

Related literature

For studies on the effect of ring- and side-chain substitutions on the crystal structures of amides, see: Gowda et al. (2009a [triangle],b [triangle],c [triangle]); Prasad et al. (2002 [triangle]). For the modes of inter­linking carb­oxy­lic acids by hydrogen bonds, see: Jagannathan et al. (1994 [triangle]); Leiserowitz (1976 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o1529-scheme1.jpg

Experimental

Crystal data

  • C11H11NO4
  • M r = 221.21
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1529-efi2.jpg
  • a = 7.34030 (17) Å
  • b = 11.8258 (4) Å
  • c = 12.1207 (4) Å
  • α = 89.103 (3)°
  • β = 88.358 (2)°
  • γ = 78.396 (2)°
  • V = 1030.15 (5) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.11 mm−1
  • T = 295 K
  • 0.54 × 0.25 × 0.22 mm

Data collection

  • Oxford Diffraction Gemini R CCD diffractometer
  • Absorption correction: analytical (CrysAlis PRO; Oxford Diffraction, 2009 [triangle]) T min = 0.962, T max = 0.980
  • 15439 measured reflections
  • 3711 independent reflections
  • 2923 reflections with I > 2σ(I)
  • R int = 0.020

Refinement

  • R[F 2 > 2σ(F 2)] = 0.035
  • wR(F 2) = 0.097
  • S = 1.02
  • 3711 reflections
  • 291 parameters
  • H-atom parameters constrained
  • Δρmax = 0.14 e Å−3
  • Δρmin = −0.20 e Å−3

Data collection: CrysAlis PRO (Oxford Diffraction, 2009 [triangle]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]) and DIAMOND (Brandenburg, 2002 [triangle]); software used to prepare material for publication: SHELXL97, PLATON (Spek, 2009 [triangle]) and WinGX (Farrugia, 1999 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810019999/bq2215sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810019999/bq2215Isup2.hkl

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

Acknowledgments

MT and JK thank the Grant Agency of the Slovak Republic (VEGA 1/0817/08) and Structural Funds, Inter­reg IIIA, for financial support to purchase the diffractometer. KS thanks the University Grants Commission, Government of India, New Delhi, for the award of a research fellowship under its faculty improvement program.

supplementary crystallographic information

Comment

As a part of studying the effect of the ring and side chain substitutions on the crystal structures of biologically significant amides (Gowda et al., 2009a,b,c; Prasad et al., 2002), in the present work, the crystal structure of N-(4-methoxyphenyl)maleamic acid (I) has been determined (Fig. 1). The asymmetric unit of the structure contains two unique molecules. Both the molecules are almost planar with r.m.s deviations of 0.047Å and 0.059Å for the two molecules (Fig. 1).

The conformations of the N—H and the C=O bonds in the amide segment are anti to each other. In the side chain, the amide C=O bond is anti to the adjacent C—H bond, while the carboxyl C=O bond is syn to the adjacent C—H bond. The observed rare anti conformation of the C=O and O—H bonds of the acid group is similar to that obsrved in N-(2,6-dimethylphenyl)-maleamic acid (Gowda et al., 2009a), N-(3,4-dimethylphenyl)-maleamic acid (Gowda et al., 2009b) and N-(2,4,6-trimethylphenyl)- maleamic acid (Gowda et al., 2009c).

The dihedral angles between the phenyl ring and the plane of maleamic acid moiety are 3.43 (5)° and 5.79 (3)° in the first and second molecules, respectively. The molecular structure is stabilized by a short O–H···O intramolecular hydrogen bond (Table 1) within each maleamic acid moiety. The orientations of the methoxy groups toward the phenyl rings are given by the torsion angles, C7—C8—O4—C11 = -8.2 (2)° and C27—C28—O8—C31 = 0.7 (2)°. In the crystal structure (Fig. 2), the intermolecular N–H···O hydrogen bonds link the molecules into zigzag chains extending along the [1 -1 0] direction. Weak intermolecular C-H···O hydrogen bonds also exist in the structure.

The various modes of interlinking carboxylic acids by hydrogen bonds is described elsewhere (Leiserowitz, 1976). The packing of molecules involving dimeric hydrogen bonded association of each carboxyl group with a centrosymmetrically related neighbor has also been observed (Jagannathan et al., 1994).

Experimental

The solution of maleic anhydride (0.025 mol) in toluene (25 ml) was treated dropwise with the solution of 4-methoxyaniline (0.025 mol) also in toluene (20 ml) with constant stirring. The resulting mixture was stirred for about 30 min and set aside for an additional 30 min at room temperature for the completion of reaction. The mixture was then treated with dilute hydrochloric acid to remove the unreacted 4-methoxyaniline. The resultant solid N-(4-methoxyphenyl)maleamic acid was filtered under suction and washed thoroughly with water to remove the unreacted maleic anhydride and maleic acid. It was recrystallized to constant melting point from ethanol. The purity of the compound was checked by elemental analysis and characterized by its infrared spectra. Prism like yellowish green single crystals of the title compound used in X-ray diffraction studies were grown in an ethanol solution by slow evaporation at room temperature.

Refinement

All H atoms were visible in difference maps and were further positioned with idealized geometry (C–H = 0.93 or 0.96 Å, N–H = 0.86 Å, O–H = 0.92 Å) and refined using a riding model. The Uiso(H) values were set at 1.2Ueq(C aromatic, N) and 1.5Ueq(C methyl, O).

Figures

Fig. 1.
Molecular structure of (I) showing the atom labeling scheme. Displacement ellipsoids are drawn at the 50% probability level. Intramolecular O—H···O bonds are shown as dashed lines.
Fig. 2.
Part of the crystal structure of (I) showing zigzag chains of molecules linked by intermolecular N—H···O hydrogen bonds, represented by dashed lines. Symmetry codes (i): -x,-y + 2,-z + 1; (ii) -x + 1,-y + 1,-z + 1. H atoms ...

Crystal data

C11H11NO4Z = 4
Mr = 221.21F(000) = 464
Triclinic, P1Dx = 1.426 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.34030 (17) ÅCell parameters from 8581 reflections
b = 11.8258 (4) Åθ = 1.8–29.5°
c = 12.1207 (4) ŵ = 0.11 mm1
α = 89.103 (3)°T = 295 K
β = 88.358 (2)°Prism, yellow–green
γ = 78.396 (2)°0.54 × 0.25 × 0.22 mm
V = 1030.15 (5) Å3

Data collection

Oxford Diffraction Gemini R CCD diffractometer3711 independent reflections
graphite2923 reflections with I > 2σ(I)
Detector resolution: 10.434 pixels mm-1Rint = 0.020
ω scansθmax = 25.2°, θmin = 2.4°
Absorption correction: analytical (CrysAlis PRO; Oxford Diffraction, 2009)h = −8→8
Tmin = 0.962, Tmax = 0.980k = −14→14
15439 measured reflectionsl = −14→14

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)] = 0.035Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.097H-atom parameters constrained
S = 1.02w = 1/[σ2(Fo2) + (0.0619P)2 + 0.0566P] where P = (Fo2 + 2Fc2)/3
3711 reflections(Δ/σ)max < 0.001
291 parametersΔρmax = 0.14 e Å3
0 restraintsΔρmin = −0.20 e Å3

Special details

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)

xyzUiso*/Ueq
C10.25076 (17)0.51156 (11)0.57066 (10)0.0407 (3)
C20.23780 (18)0.54345 (11)0.68793 (11)0.0431 (3)
H20.17320.61770.70350.052*
C30.30661 (18)0.47979 (12)0.77505 (11)0.0466 (3)
H30.28260.51790.84210.056*
C40.41425 (18)0.35955 (12)0.78463 (11)0.0459 (3)
C50.15402 (16)0.58696 (10)0.38503 (10)0.0386 (3)
C60.05175 (18)0.68231 (11)0.33150 (11)0.0439 (3)
H6−0.00840.74520.37270.053*
C70.03742 (18)0.68568 (11)0.21824 (11)0.0457 (3)
H7−0.03140.75060.18380.055*
C80.12554 (18)0.59239 (11)0.15582 (10)0.0444 (3)
C90.2264 (2)0.49671 (12)0.20906 (11)0.0518 (4)
H90.2860.43370.16770.062*
C100.24030 (19)0.49303 (12)0.32182 (11)0.0487 (3)
H100.30760.42750.35610.058*
C110.0013 (2)0.67727 (14)−0.01187 (12)0.0599 (4)
H11A0.00470.6609−0.08930.09*
H11B0.04080.7488−0.0010.09*
H11C−0.12330.68320.01710.09*
N10.16464 (14)0.59247 (9)0.50150 (8)0.0406 (3)
H1N0.10850.6560.53120.049*
O10.33527 (15)0.41551 (8)0.53737 (8)0.0625 (3)
O20.45825 (14)0.29623 (8)0.69728 (8)0.0593 (3)
H2A0.41960.33940.63530.089*
O30.45985 (15)0.32053 (9)0.87533 (8)0.0644 (3)
O40.12243 (14)0.58681 (9)0.04387 (8)0.0602 (3)
C210.22420 (17)0.98092 (11)0.13550 (10)0.0415 (3)
C220.21905 (18)0.94474 (11)0.25224 (10)0.0436 (3)
H220.27510.86850.26710.052*
C230.14486 (18)1.00662 (12)0.33956 (11)0.0464 (3)
H230.15130.96480.40550.056*
C240.05379 (18)1.13023 (12)0.35040 (11)0.0452 (3)
C250.33278 (16)0.91072 (11)−0.05093 (10)0.0390 (3)
C260.40524 (19)0.81103 (11)−0.10879 (11)0.0501 (3)
H260.43330.7409−0.0710.06*
C270.4366 (2)0.81386 (12)−0.22171 (11)0.0512 (3)
H270.48530.7461−0.25930.061*
C280.39523 (18)0.91759 (11)−0.27842 (10)0.0448 (3)
C290.3238 (2)1.01727 (12)−0.22083 (11)0.0528 (4)
H290.29621.0874−0.25870.063*
C300.2928 (2)1.01469 (12)−0.10878 (11)0.0503 (3)
H300.24481.0828−0.07140.06*
C310.4932 (2)0.83253 (14)−0.45312 (12)0.0605 (4)
H31A0.50830.855−0.52870.091*
H31B0.40890.7801−0.44840.091*
H31C0.61160.7952−0.42530.091*
N20.30677 (14)0.90022 (9)0.06518 (8)0.0425 (3)
H2N0.34980.83340.09340.051*
O50.15438 (16)1.08043 (9)0.10395 (8)0.0675 (3)
O60.03939 (18)1.19821 (9)0.26512 (9)0.0740 (4)
H6A0.08151.1560.2030.111*
O7−0.00459 (15)1.16789 (9)0.44012 (8)0.0625 (3)
O80.42056 (16)0.93176 (9)−0.38950 (8)0.0622 (3)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0464 (7)0.0308 (7)0.0407 (7)0.0016 (5)0.0001 (5)0.0018 (5)
C20.0502 (7)0.0308 (7)0.0424 (7)0.0056 (5)0.0015 (5)0.0002 (6)
C30.0562 (8)0.0393 (7)0.0378 (7)0.0058 (6)−0.0007 (6)−0.0002 (6)
C40.0510 (7)0.0391 (7)0.0426 (8)0.0026 (6)−0.0006 (6)0.0064 (6)
C50.0423 (7)0.0328 (7)0.0381 (7)−0.0017 (5)0.0005 (5)0.0024 (5)
C60.0551 (8)0.0307 (7)0.0415 (7)0.0020 (6)−0.0001 (6)−0.0008 (6)
C70.0561 (8)0.0318 (7)0.0438 (8)0.0038 (6)−0.0042 (6)0.0047 (6)
C80.0518 (8)0.0410 (8)0.0372 (7)−0.0015 (6)−0.0012 (6)0.0007 (6)
C90.0604 (8)0.0417 (8)0.0436 (8)0.0128 (6)−0.0003 (6)−0.0046 (6)
C100.0566 (8)0.0375 (7)0.0438 (8)0.0101 (6)−0.0027 (6)0.0028 (6)
C110.0771 (10)0.0557 (9)0.0396 (8)0.0045 (7)−0.0068 (7)0.0071 (7)
N10.0487 (6)0.0303 (5)0.0375 (6)0.0045 (4)0.0011 (4)0.0013 (5)
O10.0925 (8)0.0384 (6)0.0427 (6)0.0204 (5)−0.0047 (5)−0.0015 (4)
O20.0821 (7)0.0365 (5)0.0472 (6)0.0170 (5)−0.0037 (5)0.0029 (5)
O30.0822 (7)0.0526 (6)0.0468 (6)0.0141 (5)−0.0062 (5)0.0118 (5)
O40.0797 (7)0.0535 (6)0.0361 (5)0.0137 (5)−0.0050 (5)−0.0008 (5)
C210.0456 (7)0.0337 (7)0.0403 (7)0.0037 (5)0.0009 (5)−0.0005 (6)
C220.0523 (7)0.0307 (7)0.0420 (7)0.0050 (5)0.0017 (6)0.0036 (6)
C230.0565 (8)0.0392 (7)0.0381 (7)0.0026 (6)0.0034 (6)0.0050 (6)
C240.0504 (7)0.0392 (7)0.0413 (8)0.0020 (6)0.0032 (6)−0.0032 (6)
C250.0416 (7)0.0351 (7)0.0369 (7)0.0002 (5)−0.0007 (5)−0.0011 (5)
C260.0687 (9)0.0329 (7)0.0424 (8)0.0043 (6)0.0006 (6)0.0018 (6)
C270.0699 (9)0.0348 (7)0.0429 (8)0.0036 (6)0.0022 (6)−0.0081 (6)
C280.0552 (8)0.0406 (8)0.0367 (7)−0.0048 (6)−0.0002 (6)−0.0021 (6)
C290.0748 (9)0.0344 (7)0.0436 (8)0.0015 (6)0.0044 (7)0.0038 (6)
C300.0675 (9)0.0332 (7)0.0443 (8)0.0030 (6)0.0069 (6)−0.0036 (6)
C310.0817 (10)0.0549 (9)0.0413 (8)−0.0047 (8)0.0054 (7)−0.0117 (7)
N20.0533 (6)0.0313 (6)0.0375 (6)0.0041 (5)0.0010 (5)0.0014 (5)
O50.1026 (8)0.0409 (6)0.0420 (6)0.0240 (5)0.0096 (5)0.0054 (5)
O60.1190 (9)0.0380 (6)0.0475 (6)0.0228 (6)0.0169 (6)0.0035 (5)
O70.0846 (7)0.0484 (6)0.0447 (6)0.0092 (5)0.0093 (5)−0.0084 (5)
O80.0996 (8)0.0456 (6)0.0354 (5)−0.0009 (5)0.0053 (5)−0.0028 (4)

Geometric parameters (Å, °)

C1—O11.2468 (15)C21—O51.2444 (15)
C1—N11.3341 (16)C21—N21.3295 (16)
C1—C21.4719 (18)C21—C221.4735 (18)
C2—C31.3377 (18)C22—C231.3353 (18)
C2—H20.93C22—H220.93
C3—C41.4858 (18)C23—C241.4862 (19)
C3—H30.93C23—H230.93
C4—O31.2151 (16)C24—O71.2151 (16)
C4—O21.3015 (16)C24—O61.2930 (17)
C5—C61.3858 (17)C25—C261.3845 (18)
C5—C101.3921 (18)C25—C301.3890 (18)
C5—N11.4193 (16)C25—N21.4217 (16)
C6—C71.3792 (18)C26—C271.3824 (18)
C6—H60.93C26—H260.93
C7—C81.3853 (19)C27—C281.3803 (19)
C7—H70.93C27—H270.93
C8—O41.3606 (16)C28—O81.3662 (16)
C8—C91.3829 (19)C28—C291.3812 (19)
C9—C101.3728 (19)C29—C301.3715 (19)
C9—H90.93C29—H290.93
C10—H100.93C30—H300.93
C11—O41.4213 (17)C31—O81.4174 (17)
C11—H11A0.96C31—H31A0.96
C11—H11B0.96C31—H31B0.96
C11—H11C0.96C31—H31C0.96
N1—H1N0.86N2—H2N0.86
O2—H2A0.92O6—H6A0.92
O1—C1—N1121.77 (12)O5—C21—N2121.73 (11)
O1—C1—C2122.78 (12)O5—C21—C22122.37 (12)
N1—C1—C2115.45 (11)N2—C21—C22115.89 (11)
C3—C2—C1128.61 (12)C23—C22—C21128.78 (12)
C3—C2—H2115.7C23—C22—H22115.6
C1—C2—H2115.7C21—C22—H22115.6
C2—C3—C4131.96 (13)C22—C23—C24131.60 (13)
C2—C3—H3114C22—C23—H23114.2
C4—C3—H3114C24—C23—H23114.2
O3—C4—O2120.22 (12)O7—C24—O6119.93 (12)
O3—C4—C3119.17 (13)O7—C24—C23119.81 (13)
O2—C4—C3120.61 (11)O6—C24—C23120.25 (12)
C6—C5—C10118.38 (12)C26—C25—C30118.52 (12)
C6—C5—N1117.26 (11)C26—C25—N2117.52 (11)
C10—C5—N1124.36 (11)C30—C25—N2123.95 (11)
C7—C6—C5121.26 (12)C27—C26—C25121.19 (12)
C7—C6—H6119.4C27—C26—H26119.4
C5—C6—H6119.4C25—C26—H26119.4
C6—C7—C8120.00 (12)C28—C27—C26119.77 (12)
C6—C7—H7120C28—C27—H27120.1
C8—C7—H7120C26—C27—H27120.1
O4—C8—C9116.12 (12)O8—C28—C27125.33 (12)
O4—C8—C7124.99 (12)O8—C28—C29115.50 (12)
C9—C8—C7118.89 (12)C27—C28—C29119.17 (12)
C10—C9—C8121.19 (13)C30—C29—C28121.17 (13)
C10—C9—H9119.4C30—C29—H29119.4
C8—C9—H9119.4C28—C29—H29119.4
C9—C10—C5120.27 (12)C29—C30—C25120.18 (12)
C9—C10—H10119.9C29—C30—H30119.9
C5—C10—H10119.9C25—C30—H30119.9
O4—C11—H11A109.5O8—C31—H31A109.5
O4—C11—H11B109.5O8—C31—H31B109.5
H11A—C11—H11B109.5H31A—C31—H31B109.5
O4—C11—H11C109.5O8—C31—H31C109.5
H11A—C11—H11C109.5H31A—C31—H31C109.5
H11B—C11—H11C109.5H31B—C31—H31C109.5
C1—N1—C5128.19 (11)C21—N2—C25128.07 (11)
C1—N1—H1N115.9C21—N2—H2N116
C5—N1—H1N115.9C25—N2—H2N116
C4—O2—H2A109.5C24—O6—H6A109.5
C8—O4—C11117.28 (11)C28—O8—C31118.13 (11)
O1—C1—C2—C3−1.0 (2)O5—C21—C22—C23−0.1 (2)
N1—C1—C2—C3178.62 (13)N2—C21—C22—C23−179.46 (13)
C1—C2—C3—C4−0.6 (2)C21—C22—C23—C24−3.5 (2)
C2—C3—C4—O3−179.27 (15)C22—C23—C24—O7179.83 (14)
C2—C3—C4—O20.2 (2)C22—C23—C24—O6−1.4 (2)
C10—C5—C6—C7−1.04 (19)C30—C25—C26—C27−0.4 (2)
N1—C5—C6—C7178.47 (11)N2—C25—C26—C27−179.36 (12)
C5—C6—C7—C80.3 (2)C25—C26—C27—C280.0 (2)
C6—C7—C8—O4−179.29 (12)C26—C27—C28—O8179.68 (13)
C6—C7—C8—C90.3 (2)C26—C27—C28—C290.3 (2)
O4—C8—C9—C10179.56 (12)O8—C28—C29—C30−179.67 (12)
C7—C8—C9—C100.0 (2)C27—C28—C29—C30−0.2 (2)
C8—C9—C10—C5−0.8 (2)C28—C29—C30—C25−0.1 (2)
C6—C5—C10—C91.27 (19)C26—C25—C30—C290.4 (2)
N1—C5—C10—C9−178.21 (12)N2—C25—C30—C29179.36 (12)
O1—C1—N1—C5−0.7 (2)O5—C21—N2—C251.0 (2)
C2—C1—N1—C5179.61 (10)C22—C21—N2—C25−179.59 (11)
C6—C5—N1—C1178.55 (12)C26—C25—N2—C21−173.12 (12)
C10—C5—N1—C1−2.0 (2)C30—C25—N2—C218.0 (2)
C9—C8—O4—C11172.28 (13)C27—C28—O8—C310.7 (2)
C7—C8—O4—C11−8.2 (2)C29—C28—O8—C31−179.88 (12)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O2—H2A···O10.921.552.4624 (13)174
O6—H6A···O50.921.532.4466 (14)177
N1—H1N···O7i0.862.102.9305 (14)162
N2—H2N···O3ii0.862.102.9124 (14)158
C2—H2···O6i0.932.443.3592 (16)171
C6—H6···O7i0.932.523.2822 (17)140
C22—H22···O2ii0.932.513.3792 (16)156
C26—H26···O3ii0.932.573.2881 (16)135
C11—H11B···O5iii0.962.563.0688 (18)113

Symmetry codes: (i) −x, −y+2, −z+1; (ii) −x+1, −y+1, −z+1; (iii) −x, −y+2, −z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BQ2215).

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