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

Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 67| Part 6| June 2011| Pages o1509-o1510

A third monoclinic polymorph of 3,4,5-trihy­dr­oxy­benzoic acid monohydrate

aDepartment of Physics, Arts and Sciences Faculty, Ondokuz Mayıs University, 55139 Samsun, Turkey
*Correspondence e-mail: gunesd@omu.edu.tr

(Received 30 April 2011; accepted 17 May 2011; online 25 May 2011)

The title compound, C7H6O5·H2O, is a new polymorph of the structures reported by Jiang et al. (2000[Jiang, R.-W., Ming, D.-S., But, P. P. H. & Mak, T. C. W. (2000). Acta Cryst. C56, 594-595.]) [Acta Cryst. C56, 594–595] and Okabe et al. (2001[Okabe, N., Kyoyama, H. & Suzuki, M. (2001). Acta Cryst. E57, o764-o766.]) [Acta Cryst. E57, o764–o766]. The gallic acid mol­ecule is essentially planar (r.m.s. deviation = 0.550 Å). An intra­molecular O—H⋯O hydrogen bond occurs in the gallic acid mol­ecule, which is linked to the water mol­ecule by a further O—H⋯O hydrogen bond. In the crystal, the components are linked by O—H⋯O hydrogen bonds. The hydrogen-bonding pattern differs from those reported for the previous polymorphs.

Related literature

For the biological activity of gallic acid, see: Lu et al. (2006[Lu, Z., Nie, G., Belton, P. S., Tang, H. & Zhao, B. (2006). Neurochem. Int. 48, 263-274.]); Madlener et al. (2007[Madlener, S., Illmer, C., Horvath, Z., Saiko, P., Losert, A., Herbacek, I., Grusch, M., Elford, H. L., Krupitza, G., Bernhaus, A., Fritzer-Szekeres, M. & Szekeres, T. (2007). Cancer Lett. 245, 156-162.]). For the previously reproted polymorphs, see: Jiang et al. (2000[Jiang, R.-W., Ming, D.-S., But, P. P. H. & Mak, T. C. W. (2000). Acta Cryst. C56, 594-595.]); Okabe et al. (2001[Okabe, N., Kyoyama, H. & Suzuki, M. (2001). Acta Cryst. E57, o764-o766.]). For a related structure, see: Genç et al. (2004[Genç, S., Dege, N., Çetin, A., Cansız, A., Şekerci, M. & Dinçer, M. (2004). Acta Cryst. E60, o1580-o1582.]).

[Scheme 1]

Experimental

Crystal data
  • C7H6O5·H2O

  • Mr = 188.13

  • Monoclinic, P 21 /c

  • a = 9.7943 (7) Å

  • b = 3.6122 (2) Å

  • c = 21.5905 (15) Å

  • β = 91.268 (6)°

  • V = 763.66 (9) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.15 mm−1

  • T = 296 K

  • 0.61 × 0.28 × 0.09 mm

Data collection
  • Stoe IPDS 2 diffractometer

  • Absorption correction: integration (X-RED32; Stoe & Cie, 2002[Stoe & Cie (2002). X-AREA and X-RED32. Stoe & Cie, Darmstadt, Germany. ]) Tmin = 0.948, Tmax = 0.986

  • 4558 measured reflections

  • 1502 independent reflections

  • 1262 reflections with I > 2σ(I)

  • Rint = 0.042

Refinement
  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.104

  • S = 1.04

  • 1502 reflections

  • 127 parameters

  • 3 restraints

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

  • Δρmax = 0.15 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H3⋯O3 0.82 2.26 2.7006 (18) 114
O5—H6⋯O6 0.82 1.85 2.6542 (17) 167
O1—H2⋯O6i 0.82 2.03 2.7539 (19) 147
O2—H3⋯O3ii 0.82 2.52 3.1721 (19) 137
O3—H4⋯O4iii 0.82 1.94 2.7154 (19) 158
O6—H6A⋯O2iv 0.83 (2) 2.03 (2) 2.8237 (19) 161 (3)
O6—H6B⋯O1v 0.82 (2) 2.00 (2) 2.814 (2) 171 (5)
Symmetry codes: (i) -x+1, -y+2, -z+1; (ii) [-x+2, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iii) [-x+1, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iv) x-1, y+1, z; (v) x-1, y, z.

Table 2
Other crystal structures of gallic acid monohydrate (Å, °)

  1 2
Unit-cell parameters a = 5.794 (4) a = 14.15 (1)
  b = 4.719 (5) b = 3.622 (9)
  c = 28.688 (5) c = 15.028 (10)
  β = 95.08 (3) β = 97.52 (7)
  V = 781.4 (3) V = 764 (1)
Space group Monoclinic, P21/c Monoclinic, P2/n
Reference Jiang et al. (2000[Jiang, R.-W., Ming, D.-S., But, P. P. H. & Mak, T. C. W. (2000). Acta Cryst. C56, 594-595.]) Okabe et al. (2001[Okabe, N., Kyoyama, H. & Suzuki, M. (2001). Acta Cryst. E57, o764-o766.])

Data collection: X-AREA (Stoe & Cie, 2002[Stoe & Cie (2002). X-AREA and X-RED32. Stoe & Cie, Darmstadt, Germany. ]); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002[Stoe & Cie (2002). X-AREA and X-RED32. Stoe & Cie, Darmstadt, Germany. ]); program(s) used to solve structure: WinGX (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and 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, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Gallic acid and its derivatives are a group of naturally occurring polyphenol antioxidants which have recently been shown to have potential healty effects as an excellent free radical scavenger (Lu et al., 2006). In adition, gallic acid block DNA synthesis in leukemia cells (Madlener et al., 2007). Up to now, the different crystal structure of gallic acid monohidrate form have been reported by (Jiang et al., 2000; Okabe et al., 2001). The unit-cell parameters belong to these crystal structures have given at Table 2.

We report here the crystal structure of the title compound, C7H6O5.H2O. The asymmetric unit of title compound, C7H6O5.H2O, consists of one 3,4,5-trihydroxybenzoic acid molecule and one water molecule (Fig. 1). The C—C bond distances range from 1.378 (2) Å to 1.480 (2) Å. The longest C—C bond distance is between C6 and C7 with 1.480 Å. The C—O bond distance are range from 1.212 (2) Å to 1.3723 (19) Å. The shortest C—O bond distance is between C7 and O4 with 1.212 (2) Å. The C—O bond distance for different crystal structure was given 1.359 (2) Å by (Genç et al., 2004).

The crystal structure has two intramolecular hydrogen bonds and five intermolecular hydrogen bonds (Table 1). The O2—H3···O3 and O5—H6···O6 hydrogen bonds present in the asymmetric unit. In the crystal structure, the gallic acid molecules and water molecules are linked by the O6—H6A···O2, O6—H6B···O1, O5—H6···O6 and O1—H2···O6 hydrogen bonds. While the C—H···O hydrogen bond is present in crystal structure reported by (Jiang et al., 2000), there isn't present in our crystal structure. The via hydrogen atom of water molecule makes bifurcated hydrogen bond in crystal structure reported by (Jiang et al., 2000),but this kind hydrogen bond is not present in our crystal structure. In crystal structure reported by (Okabe et al., 2001), the hydroxyl groups make two intramolecular hydrogen bonds.

The torsion angles at ring belong to gallic acid molecule are range from 0.0 (3)° to 1.9 (3)°. Therefore, the gallic acid molecule close to planar. The tosion angles for the C2—C1—C6—C7 and C4—C5—C6—C7 are 179.51 (16)° and -179.08 (17)°, respectively. The O4—C7—O5 angle is 122.82 (15)°.

Related literature top

For the biological activity of gallic acid, see: Lu et al. (2006); Madlener et al. (2007). For the previously reproted polymorphs, see: Jiang et al. (2000); Okabe et al. (2001). For a related structure, see: Genç et al. (2004).

Experimental top

A hot solution (60 °C) of gallic acid (0.002 mol, 0.340 g) in distilled water (approximately 20 ml) was gradually added to a hot stirring solution of magnesium sulfate heptahydrate (MgSO4.7H2O) (0.001 mol, 0.246 g) in distilled water (approximately 20 ml). The obtained mixture was stirred on a hot plate with slow evaporation to 30 ml at 60° C. The mixture was left for crystallization and in a few days, the crystals were obtained by slow evaporation from the solution at room temperature.

Refinement top

H6A and H6B atoms were located in a difference map and were refined isotropically, with O—H distances in the range 0.830 (18)-0.824 (19) Å, and the H···H distance of 1.320 (2) Å. The other H atoms were positioned geometrically and refined using a riding model, with C—H = 0.930 Å, O—H = 0.820 Å, and Uiso(H) = 1.2Ueq(C) and 1.5Ueq(O).

Computing details top

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA (Stoe & Cie, 2002); data reduction: X-RED32 (Stoe & Cie, 2002); program(s) used to solve structure: WinGX (Farrugia, 1997) and SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the title compound, showing the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. Packing diagram for (I), showing the three-dimensional hydrogen bonding array. Hydrogen bonds are shown as dashed lines.
3,4,5-trihydroxybenzoic acid monohydrate top
Crystal data top
C7H6O5·H2OF(000) = 392
Mr = 188.13Dx = 1.636 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 6472 reflections
a = 9.7943 (7) Åθ = 1.9–27.6°
b = 3.6122 (2) ŵ = 0.15 mm1
c = 21.5905 (15) ÅT = 296 K
β = 91.268 (6)°Needle, pale brown
V = 763.66 (9) Å30.61 × 0.28 × 0.09 mm
Z = 4
Data collection top
Stoe IPDS 2
diffractometer
1502 independent reflections
Radiation source: fine-focus sealed tube1262 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.042
w–scan rotationθmax = 26.0°, θmin = 1.9°
Absorption correction: integration
(X-RED32; Stoe & Cie, 2002)
h = 912
Tmin = 0.948, Tmax = 0.986k = 44
4558 measured reflectionsl = 2626
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.039H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.104 w = 1/[σ2(Fo2) + (0.0466P)2 + 0.2493P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max < 0.001
1502 reflectionsΔρmax = 0.15 e Å3
127 parametersΔρmin = 0.23 e Å3
3 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.023 (5)
Crystal data top
C7H6O5·H2OV = 763.66 (9) Å3
Mr = 188.13Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.7943 (7) ŵ = 0.15 mm1
b = 3.6122 (2) ÅT = 296 K
c = 21.5905 (15) Å0.61 × 0.28 × 0.09 mm
β = 91.268 (6)°
Data collection top
Stoe IPDS 2
diffractometer
1502 independent reflections
Absorption correction: integration
(X-RED32; Stoe & Cie, 2002)
1262 reflections with I > 2σ(I)
Tmin = 0.948, Tmax = 0.986Rint = 0.042
4558 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0393 restraints
wR(F2) = 0.104H atoms treated by a mixture of independent and constrained refinement
S = 1.04Δρmax = 0.15 e Å3
1502 reflectionsΔρmin = 0.23 e Å3
127 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
C10.67337 (16)0.6332 (5)0.58435 (8)0.0369 (4)
H10.63830.70580.54590.044*
C20.81149 (16)0.5670 (5)0.59282 (8)0.0349 (4)
C30.86369 (15)0.4587 (5)0.65029 (8)0.0356 (4)
C40.77763 (17)0.4238 (5)0.70009 (8)0.0395 (4)
C50.63957 (17)0.4863 (5)0.69214 (8)0.0414 (4)
H50.58140.45960.72530.050*
C60.58767 (16)0.5895 (5)0.63421 (8)0.0370 (4)
C70.43925 (16)0.6603 (5)0.62739 (8)0.0408 (4)
O10.90229 (12)0.5986 (4)0.54561 (6)0.0480 (4)
H20.86130.65990.51370.072*
O21.00108 (11)0.3881 (4)0.65588 (6)0.0469 (4)
H31.02000.32650.69160.070*
O30.83973 (12)0.3290 (5)0.75521 (6)0.0546 (4)
H40.78230.31690.78220.082*
O40.35878 (13)0.5981 (5)0.66792 (6)0.0583 (4)
O50.40210 (12)0.7959 (5)0.57298 (6)0.0567 (4)
H60.31930.82920.57190.085*
O60.14365 (13)1.0125 (5)0.56257 (7)0.0499 (4)
H6A0.120 (3)1.147 (8)0.5916 (12)0.102 (11)*
H6B0.077 (4)0.879 (14)0.555 (2)0.24 (3)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0338 (8)0.0434 (9)0.0333 (9)0.0031 (7)0.0022 (7)0.0016 (7)
C20.0310 (8)0.0418 (9)0.0321 (9)0.0009 (7)0.0036 (6)0.0008 (7)
C30.0264 (7)0.0457 (9)0.0346 (9)0.0013 (7)0.0009 (6)0.0010 (7)
C40.0337 (8)0.0530 (11)0.0316 (9)0.0013 (7)0.0021 (6)0.0037 (8)
C50.0322 (8)0.0572 (11)0.0349 (9)0.0039 (7)0.0042 (7)0.0038 (8)
C60.0299 (8)0.0444 (9)0.0367 (9)0.0041 (7)0.0002 (7)0.0001 (7)
C70.0319 (8)0.0525 (10)0.0381 (10)0.0049 (7)0.0003 (7)0.0008 (8)
O10.0361 (6)0.0738 (10)0.0342 (7)0.0052 (6)0.0051 (5)0.0085 (6)
O20.0286 (6)0.0775 (10)0.0345 (7)0.0051 (6)0.0026 (5)0.0035 (6)
O30.0334 (6)0.0984 (12)0.0321 (7)0.0070 (7)0.0005 (5)0.0138 (7)
O40.0335 (6)0.0953 (12)0.0465 (8)0.0101 (7)0.0074 (6)0.0062 (8)
O50.0330 (6)0.0882 (11)0.0488 (8)0.0137 (7)0.0020 (5)0.0158 (7)
O60.0358 (7)0.0697 (9)0.0440 (8)0.0126 (6)0.0016 (5)0.0016 (7)
Geometric parameters (Å, º) top
C1—C21.382 (2)C5—H50.9300
C1—C61.388 (2)C6—C71.480 (2)
C1—H10.9300C7—O41.212 (2)
C2—O11.372 (2)C7—O51.317 (2)
C2—C31.388 (2)O1—H20.8200
C3—O21.3723 (19)O2—H30.8200
C3—C41.387 (2)O3—H40.8200
C4—O31.368 (2)O5—H60.8200
C4—C51.378 (2)O6—H6A0.830 (18)
C5—C61.391 (2)O6—H6B0.824 (19)
C2—C1—C6118.99 (15)C4—C5—H5120.2
C2—C1—H1120.5C6—C5—H5120.2
C6—C1—H1120.5C1—C6—C5120.83 (15)
O1—C2—C1122.41 (14)C1—C6—C7120.83 (15)
O1—C2—C3117.10 (14)C5—C6—C7118.32 (15)
C1—C2—C3120.48 (15)O4—C7—O5122.82 (15)
O2—C3—C4121.78 (14)O4—C7—C6123.32 (16)
O2—C3—C2118.17 (14)O5—C7—C6113.86 (15)
C4—C3—C2120.05 (14)C2—O1—H2109.5
O3—C4—C5124.44 (16)C3—O2—H3109.5
O3—C4—C3115.54 (14)C4—O3—H4109.5
C5—C4—C3120.01 (15)C7—O5—H6109.5
C4—C5—C6119.61 (16)H6A—O6—H6B105 (3)
C6—C1—C2—O1178.97 (16)O3—C4—C5—C6178.56 (18)
C6—C1—C2—C30.0 (3)C3—C4—C5—C60.9 (3)
O1—C2—C3—O20.5 (2)C2—C1—C6—C51.0 (3)
C1—C2—C3—O2178.51 (16)C2—C1—C6—C7179.51 (16)
O1—C2—C3—C4179.56 (16)C4—C5—C6—C10.5 (3)
C1—C2—C3—C41.4 (3)C4—C5—C6—C7179.08 (17)
O2—C3—C4—O32.4 (3)C1—C6—C7—O4173.92 (19)
C2—C3—C4—O3177.66 (17)C5—C6—C7—O47.5 (3)
O2—C3—C4—C5178.04 (17)C1—C6—C7—O55.8 (3)
C2—C3—C4—C51.9 (3)C5—C6—C7—O5172.79 (18)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H3···O30.822.262.7006 (18)114
O5—H6···O60.821.852.6542 (17)167
O1—H2···O6i0.822.032.7539 (19)147
O2—H3···O3ii0.822.523.1721 (19)137
O3—H4···O4iii0.821.942.7154 (19)158
O6—H6A···O2iv0.83 (2)2.03 (2)2.8237 (19)161 (3)
O6—H6B···O1v0.82 (2)2.00 (2)2.814 (2)171 (5)
Symmetry codes: (i) x+1, y+2, z+1; (ii) x+2, y1/2, z+3/2; (iii) x+1, y1/2, z+3/2; (iv) x1, y+1, z; (v) x1, y, z.

Experimental details

Crystal data
Chemical formulaC7H6O5·H2O
Mr188.13
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)9.7943 (7), 3.6122 (2), 21.5905 (15)
β (°) 91.268 (6)
V3)763.66 (9)
Z4
Radiation typeMo Kα
µ (mm1)0.15
Crystal size (mm)0.61 × 0.28 × 0.09
Data collection
DiffractometerStoe IPDS 2
diffractometer
Absorption correctionIntegration
(X-RED32; Stoe & Cie, 2002)
Tmin, Tmax0.948, 0.986
No. of measured, independent and
observed [I > 2σ(I)] reflections
4558, 1502, 1262
Rint0.042
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.104, 1.04
No. of reflections1502
No. of parameters127
No. of restraints3
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.15, 0.23

Computer programs: X-AREA (Stoe & Cie, 2002), X-RED32 (Stoe & Cie, 2002), WinGX (Farrugia, 1997) and SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H3···O30.822.262.7006 (18)114
O5—H6···O60.821.852.6542 (17)167
O1—H2···O6i0.822.032.7539 (19)147
O2—H3···O3ii0.822.523.1721 (19)137
O3—H4···O4iii0.821.942.7154 (19)158
O6—H6A···O2iv0.830 (18)2.03 (2)2.8237 (19)161 (3)
O6—H6B···O1v0.824 (19)2.00 (2)2.814 (2)171 (5)
Symmetry codes: (i) x+1, y+2, z+1; (ii) x+2, y1/2, z+3/2; (iii) x+1, y1/2, z+3/2; (iv) x1, y+1, z; (v) x1, y, z.
Other crystal structures of gallic acid monohydrate (Å, °) top
12
Unit-cell parametersa = 5.794 (4)a = 14.15 (1)
b = 4.719 (5)b = 3.622 (9)
c = 28.688 (5)c = 15.028 (10)
β = 95.08 (3)β = 97.52 (7)
V = 781.4 (3)V = 764 (1)
Space groupMonoclinic, P21/cMonoclinic, P2/n
ReferenceJiang et al. (2000)Okabe et al. (2001)
 

Acknowledgements

The authors thank the Ondokuz Mayıs University Research Fund for financial support of this project (project No. PYO.FEN.1904.09.006).

References

First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
First citationFarrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838.  CrossRef CAS IUCr Journals Google Scholar
First citationGenç, S., Dege, N., Çetin, A., Cansız, A., Şekerci, M. & Dinçer, M. (2004). Acta Cryst. E60, o1580–o1582.  Web of Science CSD CrossRef IUCr Journals Google Scholar
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Volume 67| Part 6| June 2011| Pages o1509-o1510
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