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

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ISSN: 2056-9890

2-Hydr­­oxy-3-meth­oxy­benzoic acid monohydrate

aSchool of Chemistry and Environment, South China Normal University, Guangzhou 510006, People's Republic of China
*Correspondence e-mail: zhqfang77@yahoo.com.cn

(Received 2 January 2008; accepted 5 March 2008; online 12 March 2008)

The asymmetric unit of the title compound, C8H8O4·H2O, contains two organic mol­ecules which are connected by the two water mol­ecules through O—H⋯O hydrogen bonds, forming an R44(12) ring. Further O—H⋯O hydrogen bonds assemble these rings through R66(18) rings, giving rise to infinite helical chains arranged around the b axis. These helical chains are assembled by offset ππ stacking inter­actions [centroid–centroid distance = 3.6432 (8) Å] between the aromatic rings of neigboring chains, forming a supra­molecular network.

Related literature

For related literature, see: Kozlevcar et al. (2006[Kozlevcar, B., Odlazek, D., Golobic, A., Pevec, A., Strauch, P. & Segedin, P. (2006). Polyhedron, 25, 1161-1166.]); Moncol et al. (2006[Moncol, J., Púčeková, Z., Lis, T. & Valigura, D. (2006). Acta Cryst. E62, m448-m450.]); Liu et al. (2007[Liu, Z.-H., Qiu, Y.-C., Li, Y.-H., Zeng, R.-H. & Deng, H. (2007). Acta Cryst. E63, o2616-o2617.]); Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]); Etter et al. (1990[Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256-262.]).

[Scheme 1]

Experimental

Crystal data
  • C8H8O4·H2O

  • Mr = 186.16

  • Monoclinic, P 21 /c

  • a = 17.9642 (4) Å

  • b = 14.5225 (3) Å

  • c = 6.8864 (2) Å

  • β = 91.770 (1)°

  • V = 1795.70 (8) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 296 (2) K

  • 0.30 × 0.25 × 0.20 mm

Data collection
  • Bruker APEXII area-detector diffractometer

  • Absorption correction: none

  • 17337 measured reflections

  • 4111 independent reflections

  • 2658 reflections with I > 2σ(I)

  • Rint = 0.026

Refinement
  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.110

  • S = 1.04

  • 4111 reflections

  • 241 parameters

  • H-atom parameters constrained

  • Δρmax = 0.12 e Å−3

  • Δρmin = −0.17 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2⋯O3 0.82 1.90 2.6142 (14) 144
O4—H4A⋯O2W 0.82 1.77 2.5634 (16) 164
O5—H5A⋯O1W 0.82 1.78 2.5763 (16) 165
O7—H7⋯O6 0.82 1.88 2.5946 (14) 145
O1W—H1W⋯O3 0.85 1.96 2.8082 (16) 171
O2W—H4W⋯O6 0.85 1.97 2.8071 (16) 170
O1W—H2W⋯O1i 0.84 2.11 2.8741 (17) 150
O1W—H2W⋯O2i 0.84 2.49 3.1930 (16) 141
O2W—H3W⋯O8ii 0.84 2.13 2.8866 (19) 149
O2W—H3W⋯O7ii 0.84 2.33 3.0331 (15) 141
Symmetry codes: (i) -x+1, -y+1, -z; (ii) -x+2, -y+1, -z.

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2 and SMART. Bruker AXS Inc, Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2004[Bruker (2004). APEX2 and SMART. Bruker AXS Inc, Madison, Wisconsin, USA.]); data reduction: SAINT; 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: ORTEPIII (Burnett & Johnson, 1996[Burnett, M. N. & Johnson, C. K. (1996). ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.]), ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Comment top

Hydrogen-bonding interactions between ligands are specific and directional. In this sense, 2-hydroxy-3-methoxybenzoic acid is an excellent candidate for the construction of supramolecular complexes, which have multiple coordination modes and form regular hydrogen bonds functioning as both a hydrogen-bond donor and acceptor (Kozlevcar et al., 2006, Liu et al., 2007, Moncol et al., 2006). Recently, we obtained the title compound of (I) under hydrothermal condition.

The asymmetric unit of the title compound (I) contains two molecules which are connected by the water molecules trough O—H···O hydrogen bonds building up a R44(12) ring (Etter et al., 1990; Bernstein et al., 1995) (Table 1, Fig. 1). The C—C and C—O distances ranging from 1.225 (2) to 1.425 (2) Å, show no remarkable features. These rings are further connected to each other by O—H···O hydrogen bonds buiding a R66 (18) ring to form helical chains arranged around the [0 1/2 0] axis (Table 1, Fig. 2). These helical chains are further assembled through offset π-π stacking interactions between the aromatic rings of neigboring chains (centroid to centroid distance of 3.6432 (8) Å [Symmetry code: 1 - x,1 - y,-1 - z]; interplanar distance of 3.44 Å and slippest distances of 1.20 Å) to form a supramolecular network.

Related literature top

For related literature, see: Kozlevcar et al. (2006); Moncol et al. (2006); Liu et al. (2007); Bernstein et al. (1995); Etter et al. (1990).

Experimental top

2-Hydroxy-3-methoxybenzoic acid was dissolved in hot water with stirring. Colorless single crystals suitable for X-ray diffraction were obtained at room temperature by slow evaporation of the solvent over a period of several days.

Refinement top

H atoms on 2-hydroxy-3-methoxybenzoic acid were placed at calculated positions and were treated as riding on the parent C atoms with C—H = 0.93 Å (aromatic ring) or 0.96 Å (methyl group), O—H = 0.82 Å (hydroxyl and carboxylate groups) and with Uiso(H) = 1.2 or 1.5 Ueq(C, O). Water H atoms were tentatively located in difference Fourier maps and were refined with distance restraints of O–H = 0.85 Å and H···H = 1.39 Å, each within a standard deviation of 0.01 Å, and with Uiso(H) = 1.5 Ueq(O). In the last stage of refinement, the H attached to water molecule were treated as riding on their parent O atoms.

Computing details top

Data collection: APEXII (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure showing the atomic-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H bonds are shown as dashed lines. H atoms are represented as small spheres of arbitrary radii.
[Figure 2] Fig. 2. Partial packing view showing the intermolecular hydrogen bonding interactions as dashed lines. H atoms not involved in hydrogen bondings have been omitted for clarity. [Symmetry codes: (I) 1 - x, 1 - y, -z; (ii) 2 - x, 1 - y, -z]
2-Hydroxy-3-methoxybenzoic acid monohydrate top
Crystal data top
C8H8O4·H2OF(000) = 784
Mr = 186.16Dx = 1.377 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3600 reflections
a = 17.9642 (4) Åθ = 1.4–28.0°
b = 14.5225 (3) ŵ = 0.12 mm1
c = 6.8864 (2) ÅT = 296 K
β = 91.770 (1)°Block, colorless
V = 1795.70 (8) Å30.30 × 0.25 × 0.20 mm
Z = 8
Data collection top
Bruker APEXII area-detector
diffractometer
2658 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.026
Graphite monochromatorθmax = 27.5°, θmin = 1.1°
ϕ and ω scansh = 2323
17337 measured reflectionsk = 1816
4111 independent reflectionsl = 88
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)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.110H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0466P)2 + 0.2399P]
where P = (Fo2 + 2Fc2)/3
4111 reflections(Δ/σ)max = 0.001
241 parametersΔρmax = 0.12 e Å3
0 restraintsΔρmin = 0.17 e Å3
Crystal data top
C8H8O4·H2OV = 1795.70 (8) Å3
Mr = 186.16Z = 8
Monoclinic, P21/cMo Kα radiation
a = 17.9642 (4) ŵ = 0.12 mm1
b = 14.5225 (3) ÅT = 296 K
c = 6.8864 (2) Å0.30 × 0.25 × 0.20 mm
β = 91.770 (1)°
Data collection top
Bruker APEXII area-detector
diffractometer
2658 reflections with I > 2σ(I)
17337 measured reflectionsRint = 0.026
4111 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.110H-atom parameters constrained
S = 1.04Δρmax = 0.12 e Å3
4111 reflectionsΔρmin = 0.17 e Å3
241 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
C10.32586 (10)0.67219 (16)0.6058 (3)0.0809 (6)
H1A0.32100.63770.72440.121*
H1B0.33910.73460.63470.121*
H1C0.27940.67140.54060.121*
C20.45420 (8)0.63558 (10)0.5448 (2)0.0460 (4)
C30.47543 (9)0.66626 (11)0.7236 (2)0.0549 (4)
H30.43960.68690.81380.066*
C40.54984 (9)0.66664 (11)0.7702 (2)0.0560 (4)
H40.56380.68740.89150.067*
C50.60295 (9)0.63668 (11)0.6385 (2)0.0515 (4)
H50.65280.63670.67110.062*
C60.58266 (8)0.60588 (10)0.4548 (2)0.0428 (3)
C70.50804 (8)0.60518 (10)0.4073 (2)0.0414 (3)
C80.63923 (8)0.57528 (11)0.3100 (2)0.0498 (4)
C90.86646 (8)0.35192 (11)0.1597 (2)0.0455 (4)
C100.92233 (7)0.27809 (10)0.16407 (19)0.0399 (3)
C110.90153 (9)0.18508 (10)0.1659 (2)0.0498 (4)
H110.85140.16910.16810.060*
C120.95461 (10)0.11785 (11)0.1646 (2)0.0555 (4)
H120.94040.05630.16470.067*
C131.02955 (10)0.14065 (12)0.1631 (2)0.0550 (4)
H131.06530.09430.16280.066*
C141.05131 (8)0.23114 (11)0.1620 (2)0.0464 (4)
C150.99746 (8)0.30129 (10)0.1617 (2)0.0400 (3)
C161.18105 (11)0.19618 (16)0.1478 (4)0.0897 (7)
H16A1.18240.15850.26230.135*
H16B1.22790.22720.13660.135*
H16C1.17200.15820.03540.135*
O10.38246 (5)0.63195 (9)0.48365 (16)0.0625 (3)
O20.48284 (5)0.57751 (8)0.23382 (15)0.0536 (3)
H20.51800.55960.16480.080*
O30.62337 (6)0.54527 (9)0.15029 (17)0.0642 (3)
O40.70797 (6)0.58220 (11)0.36507 (19)0.0769 (4)
H4A0.73650.56860.27420.115*
O50.79730 (6)0.32376 (8)0.1628 (2)0.0676 (4)
H5A0.76940.36840.16240.101*
O60.88288 (6)0.43402 (8)0.15148 (17)0.0549 (3)
O71.02269 (5)0.38892 (7)0.15833 (16)0.0502 (3)
H70.98720.42450.15100.075*
O81.12298 (6)0.26247 (8)0.16093 (18)0.0635 (3)
O1W0.69046 (7)0.44218 (10)0.1525 (2)0.0860 (5)
H1W0.67380.47800.06330.129*
H2W0.65570.43070.22870.129*
O2W0.81581 (7)0.55507 (10)0.1193 (2)0.0943 (5)
H3W0.84860.59570.13360.141*
H4W0.83090.51880.02990.141*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0531 (11)0.1004 (17)0.0885 (14)0.0254 (10)0.0105 (9)0.0183 (12)
C20.0432 (8)0.0408 (9)0.0540 (9)0.0038 (7)0.0006 (7)0.0023 (7)
C30.0601 (10)0.0499 (10)0.0543 (10)0.0075 (8)0.0055 (8)0.0082 (8)
C40.0676 (11)0.0505 (10)0.0502 (9)0.0019 (8)0.0068 (8)0.0091 (7)
C50.0490 (9)0.0484 (10)0.0575 (10)0.0037 (7)0.0098 (7)0.0030 (7)
C60.0417 (8)0.0371 (8)0.0497 (8)0.0026 (6)0.0019 (6)0.0015 (6)
C70.0440 (8)0.0338 (8)0.0464 (8)0.0013 (6)0.0027 (6)0.0009 (6)
C80.0412 (8)0.0511 (10)0.0570 (10)0.0026 (7)0.0017 (7)0.0022 (8)
C90.0425 (8)0.0477 (10)0.0460 (8)0.0029 (7)0.0014 (6)0.0013 (7)
C100.0445 (8)0.0391 (8)0.0360 (7)0.0014 (6)0.0006 (6)0.0010 (6)
C110.0559 (9)0.0446 (10)0.0486 (9)0.0072 (7)0.0033 (7)0.0038 (7)
C120.0756 (12)0.0376 (9)0.0529 (9)0.0016 (8)0.0031 (8)0.0041 (7)
C130.0683 (11)0.0469 (10)0.0498 (9)0.0154 (8)0.0030 (8)0.0028 (7)
C140.0469 (8)0.0511 (10)0.0411 (8)0.0069 (7)0.0031 (6)0.0021 (7)
C150.0451 (8)0.0403 (9)0.0346 (7)0.0007 (6)0.0007 (6)0.0004 (6)
C160.0574 (12)0.0963 (18)0.1162 (18)0.0313 (11)0.0147 (11)0.0095 (13)
O10.0400 (6)0.0788 (9)0.0686 (7)0.0130 (5)0.0003 (5)0.0157 (6)
O20.0429 (6)0.0693 (8)0.0487 (6)0.0036 (5)0.0049 (5)0.0124 (5)
O30.0484 (6)0.0880 (9)0.0562 (7)0.0054 (6)0.0007 (5)0.0164 (6)
O40.0377 (6)0.1133 (11)0.0795 (9)0.0058 (7)0.0002 (6)0.0279 (8)
O50.0390 (6)0.0566 (8)0.1071 (10)0.0032 (5)0.0005 (6)0.0053 (7)
O60.0484 (6)0.0409 (7)0.0751 (8)0.0013 (5)0.0012 (5)0.0016 (5)
O70.0420 (6)0.0414 (7)0.0670 (7)0.0031 (5)0.0010 (5)0.0005 (5)
O80.0418 (6)0.0673 (8)0.0816 (8)0.0115 (5)0.0084 (5)0.0044 (6)
O1W0.0604 (8)0.1133 (12)0.0857 (9)0.0343 (7)0.0227 (7)0.0390 (8)
O2W0.0522 (7)0.0961 (11)0.1329 (13)0.0188 (7)0.0272 (8)0.0534 (9)
Geometric parameters (Å, º) top
C1—O11.4247 (19)C10—C111.402 (2)
C1—H1A0.9600C11—C121.365 (2)
C1—H1B0.9600C11—H110.9300
C1—H1C0.9600C12—C131.387 (2)
C2—O11.3692 (17)C12—H120.9300
C2—C31.374 (2)C13—C141.371 (2)
C2—C71.4036 (19)C13—H130.9300
C3—C41.384 (2)C14—O81.3657 (18)
C3—H30.9300C14—C151.405 (2)
C4—C51.367 (2)C15—O71.3514 (17)
C4—H40.9300C16—O81.425 (2)
C5—C61.401 (2)C16—H16A0.9600
C5—H50.9300C16—H16B0.9600
C6—C71.3895 (19)C16—H16C0.9600
C6—C81.470 (2)O2—H20.8200
C7—O21.3520 (17)O4—H4A0.8200
C8—O31.2250 (19)O5—H5A0.8200
C8—O41.3067 (18)O7—H70.8200
C9—O61.2299 (18)O1W—H1W0.8516
C9—O51.3088 (17)O1W—H2W0.8440
C9—C101.468 (2)O2W—H3W0.8422
C10—C151.3916 (19)O2W—H4W0.8477
O1—C1—H1A109.5C15—C10—C9119.05 (13)
O1—C1—H1B109.5C11—C10—C9121.44 (13)
H1A—C1—H1B109.5C12—C11—C10120.19 (15)
O1—C1—H1C109.5C12—C11—H11119.9
H1A—C1—H1C109.5C10—C11—H11119.9
H1B—C1—H1C109.5C11—C12—C13120.51 (15)
O1—C2—C3125.31 (13)C11—C12—H12119.7
O1—C2—C7114.58 (13)C13—C12—H12119.7
C3—C2—C7120.11 (14)C14—C13—C12120.39 (15)
C2—C3—C4120.36 (14)C14—C13—H13119.8
C2—C3—H3119.8C12—C13—H13119.8
C4—C3—H3119.8O8—C14—C13126.03 (14)
C5—C4—C3120.29 (15)O8—C14—C15114.06 (14)
C5—C4—H4119.9C13—C14—C15119.91 (14)
C3—C4—H4119.9O7—C15—C10123.65 (13)
C4—C5—C6120.33 (15)O7—C15—C14116.84 (13)
C4—C5—H5119.8C10—C15—C14119.50 (13)
C6—C5—H5119.8O8—C16—H16A109.5
C7—C6—C5119.62 (13)O8—C16—H16B109.5
C7—C6—C8119.36 (13)H16A—C16—H16B109.5
C5—C6—C8121.01 (13)O8—C16—H16C109.5
O2—C7—C6124.17 (12)H16A—C16—H16C109.5
O2—C7—C2116.55 (13)H16B—C16—H16C109.5
C6—C7—C2119.27 (14)C2—O1—C1117.63 (13)
O3—C8—O4122.41 (14)C7—O2—H2109.5
O3—C8—C6122.77 (14)C8—O4—H4A109.5
O4—C8—C6114.82 (14)C9—O5—H5A109.5
O6—C9—O5122.19 (14)C15—O7—H7109.5
O6—C9—C10122.96 (13)C14—O8—C16117.88 (15)
O5—C9—C10114.85 (14)H1W—O1W—H2W108.6
C15—C10—C11119.49 (13)H3W—O2W—H4W108.1
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O30.821.902.6142 (14)144
O4—H4A···O2W0.821.772.5634 (16)164
O5—H5A···O1W0.821.782.5763 (16)165
O7—H7···O60.821.882.5946 (14)145
O1W—H1W···O30.851.962.8082 (16)171
O2W—H4W···O60.851.972.8071 (16)170
O1W—H2W···O1i0.842.112.8741 (17)150
O1W—H2W···O2i0.842.493.1930 (16)141
O2W—H3W···O8ii0.842.132.8866 (19)149
O2W—H3W···O7ii0.842.333.0331 (15)141
Symmetry codes: (i) x+1, y+1, z; (ii) x+2, y+1, z.

Experimental details

Crystal data
Chemical formulaC8H8O4·H2O
Mr186.16
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)17.9642 (4), 14.5225 (3), 6.8864 (2)
β (°) 91.770 (1)
V3)1795.70 (8)
Z8
Radiation typeMo Kα
µ (mm1)0.12
Crystal size (mm)0.30 × 0.25 × 0.20
Data collection
DiffractometerBruker APEXII area-detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
17337, 4111, 2658
Rint0.026
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.110, 1.04
No. of reflections4111
No. of parameters241
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.12, 0.17

Computer programs: APEXII (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2003), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O30.821.902.6142 (14)144.2
O4—H4A···O2W0.821.772.5634 (16)164.0
O5—H5A···O1W0.821.782.5763 (16)164.7
O7—H7···O60.821.882.5946 (14)145.0
O1W—H1W···O30.851.962.8082 (16)170.9
O2W—H4W···O60.851.972.8071 (16)169.6
O1W—H2W···O1i0.842.112.8741 (17)150.2
O1W—H2W···O2i0.842.493.1930 (16)140.9
O2W—H3W···O8ii0.842.132.8866 (19)149.1
O2W—H3W···O7ii0.842.333.0331 (15)140.7
Symmetry codes: (i) x+1, y+1, z; (ii) x+2, y+1, z.
 

Acknowledgements

The authors acknowledge South China Normal University for supporting this work.

References

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