organic compounds
2-(4-Hydroxyphenyl)acetic acid–4,4′-bipyridine (1/1)
aCollege of Chemistry and Life Sciences, Zhejiang Normal University, Jinhua 321004, Zhejiang, People's Republic of China
*Correspondence e-mail: sky53@zjnu.cn
In the acid molecule of the title complex, C10H8N2·C8H8O3, the acetyl C—C—C—O torsion angle is −32.1 (3)°, and in the molecule of the base, the dihedral angle between the two pyridine rings is 23.41 (10)°. In the intermolecular O—H⋯N hydrogen bonds link the acid and the base molecules into a one-dimensional triple-helix framework extended along the b axis.
Related literature
For related functional complexes, see: Han et al. (2009). For hydrogen-bond motif structures, see: Tomura & Yamashita (2001).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2006); cell SAINT (Bruker, 2006); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.
Supporting information
https://doi.org/10.1107/S1600536810018842/pv2281sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810018842/pv2281Isup2.hkl
2-(4-hydroxyphenyl)acetic acid (0.152 g, 1 mmol) and 4,4'-bipyridine (0.156 g, 1 mmol) were added to a mixed solution of ethanol (20 ml) and water (10 ml) with Cu(SO4)2 (0.127 g, 0.5 mmol) under stirred conditions at room temperature. A few minutes later a lot of blue deposit appeared. After the deposit was filtered out, a light blue solution was kept for evaporating. Colorless single crystals of the title complex were obtained about 19 days later.
The H atoms bonded to C atoms were positioned geometrically and refined using a riding model with C—H = 0.93 and 0.97 Å for methylene and aryl H-atoms, respectively and Uiso(H) = 1.2Ueq(C). The H atoms bonded to O atoms were located in a difference Fourier map and refined without restraints.
The design and synthesis of coordination complexes have absorbed considerable attention due to their diverse structures with 4,4'-bipyridine linker (Han et al., 2009). Moreover, hydrogen bond can also play a role in forming motif structures (Tomura & Yamashita, 2001). We have designed the title complex in an attempt to prepare crystaline magnetic materials and report its
in this paper.The structure of the title complex is shown in Fig. 1, which reveals that it contains 2-(4-hydroxyphenyl)acetic acid and 4,4'-bipyridine in a ratio of 1:1. In the molecule of 2-(4-hydroxyphenyl)acetic acid, the acetyl torsion angle C(1)—C(7)—C(8)—O(2) is -32.1 (3) °, and in the molecule of 4,4'-bipyridine, the dihedral angle between the two pyridine rings is 23.41 (10) °. The two molecules arranged in the crystal at regular intervals with two O—H···N hydrogen bonds. The end to end hydrogen-bonding interactions lead to the formation of a one-dimensional triple-helix structure framework along the b-axis, Fig 2. Between adjacent triple-helix chains there exist weak π—π interactions.
For related functional complexes, see: Han et al. (2009). For hydrogen-bond motif structures, see: Tomura & Yamashita (2001).
Data collection: APEX2 (Bruker, 2006); cell
SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).Fig. 1. The molecular structure of the title complex. Displacement ellipsoids are drawn at the 30% probability level. | |
Fig. 2. The packing plot of the complex showing triple-helix chains. |
C10H8N2·C8H8O3 | F(000) = 1296 |
Mr = 308.33 | Dx = 1.311 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 3274 reflections |
a = 25.3578 (6) Å | θ = 1.9–27.7° |
b = 10.2305 (2) Å | µ = 0.09 mm−1 |
c = 14.2546 (4) Å | T = 296 K |
β = 122.321 (2)° | Block, colourless |
V = 3125.03 (15) Å3 | 0.25 × 0.14 × 0.06 mm |
Z = 8 |
Bruker APEXII CCD area-detector diffractometer | 3650 independent reflections |
Radiation source: fine-focus sealed tube | 2128 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.043 |
φ & ω scans | θmax = 27.7°, θmin = 1.9° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −32→32 |
Tmin = 0.984, Tmax = 0.994 | k = −13→13 |
24334 measured reflections | l = −18→18 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.047 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.139 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.06 | w = 1/[σ2(Fo2) + (0.065P)2 + 0.2994P] where P = (Fo2 + 2Fc2)/3 |
3650 reflections | (Δ/σ)max < 0.001 |
214 parameters | Δρmax = 0.15 e Å−3 |
0 restraints | Δρmin = −0.16 e Å−3 |
C10H8N2·C8H8O3 | V = 3125.03 (15) Å3 |
Mr = 308.33 | Z = 8 |
Monoclinic, C2/c | Mo Kα radiation |
a = 25.3578 (6) Å | µ = 0.09 mm−1 |
b = 10.2305 (2) Å | T = 296 K |
c = 14.2546 (4) Å | 0.25 × 0.14 × 0.06 mm |
β = 122.321 (2)° |
Bruker APEXII CCD area-detector diffractometer | 3650 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2128 reflections with I > 2σ(I) |
Tmin = 0.984, Tmax = 0.994 | Rint = 0.043 |
24334 measured reflections |
R[F2 > 2σ(F2)] = 0.047 | 0 restraints |
wR(F2) = 0.139 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.06 | Δρmax = 0.15 e Å−3 |
3650 reflections | Δρmin = −0.16 e Å−3 |
214 parameters |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.54789 (7) | 0.32235 (16) | 0.04851 (15) | 0.0637 (5) | |
C2 | 0.54036 (7) | 0.28856 (15) | 0.13430 (17) | 0.0674 (5) | |
H2A | 0.5211 | 0.2098 | 0.1308 | 0.081* | |
C3 | 0.56064 (8) | 0.36856 (15) | 0.22505 (16) | 0.0624 (5) | |
H3A | 0.5554 | 0.3431 | 0.2822 | 0.075* | |
C4 | 0.58890 (7) | 0.48680 (14) | 0.23132 (14) | 0.0540 (4) | |
C5 | 0.59659 (7) | 0.52233 (14) | 0.14611 (14) | 0.0555 (4) | |
H5A | 0.6156 | 0.6014 | 0.1494 | 0.067* | |
C6 | 0.57611 (8) | 0.44072 (16) | 0.05596 (15) | 0.0618 (4) | |
H6A | 0.5814 | 0.4660 | −0.0011 | 0.074* | |
C7 | 0.52498 (9) | 0.23409 (19) | −0.05088 (17) | 0.0888 (7) | |
H7A | 0.4826 | 0.2074 | −0.0765 | 0.107* | |
H7B | 0.5235 | 0.2843 | −0.1100 | 0.107* | |
C8 | 0.56331 (9) | 0.11343 (17) | −0.03167 (16) | 0.0686 (5) | |
C9 | 0.27818 (7) | 0.03470 (14) | 0.13722 (13) | 0.0531 (4) | |
C10 | 0.24522 (9) | −0.08224 (16) | 0.10478 (15) | 0.0668 (5) | |
H10A | 0.2019 | −0.0821 | 0.0680 | 0.080* | |
C11 | 0.27717 (11) | −0.19771 (17) | 0.12756 (17) | 0.0777 (6) | |
H11A | 0.2543 | −0.2749 | 0.1067 | 0.093* | |
C12 | 0.37044 (10) | −0.09378 (19) | 0.20793 (17) | 0.0780 (6) | |
H12A | 0.4136 | −0.0968 | 0.2423 | 0.094* | |
C13 | 0.34242 (8) | 0.02609 (17) | 0.19086 (15) | 0.0669 (5) | |
H13A | 0.3666 | 0.1015 | 0.2153 | 0.080* | |
C14 | 0.24634 (7) | 0.16282 (14) | 0.11616 (13) | 0.0510 (4) | |
C15 | 0.18450 (8) | 0.17940 (15) | 0.03144 (14) | 0.0600 (4) | |
H15A | 0.1621 | 0.1097 | −0.0147 | 0.072* | |
C16 | 0.15638 (8) | 0.29964 (16) | 0.01587 (15) | 0.0656 (5) | |
H16A | 0.1144 | 0.3078 | −0.0394 | 0.079* | |
C17 | 0.24598 (9) | 0.38940 (16) | 0.15596 (15) | 0.0657 (5) | |
H17A | 0.2678 | 0.4619 | 0.1983 | 0.079* | |
C18 | 0.27730 (8) | 0.27190 (15) | 0.17954 (14) | 0.0616 (4) | |
H18A | 0.3188 | 0.2660 | 0.2375 | 0.074* | |
N1 | 0.33881 (9) | −0.20646 (15) | 0.17762 (14) | 0.0809 (5) | |
N2 | 0.18645 (7) | 0.40479 (13) | 0.07623 (12) | 0.0636 (4) | |
O1 | 0.54120 (7) | 0.01483 (14) | −0.08188 (14) | 0.1052 (6) | |
O2 | 0.62304 (6) | 0.12757 (12) | 0.04163 (12) | 0.0847 (5) | |
H2O | 0.6456 (10) | 0.046 (2) | 0.0532 (17) | 0.102* | |
O3 | 0.60808 (6) | 0.56199 (12) | 0.32305 (11) | 0.0733 (4) | |
H3O | 0.6234 (10) | 0.635 (2) | 0.3150 (17) | 0.088* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0446 (9) | 0.0533 (9) | 0.0674 (12) | 0.0112 (7) | 0.0128 (8) | −0.0090 (8) |
C2 | 0.0489 (10) | 0.0440 (9) | 0.0873 (13) | −0.0055 (7) | 0.0218 (9) | −0.0050 (9) |
C3 | 0.0525 (10) | 0.0557 (9) | 0.0743 (12) | −0.0072 (7) | 0.0308 (9) | 0.0034 (8) |
C4 | 0.0497 (9) | 0.0439 (8) | 0.0632 (11) | −0.0009 (6) | 0.0266 (8) | −0.0024 (7) |
C5 | 0.0510 (9) | 0.0436 (8) | 0.0665 (11) | −0.0021 (6) | 0.0279 (8) | 0.0006 (7) |
C6 | 0.0531 (10) | 0.0616 (10) | 0.0626 (11) | 0.0104 (7) | 0.0255 (9) | 0.0015 (8) |
C7 | 0.0684 (13) | 0.0733 (12) | 0.0792 (13) | 0.0164 (10) | 0.0090 (10) | −0.0249 (10) |
C8 | 0.0630 (12) | 0.0584 (10) | 0.0692 (12) | 0.0031 (8) | 0.0252 (10) | −0.0127 (9) |
C9 | 0.0596 (10) | 0.0485 (8) | 0.0501 (9) | 0.0060 (7) | 0.0286 (8) | 0.0056 (7) |
C10 | 0.0709 (12) | 0.0541 (10) | 0.0711 (12) | 0.0042 (8) | 0.0350 (10) | 0.0022 (8) |
C11 | 0.0991 (16) | 0.0501 (10) | 0.0807 (13) | 0.0072 (10) | 0.0461 (12) | 0.0066 (9) |
C12 | 0.0722 (13) | 0.0720 (13) | 0.0792 (13) | 0.0231 (10) | 0.0333 (11) | 0.0192 (10) |
C13 | 0.0621 (11) | 0.0595 (10) | 0.0687 (12) | 0.0107 (8) | 0.0280 (10) | 0.0110 (8) |
C14 | 0.0547 (9) | 0.0484 (8) | 0.0533 (9) | 0.0038 (7) | 0.0311 (8) | 0.0066 (7) |
C15 | 0.0599 (10) | 0.0501 (9) | 0.0636 (11) | 0.0012 (7) | 0.0288 (9) | −0.0005 (8) |
C16 | 0.0555 (10) | 0.0618 (10) | 0.0669 (11) | 0.0091 (8) | 0.0243 (9) | 0.0035 (9) |
C17 | 0.0690 (12) | 0.0540 (9) | 0.0680 (11) | 0.0023 (8) | 0.0325 (10) | −0.0062 (8) |
C18 | 0.0562 (10) | 0.0567 (9) | 0.0624 (11) | 0.0022 (7) | 0.0253 (9) | −0.0027 (8) |
N1 | 0.1009 (14) | 0.0620 (10) | 0.0767 (11) | 0.0285 (9) | 0.0454 (10) | 0.0179 (8) |
N2 | 0.0656 (10) | 0.0546 (8) | 0.0665 (9) | 0.0094 (7) | 0.0327 (8) | −0.0004 (7) |
O1 | 0.0818 (10) | 0.0680 (9) | 0.1354 (14) | −0.0077 (7) | 0.0376 (9) | −0.0416 (9) |
O2 | 0.0640 (9) | 0.0596 (7) | 0.0937 (10) | 0.0124 (6) | 0.0175 (8) | −0.0179 (7) |
O3 | 0.0921 (10) | 0.0576 (7) | 0.0738 (8) | −0.0186 (6) | 0.0467 (8) | −0.0124 (6) |
C1—C2 | 1.379 (3) | C10—C11 | 1.370 (2) |
C1—C6 | 1.382 (2) | C10—H10A | 0.9300 |
C1—C7 | 1.510 (2) | C11—N1 | 1.330 (2) |
C2—C3 | 1.377 (2) | C11—H11A | 0.9300 |
C2—H2A | 0.9300 | C12—N1 | 1.337 (3) |
C3—C4 | 1.384 (2) | C12—C13 | 1.372 (2) |
C3—H3A | 0.9300 | C12—H12A | 0.9300 |
C4—O3 | 1.3631 (19) | C13—H13A | 0.9300 |
C4—C5 | 1.378 (2) | C14—C18 | 1.385 (2) |
C5—C6 | 1.380 (2) | C14—C15 | 1.386 (2) |
C5—H5A | 0.9300 | C15—C16 | 1.379 (2) |
C6—H6A | 0.9300 | C15—H15A | 0.9300 |
C7—C8 | 1.503 (2) | C16—N2 | 1.333 (2) |
C7—H7A | 0.9700 | C16—H16A | 0.9300 |
C7—H7B | 0.9700 | C17—N2 | 1.327 (2) |
C8—O1 | 1.190 (2) | C17—C18 | 1.380 (2) |
C8—O2 | 1.309 (2) | C17—H17A | 0.9300 |
C9—C13 | 1.384 (2) | C18—H18A | 0.9300 |
C9—C10 | 1.389 (2) | O2—H2O | 0.97 (2) |
C9—C14 | 1.484 (2) | O3—H3O | 0.87 (2) |
C2—C1—C6 | 117.60 (16) | C11—C10—H10A | 120.3 |
C2—C1—C7 | 121.07 (18) | C9—C10—H10A | 120.3 |
C6—C1—C7 | 121.33 (19) | N1—C11—C10 | 124.19 (18) |
C3—C2—C1 | 121.66 (16) | N1—C11—H11A | 117.9 |
C3—C2—H2A | 119.2 | C10—C11—H11A | 117.9 |
C1—C2—H2A | 119.2 | N1—C12—C13 | 123.29 (19) |
C2—C3—C4 | 120.03 (17) | N1—C12—H12A | 118.4 |
C2—C3—H3A | 120.0 | C13—C12—H12A | 118.4 |
C4—C3—H3A | 120.0 | C12—C13—C9 | 119.99 (17) |
O3—C4—C5 | 123.41 (14) | C12—C13—H13A | 120.0 |
O3—C4—C3 | 117.52 (16) | C9—C13—H13A | 120.0 |
C5—C4—C3 | 119.07 (15) | C18—C14—C15 | 116.89 (14) |
C4—C5—C6 | 120.07 (14) | C18—C14—C9 | 121.49 (14) |
C4—C5—H5A | 120.0 | C15—C14—C9 | 121.61 (14) |
C6—C5—H5A | 120.0 | C16—C15—C14 | 119.74 (16) |
C5—C6—C1 | 121.56 (17) | C16—C15—H15A | 120.1 |
C5—C6—H6A | 119.2 | C14—C15—H15A | 120.1 |
C1—C6—H6A | 119.2 | N2—C16—C15 | 123.21 (16) |
C8—C7—C1 | 115.68 (15) | N2—C16—H16A | 118.4 |
C8—C7—H7A | 108.4 | C15—C16—H16A | 118.4 |
C1—C7—H7A | 108.4 | N2—C17—C18 | 123.72 (16) |
C8—C7—H7B | 108.4 | N2—C17—H17A | 118.1 |
C1—C7—H7B | 108.4 | C18—C17—H17A | 118.1 |
H7A—C7—H7B | 107.4 | C17—C18—C14 | 119.42 (16) |
O1—C8—O2 | 123.08 (17) | C17—C18—H18A | 120.3 |
O1—C8—C7 | 122.41 (17) | C14—C18—H18A | 120.3 |
O2—C8—C7 | 114.47 (15) | C11—N1—C12 | 116.44 (15) |
C13—C9—C10 | 116.75 (15) | C17—N2—C16 | 116.96 (14) |
C13—C9—C14 | 121.38 (14) | C8—O2—H2O | 111.5 (12) |
C10—C9—C14 | 121.87 (15) | C4—O3—H3O | 108.1 (14) |
C11—C10—C9 | 119.30 (18) | ||
C6—C1—C2—C3 | −0.7 (2) | N1—C12—C13—C9 | −1.8 (3) |
C7—C1—C2—C3 | −179.55 (15) | C10—C9—C13—C12 | 1.1 (3) |
C1—C2—C3—C4 | 0.6 (2) | C14—C9—C13—C12 | −179.22 (16) |
C2—C3—C4—O3 | −179.97 (15) | C13—C9—C14—C18 | −23.0 (2) |
C2—C3—C4—C5 | −0.3 (2) | C10—C9—C14—C18 | 156.71 (16) |
O3—C4—C5—C6 | 179.78 (14) | C13—C9—C14—C15 | 156.28 (16) |
C3—C4—C5—C6 | 0.2 (2) | C10—C9—C14—C15 | −24.1 (2) |
C4—C5—C6—C1 | −0.2 (2) | C18—C14—C15—C16 | −1.8 (2) |
C2—C1—C6—C5 | 0.5 (2) | C9—C14—C15—C16 | 178.93 (15) |
C7—C1—C6—C5 | 179.37 (15) | C14—C15—C16—N2 | 2.6 (3) |
C2—C1—C7—C8 | −74.3 (2) | N2—C17—C18—C14 | 1.4 (3) |
C6—C1—C7—C8 | 106.8 (2) | C15—C14—C18—C17 | −0.1 (2) |
C1—C7—C8—O1 | 150.2 (2) | C9—C14—C18—C17 | 179.18 (15) |
C1—C7—C8—O2 | −32.1 (3) | C10—C11—N1—C12 | 0.9 (3) |
C13—C9—C10—C11 | 0.4 (3) | C13—C12—N1—C11 | 0.8 (3) |
C14—C9—C10—C11 | −179.26 (16) | C18—C17—N2—C16 | −0.7 (3) |
C9—C10—C11—N1 | −1.5 (3) | C15—C16—N2—C17 | −1.3 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2O···N2i | 0.97 (2) | 1.71 (2) | 2.679 (2) | 179 (2) |
O3—H3O···N1ii | 0.87 (2) | 1.86 (2) | 2.728 (2) | 171 (2) |
Symmetry codes: (i) x+1/2, y−1/2, z; (ii) −x+1, y+1, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C10H8N2·C8H8O3 |
Mr | 308.33 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 296 |
a, b, c (Å) | 25.3578 (6), 10.2305 (2), 14.2546 (4) |
β (°) | 122.321 (2) |
V (Å3) | 3125.03 (15) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.25 × 0.14 × 0.06 |
Data collection | |
Diffractometer | Bruker APEXII CCD area-detector |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.984, 0.994 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 24334, 3650, 2128 |
Rint | 0.043 |
(sin θ/λ)max (Å−1) | 0.654 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.047, 0.139, 1.06 |
No. of reflections | 3650 |
No. of parameters | 214 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.15, −0.16 |
Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2O···N2i | 0.97 (2) | 1.71 (2) | 2.679 (2) | 179 (2) |
O3—H3O···N1ii | 0.87 (2) | 1.86 (2) | 2.728 (2) | 171 (2) |
Symmetry codes: (i) x+1/2, y−1/2, z; (ii) −x+1, y+1, −z+1/2. |
References
Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Han, L., Zhou, Y., Wang, X. T., Li, X. & Tong, M. L. (2009). J. Mol. Struct. 923, 24–27. Web of Science CSD CrossRef CAS Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Tomura, M. & Yamashita, Y. (2001). Chem. Lett. 30, 532–533. Web of Science CSD CrossRef Google Scholar
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The design and synthesis of coordination complexes have absorbed considerable attention due to their diverse structures with 4,4'-bipyridine linker (Han et al., 2009). Moreover, hydrogen bond can also play a role in forming motif structures (Tomura & Yamashita, 2001). We have designed the title complex in an attempt to prepare crystaline magnetic materials and report its crystal structure in this paper.
The structure of the title complex is shown in Fig. 1, which reveals that it contains 2-(4-hydroxyphenyl)acetic acid and 4,4'-bipyridine in a ratio of 1:1. In the molecule of 2-(4-hydroxyphenyl)acetic acid, the acetyl torsion angle C(1)—C(7)—C(8)—O(2) is -32.1 (3) °, and in the molecule of 4,4'-bipyridine, the dihedral angle between the two pyridine rings is 23.41 (10) °. The two molecules arranged in the crystal at regular intervals with two O—H···N hydrogen bonds. The end to end hydrogen-bonding interactions lead to the formation of a one-dimensional triple-helix structure framework along the b-axis, Fig 2. Between adjacent triple-helix chains there exist weak π—π interactions.