organic compounds
4-Aminobenzoic acid–quinoline (1/1)
aResearch and Development Centre, Bharathiyar University, Coimbatore 641 046, India, Department of Physics, CPCL Polytechnic College, Chennai 600 068, India, bDepartment of Physics, Alagappa University, Karaikkudi 630 003, India, cDepartment of Physics, The American College, Madurai 625 002, India, and dDepartment of Physics, CPCL Polytechnic College, Chennai 600 068, India
*Correspondence e-mail: israel.samuel@gmail.com, chakkaravarthi_2005@yahoo.com
In the title 1:1 adduct, C9H7N·C7H7NO2, the carboxyl group is twisted at an angle of 5.42 (8) Å with respect to its attached benzene ring. In the crystal, the carboxylic acid molecule is linked to the quinoline molecule by an O—H⋯N hydrogen bond. The 4-aminobenzoic acid molecules are linked by N—H⋯O hydrogen bonds, forming sheets propagating in (001). Weak aromatic π–π stacking [centroid-to-centroid distances = 3.758 (1) and 3.888 (1) Å] interactions also occur.
Keywords: crystal structure; quinoline derivative; 4-aminobenzoic acid; hydrogen bonding; π–π stacking.
CCDC reference: 1473449
Structure description
Quinoline derivatives are known to exhibit pharmacological activities such as anti-viral (Font et al., 1997) and anti-inflammatory (Sloboda et al., 1991). As part of our studies in this area, we now describe the synthesis and structure of the title adduct (Fig. 1), which contains one quinoline and one 4-aminobenzoic acid molecule in the The quinoline ring system (N1/C8–C16) is almost planar with a maximum deviation of 0.0133 (13) Å for atom N1. In the 4-aminobenzoic acid molecule, the carboxyl group is twisted at an angle of 5.42 (8) Å to the attached benzene ring. The geometric parameters are comparable with similar structures (Divya Bharathi et al., 2015; Li & Chai, 2007; Song et al., 2011).
In the crystal, the 4-aminobenzoic acid molecules are linked by N—H⋯O hydrogen bonds (Table 1), forming zigzag sheets propagating in the (001) plane (Fig. 2). The quinoline molecule accepts an O—H⋯N hydrogen bond (Table 1) from the 4-aminobenzoic acid molecule, and lies pendant to the (001) sheets (Fig. 2). The is also influenced by weak π–π interactions [Cg3⋯Cg2i = 3.888 (1) Å; Cg3⋯Cg3i = 3.758 (1) Å; symmetry code: (i) 1 − x, −y, 1 − z; Cg2 and Cg3 are the centroids of the (N2/C8–C11/C16) and (C11–C16) rings, respectively].
Synthesis and crystallization
Quinoline (1.29 g)and 4-aminobenzoic acid (1.37 g) in an equimolar ratio (1:1) were mixed in acetone and the mixture was stirred for 4 h. The solution was filtered and kept at room temperature. Colourless blocks were obtained by slow evaporation.
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2Structural data
CCDC reference: 1473449
10.1107/S2414314616006040/hb4033sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S2414314616006040/hb4033Isup2.hkl
Supporting information file. DOI: 10.1107/S2414314616006040/hb4033Isup3.cml
Quinoline (1.29 g)and 4-aminobenzoic acid (1.37 g) in an equimolar ratio (1:1) were mixed in acetone and the mixture was stirred for 4 h. The solution was filtered and kept at room temperature. Colourless blocks were obtained by slow evaporation.
Quinoline derivatives are known to exhibit pharmacological activities such as anti-viral (Font et al., 1997) and anti-inflammatory (Sloboda et al., 1991). As part of our studies in this area, we now describe the synthesis and structure of the title adduct (Fig. 1), which contains one quinoline and one 4-aminobenzoic acid molecule in the
The quinoline ring system (N1/C8–C16) is almost planar with a maximum deviation of 0.0133 (13) Å for atom N1. In the 4-aminobenzoic acid molecule, the carboxyl group is twisted at an angle of 5.42 (8) Å to the attached benzene ring. The geometric parameters are comparable with similar structures (Divya Bharathi et al., 2015; Li & Chai, 2007; Song et al., 2011).In the crystal, the 4-aminobenzoic acid molecules are linked by N—H···O hydrogen bonds (Table 1), forming zigzag sheets propagating in the (001) plane (Fig. 2). The quinoline molecule accepts an O—H···N hydrogen bond (Table 1) from the 4-aminobenzoic acid molecule, and lies pendant to the (001) sheets (Fig. 2). The π–π interactions [Cg3···Cg2i = 3.888 (1) Å; Cg3···Cg3i = 3.758 (1) Å; symmetry code: (i) 1 - x, -y, 1 - z; Cg2 and Cg3 are the centroids of the (N2/C8–C11/C16) and (C11–C16) rings, respectively].
is also influenced by weakData collection: APEX2 (Bruker, 2004); cell
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: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).Fig. 1. The molecular structure, with 30% probability displacement ellipsoids for non-H atoms. | |
Fig. 2. The crystal packing of the title compound viewed along the b axis. The hydrogen bonds are shown as dashed lines (see Table 1), and C-bound H atoms have been omitted for clarity. |
C9H7N·C7H7NO2 | F(000) = 560 |
Mr = 266.29 | Dx = 1.288 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 4104 reflections |
a = 7.6842 (7) Å | θ = 2.6–25.6° |
b = 8.1013 (6) Å | µ = 0.09 mm−1 |
c = 22.0669 (16) Å | T = 295 K |
β = 90.893 (3)° | Block, colourless |
V = 1373.54 (19) Å3 | 0.24 × 0.20 × 0.18 mm |
Z = 4 |
Bruker Kappa APEXII CCD diffractometer | 3616 independent reflections |
Radiation source: fine-focus sealed tube | 2427 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.025 |
ω and φ scan | θmax = 28.9°, θmin = 2.7° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −10→10 |
Tmin = 0.980, Tmax = 0.985 | k = −10→11 |
16394 measured reflections | l = −30→29 |
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)] = 0.044 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.117 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0402P)2 + 0.3668P] where P = (Fo2 + 2Fc2)/3 |
3616 reflections | (Δ/σ)max < 0.001 |
184 parameters | Δρmax = 0.21 e Å−3 |
1 restraint | Δρmin = −0.19 e Å−3 |
C9H7N·C7H7NO2 | V = 1373.54 (19) Å3 |
Mr = 266.29 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.6842 (7) Å | µ = 0.09 mm−1 |
b = 8.1013 (6) Å | T = 295 K |
c = 22.0669 (16) Å | 0.24 × 0.20 × 0.18 mm |
β = 90.893 (3)° |
Bruker Kappa APEXII CCD diffractometer | 3616 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 2427 reflections with I > 2σ(I) |
Tmin = 0.980, Tmax = 0.985 | Rint = 0.025 |
16394 measured reflections |
R[F2 > 2σ(F2)] = 0.044 | 1 restraint |
wR(F2) = 0.117 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.21 e Å−3 |
3616 reflections | Δρmin = −0.19 e Å−3 |
184 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 > 2sigma(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 | 0.24265 (18) | 0.44594 (17) | 0.31360 (6) | 0.0376 (3) | |
C2 | 0.09036 (18) | 0.41448 (19) | 0.28042 (6) | 0.0426 (3) | |
H2 | −0.0152 | 0.4538 | 0.2946 | 0.051* | |
C3 | 0.09303 (18) | 0.32657 (19) | 0.22717 (6) | 0.0442 (3) | |
H3 | −0.0102 | 0.3083 | 0.2057 | 0.053* | |
C4 | 0.24935 (19) | 0.26426 (18) | 0.20497 (6) | 0.0402 (3) | |
C5 | 0.40228 (18) | 0.29667 (18) | 0.23807 (6) | 0.0429 (3) | |
H5 | 0.5080 | 0.2571 | 0.2241 | 0.052* | |
C6 | 0.39846 (18) | 0.38607 (17) | 0.29087 (6) | 0.0408 (3) | |
H6 | 0.5020 | 0.4071 | 0.3119 | 0.049* | |
C7 | 0.23461 (18) | 0.53452 (18) | 0.37202 (6) | 0.0404 (3) | |
C8 | 0.7831 (2) | 0.3218 (2) | 0.46278 (8) | 0.0548 (4) | |
H8 | 0.8725 | 0.3851 | 0.4796 | 0.066* | |
C9 | 0.8106 (2) | 0.2457 (2) | 0.40693 (8) | 0.0594 (4) | |
H9 | 0.9157 | 0.2591 | 0.3872 | 0.071* | |
C10 | 0.6829 (2) | 0.1524 (2) | 0.38192 (7) | 0.0563 (4) | |
H10 | 0.7000 | 0.0999 | 0.3450 | 0.068* | |
C11 | 0.5234 (2) | 0.13473 (18) | 0.41201 (6) | 0.0445 (3) | |
C12 | 0.3816 (3) | 0.0413 (2) | 0.38928 (8) | 0.0615 (5) | |
H12 | 0.3913 | −0.0137 | 0.3525 | 0.074* | |
C13 | 0.2319 (3) | 0.0311 (2) | 0.42048 (9) | 0.0675 (5) | |
H13 | 0.1398 | −0.0316 | 0.4052 | 0.081* | |
C14 | 0.2149 (2) | 0.1137 (2) | 0.47528 (8) | 0.0610 (5) | |
H14 | 0.1108 | 0.1065 | 0.4961 | 0.073* | |
C15 | 0.3476 (2) | 0.2045 (2) | 0.49891 (7) | 0.0508 (4) | |
H15 | 0.3343 | 0.2586 | 0.5357 | 0.061* | |
C16 | 0.50510 (19) | 0.21711 (17) | 0.46791 (6) | 0.0397 (3) | |
N1 | 0.25232 (17) | 0.17624 (18) | 0.15233 (6) | 0.0558 (4) | |
H1A | 0.1573 | 0.1584 | 0.1323 | 0.067* | |
H1B | 0.3493 | 0.1386 | 0.1391 | 0.067* | |
N2 | 0.63746 (16) | 0.30866 (15) | 0.49269 (5) | 0.0464 (3) | |
O1 | 0.09822 (14) | 0.57684 (16) | 0.39513 (5) | 0.0575 (3) | |
O2 | 0.38721 (13) | 0.56351 (14) | 0.39791 (5) | 0.0494 (3) | |
H2A | 0.373 (2) | 0.601 (2) | 0.4336 (5) | 0.074* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0362 (7) | 0.0386 (7) | 0.0381 (7) | −0.0014 (6) | −0.0026 (6) | 0.0029 (6) |
C2 | 0.0330 (7) | 0.0511 (9) | 0.0437 (7) | 0.0013 (6) | 0.0006 (6) | −0.0017 (6) |
C3 | 0.0341 (7) | 0.0558 (9) | 0.0424 (7) | −0.0015 (6) | −0.0047 (6) | −0.0025 (7) |
C4 | 0.0412 (8) | 0.0427 (8) | 0.0367 (7) | −0.0022 (6) | 0.0017 (6) | 0.0037 (6) |
C5 | 0.0345 (7) | 0.0460 (8) | 0.0484 (8) | 0.0029 (6) | 0.0038 (6) | 0.0019 (6) |
C6 | 0.0339 (7) | 0.0420 (8) | 0.0462 (8) | −0.0017 (6) | −0.0056 (6) | 0.0036 (6) |
C7 | 0.0367 (8) | 0.0440 (8) | 0.0405 (7) | −0.0037 (6) | −0.0042 (6) | 0.0032 (6) |
C8 | 0.0449 (9) | 0.0584 (10) | 0.0608 (10) | −0.0089 (8) | −0.0043 (7) | 0.0052 (8) |
C9 | 0.0484 (10) | 0.0710 (11) | 0.0592 (10) | 0.0040 (9) | 0.0111 (8) | 0.0126 (9) |
C10 | 0.0646 (11) | 0.0587 (10) | 0.0458 (8) | 0.0125 (9) | 0.0051 (8) | 0.0006 (7) |
C11 | 0.0510 (9) | 0.0401 (8) | 0.0421 (7) | 0.0041 (7) | −0.0054 (6) | 0.0027 (6) |
C12 | 0.0739 (13) | 0.0531 (10) | 0.0569 (10) | −0.0033 (9) | −0.0150 (9) | −0.0105 (8) |
C13 | 0.0606 (12) | 0.0613 (11) | 0.0799 (12) | −0.0163 (9) | −0.0195 (10) | −0.0010 (10) |
C14 | 0.0435 (9) | 0.0697 (11) | 0.0698 (11) | −0.0090 (8) | −0.0025 (8) | 0.0098 (9) |
C15 | 0.0462 (9) | 0.0590 (10) | 0.0472 (8) | −0.0025 (8) | 0.0000 (7) | −0.0002 (7) |
C16 | 0.0406 (8) | 0.0388 (7) | 0.0394 (7) | 0.0010 (6) | −0.0060 (6) | 0.0045 (6) |
N1 | 0.0437 (7) | 0.0776 (10) | 0.0461 (7) | 0.0009 (7) | 0.0035 (6) | −0.0152 (7) |
N2 | 0.0425 (7) | 0.0499 (7) | 0.0465 (7) | −0.0051 (6) | −0.0051 (5) | −0.0010 (6) |
O1 | 0.0384 (6) | 0.0846 (9) | 0.0494 (6) | 0.0027 (6) | −0.0029 (5) | −0.0158 (6) |
O2 | 0.0383 (6) | 0.0654 (7) | 0.0444 (6) | −0.0057 (5) | −0.0045 (5) | −0.0092 (5) |
C1—C6 | 1.3924 (19) | C9—H9 | 0.9300 |
C1—C2 | 1.3941 (19) | C10—C11 | 1.410 (2) |
C1—C7 | 1.4777 (19) | C10—H10 | 0.9300 |
C2—C3 | 1.3745 (19) | C11—C16 | 1.412 (2) |
C2—H2 | 0.9300 | C11—C12 | 1.413 (2) |
C3—C4 | 1.3986 (19) | C12—C13 | 1.352 (3) |
C3—H3 | 0.9300 | C12—H12 | 0.9300 |
C4—N1 | 1.3635 (18) | C13—C14 | 1.390 (3) |
C4—C5 | 1.3987 (19) | C13—H13 | 0.9300 |
C5—C6 | 1.373 (2) | C14—C15 | 1.355 (2) |
C5—H5 | 0.9300 | C14—H14 | 0.9300 |
C6—H6 | 0.9300 | C15—C16 | 1.403 (2) |
C7—O1 | 1.2217 (17) | C15—H15 | 0.9300 |
C7—O2 | 1.3174 (17) | C16—N2 | 1.3660 (18) |
C8—N2 | 1.3122 (19) | N1—H1A | 0.8600 |
C8—C9 | 1.397 (2) | N1—H1B | 0.8600 |
C8—H8 | 0.9300 | O2—H2A | 0.852 (9) |
C9—C10 | 1.350 (2) | ||
C6—C1—C2 | 117.81 (13) | C9—C10—C11 | 119.72 (15) |
C6—C1—C7 | 122.09 (13) | C9—C10—H10 | 120.1 |
C2—C1—C7 | 120.05 (13) | C11—C10—H10 | 120.1 |
C3—C2—C1 | 121.34 (13) | C10—C11—C16 | 117.59 (14) |
C3—C2—H2 | 119.3 | C10—C11—C12 | 123.95 (15) |
C1—C2—H2 | 119.3 | C16—C11—C12 | 118.47 (15) |
C2—C3—C4 | 120.72 (13) | C13—C12—C11 | 120.66 (16) |
C2—C3—H3 | 119.6 | C13—C12—H12 | 119.7 |
C4—C3—H3 | 119.6 | C11—C12—H12 | 119.7 |
N1—C4—C3 | 120.86 (13) | C12—C13—C14 | 120.35 (16) |
N1—C4—C5 | 121.19 (13) | C12—C13—H13 | 119.8 |
C3—C4—C5 | 117.94 (13) | C14—C13—H13 | 119.8 |
C6—C5—C4 | 120.89 (13) | C15—C14—C13 | 121.07 (17) |
C6—C5—H5 | 119.6 | C15—C14—H14 | 119.5 |
C4—C5—H5 | 119.6 | C13—C14—H14 | 119.5 |
C5—C6—C1 | 121.29 (13) | C14—C15—C16 | 120.09 (15) |
C5—C6—H6 | 119.4 | C14—C15—H15 | 120.0 |
C1—C6—H6 | 119.4 | C16—C15—H15 | 120.0 |
O1—C7—O2 | 122.18 (13) | N2—C16—C15 | 119.13 (13) |
O1—C7—C1 | 123.24 (13) | N2—C16—C11 | 121.51 (14) |
O2—C7—C1 | 114.58 (12) | C15—C16—C11 | 119.36 (14) |
N2—C8—C9 | 123.36 (16) | C4—N1—H1A | 120.0 |
N2—C8—H8 | 118.3 | C4—N1—H1B | 120.0 |
C9—C8—H8 | 118.3 | H1A—N1—H1B | 120.0 |
C10—C9—C8 | 119.26 (16) | C8—N2—C16 | 118.56 (13) |
C10—C9—H9 | 120.4 | C7—O2—H2A | 109.7 (13) |
C8—C9—H9 | 120.4 | ||
C6—C1—C2—C3 | 0.3 (2) | C9—C10—C11—C16 | 0.0 (2) |
C7—C1—C2—C3 | −177.33 (13) | C9—C10—C11—C12 | 179.34 (16) |
C1—C2—C3—C4 | 0.7 (2) | C10—C11—C12—C13 | −179.45 (16) |
C2—C3—C4—N1 | 179.65 (14) | C16—C11—C12—C13 | −0.1 (2) |
C2—C3—C4—C5 | −1.1 (2) | C11—C12—C13—C14 | 0.5 (3) |
N1—C4—C5—C6 | 179.67 (14) | C12—C13—C14—C15 | −0.6 (3) |
C3—C4—C5—C6 | 0.4 (2) | C13—C14—C15—C16 | 0.3 (3) |
C4—C5—C6—C1 | 0.7 (2) | C14—C15—C16—N2 | −179.68 (15) |
C2—C1—C6—C5 | −1.0 (2) | C14—C15—C16—C11 | 0.2 (2) |
C7—C1—C6—C5 | 176.59 (13) | C10—C11—C16—N2 | −1.0 (2) |
C6—C1—C7—O1 | −174.12 (14) | C12—C11—C16—N2 | 179.57 (14) |
C2—C1—C7—O1 | 3.5 (2) | C10—C11—C16—C15 | 179.15 (14) |
C6—C1—C7—O2 | 5.29 (19) | C12—C11—C16—C15 | −0.3 (2) |
C2—C1—C7—O2 | −177.13 (13) | C9—C8—N2—C16 | −0.6 (2) |
N2—C8—C9—C10 | −0.5 (3) | C15—C16—N2—C8 | −178.85 (14) |
C8—C9—C10—C11 | 0.8 (3) | C11—C16—N2—C8 | 1.3 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O1i | 0.86 | 2.15 | 2.9855 (17) | 164 |
N1—H1B···O2ii | 0.86 | 2.28 | 3.1355 (17) | 175 |
O2—H2A···N2iii | 0.85 (1) | 1.79 (1) | 2.6364 (16) | 174 (2) |
Symmetry codes: (i) −x, y−1/2, −z+1/2; (ii) −x+1, y−1/2, −z+1/2; (iii) −x+1, −y+1, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O1i | 0.86 | 2.15 | 2.9855 (17) | 164 |
N1—H1B···O2ii | 0.86 | 2.28 | 3.1355 (17) | 175 |
O2—H2A···N2iii | 0.852 (9) | 1.787 (10) | 2.6364 (16) | 174.2 (19) |
Symmetry codes: (i) −x, y−1/2, −z+1/2; (ii) −x+1, y−1/2, −z+1/2; (iii) −x+1, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C9H7N·C7H7NO2 |
Mr | 266.29 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 295 |
a, b, c (Å) | 7.6842 (7), 8.1013 (6), 22.0669 (16) |
β (°) | 90.893 (3) |
V (Å3) | 1373.54 (19) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.24 × 0.20 × 0.18 |
Data collection | |
Diffractometer | Bruker Kappa APEXII CCD |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.980, 0.985 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 16394, 3616, 2427 |
Rint | 0.025 |
(sin θ/λ)max (Å−1) | 0.680 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.044, 0.117, 1.03 |
No. of reflections | 3616 |
No. of parameters | 184 |
No. of restraints | 1 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.21, −0.19 |
Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).
Acknowledgements
The authors acknowledge the SAIF, IIT, Madras, for the data collection.
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