organic compounds
of 4,4′-dimethoxy-2,2′-bipyridine
aDepartment of Chemistry, Graduate School of Science and Engineering, Saitama University, Shimo-Okubo 255, Sakura-ku, Saitama 338-8570, Japan, and bComprehensive Analysis Center for Science, Saitama University, Shimo-Okubo 255, Sakura-ku, Saitama 338-8570, Japan
*Correspondence e-mail: fuji@chem.saitama-u.ac.jp
In the title compound, C12H12N2O2, the dihedral angle between the planes of the two pyridine rings is 5.8 (1)°. Neighbouring molecules are linked via C(Me)—H⋯N interactions, generating a two-dimensional sheet structure; C—H⋯π interactions further link the molecules into a three-dimensional network. An overlapped arrangement of parallel pyridine rings in neighbouring molecules [centroid-to-centroid distance = 3.6655 (15) Å] is observed in the crystal structure.
Keywords: crystal structure.
CCDC reference: 1414484
1. Related literature
For related structure of 4,4′-substituted 2,2′-bipyridines, see: Merritt & Schroeder (1956); Tynan et al. (2003); Pearson et al. (2004); Haberecht et al. (2005); Fujihara et al. (2005). For hydrogen-bonded motifs, see: Etter et al. (1990); Bernstein et al. (1995).
2. Experimental
2.1. Crystal data
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Data collection: APEX2 (Bruker, 2014); cell SAINT (Bruker, 2014); data reduction: SAINT and XPREP (Bruker, 2014); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: XCIF (Bruker, 2014).
Supporting information
CCDC reference: 1414484
https://doi.org/10.1107/S2056989015013985/xu5860sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015013985/xu5860Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989015013985/xu5860Isup3.cml
The molecular structure of title compound (I) is illustrated in Fig. 1. In the crystal, all bond lengths and angles are similar to those of the other similar 4,4'-substituted 2,2'-bipyridines (Merritt & Schroeder, 1956; Tynan et al., 2003; Pearson et al., 2004; Haberecht et al., 2005; Fujihara et al., 2005). The dihedral angle between two pyridine rings is 5.8 (1)°. The neighbouring molecules are linked via intermolecular C–H···N interactions with an R22(16) ring motif (Etter et al., 1990; Bernstein et al., 1995), generating 2D sheet structure as shown in Fig. 2. An overlapped arrangement of parallel pyridine rings in neighbouring molecules [centroid-centroid distance = 3.6655 (15) Å] is observed in the π interactions link the molecules into a three-dimensional network, as shown in Fig. 3.
Furthermore, intermolecular C–H···Crystals of (I) suitable for X-ray diffraction were obtained from solutions in acetone of a commercially available sample (Aldrich) by slow evaporation at 298 K. 1H NMR (500MHz, CDCl3): δ 4.10 (s, 6H, -OCH3), 7.03(dd, 2H, py-5H), 8.37(d, 2H, py-H3), 8.56(d, 2H, py-H6).
The molecular structure of title compound (I) is illustrated in Fig. 1. In the crystal, all bond lengths and angles are similar to those of the other similar 4,4'-substituted 2,2'-bipyridines (Merritt & Schroeder, 1956; Tynan et al., 2003; Pearson et al., 2004; Haberecht et al., 2005; Fujihara et al., 2005). The dihedral angle between two pyridine rings is 5.8 (1)°. The neighbouring molecules are linked via intermolecular C–H···N interactions with an R22(16) ring motif (Etter et al., 1990; Bernstein et al., 1995), generating 2D sheet structure as shown in Fig. 2. An overlapped arrangement of parallel pyridine rings in neighbouring molecules [centroid-centroid distance = 3.6655 (15) Å] is observed in the π interactions link the molecules into a three-dimensional network, as shown in Fig. 3.
Furthermore, intermolecular C–H···For related structure of 4,4'-substituted 2,2'-bipyridines, see: Merritt & Schroeder (1956); Tynan et al. (2003); Pearson et al. (2004); Haberecht et al. (2005); Fujihara et al. (2005). For hydrogen-bonded motifs, see: Etter et al. (1990); Bernstein et al. (1995).
Crystals of (I) suitable for X-ray diffraction were obtained from solutions in acetone of a commercially available sample (Aldrich) by slow evaporation at 298 K. 1H NMR (500MHz, CDCl3): δ 4.10 (s, 6H, -OCH3), 7.03(dd, 2H, py-5H), 8.37(d, 2H, py-H3), 8.56(d, 2H, py-H6).
detailsThe H atoms were included in calculated positions and treated as riding atoms: C—H = 0.95-0.98Å with Uiso(H) = 1.5Ueq(C) for methyl H atoms and = 1.2Ueq(C) for aromatic H atoms.
Data collection: APEX2 (Bruker, 2014); cell
SAINT (Bruker, 2014); data reduction: SAINT and XPREP (Bruker2014); program(s) used to solve structure: SHELXL2014 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: XCIF (Bruker, 2014).Fig. 1. The molecular structure of the title compound, showing the atom labelling. Displacement ellipsoids are drawn at the 50% probability level. | |
Fig. 2. Part of the crystal structure of compound (I) showing the formation of 2D sheet. Dashed lines indicate the intermolecular C-H···N interactions. [Symmetry code: (i) x, y, 1+ z; (ii) x, y, -1+ z.] | |
Fig. 3. Part of the crystal structure showing the intersheet stacking interactions and the weak C-H···π hydrogen bonds. |
C12H12N2O2 | F(000) = 228 |
Mr = 216.24 | Dx = 1.369 Mg m−3 |
Monoclinic, P21 | Mo Kα radiation, λ = 0.71073 Å |
a = 6.4235 (11) Å | Cell parameters from 3527 reflections |
b = 10.8139 (18) Å | θ = 2.7–28.3° |
c = 8.0123 (14) Å | µ = 0.10 mm−1 |
β = 109.462 (2)° | T = 200 K |
V = 524.76 (16) Å3 | Plate, colourless |
Z = 2 | 0.24 × 0.07 × 0.05 mm |
Bruker APEXII CCD area-detector diffractometer | 2301 independent reflections |
Radiation source: Bruker TXS fine-focus rotating anode | 2155 reflections with I > 2σ(I) |
Bruker Helios multilayer confocal mirror monochromator | Rint = 0.014 |
Detector resolution: 8.333 pixels mm-1 | θmax = 27.1°, θmin = 2.7° |
φ and ω scans | h = −8→8 |
Absorption correction: multi-scan (SADABS2014; Bruker, 2014) | k = −13→13 |
l = −10→10 | |
5925 measured reflections |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.033 | w = 1/[σ2(Fo2) + (0.038P)2 + 0.1642P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.084 | (Δ/σ)max < 0.001 |
S = 1.01 | Δρmax = 0.20 e Å−3 |
2301 reflections | Δρmin = −0.16 e Å−3 |
147 parameters | Absolute structure: Flack x determined using 976 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013) |
1 restraint | Absolute structure parameter: 0.7 (3) |
C12H12N2O2 | V = 524.76 (16) Å3 |
Mr = 216.24 | Z = 2 |
Monoclinic, P21 | Mo Kα radiation |
a = 6.4235 (11) Å | µ = 0.10 mm−1 |
b = 10.8139 (18) Å | T = 200 K |
c = 8.0123 (14) Å | 0.24 × 0.07 × 0.05 mm |
β = 109.462 (2)° |
Bruker APEXII CCD area-detector diffractometer | 2301 independent reflections |
Absorption correction: multi-scan (SADABS2014; Bruker, 2014) | 2155 reflections with I > 2σ(I) |
Rint = 0.014 | |
5925 measured reflections |
R[F2 > 2σ(F2)] = 0.033 | H-atom parameters constrained |
wR(F2) = 0.084 | Δρmax = 0.20 e Å−3 |
S = 1.01 | Δρmin = −0.16 e Å−3 |
2301 reflections | Absolute structure: Flack x determined using 976 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013) |
147 parameters | Absolute structure parameter: 0.7 (3) |
1 restraint |
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. Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane) - 3.4311 (0.0049) x + 8.4883 (0.0065) y - 0.9456 (0.0066) z = 4.1170 (0.0067) * -0.0041 (0.0014) N2 * 0.0008 (0.0014) C6 * 0.0044 (0.0014) C7 * -0.0064 (0.0014) C8 * 0.0031 (0.0015) C9 * 0.0021 (0.0016) C10 -0.0086 (0.0030) O2 -0.0684 (0.0042) C12 Rms deviation of fitted atoms = 0.0039 - 3.4675 (0.0048) x + 8.7970 (0.0059) y - 0.1939 (0.0067) z = 4.4232 (0.0036) Angle to previous plane (with approximate esd) = 5.832 ( 0.127 ) * 0.0007 (0.0014) N1 * 0.0006 (0.0016) C1 * -0.0022 (0.0015) C2 * 0.0024 (0.0015) C3 * -0.0011 (0.0013) C4 * -0.0005 (0.0013) C5 0.0002 (0.0030) O1 -0.0031 (0.0045) C11 Rms deviation of fitted atoms = 0.0015 - 3.4311 (0.0049) x + 8.4883 (0.0065) y - 0.9456 (0.0066) z = 4.1170 (0.0067) Angle to previous plane (with approximate esd) = 5.832 ( 0.127 ) * -0.0041 (0.0014) N2 * 0.0008 (0.0014) C6 * 0.0044 (0.0014) C7 * -0.0064 (0.0014) C8 * 0.0031 (0.0015) C9 * 0.0021 (0.0016) C10 -3.3185 (0.0031) N1_$4 -3.3333 (0.0027) C1_$4 -3.4592 (0.0024) C2_$4 -3.5727 (0.0026) C3_$4 -3.5648 (0.0032) C4_$4 -3.4354 (0.0034) C5_$4 Rms deviation of fitted atoms = 0.0039 - 3.4675 (0.0048) x + 8.7970 (0.0059) y - 0.1939 (0.0067) z = 4.4232 (0.0036) Angle to previous plane (with approximate esd) = 5.832 ( 0.127 ) * 0.0007 (0.0014) N1 * 0.0006 (0.0016) C1 * -0.0022 (0.0015) C2 * 0.0024 (0.0015) C3 * -0.0011 (0.0013) C4 * -0.0005 (0.0013) C5 3.5634 (0.0029) N2_$3 3.4535 (0.0033) C6_$3 3.3280 (0.0034) C7_$3 3.3037 (0.0027) C8_$3 3.4295 (0.0025) C9_$3 3.5529 (0.0027) C10_$3 Rms deviation of fitted atoms = 0.0015 |
x | y | z | Uiso*/Ueq | ||
C1 | −0.1486 (3) | 0.4462 (2) | 0.0875 (3) | 0.0267 (5) | |
H1 | −0.2534 | 0.4031 | −0.0068 | 0.032* | |
C2 | −0.1727 (4) | 0.4400 (2) | 0.2528 (3) | 0.0266 (5) | |
H2 | −0.2892 | 0.3940 | 0.2711 | 0.032* | |
C3 | −0.0204 (3) | 0.5037 (2) | 0.3910 (3) | 0.0229 (4) | |
C4 | 0.1487 (3) | 0.56915 (19) | 0.3571 (3) | 0.0236 (4) | |
H4 | 0.2556 | 0.6130 | 0.4492 | 0.028* | |
C5 | 0.1577 (3) | 0.56905 (19) | 0.1864 (3) | 0.0221 (4) | |
C6 | 0.3359 (3) | 0.63676 (19) | 0.1424 (3) | 0.0217 (4) | |
C7 | 0.3547 (4) | 0.6263 (2) | −0.0241 (3) | 0.0238 (4) | |
H7 | 0.2539 | 0.5768 | −0.1126 | 0.029* | |
C8 | 0.5240 (4) | 0.68943 (19) | −0.0599 (3) | 0.0235 (4) | |
C9 | 0.6663 (4) | 0.7627 (2) | 0.0716 (3) | 0.0268 (5) | |
H9 | 0.7823 | 0.8081 | 0.0514 | 0.032* | |
C10 | 0.6319 (4) | 0.7668 (2) | 0.2337 (3) | 0.0295 (5) | |
H10 | 0.7293 | 0.8166 | 0.3239 | 0.035* | |
C11 | −0.1939 (4) | 0.4392 (3) | 0.5974 (3) | 0.0356 (6) | |
H11A | −0.3380 | 0.4719 | 0.5251 | 0.053* | |
H11B | −0.1765 | 0.4482 | 0.7230 | 0.053* | |
H11C | −0.1846 | 0.3515 | 0.5698 | 0.053* | |
C12 | 0.7110 (4) | 0.7348 (2) | −0.2653 (3) | 0.0321 (5) | |
H12A | 0.7009 | 0.8244 | −0.2509 | 0.048* | |
H12B | 0.7005 | 0.7164 | −0.3876 | 0.048* | |
H12C | 0.8526 | 0.7048 | −0.1844 | 0.048* | |
N1 | 0.0100 (3) | 0.50795 (19) | 0.0503 (2) | 0.0244 (4) | |
N2 | 0.4729 (3) | 0.70612 (19) | 0.2732 (2) | 0.0275 (4) | |
O1 | −0.0221 (3) | 0.50643 (16) | 0.5595 (2) | 0.0307 (4) | |
O2 | 0.5337 (3) | 0.67463 (15) | −0.2257 (2) | 0.0304 (4) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0250 (10) | 0.0285 (11) | 0.0256 (10) | −0.0048 (10) | 0.0069 (8) | −0.0029 (9) |
C2 | 0.0252 (10) | 0.0274 (11) | 0.0292 (11) | −0.0049 (10) | 0.0118 (9) | −0.0023 (10) |
C3 | 0.0256 (10) | 0.0222 (10) | 0.0227 (10) | 0.0027 (9) | 0.0105 (8) | 0.0002 (9) |
C4 | 0.0224 (10) | 0.0225 (10) | 0.0242 (11) | −0.0003 (8) | 0.0055 (8) | −0.0007 (9) |
C5 | 0.0210 (9) | 0.0208 (10) | 0.0248 (10) | 0.0015 (8) | 0.0082 (8) | 0.0014 (8) |
C6 | 0.0201 (10) | 0.0196 (10) | 0.0252 (10) | 0.0019 (8) | 0.0071 (8) | 0.0017 (8) |
C7 | 0.0229 (10) | 0.0234 (10) | 0.0250 (10) | −0.0012 (8) | 0.0077 (8) | −0.0016 (8) |
C8 | 0.0239 (10) | 0.0239 (11) | 0.0235 (10) | 0.0023 (9) | 0.0090 (8) | 0.0024 (8) |
C9 | 0.0244 (10) | 0.0279 (11) | 0.0296 (11) | −0.0040 (9) | 0.0112 (9) | 0.0018 (9) |
C10 | 0.0267 (11) | 0.0338 (13) | 0.0267 (11) | −0.0074 (9) | 0.0071 (9) | −0.0046 (9) |
C11 | 0.0397 (13) | 0.0443 (14) | 0.0292 (12) | −0.0120 (12) | 0.0200 (10) | −0.0030 (11) |
C12 | 0.0345 (12) | 0.0370 (13) | 0.0287 (12) | −0.0063 (10) | 0.0158 (10) | 0.0006 (10) |
N1 | 0.0241 (8) | 0.0265 (9) | 0.0229 (9) | −0.0015 (7) | 0.0081 (7) | −0.0003 (7) |
N2 | 0.0257 (9) | 0.0321 (10) | 0.0252 (9) | −0.0040 (8) | 0.0091 (7) | −0.0014 (8) |
O1 | 0.0333 (8) | 0.0362 (9) | 0.0254 (8) | −0.0085 (7) | 0.0137 (6) | −0.0025 (7) |
O2 | 0.0325 (9) | 0.0366 (9) | 0.0256 (8) | −0.0094 (7) | 0.0144 (7) | −0.0042 (7) |
C1—N1 | 1.332 (3) | C8—O2 | 1.359 (3) |
C1—C2 | 1.385 (3) | C8—C9 | 1.390 (3) |
C1—H1 | 0.9500 | C9—C10 | 1.389 (3) |
C2—C3 | 1.391 (3) | C9—H9 | 0.9500 |
C2—H2 | 0.9500 | C10—N2 | 1.338 (3) |
C3—O1 | 1.354 (3) | C10—H10 | 0.9500 |
C3—C4 | 1.398 (3) | C11—O1 | 1.436 (3) |
C4—C5 | 1.388 (3) | C11—H11A | 0.9800 |
C4—H4 | 0.9500 | C11—H11B | 0.9800 |
C5—N1 | 1.355 (3) | C11—H11C | 0.9800 |
C5—C6 | 1.496 (2) | C12—O2 | 1.436 (3) |
C6—N2 | 1.349 (3) | C12—H12A | 0.9800 |
C6—C7 | 1.384 (3) | C12—H12B | 0.9800 |
C7—C8 | 1.393 (3) | C12—H12C | 0.9800 |
C7—H7 | 0.9500 | ||
N1—C1—C2 | 125.1 (2) | C9—C8—C7 | 119.02 (19) |
N1—C1—H1 | 117.4 | C10—C9—C8 | 117.2 (2) |
C2—C1—H1 | 117.4 | C10—C9—H9 | 121.4 |
C1—C2—C3 | 117.7 (2) | C8—C9—H9 | 121.4 |
C1—C2—H2 | 121.2 | N2—C10—C9 | 125.3 (2) |
C3—C2—H2 | 121.2 | N2—C10—H10 | 117.4 |
O1—C3—C2 | 124.60 (19) | C9—C10—H10 | 117.4 |
O1—C3—C4 | 116.61 (18) | O1—C11—H11A | 109.5 |
C2—C3—C4 | 118.79 (19) | O1—C11—H11B | 109.5 |
C5—C4—C3 | 118.80 (18) | H11A—C11—H11B | 109.5 |
C5—C4—H4 | 120.6 | O1—C11—H11C | 109.5 |
C3—C4—H4 | 120.6 | H11A—C11—H11C | 109.5 |
N1—C5—C4 | 123.02 (19) | H11B—C11—H11C | 109.5 |
N1—C5—C6 | 115.79 (17) | O2—C12—H12A | 109.5 |
C4—C5—C6 | 121.18 (17) | O2—C12—H12B | 109.5 |
N2—C6—C7 | 123.39 (19) | H12A—C12—H12B | 109.5 |
N2—C6—C5 | 116.19 (17) | O2—C12—H12C | 109.5 |
C7—C6—C5 | 120.41 (17) | H12A—C12—H12C | 109.5 |
C6—C7—C8 | 118.92 (19) | H12B—C12—H12C | 109.5 |
C6—C7—H7 | 120.5 | C1—N1—C5 | 116.58 (18) |
C8—C7—H7 | 120.5 | C10—N2—C6 | 116.14 (19) |
O2—C8—C9 | 125.1 (2) | C3—O1—C11 | 117.47 (18) |
O2—C8—C7 | 115.88 (18) | C8—O2—C12 | 117.40 (17) |
N1—C1—C2—C3 | 0.3 (4) | C6—C7—C8—C9 | −1.1 (3) |
C1—C2—C3—O1 | −180.0 (2) | O2—C8—C9—C10 | −179.9 (2) |
C1—C2—C3—C4 | −0.5 (3) | C7—C8—C9—C10 | 1.0 (3) |
O1—C3—C4—C5 | 179.94 (18) | C8—C9—C10—N2 | −0.1 (4) |
C2—C3—C4—C5 | 0.4 (3) | C2—C1—N1—C5 | −0.1 (3) |
C3—C4—C5—N1 | −0.2 (3) | C4—C5—N1—C1 | 0.0 (3) |
C3—C4—C5—C6 | −179.56 (19) | C6—C5—N1—C1 | 179.41 (18) |
N1—C5—C6—N2 | 174.7 (2) | C9—C10—N2—C6 | −0.5 (4) |
C4—C5—C6—N2 | −5.8 (3) | C7—C6—N2—C10 | 0.4 (3) |
N1—C5—C6—C7 | −5.5 (3) | C5—C6—N2—C10 | −179.92 (19) |
C4—C5—C6—C7 | 173.9 (2) | C2—C3—O1—C11 | −0.2 (3) |
N2—C6—C7—C8 | 0.4 (3) | C4—C3—O1—C11 | −179.7 (2) |
C5—C6—C7—C8 | −179.28 (17) | C9—C8—O2—C12 | 3.0 (3) |
C6—C7—C8—O2 | 179.70 (18) | C7—C8—O2—C12 | −177.8 (2) |
Cg1 and Cg2 are the centroids of the N1- and N2-rings, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
C4—H4···N2 | 0.95 | 2.50 | 2.813 (3) | 99 |
C7—H7···N1 | 0.95 | 2.46 | 2.789 (3) | 100 |
C11—H11B···N1i | 0.98 | 2.58 | 3.503 (3) | 158 |
C12—H12B···N2ii | 0.98 | 2.62 | 3.513 (3) | 151 |
C1—H1···Cg2iii | 0.95 | 2.68 | 3.515 (3) | 146 |
C12—H12A···Cg1iv | 0.98 | 2.72 | 3.439 (3) | 134 |
Symmetry codes: (i) x, y, z+1; (ii) x, y, z−1; (iii) −x, y−1/2, −z; (iv) −x+1, y+1/2, −z. |
Cg1 and Cg2 are the centroids of the N1- and N2-rings, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
C11—H11B···N1i | 0.98 | 2.58 | 3.503 (3) | 157.8 |
C12—H12B···N2ii | 0.98 | 2.62 | 3.513 (3) | 150.8 |
C1—H1···Cg2iii | 0.95 | 2.68 | 3.515 (3) | 146 |
C12—H12A···Cg1iv | 0.98 | 2.72 | 3.439 (3) | 134 |
Symmetry codes: (i) x, y, z+1; (ii) x, y, z−1; (iii) −x, y−1/2, −z; (iv) −x+1, y+1/2, −z. |
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