Acta Cryst. (2009). E65, o285 [ doi:10.1107/S1600536809000658 ]
The title compound, C20H18N4, is a flexible 3,3'-bipyridyl-type ligand with a long spacer group between the two pyridyl functions. The molecule crystallizes around an inversion center, with one half-molecule in the asymmetric unit and a dihedral angle of 71.85 (8)° between the pyridine ring and the central benzene ring.
The title compound was synthesized and purified according to the method described by by Haga et al. (1985), by the condensation reaction of pyridine-3-carboxaldehyde and 1,4-benzenedimethanamine (yield 83%). Colorless block single crystals (m.p. 397–397.2 K) suitable for X-ray analysis were obtained by slow evaporation of a methanol solution at room temperature. Analysis calclated for C20H18N4: C 76.41, H 5.77, N 17.82%; found: C 76.53, H 5.74, N 17.75%. IR (KBr pellet, cm-1): 3436 (b), 3060 (m), 3048 (m), 2942 (m), 2903 (m), 2849 (m), 1640 (s), 1586 (s), 1565 (s), 1469 (s), 1434 (s), 1359 (m), 1324 (m), 1150 (w), 1015 (m), 990 (m), 848 (s), 777 (s), 739 (m), 617 (w), 571 (m), 506 (m), 403 (w).
H atoms were assigned to calculated positions, with C—H = 0.97 (methylene) and 0.93Å (aromatic), and refined using a riding model, with Uiso(H) = 1.2 Ueq(C).
Data collection: SMART (Bruker, 2000); cell refinement: SMART (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).
![[Figure 1]](./zl2166fig1thm.gif)
| Fig. 1. The molecular structure of the title compound (thermal ellipsoids are shown at 30% probability levels). |
| C20H18N4 | F(000) = 332 |
| Mr = 314.38 | Dx = 1.239 Mg m−3 |
| Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
| Hall symbol: -P 2ybc | Cell parameters from 2797 reflections |
| a = 6.0990 (11) Å | θ = 2.6–27.2° |
| b = 14.589 (3) Å | µ = 0.08 mm−1 |
| c = 9.9481 (18) Å | T = 291 K |
| β = 107.851 (3)° | Block, colorless |
| V = 842.5 (3) Å3 | 0.24 × 0.22 × 0.20 mm |
| Z = 2 |
| Bruker SMART APEX CCD diffractometer | 1661 independent reflections |
| Radiation source: sealed tube | 1085 reflections with I > 2σ(I) |
| graphite | Rint = 0.045 |
| φ and ω scans | θmax = 26.0°, θmin = 2.6° |
| Absorption correction: multi-scan (SADABS; Bruker, 2000) | h = −7→7 |
| Tmin = 0.98, Tmax = 0.98 | k = −17→17 |
| 6535 measured reflections | l = −11→12 |
| 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)] = 0.048 | Hydrogen site location: inferred from neighbouring sites |
| wR(F2) = 0.101 | H-atom parameters constrained |
| S = 1.01 | w = 1/[σ2(Fo2) + (0.04P)2] where P = (Fo2 + 2Fc2)/3 |
| 1661 reflections | (Δ/σ)max < 0.001 |
| 109 parameters | Δρmax = 0.13 e Å−3 |
| 0 restraints | Δρmin = −0.12 e Å−3 |
| C20H18N4 | V = 842.5 (3) Å3 |
| Mr = 314.38 | Z = 2 |
| Monoclinic, P21/c | Mo Kα radiation |
| a = 6.0990 (11) Å | µ = 0.08 mm−1 |
| b = 14.589 (3) Å | T = 291 K |
| c = 9.9481 (18) Å | 0.24 × 0.22 × 0.20 mm |
| β = 107.851 (3)° |
| Bruker SMART APEX CCD diffractometer | 1661 independent reflections |
| Absorption correction: multi-scan (SADABS; Bruker, 2000) | 1085 reflections with I > 2σ(I) |
| Tmin = 0.98, Tmax = 0.98 | Rint = 0.045 |
| 6535 measured reflections | θmax = 26.0° |
| R[F2 > 2σ(F2)] = 0.048 | H-atom parameters constrained |
| wR(F2) = 0.101 | Δρmax = 0.13 e Å−3 |
| S = 1.01 | Δρmin = −0.12 e Å−3 |
| 1661 reflections | Absolute structure: ? |
| 109 parameters | Flack parameter: ? |
| 0 restraints | Rogers parameter: ? |
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. |
| x | y | z | Uiso*/Ueq | ||
| C1 | 0.0338 (3) | 0.59733 (9) | 0.90988 (16) | 0.0402 (4) | |
| C2 | 0.2284 (3) | 0.63315 (11) | 1.00966 (18) | 0.0512 (4) | |
| H2 | 0.3749 | 0.6142 | 1.0117 | 0.061* | |
| C3 | 0.2005 (3) | 0.69698 (11) | 1.1050 (2) | 0.0592 (5) | |
| H3 | 0.3278 | 0.7216 | 1.1728 | 0.071* | |
| C4 | −0.0183 (4) | 0.72359 (11) | 1.0983 (2) | 0.0627 (5) | |
| H4 | −0.0346 | 0.7673 | 1.1625 | 0.075* | |
| C5 | −0.1780 (3) | 0.62821 (11) | 0.91503 (19) | 0.0522 (4) | |
| H5 | −0.3091 | 0.6036 | 0.8506 | 0.063* | |
| C6 | 0.0482 (3) | 0.53005 (10) | 0.80278 (16) | 0.0418 (4) | |
| H6 | −0.0874 | 0.5064 | 0.7416 | 0.050* | |
| C7 | 0.2348 (3) | 0.43652 (11) | 0.68220 (17) | 0.0475 (4) | |
| H7A | 0.0771 | 0.4255 | 0.6247 | 0.057* | |
| H7B | 0.2981 | 0.3791 | 0.7264 | 0.057* | |
| C8 | 0.3738 (3) | 0.46922 (10) | 0.58876 (15) | 0.0390 (4) | |
| C9 | 0.3934 (3) | 0.56235 (10) | 0.56217 (16) | 0.0430 (4) | |
| H9 | 0.3223 | 0.6050 | 0.6044 | 0.052* | |
| C10 | 0.5155 (3) | 0.59265 (10) | 0.47492 (17) | 0.0424 (4) | |
| H10 | 0.5239 | 0.6551 | 0.4585 | 0.051* | |
| N1 | −0.2079 (3) | 0.69096 (10) | 1.00596 (19) | 0.0667 (5) | |
| N2 | 0.2369 (2) | 0.50359 (9) | 0.79117 (15) | 0.0489 (4) |
| U11 | U22 | U33 | U12 | U13 | U23 | |
| C1 | 0.0437 (9) | 0.0402 (7) | 0.0394 (9) | −0.0009 (6) | 0.0165 (7) | 0.0070 (6) |
| C2 | 0.0458 (10) | 0.0571 (10) | 0.0500 (10) | 0.0002 (8) | 0.0134 (8) | −0.0032 (8) |
| C3 | 0.0643 (12) | 0.0516 (10) | 0.0579 (12) | −0.0079 (8) | 0.0134 (9) | −0.0118 (8) |
| C4 | 0.0786 (14) | 0.0431 (9) | 0.0738 (13) | −0.0012 (9) | 0.0345 (11) | −0.0131 (9) |
| C5 | 0.0470 (9) | 0.0501 (9) | 0.0600 (11) | 0.0011 (8) | 0.0169 (8) | −0.0034 (8) |
| C6 | 0.0425 (9) | 0.0458 (8) | 0.0374 (9) | −0.0011 (6) | 0.0127 (7) | 0.0029 (6) |
| C7 | 0.0467 (9) | 0.0508 (8) | 0.0462 (9) | 0.0005 (7) | 0.0161 (7) | −0.0041 (7) |
| C8 | 0.0379 (8) | 0.0423 (7) | 0.0333 (9) | 0.0013 (6) | 0.0055 (6) | −0.0063 (6) |
| C9 | 0.0464 (9) | 0.0423 (7) | 0.0414 (9) | 0.0065 (7) | 0.0149 (7) | −0.0081 (7) |
| C10 | 0.0477 (9) | 0.0346 (7) | 0.0442 (9) | 0.0017 (6) | 0.0129 (7) | −0.0025 (6) |
| N1 | 0.0609 (10) | 0.0550 (9) | 0.0887 (13) | 0.0041 (8) | 0.0297 (9) | −0.0173 (8) |
| N2 | 0.0478 (8) | 0.0624 (9) | 0.0393 (8) | 0.0002 (6) | 0.0175 (6) | −0.0074 (6) |
| C1—C5 | 1.384 (2) | C6—H6 | 0.9300 |
| C1—C2 | 1.395 (2) | C7—N2 | 1.458 (2) |
| C1—C6 | 1.471 (2) | C7—C8 | 1.514 (2) |
| C2—C3 | 1.376 (2) | C7—H7A | 0.9700 |
| C2—H2 | 0.9300 | C7—H7B | 0.9700 |
| C3—C4 | 1.372 (3) | C8—C10i | 1.391 (2) |
| C3—H3 | 0.9300 | C8—C9 | 1.396 (2) |
| C4—N1 | 1.325 (3) | C9—C10 | 1.378 (2) |
| C4—H4 | 0.9300 | C9—H9 | 0.9300 |
| C5—N1 | 1.338 (2) | C10—C8i | 1.391 (2) |
| C5—H5 | 0.9300 | C10—H10 | 0.9300 |
| C6—N2 | 1.253 (2) | ||
| C5—C1—C2 | 116.88 (15) | N2—C7—C8 | 111.49 (13) |
| C5—C1—C6 | 120.51 (15) | N2—C7—H7A | 109.3 |
| C2—C1—C6 | 122.61 (14) | C8—C7—H7A | 109.3 |
| C3—C2—C1 | 119.09 (16) | N2—C7—H7B | 109.3 |
| C3—C2—H2 | 120.5 | C8—C7—H7B | 109.3 |
| C1—C2—H2 | 120.5 | H7A—C7—H7B | 108.0 |
| C4—C3—C2 | 118.78 (18) | C10i—C8—C9 | 117.60 (13) |
| C4—C3—H3 | 120.6 | C10i—C8—C7 | 121.10 (13) |
| C2—C3—H3 | 120.6 | C9—C8—C7 | 121.30 (12) |
| N1—C4—C3 | 124.15 (17) | C10—C9—C8 | 121.72 (13) |
| N1—C4—H4 | 117.9 | C10—C9—H9 | 119.1 |
| C3—C4—H4 | 117.9 | C8—C9—H9 | 119.1 |
| N1—C5—C1 | 124.74 (18) | C9—C10—C8i | 120.68 (13) |
| N1—C5—H5 | 117.6 | C9—C10—H10 | 119.7 |
| C1—C5—H5 | 117.6 | C8i—C10—H10 | 119.7 |
| N2—C6—C1 | 122.21 (15) | C4—N1—C5 | 116.34 (16) |
| N2—C6—H6 | 118.9 | C6—N2—C7 | 118.48 (14) |
| C1—C6—H6 | 118.9 |
| Symmetry codes: (i) −x+1, −y+1, −z+1. |
The authors thank the Center for Testing and Analysis at Yangzhou University for support.
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Cho, B. Y., Min, D. W. & Lee, S. W. (2006). Cryst. Growth Des. 6, 342–347.
Haga, M. & Koizumi, K. (1985). Inorg. Chim. Acta, 104, 47–50.
Mahmoudi, G., Morsali, A., Hunter, A. D. & Zeller, M. (2007). CrystEngComm, 9, 704–714.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.
Wang, Q., Yang, R., Zhuang, C. F., Zhang, J. Y., Kang, B. S. & Su, C. Y. (2008). Eur. J. Inorg. Chem. 10, 1702–1711.
Bipyridyl-type bidentate Schiff base ligands have been utilized intensively to assemble various coordination polymers with interesting topologies and fascinating structural diversities (Cho et al., 2006; Mahmoudi et al., 2007; Wang et al., 2008). We report here the crystal structure of the title compound.
A perspective view of the title compound, including the atomic numbering scheme, is shown in Fig. 1. The title compound crystallizes around a crystallographic center with half a molecule in the asymmetric unit. The bond lengths and angles are within normal ranges. The terminal pyridyl groups are coplanar, and they form a dihedral angle of 71.85 (8)° with the central benzene ring. The molecular structure is stabilized by an intramolecular C9—H9···N2 bond (Table 1), but no classical intermolecular interactions have been found in the crystal packing of the title compound.