Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536803017598/tk6125sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536803017598/tk6125Isup2.hkl |
CCDC reference: 222867
A solution of terephthalaldehyde and 2-aminopyridine in toluene was heated under reflux with stirring in a Dean–Stark apparatus. After 12 h, the solvent was removed under vacuum, and the remains, without further purification, were reduced in the absolute methanol by sodium borohydride, as described in the literature (Ashton et al., 1997). Colorless crystals were obtained by recrystallization of the material from methanol. Yield: 87%, m.p.: 465–467 K. Analysis calculated for C18H18N4: C 74.46, H 6.25, N 19.29%; found: C 74.08, H 6.58, N 19.34%. 1H NMR (300 MHz, CDCl3): δ 4.50 (s, 4H), 6.37 (d, 2H), 6.59 (m, 2H), 7.33 (s, 4H), 7.40 (m, 2H), 8.10 (m, 2H).
H atoms on C atoms were included in the riding-model approximation so that pheny C—H = 0.95 Å or methylene C—H = 0.97 Å and given displacement parameters equal to 1.2Ueq of the atom to which they were bonded. The H atom on the N atom was allowed to refine freely.
Data collection: SMART (Bruker, 1998); cell refinement: SMART; data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1997); software used to prepare material for publication: SHELXTL.
Fig. 1. View of the title compound, with displacement ellipsoids drawn at the 30% probability level. |
C18H18N4 | F(000) = 616 |
Mr = 290.36 | Dx = 1.272 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 548 reflections |
a = 18.547 (11) Å | θ = 4.6–25.4° |
b = 5.539 (3) Å | µ = 0.08 mm−1 |
c = 15.303 (9) Å | T = 293 K |
β = 105.328 (8)° | Block, colorless |
V = 1516.3 (15) Å3 | 0.42 × 0.22 × 0.20 mm |
Z = 4 |
Bruker SMART CCD area-detector diffractometer | 1534 independent reflections |
Radiation source: fine-focus sealed tube | 1093 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.023 |
ϕ and ω scans | θmax = 26.4°, θmin = 3.1° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −22→17 |
Tmin = 0.797, Tmax = 0.990 | k = −6→5 |
3292 measured reflections | l = −18→19 |
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) = 0.111 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | w = 1/[σ2(Fo2) + (0.0526P)2 + 0.3246P] where P = (Fo2 + 2Fc2)/3 |
1534 reflections | (Δ/σ)max < 0.001 |
104 parameters | Δρmax = 0.13 e Å−3 |
0 restraints | Δρmin = −0.15 e Å−3 |
C18H18N4 | V = 1516.3 (15) Å3 |
Mr = 290.36 | Z = 4 |
Monoclinic, C2/c | Mo Kα radiation |
a = 18.547 (11) Å | µ = 0.08 mm−1 |
b = 5.539 (3) Å | T = 293 K |
c = 15.303 (9) Å | 0.42 × 0.22 × 0.20 mm |
β = 105.328 (8)° |
Bruker SMART CCD area-detector diffractometer | 1534 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 1093 reflections with I > 2σ(I) |
Tmin = 0.797, Tmax = 0.990 | Rint = 0.023 |
3292 measured reflections |
R[F2 > 2σ(F2)] = 0.044 | 0 restraints |
wR(F2) = 0.111 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | Δρmax = 0.13 e Å−3 |
1534 reflections | Δρmin = −0.15 e Å−3 |
104 parameters |
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 | 0.28908 (10) | 0.5376 (3) | 0.69349 (11) | 0.0534 (5) | |
H1 | 0.2546 | 0.4138 | 0.6900 | 0.064* | |
C2 | 0.34709 (11) | 0.5526 (4) | 0.76984 (12) | 0.0603 (5) | |
H2 | 0.3520 | 0.4426 | 0.8170 | 0.072* | |
C3 | 0.39798 (11) | 0.7361 (4) | 0.77459 (12) | 0.0583 (5) | |
H3 | 0.4383 | 0.7512 | 0.8255 | 0.070* | |
C4 | 0.38954 (9) | 0.8959 (3) | 0.70480 (11) | 0.0496 (4) | |
H4 | 0.4238 | 1.0202 | 0.7074 | 0.060* | |
C5 | 0.32818 (8) | 0.8686 (3) | 0.62903 (10) | 0.0387 (4) | |
C6 | 0.36767 (8) | 1.1973 (3) | 0.54305 (11) | 0.0459 (4) | |
H6A | 0.3834 | 1.2968 | 0.5969 | 0.055* | |
H6B | 0.3432 | 1.3021 | 0.4933 | 0.055* | |
C7 | 0.43661 (8) | 1.0906 (3) | 0.52261 (9) | 0.0374 (4) | |
C8 | 0.50399 (9) | 1.2093 (3) | 0.54765 (12) | 0.0472 (4) | |
H8 | 0.5076 | 1.3522 | 0.5804 | 0.057* | |
C9 | 0.43337 (9) | 0.8784 (3) | 0.47466 (11) | 0.0491 (4) | |
H9 | 0.3886 | 0.7934 | 0.4571 | 0.059* | |
N1 | 0.31354 (7) | 1.0241 (3) | 0.55711 (9) | 0.0450 (4) | |
H1A | 0.2818 (10) | 0.960 (3) | 0.5087 (13) | 0.060 (5)* | |
N2 | 0.27875 (7) | 0.6894 (2) | 0.62341 (9) | 0.0459 (4) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0550 (11) | 0.0531 (11) | 0.0561 (10) | −0.0038 (9) | 0.0216 (8) | 0.0031 (9) |
C2 | 0.0685 (12) | 0.0655 (12) | 0.0481 (10) | 0.0084 (11) | 0.0175 (9) | 0.0139 (9) |
C3 | 0.0543 (11) | 0.0730 (13) | 0.0417 (10) | 0.0089 (10) | 0.0024 (8) | 0.0033 (9) |
C4 | 0.0428 (9) | 0.0566 (10) | 0.0466 (9) | −0.0043 (8) | 0.0066 (7) | −0.0007 (8) |
C5 | 0.0323 (8) | 0.0458 (9) | 0.0404 (8) | 0.0048 (7) | 0.0138 (6) | −0.0019 (7) |
C6 | 0.0420 (9) | 0.0444 (9) | 0.0527 (9) | 0.0041 (8) | 0.0148 (7) | 0.0041 (8) |
C7 | 0.0389 (8) | 0.0368 (8) | 0.0363 (7) | 0.0004 (7) | 0.0096 (6) | 0.0030 (7) |
C8 | 0.0469 (10) | 0.0404 (9) | 0.0554 (10) | −0.0071 (8) | 0.0157 (8) | −0.0129 (8) |
C9 | 0.0373 (9) | 0.0521 (10) | 0.0577 (10) | −0.0103 (8) | 0.0123 (7) | −0.0114 (8) |
N1 | 0.0345 (7) | 0.0560 (9) | 0.0431 (8) | −0.0007 (7) | 0.0076 (6) | 0.0040 (7) |
N2 | 0.0397 (7) | 0.0542 (9) | 0.0454 (7) | −0.0034 (7) | 0.0139 (6) | 0.0003 (7) |
C1—N2 | 1.336 (2) | C6—N1 | 1.445 (2) |
C1—C2 | 1.366 (2) | C6—C7 | 1.514 (2) |
C1—H1 | 0.9300 | C6—H6A | 0.9700 |
C2—C3 | 1.376 (3) | C6—H6B | 0.9700 |
C2—H2 | 0.9300 | C7—C8 | 1.374 (2) |
C3—C4 | 1.364 (2) | C7—C9 | 1.378 (2) |
C3—H3 | 0.9300 | C8—C9i | 1.383 (2) |
C4—C5 | 1.402 (2) | C8—H8 | 0.9300 |
C4—H4 | 0.9300 | C9—C8i | 1.383 (2) |
C5—N2 | 1.339 (2) | C9—H9 | 0.9300 |
C5—N1 | 1.367 (2) | N1—H1A | 0.889 (19) |
N2—C1—C2 | 124.18 (17) | C7—C6—H6A | 108.4 |
N2—C1—H1 | 117.9 | N1—C6—H6B | 108.4 |
C2—C1—H1 | 117.9 | C7—C6—H6B | 108.4 |
C1—C2—C3 | 117.67 (17) | H6A—C6—H6B | 107.5 |
C1—C2—H2 | 121.2 | C8—C7—C9 | 117.72 (14) |
C3—C2—H2 | 121.2 | C8—C7—C6 | 120.72 (14) |
C4—C3—C2 | 120.20 (18) | C9—C7—C6 | 121.49 (14) |
C4—C3—H3 | 119.9 | C7—C8—C9i | 121.64 (15) |
C2—C3—H3 | 119.9 | C7—C8—H8 | 119.2 |
C3—C4—C5 | 118.55 (17) | C9i—C8—H8 | 119.2 |
C3—C4—H4 | 120.7 | C7—C9—C8i | 120.64 (15) |
C5—C4—H4 | 120.7 | C7—C9—H9 | 119.7 |
N2—C5—N1 | 115.38 (14) | C8i—C9—H9 | 119.7 |
N2—C5—C4 | 121.70 (15) | C5—N1—C6 | 122.69 (14) |
N1—C5—C4 | 122.91 (15) | C5—N1—H1A | 111.5 (12) |
N1—C6—C7 | 115.43 (13) | C6—N1—H1A | 118.2 (11) |
N1—C6—H6A | 108.4 | C1—N2—C5 | 117.70 (15) |
N2—C1—C2—C3 | 0.0 (3) | C8—C7—C9—C8i | −0.5 (3) |
C1—C2—C3—C4 | 0.2 (3) | C6—C7—C9—C8i | 176.42 (15) |
C2—C3—C4—C5 | 0.1 (3) | N2—C5—N1—C6 | −167.44 (13) |
C3—C4—C5—N2 | −0.8 (2) | C4—C5—N1—C6 | 14.0 (2) |
C3—C4—C5—N1 | 177.75 (15) | C7—C6—N1—C5 | 65.9 (2) |
N1—C6—C7—C8 | −150.12 (15) | C2—C1—N2—C5 | −0.6 (2) |
N1—C6—C7—C9 | 33.1 (2) | N1—C5—N2—C1 | −177.65 (13) |
C9—C7—C8—C9i | 0.5 (3) | C4—C5—N2—C1 | 1.0 (2) |
C6—C7—C8—C9i | −176.44 (15) |
Symmetry code: (i) −x+1, −y+2, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C18H18N4 |
Mr | 290.36 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 293 |
a, b, c (Å) | 18.547 (11), 5.539 (3), 15.303 (9) |
β (°) | 105.328 (8) |
V (Å3) | 1516.3 (15) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.42 × 0.22 × 0.20 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.797, 0.990 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3292, 1534, 1093 |
Rint | 0.023 |
(sin θ/λ)max (Å−1) | 0.626 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.044, 0.111, 1.02 |
No. of reflections | 1534 |
No. of parameters | 104 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.13, −0.15 |
Computer programs: SMART (Bruker, 1998), SMART, SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 1997), SHELXTL.
Studies of the molecular self-assembly of flexible N-heterocyclic ligands with metal ions have attracted much attention. This is mainly attributed to their applications in many fields as well as the versatile structures and properties their molecular assemblies display (Clayden & Pink, 1998; Hong et al., 2000; Kang et al., 2002). There is growing interest in finding alternative approaches for building new inexpensive and easy-to-prepare supramolecular systems. According to the above, we designed and synthesized a new flexible, potentially tetradentate, ligand, viz. 1,4-bis(pyridine-2-aminomethyl)benzene, (I), which may provide a new and versatile ligand for metal ions.
The molecule of (I) (Fig. 1) is disposed about a centre of inversion with the two parallel pyridyl terminal groups are in a trans arrangment. The dihedral angle between the pyridyl ring and the central phenyl group is 87°. The crystal structure is stabilized by the presence of intermolecular hydrogen-bonding interactions between pyridyl-N and the amino-H atom on a symmetry-related moleculae so that N1—H···N2i is 2.198 (19) Å, N1···N2i is 3.076 (3) Å and the angle subtended at H is 168.8 (17)° [symmetry code: (i) 1/2 − x, 3/2 − y, 1 − z]. These interactions give rise to a chain structure.