research communications
a,j]anthracene 1,1,2,2-tetrachloroethane monosolvate
of 1,13,14-triazadibenz[aChemical Resources Laboratory, Tokyo Institute of Technology, 4259 nagatsuta, Midori-ku, Yokohama 226-8503, Japan
*Correspondence e-mail: tkoizumi@res.titech.ac.jp
The 19H11N3·C2H2Cl4, consists of one half-molecule of 1,13,14-triazadibenz[a,j]anthracene (dibenzo[c,h]-1.9,10-anthyridine, dbanth) and one half of 1,1,2,2-tetrachloroethane (TCE), both of which are located on a crystallographic twofold rotation axis. The dihedral angle between the planes of the terminal benzene rings in dbanth is 3.59 (7)° owing to the steric repulsion between the H atoms in the two benzo groups and the H atom in the central pyridine ring of the anthridine skeleton. In the crystal, π–π interactions between pyridine rings [centroid–centroid distances = 3.568 (2) and 3.594 (2) Å] link the dbanth molecules to form a one-dimensional columnar structure along the c axis. The dbanth and TCE molecules are connected through weak bifurcated C—H⋯(N,N) hydrogen bonds.
of the title compound, CKeywords: crystal structure; 1,9,10-anthyridine; hydrogen bonding; π–π stacking.
1. Chemical context
1,9,10-Anthyridine has an anthracene skeleton with three imine N atoms that are situated at the same edge of the molecule. Since an imine unit in an aromatic compound such as pyridine can act as a hydrogen-bond acceptor, 1,9,10-anthyridine can form a triply hydrogen-bonded structure with a corresponding H-atom donor, such as 2,6-diaminopyridinium and 2,6-bis(hydroxymethyl)phenol (Murray & Zimmerman, 1992; Xu et al., 2006; Djurdjevic et al., 2007; Blight et al., 2009). Formation of multiple hydrogen bonds often corresponds to a large association constant (Ka = ca 104–1010); therefore, 1,9,10-anthyridine derivatives are promising components for supramolecular compounds. However, there have been few reports on the crystal structures of 1,9,10-anthyridine derivatives. The and intermolecular interactions of chlorobenzene-solvated 2,3,7,8-tetraphenyl-1,9,10-anthyridine have been reported (Madhavi et al., 1997). In addition, 1,13,14-triazadibenz[a,j]anthracene (dbanth) has been synthesized and its has been reported (Djurdjevic et al., 2007; Blight et al., 2009). In that case, the crystals contained no solvent molecules. In other instances, several transition-metal complexes bearing dbanth as a ligand have been reported (Wang et al., 2012; Huang et al., 2013; Hirakawa & Koizumi, 2014). In this paper, we report the of dbanth 1,1,2,2-tetrachloroethane (TCE) monosolvate, (I). The H atoms in the TCE molecule form C—H⋯N hydrogen bonds with three dbanth N atoms (Table 1).
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2. Structural commentary
The molecular structure of the title compound is depicted in Fig. 1. The dbanth and TCE molecules have twofold rotation symmetry. Although the structure of dbanth is almost planar, the planes of the terminal benzene rings are slightly twisted with respect to each other, with a dihedral angle of 3.59 (7)°. The distortion of the compound is considered to be due to the steric repulsion between atoms H5, H5* and H6. Atom H7 in the solvated TCE molecule forms a bifurcated hydrogen bond with the two N atoms (N1 and N2) of the dbanth molecule (Table 1). When dbanth was recrystallized from CHCl3, solvation of CHCl3 did not occur. This result indicates that formation of C—H⋯N hydrogen bonds stabilizes the 1:1 complex of dbanth and TCE.
3. Supramolecular features
In the crystal, the dbanth molecule interacts with the neighbouring dbanth molecule through π–π stacking interactions, with an average interplanar distance of 3.36 Å; the centroid–centroid distances between pyridine rings containing atom N1 and between pyridine rings containing atom N2 are 3.568 (2) and 3.594 (2) Å, respectively (Fig. 2). The dbanth molecules form a one-dimensional columnar structure via successive π–π stacking interactions (Fig. 3). A twofold rotation axis passes through atoms N2, C9 and H6 of the central pyridine ring, so that all of the dbanth molecules are arranged parallel to one another in the C2/c. In the crystal of nonsolvated dbanth (space group P21/c; Djurdjevic et al., 2007), dbanth molecules are also stacked in a column, but the molecules in the neighbouring columns are inclined to each other by 41.8 (2)°.
4. Synthesis and crystallization
1,13,14-Triazadibenz[a,j]anthracene (dbanth) was synthesized via the reaction of 2,6-diamino-3,5-diiodopyridine with two equivalents of 2-formylbenzeneboronic acid using Pd(PPh3)4 as a catalyst according to a literature method (Djurdjevic et al., 2007). Single crystals suitable for X-ray diffraction were obtained from a TCE solution by slow evaporation.
5. Refinement
Crystal data, data collection, and . All H atoms were fixed geometry (C—H = 0.93 or 0.98 Å) and refined using a riding model, with Uiso(H) values set at 1.2Ueq of the parent atom.
details are summarized in Table 2Supporting information
10.1107/S2056989015009263/is5393sup1.cif
contains datablocks General, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S2056989015009263/is5393Isup2.hkl
Supporting information file. DOI: 10.1107/S2056989015009263/is5393Isup3.cml
1,9,10-Anthyridine has an anthracene skeleton with three imine N atoms that are situated at the same edge of the molecule. Since an imine unit in an aromatic compound such as pyridine can act as a hydrogen-bond acceptor, 1,9,10-Anthyridine can form a triply hydrogen-bonded structure with a corresponding H-atom donor, such as 2,6-diaminopyridinium and 2,6-bis(hydroxymethyl)phenol (Murray & Zimmerman, 1992; Xu et al., 2006; Djurdjevic et al., 2007; Blight et al., 2009). Formation of multiple hydrogen bonds often corresponds to a large association constant (ca Ka = 104–1010); therefore, 1,9,10-anthyridine derivatives are promising components for supramolecular compounds. However, there have been few reports on the crystal structures of 1,9,10-anthyridine derivatives. The
and intermolecular interactions of chlorobenzene-solvated 2,3,7,8-tetraphenyl-1,9,10-anthyridine have been reported (Madhavi et al., 1997). In addition, 1,13,14-triazadibenz[a,j]anthracene (dbanth) has been synthesized and its has been reported (Djurdjevic et al., 2007; Blight et al., 2009). In that case, the crystals contained no solvent molecules. In other instances, several transition-metal complexes bearing dbanth as a ligand have been reported (Wang et al., 2012; Huang et al., 2013; Hirakawa & Koizumi, 2014). In this paper, we report the of dbanth 1,1,2,2-tetrachloroethane (TCE) monosolvate, (I). The H atoms in the TCE molecule form C—H···N hydrogen bonds with three dbanth N atoms (Table 1).The molecular structure of the titled compound is depicted in Fig. 1. The dbanth and TCE molecules have twofold rotation symmetry. Although the structure of dbanth is almost planar, the planes of the two terminal benzene rings are slightly twisted with respect to each other, with a dihedral angle of 3.59 (7)°. The distortion of the compound is considered to be due to the steric repulsion between atoms H5, H5* and H6. Atom H7 in the solvated TCE molecule forms a bifurcated hydrogen bond with the two N atoms (N1 and N2) of the dbanth molecule (Table 1). When dbanth was recrystallized from CHCl3, solvation of CHCl3 did not occur. This result indicates that formation of C—H···N hydrogen bonds stabilizes the 1:1 complex of dbanth and TCE.
In the crystal, the dbanth molecule interacts with the neighbouring dbanth molecule through π–π stacking interactions, with an average interplanar distance of 3.36 Å; the centroid–centroid distances between pyridine rings containing atom N1 and between pyridine rings containing atom N2 are 3.568 (2) and 3.594 (2) Å, respectively (Fig. 2). The dbanth molecules form a one-dimensional columnar structure via successive π–π stacking interactions (Fig. 3). A twofold rotation axis passes through atoms N2, C9 and H6 of the central pyridine ring, so that all of the dbanth molecules are arranged parallel to one another in the C2/c. In the crystal of nonsolvated dbanth (space group P21/c; Djurdjevic et al., 2007), dbanth molecules are also stacked in a column, but the molecules in the neighbouring columns are inclined to each other by 41.8 (2)°.
1,13,14-Triazadibenz[a,j]anthracene (dbanth) was synthesized via the reaction of 2,6-diamino-3,5-diiodopyridine with two equivalents of 2-formylbenzeneboronic acid using Pd(PPh3)4 as a catalyst according to a literature method (Djurdjevic et al., 2007). Single crystals suitable for X-ray diffraction were obtained from a TCE solution by slow evaporation.
Data collection: APEX2 (Bruker, 2006); cell
SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: CrystalStructure (Rigaku, 2010); software used to prepare material for publication: CrystalStructure (Rigaku, 2010).Fig. 1. The two components of the title compound, (I), with displacement ellipsoids drawn at the 50% probability level. C—H···N hydrogen bonds are shown as dashed lines. [Symmetry code: (*) -x+1, y, -z+3/2.] | |
Fig. 2. A packing diagram of the title compound, showing π–π interactions (dotted lines). | |
Fig. 3. A crystal packing of the title compound, viewed down the c axis. Dashed lines indicate C—H···N hydrogen bonds. |
C19H11N3·C2H2Cl4 | F(000) = 912.00 |
Mr = 449.14 | Dx = 1.577 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 94 reflections |
a = 20.072 (7) Å | θ = 5.4–26.8° |
b = 14.190 (5) Å | µ = 0.64 mm−1 |
c = 7.079 (3) Å | T = 90 K |
β = 110.255 (4)° | Needle, colorless |
V = 1891.5 (11) Å3 | 0.79 × 0.40 × 0.10 mm |
Z = 4 |
Bruker APEXII CCD area-detector diffractometer | 1606 reflections with F2 > 2σ(F2) |
ω scans | Rint = 0.038 |
Absorption correction: multi-scan (SADABS; Bruker, 1996) | θmax = 25.0° |
Tmin = 0.511, Tmax = 0.938 | h = −23→19 |
4336 measured reflections | k = −13→16 |
1670 independent reflections | l = −7→8 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.030 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.081 | H-atom parameters constrained |
S = 1.06 | w = 1/[σ2(Fo2) + (0.0378P)2 + 2.3451P] where P = (Fo2 + 2Fc2)/3 |
1670 reflections | (Δ/σ)max = 0.001 |
128 parameters | Δρmax = 0.50 e Å−3 |
0 restraints | Δρmin = −0.27 e Å−3 |
Primary atom site location: structure-invariant direct methods |
C19H11N3·C2H2Cl4 | V = 1891.5 (11) Å3 |
Mr = 449.14 | Z = 4 |
Monoclinic, C2/c | Mo Kα radiation |
a = 20.072 (7) Å | µ = 0.64 mm−1 |
b = 14.190 (5) Å | T = 90 K |
c = 7.079 (3) Å | 0.79 × 0.40 × 0.10 mm |
β = 110.255 (4)° |
Bruker APEXII CCD area-detector diffractometer | 1670 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 1996) | 1606 reflections with F2 > 2σ(F2) |
Tmin = 0.511, Tmax = 0.938 | Rint = 0.038 |
4336 measured reflections |
R[F2 > 2σ(F2)] = 0.030 | 0 restraints |
wR(F2) = 0.081 | H-atom parameters constrained |
S = 1.06 | Δρmax = 0.50 e Å−3 |
1670 reflections | Δρmin = −0.27 e Å−3 |
128 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 was performed using all reflections. The weighted R-factor (wR) and goodness of fit (S) are based on F2. R-factor (gt) are based on F. The threshold expression of F2 > 2.0 σ(F2) is used only for calculating R-factor (gt). |
x | y | z | Uiso*/Ueq | ||
Cl1 | 0.41196 (2) | 0.93210 (3) | 0.70600 (6) | 0.02318 (16) | |
Cl2 | 0.46383 (2) | 0.83298 (3) | 0.42650 (6) | 0.02069 (15) | |
N1 | 0.38456 (7) | 0.62220 (9) | 0.53448 (19) | 0.0148 (3) | |
N2 | 0.5000 | 0.61449 (12) | 0.7500 | 0.0129 (4) | |
C1 | 0.32689 (8) | 0.57917 (11) | 0.4258 (2) | 0.0158 (3) | |
H1 | 0.2883 | 0.6168 | 0.3558 | 0.019* | |
C2 | 0.31719 (8) | 0.47862 (11) | 0.4035 (2) | 0.0144 (3) | |
C3 | 0.25243 (8) | 0.43881 (12) | 0.2803 (2) | 0.0179 (3) | |
H2 | 0.2145 | 0.4778 | 0.2120 | 0.022* | |
C4 | 0.24495 (8) | 0.34260 (12) | 0.2603 (3) | 0.0205 (4) | |
H3 | 0.2021 | 0.3164 | 0.1793 | 0.025* | |
C5 | 0.30269 (8) | 0.28419 (12) | 0.3637 (2) | 0.0193 (4) | |
H4 | 0.2978 | 0.2191 | 0.3497 | 0.023* | |
C6 | 0.36626 (8) | 0.32177 (11) | 0.4851 (2) | 0.0152 (3) | |
H5 | 0.4039 | 0.2820 | 0.5522 | 0.018* | |
C7 | 0.37471 (8) | 0.42004 (11) | 0.5082 (2) | 0.0122 (3) | |
C8 | 0.43950 (7) | 0.46557 (10) | 0.6339 (2) | 0.0112 (3) | |
C9 | 0.5000 | 0.41722 (14) | 0.7500 | 0.0110 (4) | |
H6 | 0.5000 | 0.3517 | 0.7500 | 0.013* | |
C10 | 0.44225 (8) | 0.56624 (10) | 0.6410 (2) | 0.0115 (3) | |
C11 | 0.46206 (8) | 0.83406 (10) | 0.6758 (2) | 0.0150 (3) | |
H7 | 0.4386 | 0.7764 | 0.6963 | 0.018* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0185 (2) | 0.0215 (2) | 0.0267 (3) | 0.00797 (15) | 0.00433 (19) | −0.00421 (15) |
Cl2 | 0.0227 (2) | 0.0234 (3) | 0.0136 (2) | 0.00366 (15) | 0.00322 (19) | −0.00042 (14) |
N1 | 0.0132 (7) | 0.0162 (7) | 0.0140 (7) | 0.0038 (5) | 0.0035 (5) | 0.0018 (5) |
N2 | 0.0126 (9) | 0.0133 (9) | 0.0129 (9) | 0.000 | 0.0043 (7) | 0.000 |
C1 | 0.0119 (8) | 0.0202 (8) | 0.0135 (8) | 0.0070 (6) | 0.0023 (6) | 0.0039 (6) |
C2 | 0.0102 (7) | 0.0211 (8) | 0.0118 (7) | 0.0020 (6) | 0.0039 (6) | 0.0016 (6) |
C3 | 0.0079 (7) | 0.0284 (9) | 0.0154 (8) | 0.0033 (6) | 0.0014 (6) | 0.0029 (6) |
C4 | 0.0089 (7) | 0.0298 (9) | 0.0186 (9) | −0.0055 (6) | −0.0005 (7) | −0.0003 (7) |
C5 | 0.0157 (8) | 0.0187 (8) | 0.0204 (8) | −0.0042 (6) | 0.0026 (7) | 0.0004 (6) |
C6 | 0.0103 (7) | 0.0176 (8) | 0.0146 (8) | −0.0002 (6) | 0.0006 (6) | 0.0020 (6) |
C7 | 0.0091 (7) | 0.0174 (8) | 0.0103 (7) | −0.0004 (6) | 0.0036 (6) | 0.0009 (5) |
C8 | 0.0092 (7) | 0.0152 (8) | 0.0097 (7) | −0.0001 (6) | 0.0039 (6) | −0.0002 (5) |
C9 | 0.0108 (10) | 0.0104 (10) | 0.0114 (10) | 0.000 | 0.0036 (9) | 0.000 |
C10 | 0.0111 (7) | 0.0136 (7) | 0.0104 (8) | 0.0011 (5) | 0.0045 (6) | 0.0010 (5) |
C11 | 0.0158 (8) | 0.0130 (8) | 0.0154 (8) | 0.0017 (6) | 0.0046 (7) | −0.0008 (6) |
Cl1—C11 | 1.7722 (15) | C4—H3 | 0.9300 |
Cl2—C11 | 1.7778 (17) | C5—C6 | 1.376 (2) |
N1—C1 | 1.299 (2) | C5—H4 | 0.9300 |
N1—C10 | 1.3913 (19) | C6—C7 | 1.407 (2) |
N2—C10 | 1.3373 (18) | C6—H5 | 0.9300 |
N2—C10i | 1.3373 (18) | C7—C8 | 1.449 (2) |
C1—C2 | 1.441 (2) | C8—C9 | 1.3891 (18) |
C1—H1 | 0.9300 | C8—C10 | 1.430 (2) |
C2—C7 | 1.407 (2) | C9—C8i | 1.3891 (18) |
C2—C3 | 1.409 (2) | C9—H6 | 0.9300 |
C3—C4 | 1.375 (2) | C11—C11i | 1.522 (3) |
C3—H2 | 0.9300 | C11—H7 | 0.9800 |
C4—C5 | 1.406 (2) | ||
C1—N1—C10 | 117.16 (13) | C7—C6—H5 | 119.8 |
C10—N2—C10i | 118.40 (18) | C6—C7—C2 | 118.69 (14) |
N1—C1—C2 | 126.09 (14) | C6—C7—C8 | 124.04 (14) |
N1—C1—H1 | 117.0 | C2—C7—C8 | 117.28 (14) |
C2—C1—H1 | 117.0 | C9—C8—C10 | 117.23 (13) |
C7—C2—C3 | 120.14 (15) | C9—C8—C7 | 123.92 (14) |
C7—C2—C1 | 118.16 (14) | C10—C8—C7 | 118.86 (13) |
C3—C2—C1 | 121.70 (14) | C8i—C9—C8 | 120.80 (19) |
C4—C3—C2 | 120.41 (15) | C8i—C9—H6 | 119.6 |
C4—C3—H2 | 119.8 | C8—C9—H6 | 119.6 |
C2—C3—H2 | 119.8 | N2—C10—N1 | 114.40 (14) |
C3—C4—C5 | 119.38 (15) | N2—C10—C8 | 123.16 (14) |
C3—C4—H3 | 120.3 | N1—C10—C8 | 122.44 (13) |
C5—C4—H3 | 120.3 | C11i—C11—Cl1 | 113.02 (9) |
C6—C5—C4 | 121.04 (15) | C11i—C11—Cl2 | 109.00 (14) |
C6—C5—H4 | 119.5 | Cl1—C11—Cl2 | 109.48 (8) |
C4—C5—H4 | 119.5 | C11i—C11—H7 | 108.4 |
C5—C6—C7 | 120.35 (14) | Cl1—C11—H7 | 108.4 |
C5—C6—H5 | 119.8 | Cl2—C11—H7 | 108.4 |
C10—N1—C1—C2 | −0.6 (2) | C6—C7—C8—C9 | −1.8 (2) |
N1—C1—C2—C7 | 0.2 (2) | C2—C7—C8—C9 | 178.34 (11) |
N1—C1—C2—C3 | −179.50 (14) | C6—C7—C8—C10 | 178.32 (13) |
C7—C2—C3—C4 | −0.3 (2) | C2—C7—C8—C10 | −1.6 (2) |
C1—C2—C3—C4 | 179.35 (15) | C10—C8—C9—C8i | −0.54 (9) |
C2—C3—C4—C5 | −0.2 (2) | C7—C8—C9—C8i | 179.54 (15) |
C3—C4—C5—C6 | 0.4 (3) | C10i—N2—C10—N1 | 179.30 (14) |
C4—C5—C6—C7 | 0.0 (2) | C10i—N2—C10—C8 | −0.61 (10) |
C5—C6—C7—C2 | −0.6 (2) | C1—N1—C10—N2 | 180.00 (12) |
C5—C6—C7—C8 | 179.54 (14) | C1—N1—C10—C8 | −0.1 (2) |
C3—C2—C7—C6 | 0.7 (2) | C9—C8—C10—N2 | 1.18 (19) |
C1—C2—C7—C6 | −178.97 (14) | C7—C8—C10—N2 | −178.90 (11) |
C3—C2—C7—C8 | −179.37 (13) | C9—C8—C10—N1 | −178.71 (11) |
C1—C2—C7—C8 | 0.9 (2) | C7—C8—C10—N1 | 1.2 (2) |
Symmetry code: (i) −x+1, y, −z+3/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H7···C11 | 0.98 | 2.53 | 3.372 (3) | 144 |
N2—H7···C11 | 0.98 | 2.57 | 3.206 (3) | 122 |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H7···C11 | 0.98 | 2.53 | 3.372 (3) | 144 |
N2—H7···C11 | 0.98 | 2.57 | 3.206 (3) | 122 |
Experimental details
Crystal data | |
Chemical formula | C19H11N3·C2H2Cl4 |
Mr | 449.14 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 90 |
a, b, c (Å) | 20.072 (7), 14.190 (5), 7.079 (3) |
β (°) | 110.255 (4) |
V (Å3) | 1891.5 (11) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.64 |
Crystal size (mm) | 0.79 × 0.40 × 0.10 |
Data collection | |
Diffractometer | Bruker APEXII CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 1996) |
Tmin, Tmax | 0.511, 0.938 |
No. of measured, independent and observed [F2 > 2σ(F2)] reflections | 4336, 1670, 1606 |
Rint | 0.038 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.030, 0.081, 1.06 |
No. of reflections | 1670 |
No. of parameters | 128 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.50, −0.27 |
Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2004), SHELXT (Sheldrick, 2015a), SHELXL2014 (Sheldrick, 2015b), CrystalStructure (Rigaku, 2010).
Acknowledgements
This work was supported by a Grant-in-Aid for Scientific Research on Innovative Areas of New Polymeric Materials Based on Element-Blocks (No. 2401) (24102013) from the Ministry of Education, Culture, Sports, Science, and Technology, Japan.
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