One-dimensional hydrogen-bonded molecular tapes in 1,4-bis­[(4-pyridinio)­ethynyl]­benzene chloranilate

The structure of the title compound, C₂₀H₁₄N₂²⁺·C₆Cl₂O₄²⁻, contains one-dimensional hydrogen-bonded molecular tapes along the [113] direction. The molecular tapes are connected via two N—H...O hydrogen bonds in R₁²(5) patterns.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.053
• wR factor = 0.161
• Data-to-parameter ratio = 12.0

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level C:



PLAT_213  Alert C Atom  O1     has ADP max/min Ratio ...........       3.20

PLAT_213  Alert C Atom  O2     has ADP max/min Ratio ...........       3.10

PLAT_353  Alert C Long  N-H Bond (0.87A)     N(1)   -   H(1)   =       1.05 Ang.

PLAT_371  Alert C Long   C(sp2)-C(sp1) Bond  C(5)   -   C(7)   =       1.44 Ang.

PLAT_371  Alert C Long   C(sp2)-C(sp1) Bond  C(8)   -   C(9)   =       1.43 Ang.


 0 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 5 Alert Level C = Please check

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S1. Comment

We have recently shown that the simple combination of chloranilic acid and dipyridyl-type ligands can create a variety of supramolecular architectures involving infinite one-dimensional molecular tape structures (Zaman et al., 1999, 2000). In the course of our crystal engineering studies on chloranilic acid, we have obtained the title compound, (I), a 1:1 co-crystal of chloranilic acid and 1,4-bis[(4-pyridyl)ethynyl]benzene. A long rigid and conjugated bridging ligand has received much current interest for the construction of self-assembling macrocyclic architectures (Lehn, 1995; Fujita, 1999) and the development of molecular wires (Tour, 1996). However, we have found only two examples (Lin et al., 1995, 1998) of the structures containing a 1,4-bis[(4-pyridyl)ethynyl]benzene unit in the Cambridge Structural Database (Allen & Kennard, 1993). We report here the structure of (I) with the hydrogen-bonded molecular tapes.

The molecular structure of (I) is shown in Fig. 1, and both molecules are located on the inversion center. A one-dimensional molecular tape is observed in the structure of (I), as shown in Fig. 2. The molecular tape is nearly flat. The angles between the molecular planes of the chloranilate and the pyridinium ring, and of the pyridinium ring and the benzene ring are 7.3 (2) and 11.8 (4)°, respectively. The molecular tapes are connected via R₁²(5) couplings with two intermolecular N—H···O hydrogen bonds (Table 1), where both H atoms of chloranilic acid have transfered to the pyridine rings. In previous work (Zaman et al., 2000), we have shown that the flat molecular tapes form segregated stacks of each molecule. However, the overlaps between the chloranilate–pyridinium ring–benzene ring–pyridinium ring–chloranilate are observed in the stacks of the molecular tapes of (I). A short C—Cl···π interaction [Cl1···(C7≡C8) 3.440 (7), Cl1···C7 3.503 (4), Cl1···C8 3.480 (4) Å; Cl1···C7≡C8 79.1 (3) and Cl1···C8≡C7 81.3 (3)°] exists between the stacks of the molecular tapes (Reddy et al., 1996; Prasanna & Row, 2000). It is 1.7% shorter than the sum of the van der Waals radii of Cl and Csp² (Pauling, 1960).

S2. Experimental

1,4-Bis[(4-pyridyl)ethynyl]benzene was prepared according to the literature (Lin et al., 1995). Chloranilic acid was commercially available and purified by a usual method. A diffusion method for a solution of 1,4-bis[(4-pyridyl)ethynyl]benzene (0.02 mmol) and chloranilic acid (0.02 mmol) in acetonitrile (5 ml) using an H-tube gave crystals of (I) suitable for X-ray analysis.

S3. Refinement

All H atoms were localized in the Fourier map and were refined isotropically.

Computing details

Data collection: CAD-4 EXPRESS (Enraf-Nonius, 1992); cell refinement: CAD-4 EXPRESS; data reduction: HELENA (Spek, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPIII (Burnett & Johnson, 1996); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. The molecular structure of (I) with the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. Packing diagram of (I). Dotted lines show the intermolecular N—H···O hydrogen bonds.

1,4-bis[(4-pyridinium)ethynyl]benzene chloranilate

Crystal data

C20H14N2^2+·C6Cl2O4^2^−	Z = 1
Mr = 489.29	F(000) = 250
Triclinic, P1	Dx = 1.514 Mg m^−3
a = 7.6279 (9) Å	Cu Kα radiation, λ = 1.54178 Å
b = 8.4019 (10) Å	Cell parameters from 23 reflections
c = 8.6291 (4) Å	θ = 5.9–43.0°
α = 97.171 (6)°	µ = 3.05 mm^−1
β = 99.673 (6)°	T = 296 K
γ = 95.728 (10)°	Needle, dark red
V = 536.76 (9) Å^3	0.70 × 0.10 × 0.10 mm

Data collection

Enraf-Nonius CAD-4 diffractometer	1213 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.041
Graphite monochromator	θmax = 74.3°, θmin = 5.3°
ω–2θ scans	h = −9→9
Absorption correction: ψ scan (North et al., 1968)	k = −10→10
Tmin = 0.224, Tmax = 0.750	l = 0→10
2340 measured reflections	3 standard reflections every 120 reflections
2187 independent reflections	intensity decay: 2.5%

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.053	Hydrogen site location: difference Fourier map
wR(F^2) = 0.161	All H-atom parameters refined
S = 0.99
2187 reflections	(Δ/σ)max < 0.001
182 parameters	Δρmax = 0.29 e Å^−3
0 restraints	Δρmin = −0.37 e Å^−3

Special details

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.

Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)

6.1356 (0.0040) x + 4.1372 (0.0088) y - 3.1134 (0.0136) z = 2.5275 (0.0119)

* -0.0539 (0.0017) Cl1 * 0.0295 (0.0014) O1 * -0.0465 (0.0021) O2 * 0.0378 (0.0024) C1 * 0.0260 (0.0032) C2 * 0.0071 (0.0026) C3

Rms deviation of fitted atoms = 0.0367

5.5220 (0.0102) x + 4.9362 (0.0131) y - 3.4671 (0.0127) z = 1.6612 (0.0039)

Angle to previous plane (with approximate e.s.d.) = 7.25 (0.22)

* 0.0008 (0.0030) N1 * -0.0014 (0.0028) C9 * 0.0023 (0.0032) C10 * -0.0020 (0.0032) C11 * 0.0001 (0.0032) C12 * 0.0003 (0.0031) C13

Rms deviation of fitted atoms = 0.0014

4.3368 (0.0174) x + 6.0836 (0.0213) y - 3.8662 (0.0550) z = 1.3554 (0.0571)

Angle to previous plane (with approximate e.s.d.) = 11.78 (0.39)

* 0.0000 (0.0001) C4 * 0.0000 (0.0000) C5 * 0.0000 (0.0000) C6

Rms deviation of fitted atoms = 0.0000

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Cl1	0.20224 (16)	0.69132 (13)	0.52271 (10)	0.0753 (4)
O1	0.0000 (3)	0.7946 (3)	0.2345 (2)	0.0620 (8)
O2	−0.1897 (4)	1.0442 (3)	0.2169 (2)	0.0649 (8)
N1	0.2126 (5)	0.1379 (4)	0.0556 (3)	0.0629 (10)
C1	0.0961 (5)	0.8620 (4)	0.5109 (3)	0.0493 (9)
C2	0.0021 (5)	0.8856 (4)	0.3607 (3)	0.0461 (8)
C3	−0.1024 (5)	1.0290 (4)	0.3516 (3)	0.0467 (9)
C4	0.3538 (6)	0.5481 (5)	0.9087 (4)	0.0641 (12)
C5	0.4490 (5)	0.4367 (4)	0.8403 (3)	0.0499 (9)
C6	0.5969 (6)	0.3893 (5)	0.9317 (4)	0.0630 (12)
C7	0.3978 (5)	0.3700 (5)	0.6751 (3)	0.0561 (10)
C8	0.3564 (5)	0.3164 (5)	0.5379 (4)	0.0590 (11)
C9	0.3064 (5)	0.2549 (5)	0.3723 (3)	0.0532 (10)
C10	0.1842 (6)	0.3236 (6)	0.2743 (4)	0.0639 (12)
C11	0.1395 (7)	0.2608 (6)	0.1149 (4)	0.0676 (13)
C12	0.3313 (7)	0.0690 (5)	0.1468 (4)	0.0691 (13)
C13	0.3819 (6)	0.1250 (5)	0.3070 (4)	0.0653 (12)
H1	0.181 (8)	0.088 (8)	−0.065 (8)	0.14 (2)*
H4	0.244 (6)	0.583 (6)	0.857 (6)	0.093 (15)*
H6	0.670 (6)	0.309 (6)	0.896 (5)	0.080 (14)*
H10	0.128 (5)	0.407 (5)	0.307 (4)	0.053 (11)*
H11	0.065 (5)	0.303 (5)	0.064 (5)	0.059 (13)*
H12	0.391 (6)	−0.025 (6)	0.107 (5)	0.082 (14)*
H13	0.469 (6)	0.061 (5)	0.369 (5)	0.076 (13)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.1005 (9)	0.0774 (7)	0.0370 (5)	0.0335 (6)	−0.0130 (4)	−0.0172 (4)
O1	0.0873 (19)	0.0747 (17)	0.0156 (9)	0.0165 (15)	−0.0001 (10)	−0.0181 (10)
O2	0.094 (2)	0.0751 (17)	0.0159 (10)	0.0212 (15)	−0.0110 (11)	−0.0119 (10)
N1	0.085 (2)	0.078 (2)	0.0144 (12)	−0.0085 (18)	0.0026 (14)	−0.0115 (13)
C1	0.064 (2)	0.061 (2)	0.0161 (13)	0.0089 (17)	−0.0020 (13)	−0.0097 (13)
C2	0.059 (2)	0.056 (2)	0.0148 (12)	0.0004 (17)	−0.0007 (12)	−0.0116 (12)
C3	0.061 (2)	0.058 (2)	0.0141 (12)	0.0002 (17)	−0.0005 (12)	−0.0078 (12)
C4	0.077 (3)	0.091 (3)	0.0180 (14)	0.024 (2)	−0.0059 (16)	−0.0054 (16)
C5	0.070 (2)	0.058 (2)	0.0132 (12)	−0.0025 (17)	−0.0017 (13)	−0.0050 (12)
C6	0.090 (3)	0.072 (3)	0.0210 (15)	0.020 (2)	−0.0022 (17)	−0.0105 (15)
C7	0.074 (3)	0.070 (2)	0.0157 (13)	−0.0043 (19)	0.0026 (14)	−0.0089 (14)
C8	0.077 (3)	0.074 (3)	0.0174 (14)	−0.004 (2)	0.0020 (15)	−0.0089 (15)
C9	0.071 (3)	0.065 (2)	0.0140 (13)	−0.0136 (18)	0.0036 (14)	−0.0094 (13)
C10	0.080 (3)	0.079 (3)	0.0237 (16)	0.004 (2)	0.0015 (17)	−0.0155 (17)
C11	0.081 (3)	0.089 (3)	0.0201 (15)	0.002 (3)	−0.0083 (17)	−0.0069 (18)
C12	0.103 (4)	0.069 (3)	0.0260 (17)	0.006 (3)	0.0052 (19)	−0.0156 (16)
C13	0.099 (3)	0.064 (2)	0.0229 (16)	0.005 (2)	−0.0027 (18)	−0.0075 (15)

Geometric parameters (Å, º)

Cl1—C1	1.721 (4)	C5—C7	1.438 (3)
O1—C2	1.246 (3)	C6—C4^ii	1.386 (4)
O2—C3	1.266 (3)	C6—H6	0.97 (4)
N1—C11	1.311 (6)	C7—C8	1.190 (4)
N1—C12	1.324 (5)	C8—C9	1.431 (4)
N1—H1	1.05 (7)	C9—C10	1.371 (5)
C1—C3^i	1.397 (4)	C9—C13	1.386 (6)
C1—C2	1.419 (4)	C10—C11	1.382 (4)
C2—C3	1.513 (5)	C10—H10	0.90 (4)
C3—C1^i	1.397 (4)	C11—H11	0.80 (4)
C4—C5	1.376 (5)	C12—C13	1.379 (4)
C4—C6^ii	1.386 (4)	C12—H12	1.01 (5)
C4—H4	0.97 (5)	C13—H13	1.02 (4)
C5—C6	1.387 (5)
C11—N1—C12	121.0 (3)	C4^ii—C6—H6	114 (3)
C11—N1—H1	123 (3)	C5—C6—H6	126 (3)
C12—N1—H1	116 (3)	C8—C7—C5	179.2 (4)
C3^i—C1—C2	122.1 (3)	C7—C8—C9	179.0 (4)
C3^i—C1—Cl1	119.4 (2)	C10—C9—C13	118.4 (3)
C2—C1—Cl1	118.4 (2)	C10—C9—C8	121.0 (3)
O1—C2—C1	123.8 (3)	C13—C9—C8	120.6 (3)
O1—C2—C3	117.5 (3)	C9—C10—C11	119.3 (4)
C1—C2—C3	118.6 (2)	C9—C10—H10	124 (2)
O2—C3—C1^i	123.6 (3)	C11—C10—H10	117 (2)
O2—C3—C2	117.3 (3)	N1—C11—C10	121.3 (4)
C1^i—C3—C2	119.2 (3)	N1—C11—H11	124 (3)
C5—C4—C6^ii	120.4 (4)	C10—C11—H11	115 (3)
C5—C4—H4	126 (3)	N1—C12—C13	120.9 (4)
C6^ii—C4—H4	113 (3)	N1—C12—H12	124 (2)
C4—C5—C6	119.5 (3)	C13—C12—H12	115 (3)
C4—C5—C7	120.8 (3)	C12—C13—C9	119.2 (4)
C6—C5—C7	119.7 (3)	C12—C13—H13	116 (2)
C4^ii—C6—C5	120.0 (4)	C9—C13—H13	125 (2)
C3^i—C1—C2—O1	176.8 (4)	C4—C5—C6—C4^ii	1.1 (7)
Cl1—C1—C2—O1	−4.2 (5)	C7—C5—C6—C4^ii	−179.4 (4)
C3^i—C1—C2—C3	−3.2 (6)	C13—C9—C10—C11	0.5 (6)
Cl1—C1—C2—C3	175.7 (3)	C8—C9—C10—C11	179.9 (4)
O1—C2—C3—O2	2.2 (5)	C12—N1—C11—C10	0.4 (7)
C1—C2—C3—O2	−177.8 (3)	C9—C10—C11—N1	−0.5 (7)
O1—C2—C3—C1^i	−176.9 (3)	C11—N1—C12—C13	−0.2 (7)
C1—C2—C3—C1^i	3.1 (6)	N1—C12—C13—C9	0.1 (7)
C6^ii—C4—C5—C6	−1.1 (7)	C10—C9—C13—C12	−0.3 (6)
C6^ii—C4—C5—C7	179.4 (4)	C8—C9—C13—C12	−179.8 (4)

Symmetry codes: (i) −x, −y+2, −z+1; (ii) −x+1, −y+1, −z+2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1^iii	1.05 (7)	2.23 (6)	2.897 (4)	120 (5)
N1—H1···O2^iii	1.05 (7)	1.62 (7)	2.609 (3)	154 (5)

Symmetry code: (iii) −x, −y+1, −z.