4,4′-Azinodibenzoic acid

Abstract

The title compound, C₁₄H₁₀N₂O₄, shows crystallographic inversion symmetry and has one half-mol­ecule in the asymmetric unit. In the crystal, mol­ecules are linked into chains running along the cell diagonal by O—H⋯O hydrogen-bonding inter­actions.

Related literature

For the use of azodibenzoate-based systems as bridging aromatic carboxyl­ate ligands in coordination networks, see: Chen et al. (2008 ▶).

Experimental

Crystal data

• C₁₄H₁₀N₂O₄

• M _r = 270.16

• Triclinic,

• a = 3.772 (2) Å

• b = 6.322 (5) Å

• c = 12.692 (3) Å

• α = 79.323 (5)°

• β = 88.199 (4)°

• γ = 88.435 (5)°

• V = 297.2 (3) ų

• Z = 1

• Mo Kα radiation

• μ = 0.11 mm⁻¹

• T = 293 K

• 0.16 × 0.14 × 0.12 mm

Data collection

• Bruker SMART APEX CCD area-detector diffractometer

• Absorption correction: multi-scan (SADABS; Sheldrick 1996 ▶) T _min = 0.962, T _max = 0.971

• 2173 measured reflections

• 1351 independent reflections

• 786 reflections with I > 2σ(I)

• R _int = 0.017

Refinement

• R[F ² > 2σ(F ²)] = 0.040

• wR(F ²) = 0.100

• S = 0.86

• 1351 reflections

• 91 parameters

• H-atom parameters constrained

• Δρ_max = 0.19 e Å⁻³

• Δρ_min = −0.19 e Å⁻³

Data collection: SMART (Bruker, 1998 ▶); cell refinement: SAINT (Bruker, 1998 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1A⋯O2i	0.82	1.81	2.6181 (17)	170

Symmetry code: (i) .

supplementary crystallographic information

Comment

Azodibenzoate-based systems represent one type of bridging aromatic carboxylate ligand employed in the generation of coordination networks (Chen et al., 2008). There is half a molecule in the asymmetric unit of the title compound (Fig. 1). In the crystal, molecules are linked into chains by O—H···O hydrogen-bonding interactions (Table 2).

Experimental

A mixture of ZnCl₂^.2H₂O (0.5 mmol), 4,4'-azodibenzoatic acid (0.5 mmol), and H₂O (500 mmol) was heated at 140 ^oC for 3 days. After the mixture was slowly cooled to room temperature, pale yellow crystals of the title compound were yielded (22% yield).

Refinement

All H atoms on C atoms were positioned geometrically (C—H = 0.93 Å) and refined as riding, with U_iso(H)=1.2U_eq(carrier).

Figures

Fig. 1.

The structure of the title compound, showing the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. Symmetry code: (i) -x, -y, -z.

Crystal data

C14H10N2O4	Z = 1
Mr = 270.16	F(000) = 140
Triclinic, P1	Dx = 1.509 Mg m−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 3.772 (2) Å	Cell parameters from 1351 reflections
b = 6.322 (5) Å	θ = 3.0–29.0°
c = 12.692 (3) Å	µ = 0.11 mm−1
α = 79.323 (5)°	T = 293 K
β = 88.199 (4)°	Block, pale yellow
γ = 88.435 (5)°	0.16 × 0.14 × 0.12 mm
V = 297.2 (3) Å3

Data collection

Bruker SMART APEX CCD area-detector diffractometer	1351 independent reflections
Radiation source: fine-focus sealed tube	786 reflections with I > 2σ(I)
graphite	Rint = 0.017
φ and ω scans	θmax = 29.0°, θmin = 3.3°
Absorption correction: multi-scan (SADABS; Sheldrick 1996)	h = −5→4
Tmin = 0.962, Tmax = 0.971	k = −8→5
2173 measured reflections	l = −17→17

Refinement

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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.100	H-atom parameters constrained
S = 0.86	w = 1/[σ2(Fo2) + (0.0555P)2] where P = (Fo2 + 2Fc2)/3
1351 reflections	(Δ/σ)max < 0.001
91 parameters	Δρmax = 0.19 e Å−3
0 restraints	Δρmin = −0.19 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.

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
C1	0.0410 (4)	−0.0391 (3)	0.23081 (12)	0.0356 (4)
H1	−0.0514	−0.1767	0.2450	0.043*
C2	0.1284 (4)	0.0608 (3)	0.31492 (12)	0.0343 (4)
H2	0.0924	−0.0090	0.3855	0.041*
C3	0.2692 (4)	0.2646 (2)	0.29319 (11)	0.0292 (4)
C4	0.3691 (4)	0.3697 (2)	0.38301 (12)	0.0315 (4)
C5	0.3203 (4)	0.3700 (2)	0.18790 (12)	0.0337 (4)
H5	0.4147	0.5070	0.1738	0.040*
C6	0.2312 (4)	0.2720 (3)	0.10404 (12)	0.0355 (4)
H6	0.2640	0.3426	0.0334	0.043*
C7	0.0913 (4)	0.0659 (2)	0.12647 (12)	0.0315 (4)
N1	−0.0103 (4)	−0.0518 (2)	0.04644 (9)	0.0372 (4)
O1	0.2870 (4)	0.2717 (2)	0.47782 (9)	0.0545 (4)
H1A	0.3524	0.3417	0.5217	0.082*
O2	0.5255 (3)	0.54435 (18)	0.36449 (9)	0.0453 (4)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
C1	0.0452 (10)	0.0306 (9)	0.0329 (9)	−0.0099 (7)	−0.0026 (7)	−0.0095 (7)
C2	0.0438 (10)	0.0360 (9)	0.0243 (8)	−0.0081 (8)	−0.0014 (7)	−0.0072 (7)
C3	0.0321 (9)	0.0322 (8)	0.0261 (8)	−0.0037 (7)	−0.0030 (6)	−0.0115 (7)
C4	0.0377 (9)	0.0334 (9)	0.0253 (8)	−0.0060 (7)	−0.0040 (6)	−0.0092 (7)
C5	0.0436 (10)	0.0295 (8)	0.0299 (9)	−0.0082 (7)	−0.0009 (7)	−0.0092 (7)
C6	0.0465 (10)	0.0376 (9)	0.0240 (8)	−0.0067 (7)	−0.0030 (7)	−0.0084 (7)
C7	0.0333 (9)	0.0349 (9)	0.0299 (9)	−0.0023 (7)	−0.0048 (7)	−0.0144 (7)
N1	0.0471 (8)	0.0382 (8)	0.0300 (7)	−0.0081 (7)	−0.0058 (7)	−0.0143 (6)
O1	0.0875 (10)	0.0544 (8)	0.0254 (6)	−0.0314 (7)	−0.0023 (6)	−0.0128 (6)
O2	0.0674 (8)	0.0397 (7)	0.0321 (7)	−0.0215 (6)	−0.0027 (6)	−0.0119 (5)

Geometric parameters (Å, °)

C1—C7	1.377 (2)	C4—O1	1.2800 (18)
C1—C2	1.389 (2)	C5—C6	1.381 (2)
C1—H1	0.9300	C5—H5	0.9300
C2—C3	1.384 (2)	C6—C7	1.396 (2)
C2—H2	0.9300	C6—H6	0.9300
C3—C5	1.388 (2)	C7—N1	1.4327 (19)
C3—C4	1.485 (2)	N1—N1i	1.239 (2)
C4—O2	1.246 (2)	O1—H1A	0.8200
C7—C1—C2	119.91 (16)	C6—C5—C3	120.22 (15)
C7—C1—H1	120.0	C6—C5—H5	119.9
C2—C1—H1	120.0	C3—C5—H5	119.9
C3—C2—C1	119.70 (15)	C5—C6—C7	119.22 (15)
C3—C2—H2	120.2	C5—C6—H6	120.4
C1—C2—H2	120.2	C7—C6—H6	120.4
C2—C3—C5	120.28 (14)	C1—C7—C6	120.67 (14)
C2—C3—C4	119.73 (14)	C1—C7—N1	115.05 (15)
C5—C3—C4	119.99 (15)	C6—C7—N1	124.28 (14)
O2—C4—O1	123.10 (14)	N1i—N1—C7	114.04 (17)
O2—C4—C3	120.27 (14)	C4—O1—H1A	109.5
O1—C4—C3	116.63 (15)

Symmetry codes: (i) −x, −y, −z.

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1A···O2ii	0.82	1.81	2.6181 (17)	170

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