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Acta Cryst. (2008). E64, o595    [ doi:10.1107/S1600536808004108 ]

(E)-2-{Ethyl[4-(4-nitrophenyldiazenyl)phenyl]amino}ethyl anthracene-9-carboxylate

M. A. Rodriguez, T. Zifer, A. L. Vance, B. M. Wong and F. Leonard

Abstract top

The crystal structure of the title compound, C31H26N4O4, displays a trans conformation for the nitrophenyldiazenyl portion of the molecule. Packing diagrams indicate that weak C-H...O hydrogen bonds, likely associated with a strong dipole moment present in the molecule, dictate the arrangement of molecules in the crystal structure.

Comment top

Figure 1 shows an atomic displacement ellipsoid plot of the title compound (I). (I) is a merger of 9-anthracenecarboxylic acid and 4-[N-(2-hydroxyethyl)-N-ethyl]-amino-4'-nitroazobenzene which is better known as Disperse Red 1 or (DR1). In (I) the azobenzene-based DR1 takes on the trans conformational state. Atassi et al. (1998) has documented photoisomerization to a cis conformation under UV light with decay back to the equilibrium trans species upon removal of the UV stimulus. (I) has three terminal oxygen atoms: O2, O3 and O4. All three of these atoms display double bonds, O2 being a remnant of anthracene and O3 and O4 at the termination of the nitroazobenzene. The C15=O2 bond length is 1.207 (3)Å while O3=N4 and O4=N4 are slightly longer at 1.230 (3) and 1.229 (3) Å, respectively. All other bond lengths (C—C, C—N, N=N, and C—O) in (I) were consistent with expected values.

Figure 2 shows a packing arrangement of two molecules of (I). The two molecules are related by inversion, consistent with the P-1 space group and the nitroazobenzene portion of (I) is positioned close to the a-c plane of the unit cell. Weak C—H···O hydrogen bonds are observed from O3 to H1—C1 of a neighboring molecule, with an intermolecular O3···H1 distance of 2.559 Å. Likewise, O4 shows similar weak hydrogen bonding to H3—C3 and H16—C16 of a neighboring molecule with intermolecular distances of 2.652 and 2.611 Å, respectively. These weak C—H···O hydrogen bonds generate a supramolecular head-to-tail dimer via the nitro groups that terminate each molecule. Atassi, et al. (1998) has calculated the dipole moment for the trans form of DR1 to be about 9D. Since compound (I) contains the DR1 molecule, it is reasonable to presume a comparable dipole presence for (I). Our calculations of the geometry and dipole moment for compound (I) using a three-parameter hybrid functional (B3LYP) with the 6–311 G(d,p) basis set (Becke, 1993) yielded a value of 11.8 D. This relatively strong dipole likely plays a role in the head-to-tail alignment of the molecules as viewed in Figure 2.

Figure 3 shows a packing diagram for (I) which illustrates the supramolecular interactions along the b axis of the unit cell. Again we can see the inversion symmetry for the two molecules of (I) and see that the carbonyl O2 atom is coordinated to H21—C21 of a neighboring molecule with an intermolecular distance of 2.307 Å. This is shorter than for interactions observed in figure 2 and likely indicates a more rigid C—H···O interaction along the b axis.

Related literature top

Simmons et al. (2007) describe the use of the title compound in the fabrication of carbon nanotubes with optically modulated electronic conduction. Sekkat et al. (1992) document the use of Disperse Red 1 for reversible photoisomerization in thin films.

For related literature, see: Atassi et al. (1998); Becke (1993).

Experimental top

The title compound was obtained using the published synthetic procedure of Simmons, et al. (2007). The product was synthesized from 9-anthracenecarboxylic acid and Disperse red 1 via a dicylcohexylcarbodiimide esterification in anhydrous dichloromethane. Following purification by silica gel chromatography with chloroform eluent, the dark red powder was characterized by 1H-NMR, UV/Vis and FTIR. Crystals were obtained by re-crystallization from acetonitrile/ethanol.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SMART (Bruker, 1998); data reduction: SAINT-Plus (Bruker, 2001); program(s) used to solve structure: SHELXTL (Version 6.10; Sheldrick, 2008); program(s) used to refine structure: XSHELL (Bruker, 2000); molecular graphics: XSHELL (Bruker, 2000) and Mercury (Version 1.4; Macrae et al., 2006); software used to prepare material for publication: SHELXTL (Version 6.10; Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), with atom labels and 50% probability displacement ellipsoids for non-H atoms.
[Figure 2] Fig. 2. Packing of (I) as viewed down the a axis illustrating weak C—H···O hydrogen bonding associated with terminal O atoms O3 and O4. The nitroasobenzene portion of (I) resides near the a-c plane of the unit cell.
[Figure 3] Fig. 3. Packing diagram of (I) viewed down the a axis illustrating weak hydrogen bonding between the carbonyl oxygen (O2) and the neighboring molecule of (I). This interaction dictates the packing behavior of (I) along the b axis.
(E)-2-{Ethyl[4-(4-nitrophenyldiazenyl)phenyl]amino}ethyl anthracene-9-carboxylate top
Crystal data top
C31H26N4O4Z = 2
Mr = 518.56F000 = 544
Triclinic, P1Dx = 1.388 Mg m−3
Hall symbol: -P 1Mo Kα radiation
λ = 0.71073 Å
a = 9.3161 (9) ÅCell parameters from 100 reflections
b = 10.6586 (10) Åθ = 1.6–26.0º
c = 13.5328 (13) ŵ = 0.09 mm−1
α = 101.134 (3)ºT = 173 (2) K
β = 104.667 (4)ºIrregular, orange
γ = 99.779 (3)º0.20 × 0.08 × 0.06 mm
V = 1241.2 (2) Å3
Data collection top
Bruker SMART CCD area-detector
diffractometer		4824 independent reflections
Radiation source: fine-focus sealed tube2786 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.050
Detector resolution: 0 pixels mm-1θmax = 26.0º
T = 173(2) Kθmin = 1.6º
phi and ω scansh = −11→11
Absorption correction: multi-scan
(SADABS; Sheldrick, 1999)		k = −13→13
Tmin = 0.982, Tmax = 0.994l = −16→16
9650 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.066H-atom parameters constrained
wR(F2) = 0.123  w = 1/[σ2(Fo2) + (0.0333P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max = 0.001
4824 reflectionsΔρmax = 0.21 e Å−3
353 parametersΔρmin = −0.21 e Å−3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
C31H26N4O4γ = 99.779 (3)º
Mr = 518.56V = 1241.2 (2) Å3
Triclinic, P1Z = 2
a = 9.3161 (9) ÅMo Kα
b = 10.6586 (10) ŵ = 0.09 mm−1
c = 13.5328 (13) ÅT = 173 (2) K
α = 101.134 (3)º0.20 × 0.08 × 0.06 mm
β = 104.667 (4)º
Data collection top
Bruker SMART CCD area-detector
diffractometer		4824 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1999)		2786 reflections with I > 2σ(I)
Tmin = 0.982, Tmax = 0.994Rint = 0.050
9650 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.066353 parameters
wR(F2) = 0.123H-atom parameters constrained
S = 1.02Δρmax = 0.21 e Å−3
4824 reflectionsΔρmin = −0.21 e Å−3
Special details top

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 (Å2) top
xyzUiso*/Ueq
C10.4311 (4)0.4301 (3)1.1818 (2)0.0357 (8)
H10.35520.38781.11670.043*
C20.3871 (4)0.4647 (3)1.2740 (2)0.0380 (8)
H20.28230.44551.27050.046*
C30.5796 (3)0.4565 (3)1.1849 (2)0.0314 (8)
H30.60660.43321.12180.038*
C40.4936 (3)0.5249 (3)1.3672 (2)0.0330 (8)
H40.46240.54861.42850.040*
C50.6965 (3)0.5190 (3)1.2820 (2)0.0256 (7)
C60.6513 (3)0.5536 (3)1.3752 (2)0.0267 (7)
C70.8515 (3)0.5491 (3)1.2887 (2)0.0233 (7)
C80.7638 (3)0.6146 (3)1.4708 (2)0.0295 (8)
H80.73390.63711.53280.035*
C90.9635 (3)0.6111 (3)1.3845 (2)0.0262 (7)
C100.9183 (3)0.6438 (3)1.4782 (2)0.0271 (7)
C111.1225 (3)0.6452 (3)1.3946 (2)0.0308 (8)
H111.15600.62501.33390.037*
C121.0315 (4)0.7073 (3)1.5759 (2)0.0363 (8)
H121.00170.72921.63800.044*
C131.2262 (4)0.7058 (3)1.4892 (3)0.0385 (9)
H131.33130.72791.49380.046*
C141.1804 (4)0.7369 (3)1.5816 (3)0.0404 (9)
H141.25480.77851.64760.049*
C150.8955 (3)0.5179 (3)1.1890 (2)0.0262 (7)
C160.9915 (3)0.3710 (3)1.0822 (2)0.0283 (7)
H16A1.08230.43721.08560.034*
H16B0.90860.36721.01850.034*
C171.0292 (3)0.2372 (3)1.0778 (2)0.0306 (8)
H17A1.10230.22861.03640.037*
H17B1.08080.23341.15030.037*
C180.8293 (4)0.0686 (3)1.1033 (2)0.0326 (8)
H18A0.90520.09191.17390.039*
H18B0.8035−0.02831.07770.039*
C190.6864 (4)0.1132 (3)1.1141 (2)0.0384 (9)
H19A0.71240.20811.14540.058*
H19B0.64280.06701.15950.058*
H19C0.61170.09341.04430.058*
C200.8434 (3)0.0764 (3)0.9246 (2)0.0252 (7)
C210.9076 (3)0.1361 (3)0.8559 (2)0.0271 (7)
H210.98500.21480.88460.032*
C220.8607 (3)0.0830 (3)0.7490 (2)0.0274 (7)
H220.90830.12380.70530.033*
C230.7442 (3)−0.0300 (3)0.7038 (2)0.0248 (7)
C240.6742 (3)−0.0860 (3)0.7695 (2)0.0275 (7)
H240.5922−0.16140.73940.033*
C250.7210 (3)−0.0349 (3)0.8769 (2)0.0259 (7)
H250.6704−0.07500.91950.031*
C260.6993 (3)−0.0968 (3)0.4302 (2)0.0248 (7)
C270.7983 (3)−0.1047 (3)0.3689 (2)0.0271 (7)
H270.9051−0.07330.40090.033*
C280.7414 (3)−0.1583 (3)0.2614 (2)0.0270 (7)
H280.8081−0.16630.21900.032*
C290.5850 (3)−0.1999 (3)0.2170 (2)0.0255 (7)
C300.4844 (3)−0.1891 (3)0.2755 (2)0.0303 (8)
H300.3775−0.21720.24270.036*
C310.5424 (3)−0.1365 (3)0.3829 (2)0.0298 (7)
H310.4751−0.12740.42460.036*
N10.8986 (3)0.1256 (2)1.03191 (18)0.0281 (6)
N20.6851 (3)−0.0883 (2)0.59401 (18)0.0278 (6)
N30.7671 (3)−0.0435 (2)0.54054 (18)0.0281 (6)
N40.5237 (3)−0.2560 (2)0.10309 (19)0.0333 (7)
O10.9436 (2)0.40590 (19)1.17640 (14)0.0297 (5)
O20.8885 (3)0.5849 (2)1.12621 (17)0.0432 (6)
O30.6111 (3)−0.2485 (2)0.04881 (16)0.0490 (7)
O40.3869 (3)−0.3075 (2)0.06570 (16)0.0461 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.030 (2)0.0329 (19)0.036 (2)0.0005 (16)0.0081 (16)−0.0016 (16)
C20.030 (2)0.035 (2)0.046 (2)0.0021 (16)0.0162 (17)0.0015 (17)
C30.036 (2)0.0261 (18)0.0289 (18)0.0055 (15)0.0106 (16)−0.0005 (14)
C40.036 (2)0.0326 (19)0.035 (2)0.0098 (16)0.0191 (17)0.0063 (16)
C50.0308 (19)0.0178 (16)0.0267 (18)0.0049 (14)0.0099 (15)0.0010 (13)
C60.0305 (19)0.0233 (17)0.0282 (18)0.0062 (14)0.0133 (15)0.0046 (14)
C70.0281 (18)0.0186 (16)0.0264 (17)0.0059 (13)0.0135 (14)0.0054 (13)
C80.040 (2)0.0282 (18)0.0238 (17)0.0098 (15)0.0150 (16)0.0049 (14)
C90.0315 (19)0.0203 (16)0.0285 (18)0.0071 (14)0.0084 (15)0.0096 (14)
C100.0320 (19)0.0227 (17)0.0256 (18)0.0058 (14)0.0084 (15)0.0045 (14)
C110.0299 (19)0.0324 (19)0.0326 (19)0.0089 (15)0.0110 (16)0.0100 (15)
C120.043 (2)0.036 (2)0.0251 (18)0.0072 (17)0.0068 (16)0.0028 (15)
C130.029 (2)0.036 (2)0.047 (2)0.0041 (16)0.0076 (17)0.0102 (17)
C140.044 (2)0.035 (2)0.032 (2)0.0020 (17)0.0012 (17)0.0036 (16)
C150.0232 (18)0.0212 (17)0.0312 (19)0.0026 (14)0.0074 (15)0.0027 (14)
C160.0292 (18)0.0356 (19)0.0184 (16)0.0067 (15)0.0081 (14)0.0021 (14)
C170.0261 (18)0.0376 (19)0.0230 (17)0.0103 (15)0.0047 (14)−0.0035 (15)
C180.043 (2)0.0314 (19)0.0253 (18)0.0130 (16)0.0100 (16)0.0077 (15)
C190.046 (2)0.035 (2)0.036 (2)0.0086 (17)0.0176 (17)0.0064 (16)
C200.0260 (18)0.0265 (18)0.0263 (18)0.0137 (14)0.0094 (15)0.0052 (14)
C210.0234 (17)0.0249 (17)0.0292 (18)0.0042 (14)0.0072 (14)0.0000 (14)
C220.0256 (18)0.0321 (18)0.0276 (18)0.0088 (15)0.0114 (14)0.0076 (15)
C230.0248 (17)0.0263 (17)0.0204 (17)0.0071 (14)0.0052 (14)0.0003 (13)
C240.0282 (18)0.0263 (17)0.0242 (17)0.0053 (14)0.0061 (14)0.0007 (14)
C250.0292 (18)0.0249 (17)0.0242 (17)0.0075 (14)0.0095 (14)0.0046 (14)
C260.0329 (19)0.0179 (16)0.0247 (17)0.0092 (14)0.0085 (15)0.0048 (13)
C270.0248 (17)0.0273 (17)0.0256 (18)0.0035 (14)0.0053 (14)0.0033 (14)
C280.0268 (18)0.0322 (18)0.0250 (18)0.0079 (15)0.0095 (14)0.0104 (14)
C290.0332 (19)0.0233 (17)0.0178 (16)0.0077 (14)0.0045 (14)0.0032 (13)
C300.0271 (18)0.0328 (19)0.0285 (18)0.0077 (15)0.0050 (15)0.0056 (15)
C310.0293 (19)0.0346 (19)0.0268 (18)0.0101 (15)0.0096 (15)0.0070 (15)
N10.0309 (16)0.0331 (15)0.0189 (14)0.0075 (12)0.0072 (12)0.0028 (12)
N20.0308 (15)0.0296 (15)0.0245 (15)0.0111 (12)0.0093 (12)0.0049 (12)
N30.0306 (16)0.0308 (15)0.0218 (14)0.0083 (12)0.0070 (12)0.0037 (12)
N40.0376 (18)0.0333 (16)0.0253 (16)0.0071 (14)0.0045 (14)0.0064 (13)
O10.0383 (13)0.0302 (12)0.0231 (12)0.0128 (10)0.0121 (10)0.0043 (10)
O20.0657 (17)0.0346 (14)0.0456 (15)0.0187 (12)0.0329 (13)0.0194 (12)
O30.0528 (16)0.0625 (17)0.0281 (13)0.0052 (13)0.0163 (12)0.0045 (12)
O40.0316 (14)0.0597 (16)0.0327 (14)0.0039 (12)−0.0035 (11)0.0011 (12)
Geometric parameters (Å, °) top
C1—C31.352 (4)C18—N11.460 (3)
C1—C21.411 (4)C18—C191.519 (4)
C1—H10.9500C18—H18A0.9900
C2—C41.350 (4)C18—H18B0.9900
C2—H20.9500C19—H19A0.9800
C3—C51.431 (4)C19—H19B0.9800
C3—H30.9500C19—H19C0.9800
C4—C61.421 (4)C20—N11.373 (3)
C4—H40.9500C20—C251.413 (4)
C5—C71.400 (4)C20—C211.416 (4)
C5—C61.431 (4)C21—C221.373 (4)
C6—C81.397 (4)C21—H210.9500
C7—C91.399 (4)C22—C231.392 (4)
C7—C151.500 (4)C22—H220.9500
C8—C101.394 (4)C23—C241.392 (4)
C8—H80.9500C23—N21.418 (3)
C9—C111.429 (4)C24—C251.376 (4)
C9—C101.433 (4)C24—H240.9500
C10—C121.422 (4)C25—H250.9500
C11—C131.354 (4)C26—C271.391 (4)
C11—H110.9500C26—C311.391 (4)
C12—C141.349 (4)C26—N31.423 (3)
C12—H120.9500C27—C281.381 (4)
C13—C141.418 (4)C27—H270.9500
C13—H130.9500C28—C291.384 (4)
C14—H140.9500C28—H280.9500
C15—O21.207 (3)C29—C301.378 (4)
C15—O11.341 (3)C29—N41.463 (3)
C16—O11.457 (3)C30—C311.379 (4)
C16—C171.519 (4)C30—H300.9500
C16—H16A0.9900C31—H310.9500
C16—H16B0.9900N2—N31.275 (3)
C17—N11.457 (3)N4—O41.229 (3)
C17—H17A0.9900N4—O31.230 (3)
C17—H17B0.9900
C3—C1—C2120.9 (3)N1—C18—C19114.1 (3)
C3—C1—H1119.5N1—C18—H18A108.7
C2—C1—H1119.5C19—C18—H18A108.7
C4—C2—C1120.2 (3)N1—C18—H18B108.7
C4—C2—H2119.9C19—C18—H18B108.7
C1—C2—H2119.9H18A—C18—H18B107.6
C1—C3—C5120.9 (3)C18—C19—H19A109.5
C1—C3—H3119.6C18—C19—H19B109.5
C5—C3—H3119.6H19A—C19—H19B109.5
C2—C4—C6121.2 (3)C18—C19—H19C109.5
C2—C4—H4119.4H19A—C19—H19C109.5
C6—C4—H4119.4H19B—C19—H19C109.5
C7—C5—C6119.2 (3)N1—C20—C25122.4 (3)
C7—C5—C3122.8 (3)N1—C20—C21121.0 (3)
C6—C5—C3118.0 (3)C25—C20—C21116.6 (3)
C8—C6—C4122.4 (3)C22—C21—C20121.7 (3)
C8—C6—C5118.9 (3)C22—C21—H21119.2
C4—C6—C5118.8 (3)C20—C21—H21119.2
C9—C7—C5121.6 (3)C21—C22—C23120.8 (3)
C9—C7—C15120.1 (3)C21—C22—H22119.6
C5—C7—C15118.2 (3)C23—C22—H22119.6
C10—C8—C6122.2 (3)C22—C23—C24118.4 (3)
C10—C8—H8118.9C22—C23—N2124.4 (3)
C6—C8—H8118.9C24—C23—N2117.1 (3)
C7—C9—C11123.4 (3)C25—C24—C23121.6 (3)
C7—C9—C10119.1 (3)C25—C24—H24119.2
C11—C9—C10117.5 (3)C23—C24—H24119.2
C8—C10—C12121.6 (3)C24—C25—C20120.8 (3)
C8—C10—C9118.9 (3)C24—C25—H25119.6
C12—C10—C9119.5 (3)C20—C25—H25119.6
C13—C11—C9121.1 (3)C27—C26—C31120.1 (3)
C13—C11—H11119.5C27—C26—N3116.6 (3)
C9—C11—H11119.5C31—C26—N3123.3 (3)
C14—C12—C10121.0 (3)C28—C27—C26120.0 (3)
C14—C12—H12119.5C28—C27—H27120.0
C10—C12—H12119.5C26—C27—H27120.0
C11—C13—C14121.0 (3)C27—C28—C29118.5 (3)
C11—C13—H13119.5C27—C28—H28120.8
C14—C13—H13119.5C29—C28—H28120.8
C12—C14—C13120.0 (3)C30—C29—C28122.6 (3)
C12—C14—H14120.0C30—C29—N4118.6 (3)
C13—C14—H14120.0C28—C29—N4118.8 (3)
O2—C15—O1123.0 (3)C29—C30—C31118.5 (3)
O2—C15—C7124.5 (3)C29—C30—H30120.8
O1—C15—C7112.4 (3)C31—C30—H30120.8
O1—C16—C17107.3 (2)C30—C31—C26120.3 (3)
O1—C16—H16A110.3C30—C31—H31119.9
C17—C16—H16A110.3C26—C31—H31119.9
O1—C16—H16B110.3C20—N1—C17120.5 (2)
C17—C16—H16B110.3C20—N1—C18121.5 (2)
H16A—C16—H16B108.5C17—N1—C18118.0 (2)
N1—C17—C16115.0 (2)N3—N2—C23113.5 (2)
N1—C17—H17A108.5N2—N3—C26112.1 (2)
C16—C17—H17A108.5O4—N4—O3122.8 (3)
N1—C17—H17B108.5O4—N4—C29118.6 (3)
C16—C17—H17B108.5O3—N4—C29118.6 (3)
H17A—C17—H17B107.5C15—O1—C16115.4 (2)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C1—H1···O3i0.952.563.230 (4)128
C3—H3···O4i0.952.653.570 (4)163
C16—H16B···O4i0.992.613.462 (4)144
C21—H21···O2ii0.952.313.176 (4)152
Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+2, −y+1, −z+2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C1—H1···O3i0.952.563.230 (4)128
C3—H3···O4i0.952.653.570 (4)163
C16—H16B···O4i0.992.613.462 (4)144
C21—H21···O2ii0.952.313.176 (4)152
Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+2, −y+1, −z+2.
Acknowledgements top

Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under contract DE—AC04–94 A L85000.

references
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