4-{(E)-2-[4-(But-3-en-1-yl­oxy)phen­yl]diazen-1-yl}benzoic acid

Rahman, M.L.; Kwong, H.C.; Mohd. Yusoff, M.; Hegde, G.; Mohamed Tahir, M.I.; Rahman, M.Z.A.

doi:10.1107/S1600536812038718

organic compounds

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ISSN: 2056-9890

Volume 68| Part 10| October 2012| Page o2958

https://doi.org/10.1107/S1600536812038718

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4-{(E)-2-[4-(But-3-en-1-yloxy)phenyl]diazen-1-yl}benzoic acid

Md. Lutfor Rahman,^a ^* Huey Chong Kwong,^b Mashitah Mohd. Yusoff,^a Gurumurthy Hegde,^a Mohamed Ibrahim Mohamed Tahir ^b and Mohamad Zaki. Ab. Rahman ^b

^aUniversity Malaysia Pahang, Faculty of Industrial Sciences and Technology, 26300 Gambang, Kuantan, Pahang, Malaysia, and ^bDepartment of Chemistry, Faculty Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
^*Correspondence e-mail: lutfor73@gmail.com

(Received 9 July 2012; accepted 10 September 2012; online 19 September 2012)

The title compound, C₁₇H₁₆N₂O₃, has an E conformation about the azobenzene (–N=N–) linkage. The benzene rings are twisted slightly with respect to each other [6.79 (9)°], while the dihedral angle between the plane through the carboxy group and the attached benzene ring is 3.2 (2)°. In the crystal, molecules are oriented with the carboxy groups head-to-head, forming O—H⋯O hydrogen-bonded inversion dimers. These dimers are connected by C—H⋯O hydrogen-bonds into layers lying parallel to the (013) plane.

Related literature

For the physical properties of compounds containing an azobenzene (–N=N–) linkage, see: Chigrinov (2005 ); Hegde (2007 ). For related structures, see: Yu & Liu (2009 ); Lai et al. (2002 ); Centore & Tuzi (2003 ). For standard bond lengths, see Allen et al. (1987 ).

Experimental

Crystal data

C₁₇H₁₆N₂O₃
M_r = 296.33
Triclinic, $[P \overline 1]$
a = 7.0937 (7) Å
b = 9.8687 (10) Å
c = 11.2490 (11) Å
α = 87.334 (8)°
β = 73.475 (8)°
γ = 75.174 (8)°
V = 729.54 (13) Å³
Z = 2
Cu Kα radiation
μ = 0.77 mm⁻¹
T = 100 K
0.26 × 0.16 × 0.04 mm

Data collection

Oxford Diffraction Gemini diffractometer
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ) T_min = 0.85, T_max = 0.97
9940 measured reflections
2783 independent reflections
2298 reflections with I > 2.0σ(I)
R_int = 0.024

Refinement

R[F² > 2σ(F²)] = 0.054
wR(F²) = 0.146
S = 1.00
2773 reflections
199 parameters
H-atom parameters constrained
Δρ_max = 0.51 e Å⁻³
Δρ_min = −0.33 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H2⋯O1ⁱ	0.87	1.76	2.612 (3)	166 (1)
C21—H211⋯O1ⁱⁱ	0.95	2.50	3.275 (3)	139 (1)
Symmetry codes: (i) -x, -y+3, -z; (ii) x+1, y, z.

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ); cell refinement: CrysAlis CCD; data reduction: CrysAlis RED (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ ); program(s) used to solve structure: Superflip (Palatinus & Chapuis, 2007 ); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003 ); molecular graphics: Mercury (Macrae et al., 2006 ); software used to prepare material for publication: CRYSTALS.

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536812038718/su2476sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812038718/su2476Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536812038718/su2476Isup3.cml

checkCIF report

Comment top

An in a molecule introduces the possibility of photochromism and photoisomerization (Chigrinov, 2005). Photonics, in which the light can be controlled by light as stimulus has been exploited (Hegde, 2007). Upon absorption of UV light (~ 365 nm) the energetically more stable E conformation, transforms into the Z conformation. The reverse transformation of the Z isomer into the E isomer can be brought about by irradiation with visible light (in the range of 400–500 nm). The latter can also occur in the "dark" by a process known as "thermal back relaxation" in a period ranging from minutes to tens of hours depending on the system. In this case molecules again transform from the metastable cis-conformation to the energetically stable trans-conformation. In conclusion, the present investigation on rod-shaped azo dyes is very useful for a variety of photonic applications. Excellent quality, cost effective, easy to prepare, are properties which make these devices very attractive for future generations. Detailed investigations on the physics of these azo dyes is under intense consideration.

The bond lengths (Allen et al.,1987) and bond angles in the titled compound (Fig. 1) are normal. The carbonyl group (C2/O1/O3) is almost coplanar with the attached benzene ring (C4-C7/C21/C22) with a dihedral angle of only 3.2 (2)°. The length of N8═N9 bond is 1.263 (2) Å and the torsion angle for the azo unit (C7—N8—N9—C10) is -177.75 (16)° rather than ca. ±180° as observed elsewhere: For example: 4,4-Azinodibenzoic acid (Yu and Liu, 2009) and (E)-ethyl 4-((4-(decanoyloxy)phenyl)diazenyl)benzoate (Lai et al.,2002). However, it is comparable with the value of 175.10° observed for (E)-4-((4-((2-hydroxyethyl)(methyl)amino)phenyl)diazenyl)benzoic acid (Centore & Tuzi, 2003). The benzene rings (C4-C7/C21/C22 and C10-C3/C19/C20) lie at a mutual dihedral angles of 6.79 (9)°, compared to 16.69° in (E)-4-((4-((2-hydroxyethyl)(methyl)amino)phenyl)diazenyl)benzoic acid (Centore & Tuzi, 2003). The C15—C16—C17—C18 torsion angle in the butyl group is 126.1 (3)°.

In the crystal, the carboxyl groups are oriented head-to-head forming hydrogen bonded inversion dimers (Table 1 and Fig. 2). These dimers are further linked by C—H···O hydrogen bonds to a generate a layer parallel to the (013) plane (Table 1 and Fig. 2).

Related literature top

For the physical properties of compounds containing an azobenzene (–N=N–) linkage, see: Chigrinov (2005); Hegde (2007). For related structures, see: Yu & Liu (2009); Lai et al. (2002); Centore & Tuzi (2003). For standard bond lengths, see Allen et al. (1987).

Experimental top

The title compound was prepared from ethyl 4-aminobenzoate. Firstly the diazonuim salt was prepared using one equivalent of sodium nitrite to one equivalent of ethyl 4-aminobenzoate in methanol - water mixture at 275 K, in the presence of 3 equivalents of aqueous hydrochloric acid, which was coupled with phenol to yield ethyl 4-[(4-hydroxyphenyl)diazenyl]benzoate. This compound was then alkylated with 4-bromo-1-butene in the presence of potassium carbonate as base to give the ester, ethyl 4-{[4-(but-3-en-1-yloxy)phenyl]diazenyl}benzoate. This compound was then hydrolyzed under basic conditions to yield the title benzoic acid. Brown plate-like crystals of the title compound were obtained by slow evaporation of a solution in methanol.

Structure description top

For the physical properties of compounds containing an azobenzene (–N=N–) linkage, see: Chigrinov (2005); Hegde (2007). For related structures, see: Yu & Liu (2009); Lai et al. (2002); Centore & Tuzi (2003). For standard bond lengths, see Allen et al. (1987).

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis CCD (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: Superflip (Palatinus & Chapuis, 2007); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: Mercury (Macrae et al., 2006); software used to prepare material for publication: CRYSTALS (Betteridge et al., 2003).

Figures top

	Fig. 1. The molecular structure of the title molecule with the atom numbering and displacement ellipsoids drawn at the 50% probability level.
	Fig. 2. A view along the c axis of the crystal packing of the title compound, with the hydrogen bonds shown as dashed lines [the C-bound H atoms have been omitted for clarity].

4-{(E)-2-[4-(But-3-en-1-yloxy)phenyl]diazen-1-yl}benzoic acid top

Crystal data top

C₁₇H₁₆N₂O₃	Z = 2
M_r = 296.33	F(000) = 312
Triclinic, P1	D_x = 1.349 Mg m⁻³
Hall symbol: -P 1	Cu Kα radiation, λ = 1.54180 Å
a = 7.0937 (7) Å	Cell parameters from 3768 reflections
b = 9.8687 (10) Å	θ = 4–71°
c = 11.2490 (11) Å	µ = 0.77 mm⁻¹
α = 87.334 (8)°	T = 100 K
β = 73.475 (8)°	Plate, brown
γ = 75.174 (8)°	0.26 × 0.16 × 0.04 mm
V = 729.54 (13) Å³

Data collection top

Oxford Diffraction Gemini diffractometer	2783 independent reflections
Radiation source: sealed x-ray tube	2298 reflections with I > 2.0σ(I)
Graphite monochromator	R_int = 0.024
ω scans	θ_max = 71.5°, θ_min = 4.1°
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	h = −8→8
T_min = 0.85, T_max = 0.97	k = −11→11
9940 measured reflections	l = −13→13

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F² > 2σ(F²)] = 0.054	H-atom parameters constrained
wR(F²) = 0.146	Method = Modified Sheldrick w = 1/[σ²(F²) + ( 0.06P)² + 0.76P], where P = (max(F_o²,0) + 2F_c²)/3
S = 1.00	(Δ/σ)_max = 0.0003776
2773 reflections	Δρ_max = 0.51 e Å⁻³
199 parameters	Δρ_min = −0.33 e Å⁻³
0 restraints

Crystal data top

C₁₇H₁₆N₂O₃	γ = 75.174 (8)°
M_r = 296.33	V = 729.54 (13) Å³
Triclinic, P1	Z = 2
a = 7.0937 (7) Å	Cu Kα radiation
b = 9.8687 (10) Å	µ = 0.77 mm⁻¹
c = 11.2490 (11) Å	T = 100 K
α = 87.334 (8)°	0.26 × 0.16 × 0.04 mm
β = 73.475 (8)°

Data collection top

Oxford Diffraction Gemini diffractometer	2783 independent reflections
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006)	2298 reflections with I > 2.0σ(I)
T_min = 0.85, T_max = 0.97	R_int = 0.024
9940 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.054	0 restraints
wR(F²) = 0.146	H-atom parameters constrained
S = 1.00	Δρ_max = 0.51 e Å⁻³
2773 reflections	Δρ_min = −0.33 e Å⁻³
199 parameters

Special details top

Refinement. This compound, 9940 numbers of reflections were collected and measured during the refinement. Symmetry related reflections were measured more than once and after merging the symmetry equivalent reflections there were only 2783 reflection left. 10 more reflections were filtered, as sigma cutoff was set as 3 and (sinθ/x)set to>0.01 (to eliminate reflection measured near the vicinity of beam stop) therefore numbers of reflection reduced to 2773.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.0122 (2)	1.34005 (15)	0.07329 (14)	0.0276
C2	0.1938 (3)	1.3516 (2)	0.04699 (18)	0.0221
O3	0.2517 (2)	1.45464 (14)	−0.00910 (14)	0.0281
C4	0.3484 (3)	1.2387 (2)	0.08338 (17)	0.0215
C5	0.2990 (3)	1.1180 (2)	0.14000 (18)	0.0231
C6	0.4449 (3)	1.0125 (2)	0.17190 (18)	0.0233
C7	0.6447 (3)	1.0260 (2)	0.14525 (18)	0.0220
N8	0.8099 (2)	0.92608 (18)	0.17206 (15)	0.0238
N9	0.7751 (2)	0.81065 (17)	0.21222 (15)	0.0235
C10	0.9450 (3)	0.7184 (2)	0.24132 (18)	0.0243
C11	1.1313 (3)	0.7536 (2)	0.2247 (2)	0.0293
C12	1.2896 (3)	0.6624 (2)	0.2565 (2)	0.0321
C13	1.2665 (3)	0.5349 (2)	0.30679 (19)	0.0302
O14	1.4341 (2)	0.45519 (16)	0.33669 (15)	0.0364
C15	1.4290 (4)	0.3232 (2)	0.3930 (2)	0.0349
C16	1.6307 (4)	0.2701 (3)	0.4247 (2)	0.0399
C17	1.6430 (4)	0.1366 (3)	0.4911 (2)	0.0388
C18	1.7890 (4)	0.0213 (3)	0.4581 (3)	0.0455
C19	1.0850 (3)	0.4962 (2)	0.32338 (19)	0.0310
C20	0.9240 (3)	0.5897 (2)	0.28909 (19)	0.0287
C21	0.6931 (3)	1.1467 (2)	0.09065 (19)	0.0252
C22	0.5462 (3)	1.2529 (2)	0.06039 (18)	0.0238
H51	0.1631	1.1098	0.1566	0.0298*
H61	0.4112	0.9298	0.2120	0.0302*
H111	1.1483	0.8433	0.1888	0.0379*
H121	1.4168	0.6860	0.2448	0.0406*
H151	1.3110	0.3369	0.4683	0.0453*
H152	1.4146	0.2584	0.3328	0.0447*
H161	1.6418	0.3468	0.4751	0.0512*
H162	1.7478	0.2531	0.3482	0.0518*
H171	1.5325	0.1356	0.5657	0.0520*
H182	1.9017	0.0237	0.3829	0.0605*
H181	1.7859	−0.0632	0.5068	0.0604*
H191	1.0658	0.4083	0.3577	0.0394*
H201	0.8003	0.5652	0.2975	0.0369*
H211	0.8278	1.1552	0.0740	0.0331*
H221	0.5794	1.3355	0.0213	0.0322*
H2	0.1704	1.5151	−0.0423	0.0500*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0212 (7)	0.0239 (8)	0.0399 (8)	−0.0047 (6)	−0.0132 (6)	0.0029 (6)
C2	0.0228 (10)	0.0191 (10)	0.0252 (10)	−0.0034 (8)	−0.0092 (8)	−0.0018 (8)
O3	0.0270 (8)	0.0210 (8)	0.0385 (8)	−0.0048 (6)	−0.0154 (6)	0.0082 (6)
C4	0.0213 (10)	0.0195 (10)	0.0243 (9)	−0.0033 (8)	−0.0087 (8)	−0.0015 (8)
C5	0.0183 (9)	0.0230 (11)	0.0295 (10)	−0.0048 (8)	−0.0094 (8)	0.0016 (8)
C6	0.0236 (10)	0.0203 (10)	0.0279 (10)	−0.0064 (8)	−0.0098 (8)	0.0030 (8)
C7	0.0213 (10)	0.0198 (10)	0.0248 (10)	−0.0009 (8)	−0.0100 (8)	−0.0005 (8)
N8	0.0217 (8)	0.0225 (9)	0.0272 (9)	−0.0028 (7)	−0.0094 (7)	0.0016 (7)
N9	0.0207 (8)	0.0218 (9)	0.0258 (8)	−0.0003 (7)	−0.0073 (7)	−0.0008 (7)
C10	0.0235 (10)	0.0231 (11)	0.0228 (10)	0.0018 (8)	−0.0079 (8)	−0.0014 (8)
C11	0.0256 (11)	0.0273 (11)	0.0338 (11)	−0.0009 (9)	−0.0116 (9)	−0.0001 (9)
C12	0.0260 (11)	0.0317 (12)	0.0391 (12)	−0.0018 (9)	−0.0145 (9)	−0.0008 (10)
C13	0.0281 (11)	0.0311 (12)	0.0276 (10)	0.0047 (9)	−0.0119 (9)	−0.0046 (9)
O14	0.0356 (9)	0.0287 (8)	0.0461 (9)	0.0007 (7)	−0.0216 (7)	0.0028 (7)
C15	0.0410 (13)	0.0270 (12)	0.0348 (12)	−0.0002 (10)	−0.0149 (10)	−0.0006 (9)
C16	0.0456 (14)	0.0359 (14)	0.0420 (13)	−0.0055 (11)	−0.0228 (11)	0.0019 (10)
C17	0.0383 (13)	0.0374 (13)	0.0408 (13)	−0.0019 (10)	−0.0187 (10)	0.0032 (10)
C18	0.0463 (15)	0.0372 (14)	0.0563 (16)	−0.0033 (11)	−0.0264 (13)	0.0022 (12)
C19	0.0390 (12)	0.0218 (11)	0.0273 (10)	0.0000 (9)	−0.0086 (9)	0.0013 (8)
C20	0.0272 (11)	0.0270 (11)	0.0284 (11)	−0.0022 (9)	−0.0064 (8)	−0.0009 (8)
C21	0.0196 (9)	0.0265 (11)	0.0310 (10)	−0.0066 (8)	−0.0087 (8)	0.0002 (8)
C22	0.0237 (10)	0.0196 (10)	0.0294 (10)	−0.0055 (8)	−0.0101 (8)	0.0031 (8)

Geometric parameters (Å, º) top

O1—C2	1.271 (2)	C13—O14	1.367 (3)
C2—O3	1.268 (2)	C13—C19	1.395 (3)
C2—C4	1.483 (3)	O14—C15	1.426 (3)
O3—H2	0.868	C15—C16	1.529 (3)
C4—C5	1.401 (3)	C15—H151	0.993
C4—C22	1.395 (3)	C15—H152	0.996
C5—C6	1.382 (3)	C16—C17	1.479 (3)
C5—H51	0.952	C16—H161	0.998
C6—C7	1.403 (3)	C16—H162	0.997
C6—H61	0.965	C17—C18	1.312 (4)
C7—N8	1.421 (3)	C17—H171	0.974
C7—C21	1.391 (3)	C18—H182	0.989
N8—N9	1.263 (2)	C18—H181	0.978
N9—C10	1.423 (3)	C19—C20	1.408 (3)
C10—C11	1.411 (3)	C19—H191	0.959
C10—C20	1.382 (3)	C20—H201	0.947
C11—C12	1.371 (3)	C21—C22	1.382 (3)
C11—H111	0.977	C21—H211	0.945
C12—C13	1.384 (3)	C22—H221	0.959
C12—H121	0.960

O1—C2—O3	123.76 (18)	O14—C15—C16	106.04 (19)
O1—C2—C4	118.68 (17)	O14—C15—H151	109.0
O3—C2—C4	117.56 (17)	C16—C15—H151	111.8
C2—O3—H2	119.6	O14—C15—H152	108.8
C2—C4—C5	121.02 (17)	C16—C15—H152	111.3
C2—C4—C22	119.37 (17)	H151—C15—H152	109.7
C5—C4—C22	119.61 (18)	C15—C16—C17	112.4 (2)
C4—C5—C6	120.55 (18)	C15—C16—H161	106.1
C4—C5—H51	119.1	C17—C16—H161	112.0
C6—C5—H51	120.4	C15—C16—H162	111.1
C5—C6—C7	119.42 (18)	C17—C16—H162	107.0
C5—C6—H61	120.9	H161—C16—H162	108.3
C7—C6—H61	119.7	C16—C17—C18	125.6 (3)
C6—C7—N8	125.56 (18)	C16—C17—H171	116.3
C6—C7—C21	119.98 (18)	C18—C17—H171	118.0
N8—C7—C21	114.44 (17)	C17—C18—H182	117.5
C7—N8—N9	115.89 (16)	C17—C18—H181	120.8
N8—N9—C10	112.56 (16)	H182—C18—H181	121.7
N9—C10—C11	122.76 (18)	C13—C19—C20	118.9 (2)
N9—C10—C20	118.03 (18)	C13—C19—H191	122.3
C11—C10—C20	119.21 (19)	C20—C19—H191	118.8
C10—C11—C12	120.7 (2)	C19—C20—C10	120.4 (2)
C10—C11—H111	119.5	C19—C20—H201	120.6
C12—C11—H111	119.8	C10—C20—H201	118.9
C11—C12—C13	119.9 (2)	C7—C21—C22	120.46 (18)
C11—C12—H121	120.8	C7—C21—H211	119.3
C13—C12—H121	119.3	C22—C21—H211	120.3
C12—C13—O14	114.02 (19)	C4—C22—C21	119.94 (18)
C12—C13—C19	120.84 (19)	C4—C22—H221	119.3
O14—C13—C19	125.1 (2)	C21—C22—H221	120.7
C13—O14—C15	119.93 (18)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H2···O1ⁱ	0.87	1.76	2.612 (3)	166 (1)
C21—H211···O1ⁱⁱ	0.95	2.50	3.275 (3)	139 (1)

Symmetry codes: (i) −x, −y+3, −z; (ii) x+1, y, z.

Experimental details

Crystal data
Chemical formula	C₁₇H₁₆N₂O₃
M_r	296.33
Crystal system, space group	Triclinic, P1
Temperature (K)	100
a, b, c (Å)	7.0937 (7), 9.8687 (10), 11.2490 (11)
α, β, γ (°)	87.334 (8), 73.475 (8), 75.174 (8)
V (Å³)	729.54 (13)
Z	2
Radiation type	Cu Kα
µ (mm⁻¹)	0.77
Crystal size (mm)	0.26 × 0.16 × 0.04

Data collection
Diffractometer	Oxford Diffraction Gemini
Absorption correction	Multi-scan (CrysAlis RED; Oxford Diffraction, 2006)
T_min, T_max	0.85, 0.97
No. of measured, independent and observed [I > 2.0σ(I)] reflections	9940, 2783, 2298
R_int	0.024
(sin θ/λ)_max (Å⁻¹)	0.615

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.054, 0.146, 1.00
No. of reflections	2773
No. of parameters	199
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.51, −0.33

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), Superflip (Palatinus & Chapuis, 2007), CRYSTALS (Betteridge et al., 2003), Mercury (Macrae et al., 2006).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H2···O1ⁱ	0.868	1.762	2.612 (3)	165.60 (7)
C21—H211···O1ⁱⁱ	0.945	2.501	3.275 (3)	139.24 (6)

Symmetry codes: (i) −x, −y+3, −z; (ii) x+1, y, z.

Acknowledgements

This research was supported by a UMP research grant (No. RDU100338).

References

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