1-Eth­oxy-2-meth­oxy-4-[2-(4-nitro­phen­yl)ethen­yl]benzene

Dinakaran, P.M.; Kalainathan, S.; Srinivasan, T.; Velmurugan, D.

doi:10.1107/S1600536812034320

organic compounds

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ISSN: 2056-9890

Volume 68| Part 9| September 2012| Page o2774

doi:10.1107/S1600536812034320

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1-Ethoxy-2-methoxy-4-[2-(4-nitrophenyl)ethenyl]benzene

Paul M. Dinakaran,^a S. Kalainathan,^a ^* T. Srinivasan ^b and D. Velmurugan ^b

^aCrystal Research Centre, School of Advanced Sciences, VIT University, Vellore 632 014, Tamil Nadu, India, and ^bCentre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India
^*Correspondence e-mail: Kalainathan@yahoo.com

(Received 25 July 2012; accepted 1 August 2012; online 25 August 2012)

In the title molecule, C₁₇H₁₇NO₄, the dihedral angle between the two aromatic rings is 42.47 (7)°. The nitro group is twisted by 7.44 (11)° out of the plane of the ring to which it is attached. The methoxy and ethoxy group O atoms deviate significantly from the phenyl ring [by 0.0108 (11) and 0.0449 (11) Å, respectively]. The crystal structure is stabilized by C—H⋯π interactions.

Related literature

For the synthesis of the title compound, see: Tam et al. (1989 ). For hybridization, see: Beddoes et al. (1986 )

Experimental

Crystal data

C₁₇H₁₇NO₄
M_r = 299.32
Monoclinic, P 2₁ /n
a = 8.5209 (4) Å
b = 7.5959 (4) Å
c = 23.7877 (13) Å
β = 99.611 (3)°
V = 1518.02 (14) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 293 K
0.20 × 0.20 × 0.20 mm

Data collection

Bruker SMART APEXII area-detector diffractometer
14265 measured reflections
3789 independent reflections
2831 reflections with I > 2σ(I)
R_int = 0.031

Refinement

R[F² > 2σ(F²)] = 0.045
wR(F²) = 0.138
S = 1.04
3789 reflections
202 parameters
H-atom parameters constrained
Δρ_max = 0.22 e Å⁻³
Δρ_min = −0.19 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 is the centroid of the C9–C14 benzene ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C17—H17A⋯Cg2	0.97	2.96	3.281 (2)	145

Data collection: APEX2 (Bruker, 2008 ); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812034320/bt5986sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812034320/bt5986Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812034320/bt5986Isup3.cml

checkCIF report

Comment top

The dihedral angle between nitro substituted phenyl ring (C1-C6) & oxygen substituted benzene ring (C9-C14) is 42.47 (7)°. The sum of bond angles around N1 (359.59°) is in accordance with sp₂ hybridization (Beddoes et al., 1986). The methoxy and ethoxy group O3 and O4 atoms are significantly deviated from the phenyl ring (C9–C13) with the values of -0.0108 (11) Å and -0.0449 (11) Å, respectively.

A weak intermolecular C—H···π interaction involving the C17–H17A group and the C9–C14 benzene ring (centroid Cg2) of the molecule at (2-x,-y,-z) is observed [H17A···Cg2 = 2.96 Å, C17···Cg2 = 3.781 (2) Å and C17-H17A···Cg2 = 145°].

Related literature top

For the synthesis of the title compound, see: Tam et al. (1989). For hybridization, see: Beddoes et al. (1986).

Experimental top

4-Ethoxy 3-Methoxy 4-Nitrostilbene (4E3MONS) is a derivative material of stilebene.The material (4E3MONS) was synthesized by Witting reaction method. The material was prepared from the 4-ethoxy 3-methoxy benzaldehyde and diethyl p-nitrobenzyl phosphonate in the presence of sodium ethoxide catalyst. The steps involved during the chemical reactions are as follows: the calculated amount of diethyl p-nitrobenzyl phosphonate (0.01 mol %, 2.2304ml) and 4-ethoxy 3-methoxy benzaldehyde (0.01 mol, 1.802 ml %) were added in the ethanol solution (35 ml). After the reaction process, the sodium ethoxide,which plays a role of catalyst, was added immediately the colour of the solution became red. Then the mixture was stirred for 12 hrs at ice cold temperature in ultracryostat which has stirrer rotation facility. After the stirring process completed, the orange colour 4E3MONS material was collected from the mixture by removing the ethanol (Tam et al., 1989). Then the 4E3MONS was purified by a successive recrystallization process.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

Fig. 1. The molecular structure of the title compound, showing displacement ellipsoids drawn at the 30% probability level. H atoms are presented as small spheres of arbitrary radius.

Fig. 2. A view of the C—H···N and C—H···O hydrogen bonds (dotted lines) in the crystal structure of the title compound. [Symmetry codes: (i) - x + 1, - y -1, - z; (ii) - x +1/2, y - 1/2, - z + 1/2.]

1-Ethoxy-2-methoxy-4-[2-(4-nitrophenyl)ethenyl]benzene top

Crystal data top

C₁₇H₁₇NO₄	F(000) = 632
M_r = 299.32	D_x = 1.310 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 3789 reflections
a = 8.5209 (4) Å	θ = 1.7–28.5°
b = 7.5959 (4) Å	µ = 0.09 mm⁻¹
c = 23.7877 (13) Å	T = 293 K
β = 99.611 (3)°	Block, colourless
V = 1518.02 (14) Å³	0.20 × 0.20 × 0.20 mm
Z = 4

Data collection top

Bruker SMART APEXII area-detector diffractometer	2831 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.031
Graphite monochromator	θ_max = 28.5°, θ_min = 1.7°
ω and ϕ scans	h = −11→11
14265 measured reflections	k = −9→9
3789 independent reflections	l = −31→30

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.045	H-atom parameters constrained
wR(F²) = 0.138	w = 1/[σ²(F_o²) + (0.0628P)² + 0.2742P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max = 0.001
3789 reflections	Δρ_max = 0.22 e Å⁻³
202 parameters	Δρ_min = −0.19 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.121 (6)

Crystal data top

C₁₇H₁₇NO₄	V = 1518.02 (14) Å³
M_r = 299.32	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 8.5209 (4) Å	µ = 0.09 mm⁻¹
b = 7.5959 (4) Å	T = 293 K
c = 23.7877 (13) Å	0.20 × 0.20 × 0.20 mm
β = 99.611 (3)°

Data collection top

Bruker SMART APEXII area-detector diffractometer	2831 reflections with I > 2σ(I)
14265 measured reflections	R_int = 0.031
3789 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.045	0 restraints
wR(F²) = 0.138	H-atom parameters constrained
S = 1.04	Δρ_max = 0.22 e Å⁻³
3789 reflections	Δρ_min = −0.19 e Å⁻³
202 parameters

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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

	x	y	z	U_iso*/U_eq
O4	1.09886 (11)	0.13016 (14)	0.06184 (5)	0.0622 (3)
O3	0.89997 (12)	0.38803 (13)	0.04273 (5)	0.0619 (3)
C9	0.70663 (15)	0.13692 (18)	0.14525 (6)	0.0488 (3)
C13	0.86351 (14)	0.26322 (17)	0.07949 (5)	0.0468 (3)
C4	0.42645 (15)	0.09455 (17)	0.25675 (6)	0.0469 (3)
N1	0.04474 (16)	0.11093 (17)	0.34984 (6)	0.0644 (4)
C1	0.17789 (16)	0.10582 (17)	0.31788 (6)	0.0508 (3)
C8	0.57030 (15)	0.15205 (19)	0.17555 (6)	0.0512 (3)
H8	0.4829	0.2161	0.1578	0.061*
C14	0.73211 (14)	0.26748 (18)	0.10663 (5)	0.0478 (3)
H14	0.6594	0.3592	0.0990	0.057*
C6	0.14936 (16)	0.14921 (19)	0.26099 (6)	0.0545 (3)
H6	0.0478	0.1812	0.2432	0.065*
C10	0.81278 (17)	−0.0027 (2)	0.15429 (7)	0.0584 (4)
H10	0.7962	−0.0925	0.1792	0.070*
C5	0.27400 (16)	0.14451 (19)	0.23074 (6)	0.0529 (3)
H5	0.2561	0.1752	0.1924	0.063*
C12	0.97140 (15)	0.12289 (18)	0.08991 (6)	0.0496 (3)
C11	0.94367 (16)	−0.0096 (2)	0.12641 (7)	0.0583 (4)
H11	1.0131	−0.1048	0.1325	0.070*
C7	0.56122 (15)	0.08254 (19)	0.22582 (6)	0.0538 (3)
H7	0.6494	0.0195	0.2434	0.065*
O1	−0.08925 (15)	0.13496 (19)	0.32390 (7)	0.0886 (4)
C3	0.44945 (16)	0.0507 (2)	0.31410 (6)	0.0556 (3)
H3	0.5502	0.0165	0.3321	0.067*
C16	1.20153 (17)	−0.0197 (2)	0.06557 (7)	0.0630 (4)
H16A	1.1425	−0.1227	0.0499	0.076*
H16B	1.2462	−0.0435	0.1051	0.076*
C2	0.32634 (17)	0.0564 (2)	0.34522 (6)	0.0579 (4)
H2	0.3435	0.0274	0.3837	0.070*
C17	1.33198 (18)	0.0214 (3)	0.03219 (8)	0.0733 (5)
H17A	1.2867	0.0416	−0.0070	0.110*
H17B	1.4046	−0.0759	0.0347	0.110*
H17C	1.3880	0.1250	0.0476	0.110*
C15	0.7940 (2)	0.5327 (2)	0.03028 (7)	0.0693 (4)
H15A	0.6912	0.4905	0.0128	0.104*
H15B	0.8345	0.6119	0.0047	0.104*
H15C	0.7848	0.5935	0.0650	0.104*
O2	0.07343 (17)	0.0848 (2)	0.40088 (6)	0.1057 (6)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O4	0.0506 (5)	0.0632 (6)	0.0811 (7)	0.0073 (4)	0.0349 (5)	0.0034 (5)
O3	0.0615 (6)	0.0597 (6)	0.0727 (7)	0.0083 (5)	0.0347 (5)	0.0121 (5)
C9	0.0411 (6)	0.0529 (7)	0.0553 (7)	−0.0035 (5)	0.0169 (5)	−0.0032 (6)
C13	0.0448 (6)	0.0474 (7)	0.0511 (7)	−0.0029 (5)	0.0167 (5)	−0.0033 (5)
C4	0.0443 (6)	0.0456 (7)	0.0534 (7)	−0.0031 (5)	0.0155 (5)	0.0005 (5)
N1	0.0640 (8)	0.0611 (8)	0.0759 (9)	−0.0142 (6)	0.0349 (7)	−0.0055 (6)
C1	0.0525 (7)	0.0461 (7)	0.0592 (8)	−0.0081 (5)	0.0247 (6)	−0.0038 (6)
C8	0.0429 (6)	0.0531 (7)	0.0611 (8)	0.0003 (5)	0.0190 (6)	0.0011 (6)
C14	0.0426 (6)	0.0496 (7)	0.0540 (7)	0.0011 (5)	0.0159 (5)	−0.0040 (6)
C6	0.0465 (7)	0.0549 (8)	0.0647 (9)	0.0044 (6)	0.0169 (6)	0.0081 (6)
C10	0.0531 (7)	0.0541 (8)	0.0730 (10)	0.0013 (6)	0.0252 (7)	0.0095 (7)
C5	0.0496 (7)	0.0595 (8)	0.0522 (7)	0.0033 (6)	0.0157 (6)	0.0090 (6)
C12	0.0411 (6)	0.0530 (7)	0.0586 (8)	−0.0017 (5)	0.0195 (5)	−0.0055 (6)
C11	0.0496 (7)	0.0528 (8)	0.0770 (10)	0.0071 (6)	0.0234 (7)	0.0046 (7)
C7	0.0420 (6)	0.0619 (8)	0.0594 (8)	0.0016 (6)	0.0145 (6)	0.0035 (7)
O1	0.0603 (7)	0.1011 (10)	0.1138 (10)	0.0131 (7)	0.0422 (7)	0.0163 (8)
C3	0.0479 (7)	0.0656 (9)	0.0531 (8)	−0.0037 (6)	0.0082 (6)	0.0046 (7)
C16	0.0515 (7)	0.0690 (10)	0.0734 (10)	0.0109 (7)	0.0250 (7)	−0.0059 (8)
C2	0.0604 (8)	0.0668 (9)	0.0485 (7)	−0.0102 (7)	0.0143 (6)	0.0016 (6)
C17	0.0513 (8)	0.0977 (13)	0.0768 (11)	0.0075 (8)	0.0276 (7)	−0.0102 (9)
C15	0.0742 (10)	0.0692 (10)	0.0708 (10)	0.0166 (8)	0.0301 (8)	0.0191 (8)
O2	0.0873 (9)	0.1721 (16)	0.0668 (8)	−0.0343 (10)	0.0395 (7)	−0.0100 (9)

Geometric parameters (Å, º) top

O4—C12	1.3678 (14)	C6—C5	1.3791 (18)
O4—C16	1.4296 (17)	C6—H6	0.9300
O3—C13	1.3605 (16)	C10—C11	1.3905 (18)
O3—C15	1.4218 (18)	C10—H10	0.9300
C9—C10	1.3871 (19)	C5—H5	0.9300
C9—C14	1.3933 (19)	C12—C11	1.375 (2)
C9—C8	1.4702 (17)	C11—H11	0.9300
C13—C14	1.3831 (16)	C7—H7	0.9300
C13—C12	1.4024 (18)	C3—C2	1.3818 (19)
C4—C3	1.386 (2)	C3—H3	0.9300
C4—C5	1.3950 (18)	C16—C17	1.503 (2)
C4—C7	1.4664 (18)	C16—H16A	0.9700
N1—O2	1.2141 (19)	C16—H16B	0.9700
N1—O1	1.2175 (19)	C2—H2	0.9300
N1—C1	1.4678 (17)	C17—H17A	0.9600
C1—C2	1.375 (2)	C17—H17B	0.9600
C1—C6	1.375 (2)	C17—H17C	0.9600
C8—C7	1.321 (2)	C15—H15A	0.9600
C8—H8	0.9300	C15—H15B	0.9600
C14—H14	0.9300	C15—H15C	0.9600

C12—O4—C16	117.72 (11)	O4—C12—C13	115.69 (12)
C13—O3—C15	117.87 (10)	C11—C12—C13	119.43 (11)
C10—C9—C14	118.49 (12)	C12—C11—C10	120.62 (13)
C10—C9—C8	122.14 (12)	C12—C11—H11	119.7
C14—C9—C8	119.37 (12)	C10—C11—H11	119.7
O3—C13—C14	124.98 (12)	C8—C7—C4	126.75 (13)
O3—C13—C12	115.47 (11)	C8—C7—H7	116.6
C14—C13—C12	119.54 (12)	C4—C7—H7	116.6
C3—C4—C5	118.04 (12)	C2—C3—C4	121.63 (13)
C3—C4—C7	119.01 (12)	C2—C3—H3	119.2
C5—C4—C7	122.94 (12)	C4—C3—H3	119.2
O2—N1—O1	123.13 (14)	O4—C16—C17	107.48 (14)
O2—N1—C1	118.00 (14)	O4—C16—H16A	110.2
O1—N1—C1	118.82 (14)	C17—C16—H16A	110.2
C2—C1—C6	121.92 (12)	O4—C16—H16B	110.2
C2—C1—N1	119.48 (13)	C17—C16—H16B	110.2
C6—C1—N1	118.59 (13)	H16A—C16—H16B	108.5
C7—C8—C9	125.65 (13)	C1—C2—C3	118.44 (13)
C7—C8—H8	117.2	C1—C2—H2	120.8
C9—C8—H8	117.2	C3—C2—H2	120.8
C13—C14—C9	121.24 (12)	C16—C17—H17A	109.5
C13—C14—H14	119.4	C16—C17—H17B	109.5
C9—C14—H14	119.4	H17A—C17—H17B	109.5
C1—C6—C5	118.84 (13)	C16—C17—H17C	109.5
C1—C6—H6	120.6	H17A—C17—H17C	109.5
C5—C6—H6	120.6	H17B—C17—H17C	109.5
C9—C10—C11	120.61 (13)	O3—C15—H15A	109.5
C9—C10—H10	119.7	O3—C15—H15B	109.5
C11—C10—H10	119.7	H15A—C15—H15B	109.5
C6—C5—C4	121.13 (13)	O3—C15—H15C	109.5
C6—C5—H5	119.4	H15A—C15—H15C	109.5
C4—C5—H5	119.4	H15B—C15—H15C	109.5
O4—C12—C11	124.88 (12)

C15—O3—C13—C14	−1.2 (2)	C16—O4—C12—C11	7.3 (2)
C15—O3—C13—C12	179.55 (13)	C16—O4—C12—C13	−172.56 (13)
O2—N1—C1—C2	5.9 (2)	O3—C13—C12—O4	0.07 (18)
O1—N1—C1—C2	−171.61 (15)	C14—C13—C12—O4	−179.27 (12)
O2—N1—C1—C6	−174.80 (15)	O3—C13—C12—C11	−179.80 (13)
O1—N1—C1—C6	7.7 (2)	C14—C13—C12—C11	0.9 (2)
C10—C9—C8—C7	25.6 (2)	O4—C12—C11—C10	178.12 (14)
C14—C9—C8—C7	−153.64 (15)	C13—C12—C11—C10	−2.0 (2)
O3—C13—C14—C9	−177.74 (13)	C9—C10—C11—C12	0.8 (2)
C12—C13—C14—C9	1.5 (2)	C9—C8—C7—C4	−179.53 (13)
C10—C9—C14—C13	−2.7 (2)	C3—C4—C7—C8	−164.96 (15)
C8—C9—C14—C13	176.55 (12)	C5—C4—C7—C8	16.6 (2)
C2—C1—C6—C5	−0.7 (2)	C5—C4—C3—C2	−0.3 (2)
N1—C1—C6—C5	−179.95 (13)	C7—C4—C3—C2	−178.83 (13)
C14—C9—C10—C11	1.5 (2)	C12—O4—C16—C17	−179.27 (13)
C8—C9—C10—C11	−177.69 (14)	C6—C1—C2—C3	0.0 (2)
C1—C6—C5—C4	0.9 (2)	N1—C1—C2—C3	179.29 (13)
C3—C4—C5—C6	−0.4 (2)	C4—C3—C2—C1	0.5 (2)
C7—C4—C5—C6	178.09 (13)

Hydrogen-bond geometry (Å, º) top

Cg2 is the centroid of the C9–C14 benzene ring.

D—H···A	D—H	H···A	D···A	D—H···A
C17—H17A···Cg2	0.97	2.96	3.281 (2)	145

Experimental details

Crystal data
Chemical formula	C₁₇H₁₇NO₄
M_r	299.32
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	293
a, b, c (Å)	8.5209 (4), 7.5959 (4), 23.7877 (13)
β (°)	99.611 (3)
V (Å³)	1518.02 (14)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.20 × 0.20 × 0.20

Data collection
Diffractometer	Bruker SMART APEXII area-detector diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	14265, 3789, 2831
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.671

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.045, 0.138, 1.04
No. of reflections	3789
No. of parameters	202
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.19

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

Cg2 is the centroid of the C9–C14 benzene ring.

D—H···A	D—H	H···A	D···A	D—H···A
C17—H17A···Cg2	0.97	2.96	3.281 (2)	145

Acknowledgements

TS and DV thank the TBI X-ray facility, CAS in Crystallography and Biophysics, University of Madras, India, for data collection and TS thanks DST for the Inspire fellowship. PMD and SK thank SERC–DST for providing financial support and VIT University management for their constant encouragement.

References

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Volume 68| Part 9| September 2012| Page o2774

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