Crystal structure of 4-eth­oxy-N-(4-eth­oxy­phen­yl)-N-phenyl­aniline

Wu, L.-T.; Kong, M.; Wu, J.-Y.

doi:10.1107/S160053681401900X

organic compounds

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Volume 70| Part 9| September 2014| Page o1077

doi:10.1107/S160053681401900X

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Crystal structure of 4-ethoxy-N-(4-ethoxyphenyl)-N-phenylaniline

Liang-Tao Wu,^a,^b Ming Kong ^a,^b and Jie-Ying Wu ^a,^b ^*

^aDeparment of Chemistry, Anhui University, Hefei 230601, People's Republic of China, and ^bKey Laboratory of Functional Inorganic Materials Chemistry, Hefei 230601, People's Republic of China
^*Correspondence e-mail: jywu1957@163.com

Edited by D.-J. Xu, Zhejiang University (Yuquan Campus), China (Received 10 August 2014; accepted 22 August 2014; online 30 August 2014)

In the title compound, C₂₂H₂₃NO₂, the planes of the ethoxybenzene rings are oriented with respect to that of the phenyl ring at dihedral angles of 61.77 (8) and 84.77 (8)°, and they are twisted with respect to one another, with a dihedral angle of 80.37 (7)°. In the crystal, weak C—H⋯π interactions link the molecules into supramolecular chains propagating along [101].

Keywords: crystal structure; triphenylamine derivatives; supramolecular chains; C—H⋯π interactions.

CCDC reference: 1016997

1. Related literature

For applications of triphenylamine derivatives, see: Liu et al. (2012 ); Pina et al. (2013 ). For related compounds, see: Wang et al. (2011 ); Gudeika et al.(2012 ). For properties of triphenyl derivatives, see: Costa & Santos (2013 ); Metri et al. (2012 ).

2. Experimental

2.1. Crystal data

C₂₂H₂₃NO₂
M_r = 333.41
Monoclinic, P 2₁ /n
a = 7.3634 (7) Å
b = 31.908 (3) Å
c = 8.1372 (8) Å
β = 107.598 (1)°
V = 1822.4 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 298 K
0.30 × 0.20 × 0.20 mm

2.1.2. Data collection

Bruker APEXII CCD diffractometer
13155 measured reflections
3274 independent reflections
2288 reflections with I > 2σ(I)
R_int = 0.035

2.1.3. Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.106
S = 1.03
3274 reflections
228 parameters
H-atom parameters constrained
Δρ_max = 0.13 e Å⁻³
Δρ_min = −0.16 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C3–C8 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1A⋯Cg1ⁱ	0.96	2.83	3.6763 (17)	148
Symmetry code: (i) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

CCDC reference: 1016997

Crystal structure: contains datablocks I, Global. DOI: 10.1107/S160053681401900X/xu5812sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681401900X/xu5812Isup2.hkl

Supporting information file. DOI: 10.1107/S160053681401900X/xu5812Isup3.cml

checkCIF report

Comment top

Tripheylamine derivatives catch considerable interest and attention in application of OLEDs and efficient optical chemosensors due to useful properties in electrical conductivity and electroluminescence (Pina et al., 2013; Liu et al., 2012). Much effort has been made to explore the relationship between their structures and properties. The ethoxyl groups as donors in the title compound have enhanced the properties in several optical applications, its special structure also contributes to its transport properties when used to those areas (Costa & Santos, 2013 and Metri et al., 2012). In the molecule, the two ethoxybenzene rings are oriented with respect to the phenyl ring at 61.77 (8) and 84.77 (8)°, and they are twisted to each other with a dihedral angle of 80.37 (7)°. In the crystal, weak C—H···π interaction links the molecules into the supramolecular chains propagated along the [101] direction.

Related literature top

For applications of triphenylamine derivatives, see: Liu et al. (2012); Pina et al. (2013). For related compounds, see: Wang et al. (2011); Gudeika et al.(2012). For properties of triphenyl derivatives, see: Costa & Santos (2013); Metri et al. (2012).

Experimental top

A mixture of 4-iodophenol and sodium hydroxide was grinded for 0.5 h and added to 1000 ml flask, following the addition of bromoethane (750 ml) as solvent, Cs₂CO₃ (4 g) and 18-crown-6 (1 g, 3.78 mmol) as catalysts. The mixture was refluxed for 72 h, and obtained yellow oil was washed with NaOH solution (500 ml, 5%) until neutral. After extraction with dichloromethane (50 ml) for three times, the organic solution was evaporated, which yielded the intermediate as a white product (101 g, 90.5%). A 1,2-dichlorobenzene (purified) solution containing synthesized 4-ethoxy-iodobenzene (20.86 g, 75 mmol), aniline (2.38 g, 22 mmol), K₂CO₃ (17.94 g, 130 mmol), Cu powder (8.34 g, 130 mmol), 18-crown-6 (100 mg, 0.38 mmol) was stirred under N₂ for 0.5 h at room temperature, refluxed for 2 h, and continuous reaction at air. After cooling, copper was filtered out, 1,2-dichlorobenzene was evaporated, then white solid was obtained through column chromatography purification. 1H NMR: (400 MHz, (C₁D₃₎2_C1_O1), d(p.p.m.): d(p.p.m.): 7.18–7.14 (t, 2H), 7.02–7.00 (d, 4H), 6.86–6.71 (m, 7H), 4.04–3.99 (m, 4H), 1.37–1.34 (t, 6H).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound showing 30% probability displacement ellipsoids.
	Fig. 2. The weak interactions among molecules.

4-Ethoxy-N-(4-ethoxyphenyl)-N-phenylaniline top

Crystal data top

C₂₂H₂₃NO₂	F(000) = 712
M_r = 333.41	D_x = 1.215 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2593 reflections
a = 7.3634 (7) Å	θ = 2.5–21.4°
b = 31.908 (3) Å	µ = 0.08 mm⁻¹
c = 8.1372 (8) Å	T = 298 K
β = 107.598 (1)°	Block, colorless
V = 1822.4 (3) Å³	0.30 × 0.20 × 0.20 mm
Z = 4

Data collection top

Bruker APEXII CCD diffractometer	2288 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.035
Graphite monochromator	θ_max = 25.2°, θ_min = 2.6°
phi and ω scans	h = −8→8
13155 measured reflections	k = −38→36
3274 independent reflections	l = −9→9

Refinement top

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)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.106	H-atom parameters constrained
S = 1.03	w = 1/[σ²(F_o²) + (0.0539P)² + 0.0295P] where P = (F_o² + 2F_c²)/3
3274 reflections	(Δ/σ)_max = 0.001
228 parameters	Δρ_max = 0.13 e Å⁻³
0 restraints	Δρ_min = −0.16 e Å⁻³

Crystal data top

C₂₂H₂₃NO₂	V = 1822.4 (3) Å³
M_r = 333.41	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 7.3634 (7) Å	µ = 0.08 mm⁻¹
b = 31.908 (3) Å	T = 298 K
c = 8.1372 (8) Å	0.30 × 0.20 × 0.20 mm
β = 107.598 (1)°

Data collection top

Bruker APEXII CCD diffractometer	2288 reflections with I > 2σ(I)
13155 measured reflections	R_int = 0.035
3274 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	0 restraints
wR(F²) = 0.106	H-atom parameters constrained
S = 1.03	Δρ_max = 0.13 e Å⁻³
3274 reflections	Δρ_min = −0.16 e Å⁻³
228 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
N1	0.56747 (19)	0.12535 (4)	0.45337 (16)	0.0565 (4)
O1	0.53889 (15)	0.25318 (3)	−0.02262 (14)	0.0552 (3)
O2	−0.07739 (15)	0.02297 (3)	0.28521 (16)	0.0634 (3)
C1	0.5355 (2)	0.28483 (5)	−0.2863 (2)	0.0621 (5)
H1A	0.4353	0.3026	−0.2738	0.093*
H1B	0.5177	0.2798	−0.4064	0.093*
H1C	0.6563	0.2982	−0.2358	0.093*
C2	0.5312 (2)	0.24385 (5)	−0.1966 (2)	0.0543 (4)
H2A	0.4153	0.2287	−0.2540	0.065*
H2B	0.6393	0.2267	−0.1985	0.065*
C3	0.5385 (2)	0.22017 (5)	0.08506 (19)	0.0441 (4)
C4	0.5504 (2)	0.23063 (5)	0.2528 (2)	0.0510 (4)
H4	0.5517	0.2587	0.2843	0.061*
C5	0.5603 (2)	0.19973 (5)	0.3734 (2)	0.0530 (4)
H5	0.5684	0.2072	0.4859	0.064*
C6	0.5319 (2)	0.17841 (5)	0.0390 (2)	0.0513 (4)
H6	0.5204	0.1709	−0.0741	0.062*
C7	0.5424 (2)	0.14783 (5)	0.1615 (2)	0.0522 (4)
H7	0.5385	0.1198	0.1295	0.063*
C8	0.5585 (2)	0.15785 (5)	0.33024 (19)	0.0458 (4)
C9	−0.2755 (3)	−0.03507 (6)	0.1792 (3)	0.0809 (6)
H9A	−0.3214	−0.0332	0.2775	0.121*
H9B	−0.2783	−0.0638	0.1429	0.121*
H9C	−0.3551	−0.0185	0.0869	0.121*
C10	−0.0747 (2)	−0.01898 (5)	0.2265 (2)	0.0628 (5)
H10A	0.0083	−0.0362	0.3167	0.075*
H10B	−0.0282	−0.0197	0.1270	0.075*
C11	0.0897 (2)	0.04537 (5)	0.32911 (19)	0.0494 (4)
C12	0.2629 (2)	0.03055 (5)	0.3206 (2)	0.0575 (4)
H12	0.2738	0.0031	0.2863	0.069*
C13	0.4208 (2)	0.05683 (5)	0.3634 (2)	0.0591 (5)
H13	0.5368	0.0470	0.3559	0.071*
C14	0.0770 (2)	0.08574 (5)	0.3849 (2)	0.0542 (4)
H14	−0.0388	0.0957	0.3926	0.065*
C15	0.2339 (2)	0.11136 (5)	0.4291 (2)	0.0541 (4)
H15	0.2238	0.1384	0.4678	0.065*
C16	0.4072 (2)	0.09730 (5)	0.41669 (19)	0.0494 (4)
C17	0.7052 (2)	0.12510 (5)	0.61526 (19)	0.0462 (4)
C18	0.8721 (2)	0.14857 (5)	0.6470 (2)	0.0536 (4)
H18	0.8907	0.1656	0.5608	0.064*
C19	1.0098 (2)	0.14661 (5)	0.8058 (2)	0.0628 (5)
H19	1.1204	0.1624	0.8248	0.075*
C20	0.6829 (2)	0.10018 (5)	0.7488 (2)	0.0549 (4)
H20	0.5727	0.0843	0.7314	0.066*
C21	0.8226 (3)	0.09876 (6)	0.9064 (2)	0.0637 (5)
H21	0.8052	0.0819	0.9937	0.076*
C22	0.9866 (3)	0.12182 (6)	0.9362 (2)	0.0674 (5)
H22	1.0802	0.1207	1.0426	0.081*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0563 (8)	0.0573 (9)	0.0469 (8)	−0.0146 (7)	0.0020 (6)	0.0095 (7)
O1	0.0699 (7)	0.0504 (7)	0.0452 (7)	0.0056 (5)	0.0173 (5)	0.0047 (5)
O2	0.0567 (7)	0.0525 (7)	0.0794 (8)	−0.0090 (6)	0.0184 (6)	−0.0062 (6)
C1	0.0653 (11)	0.0667 (12)	0.0537 (11)	−0.0014 (9)	0.0170 (9)	0.0094 (9)
C2	0.0592 (10)	0.0608 (11)	0.0427 (9)	0.0029 (8)	0.0152 (8)	0.0027 (8)
C3	0.0410 (8)	0.0477 (9)	0.0424 (9)	0.0029 (7)	0.0108 (7)	0.0031 (8)
C4	0.0587 (10)	0.0473 (9)	0.0475 (10)	0.0038 (7)	0.0170 (8)	−0.0043 (8)
C5	0.0613 (10)	0.0586 (11)	0.0406 (9)	−0.0003 (8)	0.0177 (8)	−0.0034 (8)
C6	0.0579 (10)	0.0536 (10)	0.0392 (9)	−0.0026 (8)	0.0100 (7)	−0.0023 (8)
C7	0.0600 (10)	0.0445 (9)	0.0479 (10)	−0.0066 (7)	0.0101 (8)	−0.0050 (8)
C8	0.0428 (9)	0.0493 (10)	0.0418 (9)	−0.0060 (7)	0.0073 (7)	0.0021 (7)
C9	0.0746 (13)	0.0733 (13)	0.0890 (15)	−0.0234 (10)	0.0162 (11)	−0.0096 (11)
C10	0.0723 (12)	0.0518 (11)	0.0646 (12)	−0.0113 (8)	0.0214 (9)	−0.0050 (9)
C11	0.0503 (10)	0.0492 (10)	0.0461 (9)	−0.0065 (7)	0.0108 (7)	0.0033 (7)
C12	0.0615 (11)	0.0440 (9)	0.0662 (12)	−0.0021 (8)	0.0179 (9)	−0.0032 (8)
C13	0.0532 (10)	0.0563 (11)	0.0672 (12)	−0.0002 (8)	0.0175 (9)	−0.0009 (9)
C14	0.0544 (10)	0.0496 (10)	0.0591 (11)	0.0011 (8)	0.0180 (8)	0.0012 (8)
C15	0.0636 (11)	0.0439 (9)	0.0531 (10)	−0.0035 (8)	0.0152 (8)	−0.0006 (7)
C16	0.0510 (9)	0.0508 (10)	0.0414 (9)	−0.0072 (8)	0.0062 (7)	0.0045 (7)
C17	0.0504 (9)	0.0446 (9)	0.0411 (9)	0.0015 (7)	0.0100 (7)	−0.0019 (7)
C18	0.0553 (10)	0.0524 (10)	0.0498 (10)	−0.0034 (8)	0.0107 (8)	−0.0025 (8)
C19	0.0552 (10)	0.0608 (11)	0.0617 (12)	−0.0038 (8)	0.0018 (9)	−0.0080 (9)
C20	0.0575 (10)	0.0569 (10)	0.0497 (10)	−0.0005 (8)	0.0153 (8)	0.0023 (8)
C21	0.0772 (13)	0.0652 (12)	0.0457 (10)	0.0101 (10)	0.0139 (9)	0.0043 (9)
C22	0.0718 (12)	0.0681 (12)	0.0485 (11)	0.0082 (10)	−0.0027 (9)	−0.0077 (9)

Geometric parameters (Å, º) top

N1—C17	1.3985 (19)	C9—H9B	0.9600
N1—C8	1.4296 (18)	C9—H9C	0.9600
N1—C16	1.4384 (18)	C10—H10A	0.9700
O1—C3	1.3705 (17)	C10—H10B	0.9700
O1—C2	1.4312 (18)	C11—C14	1.378 (2)
O2—C11	1.3736 (17)	C11—C12	1.382 (2)
O2—C10	1.4237 (19)	C12—C13	1.389 (2)
C1—C2	1.502 (2)	C12—H12	0.9300
C1—H1A	0.9600	C13—C16	1.376 (2)
C1—H1B	0.9600	C13—H13	0.9300
C1—H1C	0.9600	C14—C15	1.372 (2)
C2—H2A	0.9700	C14—H14	0.9300
C2—H2B	0.9700	C15—C16	1.385 (2)
C3—C6	1.381 (2)	C15—H15	0.9300
C3—C4	1.382 (2)	C17—C18	1.395 (2)
C4—C5	1.378 (2)	C17—C20	1.395 (2)
C4—H4	0.9300	C18—C19	1.382 (2)
C5—C8	1.381 (2)	C18—H18	0.9300
C5—H5	0.9300	C19—C22	1.375 (2)
C6—C7	1.380 (2)	C19—H19	0.9300
C6—H6	0.9300	C20—C21	1.381 (2)
C7—C8	1.379 (2)	C20—H20	0.9300
C7—H7	0.9300	C21—C22	1.372 (2)
C9—C10	1.501 (2)	C21—H21	0.9300
C9—H9A	0.9600	C22—H22	0.9300

C17—N1—C8	122.07 (12)	O2—C10—H10A	110.3
C17—N1—C16	120.50 (12)	C9—C10—H10A	110.3
C8—N1—C16	116.40 (12)	O2—C10—H10B	110.3
C3—O1—C2	117.76 (12)	C9—C10—H10B	110.3
C11—O2—C10	118.31 (12)	H10A—C10—H10B	108.5
C2—C1—H1A	109.5	O2—C11—C14	115.30 (14)
C2—C1—H1B	109.5	O2—C11—C12	125.23 (14)
H1A—C1—H1B	109.5	C14—C11—C12	119.48 (14)
C2—C1—H1C	109.5	C11—C12—C13	119.72 (15)
H1A—C1—H1C	109.5	C11—C12—H12	120.1
H1B—C1—H1C	109.5	C13—C12—H12	120.1
O1—C2—C1	107.40 (13)	C16—C13—C12	120.71 (15)
O1—C2—H2A	110.2	C16—C13—H13	119.6
C1—C2—H2A	110.2	C12—C13—H13	119.6
O1—C2—H2B	110.2	C15—C14—C11	120.51 (15)
C1—C2—H2B	110.2	C15—C14—H14	119.7
H2A—C2—H2B	108.5	C11—C14—H14	119.7
O1—C3—C6	125.08 (13)	C14—C15—C16	120.63 (15)
O1—C3—C4	115.74 (13)	C14—C15—H15	119.7
C6—C3—C4	119.16 (14)	C16—C15—H15	119.7
C5—C4—C3	120.33 (15)	C13—C16—C15	118.91 (14)
C5—C4—H4	119.8	C13—C16—N1	121.09 (15)
C3—C4—H4	119.8	C15—C16—N1	119.96 (14)
C4—C5—C8	121.12 (14)	C18—C17—C20	117.78 (14)
C4—C5—H5	119.4	C18—C17—N1	121.23 (14)
C8—C5—H5	119.4	C20—C17—N1	120.95 (14)
C7—C6—C3	119.78 (14)	C19—C18—C17	120.33 (16)
C7—C6—H6	120.1	C19—C18—H18	119.8
C3—C6—H6	120.1	C17—C18—H18	119.8
C8—C7—C6	121.61 (14)	C22—C19—C18	121.37 (17)
C8—C7—H7	119.2	C22—C19—H19	119.3
C6—C7—H7	119.2	C18—C19—H19	119.3
C7—C8—C5	117.96 (14)	C21—C20—C17	120.81 (16)
C7—C8—N1	120.09 (14)	C21—C20—H20	119.6
C5—C8—N1	121.92 (14)	C17—C20—H20	119.6
C10—C9—H9A	109.5	C22—C21—C20	121.00 (17)
C10—C9—H9B	109.5	C22—C21—H21	119.5
H9A—C9—H9B	109.5	C20—C21—H21	119.5
C10—C9—H9C	109.5	C21—C22—C19	118.70 (16)
H9A—C9—H9C	109.5	C21—C22—H22	120.6
H9B—C9—H9C	109.5	C19—C22—H22	120.6
O2—C10—C9	107.15 (14)

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C3–C8 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1A···Cg1ⁱ	0.96	2.83	3.6763 (17)	148

Symmetry code: (i) x−1/2, −y+1/2, z−1/2.

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C3–C8 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1A···Cg1ⁱ	0.96	2.83	3.6763 (17)	148

Symmetry code: (i) x−1/2, −y+1/2, z−1/2.

Acknowledgements

The work was supported by the National Natural Science Foundation of China (grant Nos. 21271004 and 51372003) and the Natural Science Foundation of Anhui Province, China (grant No. 1208085MB22).

References

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Volume 70| Part 9| September 2014| Page o1077

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