trans-3,3',4,5'-Tetra-meth-oxy-stilbene.

The title compound, C(18)H(20)O(4), was synthesized by a Wittig-Horner reaction of diethyl 3,4-dimeth-oxy-benzyl-phosphate and 3,5-dimeth-oxy-benzaldehyde. In the crystal, the dihedral angle between the two aromatic rings is 2.47 (12)°. All the meth-oxy groups are almost coplanar with the aromatic ring to which they are attached [C-C-O-C torsion angles = -2.8 (3), -5.2 (4), -176.3 (2) and -178.0 (2)°].

Related literature

For the bioactivity of stilbene-based compounds, see: Nam et al. (2001 ▶); Belleri et al. (2005 ▶); Gosslau et al. (2005 ▶); Sale et al. (2004 ▶). For reference structural data, see: Piao et al. (2002 ▶); Shibutani et al. (2004 ▶).

Experimental

Crystal data

C18H20O4

M = 300.34

Orthorhombic,

a = 5.2431 (2) Å

b = 11.9840 (7) Å

c = 25.6315 (11) Å

V = 1610.51 (14) Å3

Z = 4

Cu Kα radiation

μ = 0.71 mm−1

T = 293 K

0.42 × 0.11 × 0.07 mm

Data collection

Agilent Xcalibur Sapphire3 Gemini ultra diffractometer

Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010 ▶) T min = 0.781, T max = 1.000

2952 measured reflections

2032 independent reflections

1791 reflections with I > 2σ(I)

R int = 0.020

Refinement

R[F 2 > 2σ(F 2)] = 0.039

wR(F 2) = 0.095

S = 1.13

2032 reflections

203 parameters

H-atom parameters constrained

Δρmax = 0.13 e Å−3

Δρmin = −0.15 e Å−3

Data collection: CrysAlis PRO (Agilent, 2010 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: OLEX2 (Dolomanov et al., 2009 ▶); software used to prepare material for publication: OLEX2.

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S160053681102575X/ff2018sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S160053681102575X/ff2018Isup2.hkl

Supplementary material file. DOI: 10.1107/S160053681102575X/ff2018Isup3.cml

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

C18H20O4	Dx = 1.239 Mg m−3
Mr = 300.34	Cu Kα radiation, λ = 1.5418 Å
Orthorhombic, P212121	Cell parameters from 1273 reflections
a = 5.2431 (2) Å	θ = 3.5–62.6°
b = 11.9840 (7) Å	µ = 0.71 mm−1
c = 25.6315 (11) Å	T = 293 K
V = 1610.51 (14) Å3	Needle, light colourless
Z = 4	0.42 × 0.11 × 0.07 mm
F(000) = 640

Agilent Xcalibur Sapphire3 Gemini ultra diffractometer	2032 independent reflections
Radiation source: Enhance Ultra (Cu) X-ray Source	1791 reflections with I > 2σ(I)
mirror	Rint = 0.020
Detector resolution: 16.0288 pixels mm-1	θmax = 62.7°, θmin = 3.5°
ω scans	h = −3→5
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010)	k = −13→11
Tmin = 0.781, Tmax = 1.000	l = −17→29
2952 measured reflections

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)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.095	H-atom parameters constrained
S = 1.13	w = 1/[σ2(Fo2) + (0.0429P)2] where P = (Fo2 + 2Fc2)/3
2032 reflections	(Δ/σ)max = 0.005
203 parameters	Δρmax = 0.13 e Å−3
0 restraints	Δρmin = −0.15 e Å−3

Experimental. CrysAlisPro, Agilent Technologies (2010). Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

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.

	x	y	z	Uiso*/Ueq
O2	0.2225 (4)	0.53444 (16)	0.41963 (6)	0.0686 (5)
O3	0.4129 (3)	0.05952 (15)	0.78118 (6)	0.0590 (5)
O4	−0.2862 (3)	0.29517 (15)	0.82410 (6)	0.0604 (5)
O1	−0.1078 (4)	0.59508 (15)	0.48866 (6)	0.0628 (5)
C4	0.3989 (5)	0.3431 (2)	0.52589 (10)	0.0555 (6)
H4	0.5169	0.2873	0.5332	0.067*
C5	0.2240 (5)	0.3738 (2)	0.56362 (8)	0.0481 (6)
C7	0.2275 (5)	0.3164 (2)	0.61401 (9)	0.0533 (6)
H7	0.3621	0.2674	0.6196	0.064*
C8	0.0604 (5)	0.3265 (2)	0.65256 (9)	0.0519 (6)
H8	−0.0766	0.3742	0.6467	0.062*
C10	0.2460 (5)	0.1874 (2)	0.71574 (9)	0.0475 (6)
H10	0.3631	0.1637	0.6908	0.057*
C18	0.5886 (5)	0.0176 (2)	0.74345 (11)	0.0649 (7)
H18A	0.4962	−0.0122	0.7143	0.097*
H18B	0.6904	−0.0402	0.7589	0.097*
H18C	0.6974	0.0770	0.7318	0.097*
C14	−0.1071 (5)	0.3027 (2)	0.74094 (8)	0.0467 (5)
H14	−0.2284	0.3567	0.7329	0.056*
C17	−0.3087 (6)	0.2439 (3)	0.87367 (9)	0.0762 (9)
H17A	−0.3381	0.1654	0.8693	0.114*
H17B	−0.4491	0.2764	0.8923	0.114*
H17C	−0.1542	0.2551	0.8931	0.114*
C13	−0.1035 (5)	0.25517 (19)	0.79054 (8)	0.0467 (6)
C12	0.0729 (5)	0.17448 (19)	0.80283 (9)	0.0476 (6)
H12	0.0755	0.1430	0.8360	0.057*
C2	0.2307 (5)	0.4775 (2)	0.46577 (8)	0.0505 (6)
C3	0.4011 (5)	0.3941 (2)	0.47741 (9)	0.0562 (6)
H3	0.5193	0.3717	0.4525	0.067*
C6	0.0495 (5)	0.4586 (2)	0.55153 (8)	0.0489 (6)
H6	−0.0698	0.4803	0.5764	0.059*
C1	0.0516 (5)	0.51025 (19)	0.50366 (9)	0.0470 (6)
C11	0.2464 (4)	0.14063 (19)	0.76539 (9)	0.0458 (5)
C16	−0.2818 (5)	0.6360 (2)	0.52633 (11)	0.0659 (7)
H16A	−0.3802	0.6956	0.5115	0.099*
H16B	−0.1893	0.6632	0.5560	0.099*
H16C	−0.3939	0.5769	0.5370	0.099*
C15	0.4072 (7)	0.5055 (3)	0.38112 (10)	0.0841 (10)
H15A	0.3910	0.5548	0.3518	0.126*
H15B	0.3797	0.4300	0.3700	0.126*
H15C	0.5751	0.5124	0.3957	0.126*
C9	0.0682 (5)	0.27030 (18)	0.70361 (8)	0.0449 (5)

	U11	U22	U33	U12	U13	U23
O2	0.0870 (13)	0.0752 (13)	0.0434 (9)	0.0076 (12)	0.0101 (9)	0.0135 (9)
O3	0.0593 (10)	0.0559 (10)	0.0617 (10)	0.0104 (10)	−0.0042 (9)	0.0068 (9)
O4	0.0648 (10)	0.0701 (11)	0.0464 (9)	0.0110 (10)	0.0090 (8)	0.0026 (9)
O1	0.0669 (11)	0.0672 (11)	0.0542 (10)	0.0155 (11)	0.0045 (9)	0.0121 (9)
C4	0.0592 (15)	0.0524 (14)	0.0548 (14)	0.0072 (14)	0.0026 (14)	0.0046 (13)
C5	0.0507 (13)	0.0497 (14)	0.0439 (12)	0.0002 (13)	0.0001 (11)	0.0043 (11)
C7	0.0600 (15)	0.0520 (15)	0.0478 (13)	0.0057 (13)	−0.0002 (12)	0.0050 (12)
C8	0.0566 (13)	0.0502 (14)	0.0490 (13)	0.0045 (13)	0.0000 (12)	0.0045 (12)
C10	0.0483 (13)	0.0482 (13)	0.0459 (13)	−0.0053 (12)	0.0028 (11)	−0.0017 (11)
C18	0.0560 (14)	0.0570 (16)	0.0816 (18)	0.0096 (15)	0.0003 (15)	−0.0009 (15)
C14	0.0504 (13)	0.0438 (12)	0.0459 (12)	0.0006 (12)	−0.0013 (11)	0.0014 (11)
C17	0.090 (2)	0.093 (2)	0.0449 (14)	0.0152 (19)	0.0171 (14)	0.0093 (15)
C13	0.0501 (13)	0.0501 (14)	0.0399 (12)	−0.0048 (12)	−0.0010 (11)	−0.0025 (11)
C12	0.0527 (13)	0.0527 (14)	0.0374 (11)	−0.0015 (13)	−0.0032 (11)	0.0042 (11)
C2	0.0609 (15)	0.0519 (14)	0.0388 (11)	−0.0039 (14)	0.0018 (11)	0.0050 (11)
C3	0.0622 (14)	0.0581 (15)	0.0484 (13)	0.0069 (14)	0.0117 (13)	0.0010 (13)
C6	0.0515 (13)	0.0535 (14)	0.0417 (12)	−0.0013 (12)	0.0044 (11)	0.0008 (12)
C1	0.0506 (14)	0.0462 (13)	0.0443 (12)	0.0005 (12)	−0.0026 (11)	0.0034 (11)
C11	0.0460 (12)	0.0415 (12)	0.0499 (12)	−0.0013 (12)	−0.0086 (11)	0.0014 (11)
C16	0.0627 (16)	0.0653 (18)	0.0697 (16)	0.0142 (15)	0.0000 (14)	−0.0005 (15)
C15	0.108 (2)	0.095 (2)	0.0490 (14)	−0.002 (2)	0.0240 (17)	0.0076 (16)
C9	0.0501 (13)	0.0434 (13)	0.0413 (12)	−0.0072 (12)	−0.0032 (11)	0.0021 (11)

O2—C2	1.366 (3)	C18—H18C	0.9600
O2—C15	1.425 (3)	C14—H14	0.9300
O3—C18	1.427 (3)	C14—C13	1.393 (3)
O3—C11	1.368 (3)	C14—C9	1.383 (3)
O4—C17	1.416 (3)	C17—H17A	0.9600
O4—C13	1.374 (3)	C17—H17B	0.9600
O1—C1	1.371 (3)	C17—H17C	0.9600
O1—C16	1.416 (3)	C13—C12	1.375 (3)
C4—H4	0.9300	C12—H12	0.9300
C4—C5	1.382 (3)	C12—C11	1.383 (3)
C4—C3	1.385 (3)	C2—C3	1.373 (3)
C5—C7	1.463 (3)	C2—C1	1.407 (3)
C5—C6	1.403 (3)	C3—H3	0.9300
C7—H7	0.9300	C6—H6	0.9300
C7—C8	1.326 (3)	C6—C1	1.374 (3)
C8—H8	0.9300	C16—H16A	0.9600
C8—C9	1.472 (3)	C16—H16B	0.9600
C10—H10	0.9300	C16—H16C	0.9600
C10—C11	1.391 (3)	C15—H15A	0.9600
C10—C9	1.398 (3)	C15—H15B	0.9600
C18—H18A	0.9600	C15—H15C	0.9600
C18—H18B	0.9600
C2—O2—C15	117.2 (2)	C12—C13—O4	124.8 (2)
C11—O3—C18	117.51 (19)	C12—C13—C14	120.4 (2)
C13—O4—C17	117.9 (2)	C13—C12—H12	120.3
C1—O1—C16	117.27 (19)	C13—C12—C11	119.3 (2)
C5—C4—H4	119.5	C11—C12—H12	120.3
C5—C4—C3	121.0 (2)	O2—C2—C3	124.9 (2)
C3—C4—H4	119.5	O2—C2—C1	115.9 (2)
C4—C5—C7	119.0 (2)	C3—C2—C1	119.2 (2)
C4—C5—C6	118.1 (2)	C4—C3—H3	119.6
C6—C5—C7	122.9 (2)	C2—C3—C4	120.7 (2)
C5—C7—H7	116.3	C2—C3—H3	119.6
C8—C7—C5	127.4 (2)	C5—C6—H6	119.4
C8—C7—H7	116.3	C1—C6—C5	121.2 (2)
C7—C8—H8	116.5	C1—C6—H6	119.4
C7—C8—C9	127.0 (2)	O1—C1—C2	114.9 (2)
C9—C8—H8	116.5	O1—C1—C6	125.4 (2)
C11—C10—H10	120.3	C6—C1—C2	119.7 (2)
C11—C10—C9	119.4 (2)	O3—C11—C10	123.9 (2)
C9—C10—H10	120.3	O3—C11—C12	115.0 (2)
O3—C18—H18A	109.5	C12—C11—C10	121.1 (2)
O3—C18—H18B	109.5	O1—C16—H16A	109.5
O3—C18—H18C	109.5	O1—C16—H16B	109.5
H18A—C18—H18B	109.5	O1—C16—H16C	109.5
H18A—C18—H18C	109.5	H16A—C16—H16B	109.5
H18B—C18—H18C	109.5	H16A—C16—H16C	109.5
C13—C14—H14	119.8	H16B—C16—H16C	109.5
C9—C14—H14	119.8	O2—C15—H15A	109.5
C9—C14—C13	120.5 (2)	O2—C15—H15B	109.5
O4—C17—H17A	109.5	O2—C15—H15C	109.5
O4—C17—H17B	109.5	H15A—C15—H15B	109.5
O4—C17—H17C	109.5	H15A—C15—H15C	109.5
H17A—C17—H17B	109.5	H15B—C15—H15C	109.5
H17A—C17—H17C	109.5	C10—C9—C8	122.8 (2)
H17B—C17—H17C	109.5	C14—C9—C8	117.9 (2)
O4—C13—C14	114.8 (2)	C14—C9—C10	119.3 (2)