(2E)-Methyl 2-(7-benz­yloxy-1-naphth­yl)-3-meth­oxy­acrylate

Zhu, X.; Li, H.; Yang, J.; Li, H.

doi:10.1107/S1600536810020994

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 66| Part 7| July 2010| Page o1600

doi:10.1107/S1600536810020994

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(2E)-Methyl 2-(7-benzyloxy-1-naphthyl)-3-methoxyacrylate

Xin Zhu,^a ^* Heping Li,^a Jing Yang ^a and Hui Li ^b

^aCollege of Pharmacy, Henan University of Traditional Chinese Medicine, Zhengzhou, Henan 450008, People's Republic of China, and ^bDepartment of Chemistry, Zhengzhou University, Zhengzhou, Henan 450052, People's Republic of China
^*Correspondence e-mail: xerz2@126.com

(Received 28 April 2010; accepted 2 June 2010; online 9 June 2010)

In the title compound, C₂₂H₂₀O₄, the dihedral angle between the phenyl and naphthalene ring systems is 86.10 (10)°. The methoxyacrylate group is disordered over two orientations in a 0.905 (3):0.095 (3) ratio.

Related literature

For bond-length data, see: Allen et al. (1987 ). For a related synthesis and crystal structure, see: Fun et al. (2008 ). For general background to and applications of compounds containing aromatic rings, see: Gunatilaka (2006 ); Kozikowski et al. (2000 ). Methylene carbonyl compounds are often found in biologically active natural compounds, see: Gotthardt & Weisshuhn (1978 ); Shono et al. (1979 ).

Experimental

Crystal data

C₂₂H₂₀O₄
M_r = 348.38
Monoclinic, P 2₁ /n
a = 10.996 (5) Å
b = 7.873 (5) Å
c = 21.417 (5) Å
β = 102.493 (5)°
V = 1810.2 (15) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 293 K
0.4 × 0.4 × 0.3 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2000 ) T_min = 0.826, T_max = 0.973
21877 measured reflections
4203 independent reflections
3273 reflections with I > 2σ(I)
R_int = 0.025

Refinement

R[F² > 2σ(F²)] = 0.044
wR(F²) = 0.131
S = 1.04
4203 reflections
247 parameters
H-atom parameters constrained
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Data collection: SMART (Bruker, 2001 ); cell refinement: SAINT (Bruker, 1999 ); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810020994/zq2038sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810020994/zq2038Isup2.hkl

checkCIF report

Comment top

Ether compounds containing aromatic rings are present in many bioactivity compounds and are useful intermediates in organic synthesis (Kozikowski et al., 2000; Gunatilaka, 2006). Methylene carbonyl compounds have been studied extensively in recent years, since they are not only useful as synthetic intermediates but also often found in biologically active natural compounds (Gotthardt et al., 1978; Shono et al., 1979). Here we report the synthesis and the crystal structure of the title compound C₂₂H₂₀O₄, namely (E)-methyl 2-(7-(benzyloxy)naphthalen-1-yl)-3-methoxyacrylate (I).

In the crystal structure, the molecule of (I) adopts two different conformations according to the relative position of the methoxyacrylate group. The minor and major conformers could be distinguished by the disorder of the oxygen atom O2 of the carbonyl group which occupies two different sites A (bound to C19) and B (bound to C21), the refined site-occupancy factors are 0.905 (3) and 0.095 (3), respectively. The naphthalene and benzene rings are essentially planar with r.m.s. deviations of 0.0036 (14) Å and 0.0001 (3) Å, respectively. The phenyl ring is almost perpendicular to the naphthalene ring, the dihedral angle between them is 86.10 (10)°, which is different from that in methyl 2-(7-benzyloxy-1-naphthyl)-2-oxoacetate, of 43.78 (7)° (Fun et al., 2008). The dihedral angle between the mean plane of the methoxyvinyl and methoxycarbonyl groups is only 6.47 (18)°. The latter long and almost planar substituent plays an important role in the whole folded conformation of (I). Nevertheless, no classic hydrogen bonds were found in the crystal structure.

Related literature top

For bond-length data, see: Allen et al. (1987). For a related synthesis and crystal structure, see: Fun et al. (2008). For general background to and applications of compounds containing aromatic rings, see: Gunatilaka (2006); Kozikowski et al. (2000). Methylene carbonyl compounds are often found in biologically active natural compounds, see: Gotthardt & Weisshuhn (1978); Shono et al. (1979).

Experimental top

Methyl 2-(7-benzyloxy-1-naphthyl)-2-oxoacetate was synthesized according with a published procedure (Fun et al., 2008). To a solution of methyl 2-(7-benzyloxy-1-naphthyl)-2-oxoacetate (4 g, 12.5 mmol) in dry THF (10 ml) was slowly added an excess of (methoxymethyl)triphenylphosphonium chloride (5.1 g, 20 mmol) in dry ether and 2.5 M butyl lithium in hexane (6 ml) under nitrogen. The mixture was allowed to warm to room temperature for 24 h, and then was quenched with dilute hydrochloric acid. The crude product was purified by column chromatography with petroleum ether - ethyl acetate (5: 1) as the eluent, to afford I as a white powder (0.5 g, 11.9%). Single crystals suitable for a X-ray analysis were obtained by slow evaporation from ethanol at room temperature for several days (m.p. 125–126°C).

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of (I) showing 30% probability displacement ellipsoids and the atomic numbering.

(2E)-Methyl 2-(7-benzyloxy-1-naphthyl)-3-methoxyacrylate top

Crystal data top

C₂₂H₂₀O₄	F(000) = 736
M_r = 348.38	D_x = 1.278 Mg m⁻³
Monoclinic, P2₁/n	Melting point = 398–399 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 10.996 (5) Å	Cell parameters from 7659 reflections
b = 7.873 (5) Å	θ = 2.3–27.6°
c = 21.417 (5) Å	µ = 0.09 mm⁻¹
β = 102.493 (5)°	T = 293 K
V = 1810.2 (15) Å³	Block, colorless
Z = 4	0.4 × 0.4 × 0.3 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	4203 independent reflections
Radiation source: fine-focus sealed tube	3273 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.025
phi and ω scans	θ_max = 27.6°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −14→14
T_min = 0.826, T_max = 0.973	k = −10→9
21877 measured reflections	l = −27→27

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)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.131	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0575P)² + 0.3948P] where P = (F_o² + 2F_c²)/3
4203 reflections	(Δ/σ)_max = 0.020
247 parameters	Δρ_max = 0.19 e Å⁻³
0 restraints	Δρ_min = −0.17 e Å⁻³

Crystal data top

C₂₂H₂₀O₄	V = 1810.2 (15) Å³
M_r = 348.38	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 10.996 (5) Å	µ = 0.09 mm⁻¹
b = 7.873 (5) Å	T = 293 K
c = 21.417 (5) Å	0.4 × 0.4 × 0.3 mm
β = 102.493 (5)°

Data collection top

Bruker SMART CCD area-detector diffractometer	4203 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2000)	3273 reflections with I > 2σ(I)
T_min = 0.826, T_max = 0.973	R_int = 0.025
21877 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.044	0 restraints
wR(F²) = 0.131	H-atom parameters constrained
S = 1.04	Δρ_max = 0.19 e Å⁻³
4203 reflections	Δρ_min = −0.17 e Å⁻³
247 parameters

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
C1	0.89564 (15)	0.8419 (2)	0.43935 (8)	0.0617 (4)
H1	0.9075	0.9125	0.4750	0.074*
C2	0.9022 (2)	0.6687 (3)	0.44746 (13)	0.0899 (7)
H2	0.9175	0.6215	0.4882	0.108*
C3	0.8857 (2)	0.5660 (3)	0.39409 (18)	0.1101 (9)
H3	0.8900	0.4486	0.3991	0.132*
C4	0.8631 (2)	0.6339 (3)	0.33425 (16)	0.1042 (8)
H4	0.8528	0.5629	0.2988	0.125*
C5	0.85536 (18)	0.8070 (3)	0.32603 (10)	0.0768 (5)
H5	0.8392	0.8531	0.2851	0.092*
C6	0.87165 (13)	0.91229 (19)	0.37869 (7)	0.0515 (3)
C7	0.85480 (15)	1.1015 (2)	0.37234 (7)	0.0554 (4)
H7A	0.7704	1.1295	0.3755	0.067*
H7B	0.9111	1.1558	0.4079	0.067*
C8	0.99755 (14)	1.19352 (19)	0.30829 (6)	0.0497 (3)
C9	1.00816 (16)	1.2723 (2)	0.25038 (7)	0.0591 (4)
H9	0.9368	1.3001	0.2200	0.071*
C10	1.12174 (16)	1.3073 (2)	0.23908 (7)	0.0573 (4)
H10	1.1274	1.3592	0.2008	0.069*
C11	1.23257 (14)	1.26688 (17)	0.28418 (6)	0.0464 (3)
C12	1.22164 (13)	1.18630 (16)	0.34233 (6)	0.0411 (3)
C13	1.10149 (13)	1.15120 (17)	0.35316 (6)	0.0437 (3)
H13	1.0934	1.0991	0.3910	0.052*
C14	1.35110 (16)	1.3059 (2)	0.27324 (7)	0.0563 (4)
H14	1.3578	1.3577	0.2351	0.068*
C15	1.45600 (16)	1.2686 (2)	0.31784 (7)	0.0580 (4)
H15	1.5338	1.2961	0.3103	0.070*
C16	1.44661 (14)	1.18867 (19)	0.37519 (7)	0.0513 (3)
H16	1.5189	1.1635	0.4053	0.062*
C17	1.33331 (13)	1.14669 (16)	0.38795 (6)	0.0421 (3)
C18	1.32816 (12)	1.06687 (17)	0.45059 (6)	0.0431 (3)
C19	1.28723 (12)	0.89191 (18)	0.45565 (6)	0.0457 (3)
H19	1.2753	0.8435	0.4935	0.055*	0.095 (3)
O2A	1.26989 (13)	0.82617 (16)	0.50464 (5)	0.0647 (4)	0.905 (3)
C20	1.22339 (19)	0.6374 (2)	0.39907 (9)	0.0704 (5)
H20A	1.2762	0.5730	0.4323	0.106*
H20B	1.2236	0.5868	0.3583	0.106*
H20C	1.1400	0.6380	0.4060	0.106*
C21	1.36400 (13)	1.15235 (19)	0.50605 (6)	0.0495 (3)
H21	1.3621	1.0975	0.5443	0.059*	0.905 (3)
O2B	1.3729 (13)	1.076 (2)	0.5625 (5)	0.084 (5)	0.095 (3)
C22	1.43189 (19)	1.3923 (3)	0.56949 (8)	0.0780 (5)
H22A	1.3574	1.4053	0.5855	0.117*
H22B	1.4680	1.5019	0.5659	0.117*
H22C	1.4902	1.3228	0.5984	0.117*
O1	0.87669 (10)	1.16997 (16)	0.31413 (5)	0.0632 (3)
O3	1.26886 (10)	0.80927 (12)	0.39999 (5)	0.0546 (3)
O4	1.40199 (12)	1.31265 (15)	0.50759 (5)	0.0662 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0605 (9)	0.0539 (9)	0.0707 (10)	0.0037 (7)	0.0145 (8)	0.0037 (8)
C2	0.0809 (13)	0.0625 (12)	0.1244 (19)	0.0085 (10)	0.0181 (12)	0.0259 (12)
C3	0.0878 (16)	0.0439 (11)	0.194 (3)	0.0031 (10)	0.0207 (18)	−0.0089 (16)
C4	0.0886 (15)	0.0765 (15)	0.140 (2)	0.0046 (12)	0.0081 (15)	−0.0512 (16)
C5	0.0719 (11)	0.0777 (13)	0.0778 (12)	0.0062 (9)	0.0099 (9)	−0.0239 (10)
C6	0.0437 (7)	0.0521 (8)	0.0597 (8)	0.0019 (6)	0.0135 (6)	−0.0058 (7)
C7	0.0574 (8)	0.0559 (9)	0.0572 (8)	0.0078 (7)	0.0216 (7)	0.0049 (7)
C8	0.0570 (8)	0.0514 (8)	0.0415 (7)	0.0089 (6)	0.0122 (6)	0.0052 (6)
C9	0.0684 (10)	0.0673 (10)	0.0396 (7)	0.0144 (8)	0.0074 (7)	0.0125 (7)
C10	0.0792 (11)	0.0581 (9)	0.0362 (7)	0.0076 (8)	0.0160 (7)	0.0133 (6)
C11	0.0671 (9)	0.0404 (7)	0.0332 (6)	−0.0003 (6)	0.0144 (6)	0.0016 (5)
C12	0.0587 (8)	0.0342 (6)	0.0314 (6)	0.0007 (5)	0.0118 (5)	−0.0012 (5)
C13	0.0580 (8)	0.0413 (7)	0.0332 (6)	0.0042 (6)	0.0129 (5)	0.0055 (5)
C14	0.0783 (10)	0.0531 (9)	0.0423 (7)	−0.0088 (7)	0.0238 (7)	0.0048 (6)
C15	0.0643 (9)	0.0628 (10)	0.0515 (8)	−0.0155 (8)	0.0223 (7)	−0.0018 (7)
C16	0.0568 (8)	0.0534 (8)	0.0438 (7)	−0.0064 (7)	0.0111 (6)	−0.0024 (6)
C17	0.0571 (8)	0.0377 (6)	0.0326 (6)	−0.0025 (6)	0.0119 (5)	−0.0024 (5)
C18	0.0478 (7)	0.0468 (7)	0.0341 (6)	0.0029 (6)	0.0079 (5)	0.0027 (5)
C19	0.0497 (7)	0.0477 (8)	0.0396 (6)	0.0056 (6)	0.0092 (5)	0.0053 (6)
O2A	0.0923 (10)	0.0599 (8)	0.0444 (7)	−0.0086 (6)	0.0204 (6)	0.0093 (5)
C20	0.0862 (12)	0.0485 (9)	0.0765 (11)	−0.0104 (8)	0.0171 (9)	−0.0040 (8)
C21	0.0541 (8)	0.0563 (9)	0.0373 (6)	0.0015 (7)	0.0080 (6)	0.0019 (6)
O2B	0.084 (9)	0.134 (14)	0.030 (6)	0.019 (9)	0.008 (5)	0.004 (7)
C22	0.0847 (12)	0.0914 (14)	0.0562 (10)	−0.0192 (10)	0.0114 (8)	−0.0297 (9)
O1	0.0549 (6)	0.0787 (8)	0.0559 (6)	0.0109 (5)	0.0117 (5)	0.0176 (5)
O3	0.0762 (7)	0.0432 (5)	0.0462 (5)	−0.0023 (5)	0.0168 (5)	−0.0016 (4)
O4	0.0954 (9)	0.0593 (7)	0.0424 (6)	−0.0142 (6)	0.0114 (5)	−0.0093 (5)

Geometric parameters (Å, º) top

C1—C2	1.375 (3)	C12—C13	1.417 (2)
C1—C6	1.384 (2)	C12—C17	1.4285 (19)
C1—H1	0.9300	C13—H13	0.9300
C2—C3	1.380 (4)	C14—C15	1.361 (2)
C2—H2	0.9300	C14—H14	0.9300
C3—C4	1.361 (4)	C15—C16	1.404 (2)
C3—H3	0.9300	C15—H15	0.9300
C4—C5	1.375 (3)	C16—C17	1.372 (2)
C4—H4	0.9300	C16—H16	0.9300
C5—C6	1.380 (2)	C17—C18	1.4936 (17)
C5—H5	0.9300	C18—C21	1.3477 (19)
C6—C7	1.504 (2)	C18—C19	1.460 (2)
C7—O1	1.4255 (17)	C19—O3	1.3345 (16)
C7—H7A	0.9700	C19—H19	0.9300
C7—H7B	0.9700	C20—O3	1.441 (2)
C8—C13	1.366 (2)	C20—H20A	0.9600
C8—O1	1.3741 (19)	C20—H20B	0.9600
C8—C9	1.414 (2)	C20—H20C	0.9600
C9—C10	1.351 (2)	C21—O4	1.328 (2)
C9—H9	0.9300	C21—H21	0.9300
C10—C11	1.418 (2)	C22—O4	1.4388 (18)
C10—H10	0.9300	C22—H22A	0.9600
C11—C14	1.407 (2)	C22—H22B	0.9600
C11—C12	1.4258 (17)	C22—H22C	0.9600

C2—C1—C6	120.64 (19)	C8—C13—C12	120.35 (12)
C2—C1—H1	119.7	C8—C13—H13	119.8
C6—C1—H1	119.7	C12—C13—H13	119.8
C1—C2—C3	118.9 (2)	C15—C14—C11	120.73 (13)
C1—C2—H2	120.6	C15—C14—H14	119.6
C3—C2—H2	120.6	C11—C14—H14	119.6
C4—C3—C2	121.0 (2)	C14—C15—C16	119.95 (14)
C4—C3—H3	119.5	C14—C15—H15	120.0
C2—C3—H3	119.5	C16—C15—H15	120.0
C3—C4—C5	120.2 (2)	C17—C16—C15	121.60 (14)
C3—C4—H4	119.9	C17—C16—H16	119.2
C5—C4—H4	119.9	C15—C16—H16	119.2
C4—C5—C6	119.8 (2)	C16—C17—C12	119.62 (12)
C4—C5—H5	120.1	C16—C17—C18	119.51 (12)
C6—C5—H5	120.1	C12—C17—C18	120.81 (11)
C5—C6—C1	119.45 (17)	C21—C18—C19	116.21 (12)
C5—C6—C7	121.96 (16)	C21—C18—C17	121.38 (13)
C1—C6—C7	118.43 (14)	C19—C18—C17	122.39 (11)
O1—C7—C6	114.39 (13)	O3—C19—C18	112.53 (11)
O1—C7—H7A	108.7	O3—C19—H19	123.7
C6—C7—H7A	108.7	C18—C19—H19	123.7
O1—C7—H7B	108.7	O3—C20—H20A	109.5
C6—C7—H7B	108.7	O3—C20—H20B	109.5
H7A—C7—H7B	107.6	H20A—C20—H20B	109.5
C13—C8—O1	125.56 (12)	O3—C20—H20C	109.5
C13—C8—C9	120.59 (14)	H20A—C20—H20C	109.5
O1—C8—C9	113.83 (13)	H20B—C20—H20C	109.5
C10—C9—C8	120.10 (14)	O4—C21—C18	121.81 (13)
C10—C9—H9	120.0	O4—C21—H21	119.1
C8—C9—H9	120.0	C18—C21—H21	119.1
C9—C10—C11	121.59 (13)	O4—C22—H22A	109.5
C9—C10—H10	119.2	O4—C22—H22B	109.5
C11—C10—H10	119.2	H22A—C22—H22B	109.5
C14—C11—C10	121.88 (13)	O4—C22—H22C	109.5
C14—C11—C12	119.91 (13)	H22A—C22—H22C	109.5
C10—C11—C12	118.20 (13)	H22B—C22—H22C	109.5
C13—C12—C11	119.17 (12)	C8—O1—C7	118.70 (11)
C13—C12—C17	122.65 (11)	C19—O3—C20	117.07 (12)
C11—C12—C17	118.17 (12)	C21—O4—C22	116.43 (13)

Experimental details

Crystal data
Chemical formula	C₂₂H₂₀O₄
M_r	348.38
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	293
a, b, c (Å)	10.996 (5), 7.873 (5), 21.417 (5)
β (°)	102.493 (5)
V (Å³)	1810.2 (15)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.4 × 0.4 × 0.3

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2000)
T_min, T_max	0.826, 0.973
No. of measured, independent and observed [I > 2σ(I)] reflections	21877, 4203, 3273
R_int	0.025
(sin θ/λ)_max (Å⁻¹)	0.653

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.044, 0.131, 1.04
No. of reflections	4203
No. of parameters	247
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.19, −0.17

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 1999), SAINT (Bruker, 1999, SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

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