organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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COMMUNICATIONS
ISSN: 2056-9890

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

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[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For a related synthesis and crystal structure, see: Fun et al. (2008[Fun, H.-K., Chantrapromma, S., Li, S.-X. & Li, H.-M. (2008). Acta Cryst. E64, o1409.]). For general background to and applications of compounds containing aromatic rings, see: Gunatilaka (2006[Gunatilaka, A. A. L. (2006). J. Nat. Prod. 69, 509-526.]); Kozikowski et al. (2000[Kozikowski, A. P., Tuckmantel, W. & George, C. J. (2000). J. Org. Chem. 65, 5371-5381.]). Methyl­ene carbonyl compounds are often found in biologically active natural compounds, see: Gotthardt & Weisshuhn (1978[Gotthardt, H. & Weisshuhn, C. M. (1978). Chem. Ber. 111, 3171-3177.]); Shono et al. (1979[Shono, T., Nishiguchi, I., Komamura, T. & Sasaki, M. (1979). J. Am. Chem. Soc. 101, 984-987.]).

[Scheme 1]

Experimental

Crystal data
  • C22H20O4

  • Mr = 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[Bruker (2000). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.826, Tmax = 0.973

  • 21877 measured reflections

  • 4203 independent reflections

  • 3273 reflections with I > 2σ(I)

  • Rint = 0.025

Refinement
  • R[F2 > 2σ(F2)] = 0.044

  • wR(F2) = 0.131

  • S = 1.04

  • 4203 reflections

  • 247 parameters

  • H-atom parameters constrained

  • Δρmax = 0.19 e Å−3

  • Δρmin = −0.17 e Å−3

Data collection: SMART (Bruker, 2001[Bruker (2001). SMART. Bruker AXS Inc., Madison, Wisconson, USA.]); cell refinement: SAINT (Bruker, 1999[Bruker (1999). SAINT. Bruker AXS Inc., Madison, Wisconson, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXL97.

Supporting information


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).

Refinement top

All H atoms were positioned geometrically and refined as riding atoms, with C—H = 0.93Å and Uiso = 1.2Ueq(C) for aromatic hydrogen atoms, with C—H = 0.97 Å and Uiso = 1.2Ueq(C) for methylene hydrogen atoms, and with C—H=0.96 Å and Uiso = 1.5Ueq(C) for methyl hydrogen atoms. 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.

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
[Figure 1] 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
C22H20O4F(000) = 736
Mr = 348.38Dx = 1.278 Mg m3
Monoclinic, P21/nMelting point = 398–399 K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 10.996 (5) ÅCell parameters from 7659 reflections
b = 7.873 (5) Åθ = 2.3–27.6°
c = 21.417 (5) ŵ = 0.09 mm1
β = 102.493 (5)°T = 293 K
V = 1810.2 (15) Å3Block, colorless
Z = 40.4 × 0.4 × 0.3 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
4203 independent reflections
Radiation source: fine-focus sealed tube3273 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.025
phi and ω scansθmax = 27.6°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
h = 1414
Tmin = 0.826, Tmax = 0.973k = 109
21877 measured reflectionsl = 2727
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.131H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0575P)2 + 0.3948P]
where P = (Fo2 + 2Fc2)/3
4203 reflections(Δ/σ)max = 0.020
247 parametersΔρmax = 0.19 e Å3
0 restraintsΔρmin = 0.17 e Å3
Crystal data top
C22H20O4V = 1810.2 (15) Å3
Mr = 348.38Z = 4
Monoclinic, P21/nMo Kα radiation
a = 10.996 (5) ŵ = 0.09 mm1
b = 7.873 (5) ÅT = 293 K
c = 21.417 (5) Å0.4 × 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)
Tmin = 0.826, Tmax = 0.973Rint = 0.025
21877 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0440 restraints
wR(F2) = 0.131H-atom parameters constrained
S = 1.04Δρmax = 0.19 e Å3
4203 reflectionsΔρmin = 0.17 e Å3
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
xyzUiso*/UeqOcc. (<1)
C10.89564 (15)0.8419 (2)0.43935 (8)0.0617 (4)
H10.90750.91250.47500.074*
C20.9022 (2)0.6687 (3)0.44746 (13)0.0899 (7)
H20.91750.62150.48820.108*
C30.8857 (2)0.5660 (3)0.39409 (18)0.1101 (9)
H30.89000.44860.39910.132*
C40.8631 (2)0.6339 (3)0.33425 (16)0.1042 (8)
H40.85280.56290.29880.125*
C50.85536 (18)0.8070 (3)0.32603 (10)0.0768 (5)
H50.83920.85310.28510.092*
C60.87165 (13)0.91229 (19)0.37869 (7)0.0515 (3)
C70.85480 (15)1.1015 (2)0.37234 (7)0.0554 (4)
H7A0.77041.12950.37550.067*
H7B0.91111.15580.40790.067*
C80.99755 (14)1.19352 (19)0.30829 (6)0.0497 (3)
C91.00816 (16)1.2723 (2)0.25038 (7)0.0591 (4)
H90.93681.30010.22000.071*
C101.12174 (16)1.3073 (2)0.23908 (7)0.0573 (4)
H101.12741.35920.20080.069*
C111.23257 (14)1.26688 (17)0.28418 (6)0.0464 (3)
C121.22164 (13)1.18630 (16)0.34233 (6)0.0411 (3)
C131.10149 (13)1.15120 (17)0.35316 (6)0.0437 (3)
H131.09341.09910.39100.052*
C141.35110 (16)1.3059 (2)0.27324 (7)0.0563 (4)
H141.35781.35770.23510.068*
C151.45600 (16)1.2686 (2)0.31784 (7)0.0580 (4)
H151.53381.29610.31030.070*
C161.44661 (14)1.18867 (19)0.37519 (7)0.0513 (3)
H161.51891.16350.40530.062*
C171.33331 (13)1.14669 (16)0.38795 (6)0.0421 (3)
C181.32816 (12)1.06687 (17)0.45059 (6)0.0431 (3)
C191.28723 (12)0.89191 (18)0.45565 (6)0.0457 (3)
H191.27530.84350.49350.055*0.095 (3)
O2A1.26989 (13)0.82617 (16)0.50464 (5)0.0647 (4)0.905 (3)
C201.22339 (19)0.6374 (2)0.39907 (9)0.0704 (5)
H20A1.27620.57300.43230.106*
H20B1.22360.58680.35830.106*
H20C1.14000.63800.40600.106*
C211.36400 (13)1.15235 (19)0.50605 (6)0.0495 (3)
H211.36211.09750.54430.059*0.905 (3)
O2B1.3729 (13)1.076 (2)0.5625 (5)0.084 (5)0.095 (3)
C221.43189 (19)1.3923 (3)0.56949 (8)0.0780 (5)
H22A1.35741.40530.58550.117*
H22B1.46801.50190.56590.117*
H22C1.49021.32280.59840.117*
O10.87669 (10)1.16997 (16)0.31413 (5)0.0632 (3)
O31.26886 (10)0.80927 (12)0.39999 (5)0.0546 (3)
O41.40199 (12)1.31265 (15)0.50759 (5)0.0662 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0605 (9)0.0539 (9)0.0707 (10)0.0037 (7)0.0145 (8)0.0037 (8)
C20.0809 (13)0.0625 (12)0.1244 (19)0.0085 (10)0.0181 (12)0.0259 (12)
C30.0878 (16)0.0439 (11)0.194 (3)0.0031 (10)0.0207 (18)0.0089 (16)
C40.0886 (15)0.0765 (15)0.140 (2)0.0046 (12)0.0081 (15)0.0512 (16)
C50.0719 (11)0.0777 (13)0.0778 (12)0.0062 (9)0.0099 (9)0.0239 (10)
C60.0437 (7)0.0521 (8)0.0597 (8)0.0019 (6)0.0135 (6)0.0058 (7)
C70.0574 (8)0.0559 (9)0.0572 (8)0.0078 (7)0.0216 (7)0.0049 (7)
C80.0570 (8)0.0514 (8)0.0415 (7)0.0089 (6)0.0122 (6)0.0052 (6)
C90.0684 (10)0.0673 (10)0.0396 (7)0.0144 (8)0.0074 (7)0.0125 (7)
C100.0792 (11)0.0581 (9)0.0362 (7)0.0076 (8)0.0160 (7)0.0133 (6)
C110.0671 (9)0.0404 (7)0.0332 (6)0.0003 (6)0.0144 (6)0.0016 (5)
C120.0587 (8)0.0342 (6)0.0314 (6)0.0007 (5)0.0118 (5)0.0012 (5)
C130.0580 (8)0.0413 (7)0.0332 (6)0.0042 (6)0.0129 (5)0.0055 (5)
C140.0783 (10)0.0531 (9)0.0423 (7)0.0088 (7)0.0238 (7)0.0048 (6)
C150.0643 (9)0.0628 (10)0.0515 (8)0.0155 (8)0.0223 (7)0.0018 (7)
C160.0568 (8)0.0534 (8)0.0438 (7)0.0064 (7)0.0111 (6)0.0024 (6)
C170.0571 (8)0.0377 (6)0.0326 (6)0.0025 (6)0.0119 (5)0.0024 (5)
C180.0478 (7)0.0468 (7)0.0341 (6)0.0029 (6)0.0079 (5)0.0027 (5)
C190.0497 (7)0.0477 (8)0.0396 (6)0.0056 (6)0.0092 (5)0.0053 (6)
O2A0.0923 (10)0.0599 (8)0.0444 (7)0.0086 (6)0.0204 (6)0.0093 (5)
C200.0862 (12)0.0485 (9)0.0765 (11)0.0104 (8)0.0171 (9)0.0040 (8)
C210.0541 (8)0.0563 (9)0.0373 (6)0.0015 (7)0.0080 (6)0.0019 (6)
O2B0.084 (9)0.134 (14)0.030 (6)0.019 (9)0.008 (5)0.004 (7)
C220.0847 (12)0.0914 (14)0.0562 (10)0.0192 (10)0.0114 (8)0.0297 (9)
O10.0549 (6)0.0787 (8)0.0559 (6)0.0109 (5)0.0117 (5)0.0176 (5)
O30.0762 (7)0.0432 (5)0.0462 (5)0.0023 (5)0.0168 (5)0.0016 (4)
O40.0954 (9)0.0593 (7)0.0424 (6)0.0142 (6)0.0114 (5)0.0093 (5)
Geometric parameters (Å, º) top
C1—C21.375 (3)C12—C131.417 (2)
C1—C61.384 (2)C12—C171.4285 (19)
C1—H10.9300C13—H130.9300
C2—C31.380 (4)C14—C151.361 (2)
C2—H20.9300C14—H140.9300
C3—C41.361 (4)C15—C161.404 (2)
C3—H30.9300C15—H150.9300
C4—C51.375 (3)C16—C171.372 (2)
C4—H40.9300C16—H160.9300
C5—C61.380 (2)C17—C181.4936 (17)
C5—H50.9300C18—C211.3477 (19)
C6—C71.504 (2)C18—C191.460 (2)
C7—O11.4255 (17)C19—O31.3345 (16)
C7—H7A0.9700C19—H190.9300
C7—H7B0.9700C20—O31.441 (2)
C8—C131.366 (2)C20—H20A0.9600
C8—O11.3741 (19)C20—H20B0.9600
C8—C91.414 (2)C20—H20C0.9600
C9—C101.351 (2)C21—O41.328 (2)
C9—H90.9300C21—H210.9300
C10—C111.418 (2)C22—O41.4388 (18)
C10—H100.9300C22—H22A0.9600
C11—C141.407 (2)C22—H22B0.9600
C11—C121.4258 (17)C22—H22C0.9600
C2—C1—C6120.64 (19)C8—C13—C12120.35 (12)
C2—C1—H1119.7C8—C13—H13119.8
C6—C1—H1119.7C12—C13—H13119.8
C1—C2—C3118.9 (2)C15—C14—C11120.73 (13)
C1—C2—H2120.6C15—C14—H14119.6
C3—C2—H2120.6C11—C14—H14119.6
C4—C3—C2121.0 (2)C14—C15—C16119.95 (14)
C4—C3—H3119.5C14—C15—H15120.0
C2—C3—H3119.5C16—C15—H15120.0
C3—C4—C5120.2 (2)C17—C16—C15121.60 (14)
C3—C4—H4119.9C17—C16—H16119.2
C5—C4—H4119.9C15—C16—H16119.2
C4—C5—C6119.8 (2)C16—C17—C12119.62 (12)
C4—C5—H5120.1C16—C17—C18119.51 (12)
C6—C5—H5120.1C12—C17—C18120.81 (11)
C5—C6—C1119.45 (17)C21—C18—C19116.21 (12)
C5—C6—C7121.96 (16)C21—C18—C17121.38 (13)
C1—C6—C7118.43 (14)C19—C18—C17122.39 (11)
O1—C7—C6114.39 (13)O3—C19—C18112.53 (11)
O1—C7—H7A108.7O3—C19—H19123.7
C6—C7—H7A108.7C18—C19—H19123.7
O1—C7—H7B108.7O3—C20—H20A109.5
C6—C7—H7B108.7O3—C20—H20B109.5
H7A—C7—H7B107.6H20A—C20—H20B109.5
C13—C8—O1125.56 (12)O3—C20—H20C109.5
C13—C8—C9120.59 (14)H20A—C20—H20C109.5
O1—C8—C9113.83 (13)H20B—C20—H20C109.5
C10—C9—C8120.10 (14)O4—C21—C18121.81 (13)
C10—C9—H9120.0O4—C21—H21119.1
C8—C9—H9120.0C18—C21—H21119.1
C9—C10—C11121.59 (13)O4—C22—H22A109.5
C9—C10—H10119.2O4—C22—H22B109.5
C11—C10—H10119.2H22A—C22—H22B109.5
C14—C11—C10121.88 (13)O4—C22—H22C109.5
C14—C11—C12119.91 (13)H22A—C22—H22C109.5
C10—C11—C12118.20 (13)H22B—C22—H22C109.5
C13—C12—C11119.17 (12)C8—O1—C7118.70 (11)
C13—C12—C17122.65 (11)C19—O3—C20117.07 (12)
C11—C12—C17118.17 (12)C21—O4—C22116.43 (13)

Experimental details

Crystal data
Chemical formulaC22H20O4
Mr348.38
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)10.996 (5), 7.873 (5), 21.417 (5)
β (°) 102.493 (5)
V3)1810.2 (15)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.4 × 0.4 × 0.3
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2000)
Tmin, Tmax0.826, 0.973
No. of measured, independent and
observed [I > 2σ(I)] reflections
21877, 4203, 3273
Rint0.025
(sin θ/λ)max1)0.653
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.044, 0.131, 1.04
No. of reflections4203
No. of parameters247
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.19, 0.17

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

 

References

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