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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 64| Part 7| July 2008| Page o1328
doi:10.1107/S1600536808016504

(Z)-3-[1-(4-Meth­oxy­anilino)ethyl­­idene]-4,5-di­hydro­furan-2(3H)-one

Li-Ping Zhang,a* Cai-Hua Nia and Zhan-Hui Zhangb

aSchool of Chemical and Materials Engineering, Jiangnan University, 1800 Lihu Road, Wuxi 214122, Jiangsu, People's Republic of China, and bSchool of Chemistry and Materials Science, Hebei Normal University, 113 Yuhua Road, Shijiazhuang 050000, Hebei, People's Republic of China
*Correspondence e-mail: zhangliping76518@163.com.cn

(Received 28 May 2008; accepted 30 May 2008; online 21 June 2008)

In the title compound, C13H15NO3, the dihydro­furan­one ring is planar to within 0.012 (4) Å and it forms a dihedral angle of 42.8 (2)° with the benzene ring. The amino­ethyl­idene group is coplanar with the dihydro­furan­one ring. The meth­oxy group is slightly twisted away from the benzene ring. An intra­molecular N—H⋯O hydrogen bond, generating an S(6) ring, is observed. In the crystal structure, the mol­ecules exist as C—H⋯O hydrogen-bonded dimers.

Related literature

For general background, see: Bartoli et al. (1994[Bartoli, G., Cimarelli, C., Marcantoni, E., Palmieri, G. & Petrini, M. (1994). J. Org. Chem. 59, 5328-5335.]); Cimarelli & Palmieri (1996[Cimarelli, C. & Palmieri, G. (1996). J. Org. Chem. 61, 5557-5563.]); Cimarelli et al. (1994[Cimarelli, C., Palmieri, G. & Bartoli, G. (1994). Tetrahedron Asymmetry, 5, 1455-1458.]); Elassar & El-Khair (2003[Elassar, A.-Z. A. & El-Khair, A. A. (2003). Tetrahedron, 59, 8463-8480.]); Greenhill (1977[Greenhill, J. V. (1977). Chem. Soc. Rev. 6, 277-294.]); Lubell et al. (1991[Lubell, W. D., Kitamura, M. & Noyori, R. (1991). Tetrahedron Asymmetry, 2, 543-554.]); Michael et al. (1999[Michael, J. P., De Koning, C. B., Gravestock, D., Hosken, G. D. & Howard, A. S. (1999). Pure Appl. Chem. 71, 979-988.]); Negri et al. (2004[Negri, G., Kascheres, C. & Kascheres, A. J. (2004). J. Heterocycl. Chem. 41, 461-491.]); Reddy et al. (2005[Reddy, G. J., Latha, D., Thirupathaiah, C. & Rao, K. S. (2005). Tetrahedron Lett. 46, 301-302.]); Zhang et al. (2006[Zhang, Z. H., Yin, L. & Wang, Y. M. (2006). Adv. Synth. Catal. 348, 184-190.]).

[Scheme 1]

Experimental

Crystal data

  • C13H15NO3

  • Mr = 233.26

  • Orthorhombic, P b c a

  • a = 12.562 (9) Å

  • b = 7.568 (5) Å

  • c = 24.531 (18) Å

  • V = 2332 (3) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 293 (2) K

  • 0.26 × 0.20 × 0.10 mm
Data collection

  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.963, Tmax = 0.990

  • 8990 measured reflections

  • 2051 independent reflections

  • 1409 reflections with I > 2σ(I)

  • Rint = 0.051
Refinement

  • R[F2 > 2σ(F2)] = 0.064

  • wR(F2) = 0.140

  • S = 1.20

  • 2051 reflections

  • 156 parameters

  • H-atom parameters constrained

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1—H1⋯O2 0.86 2.13 2.762 (4) 130
C6—H6⋯O2i 0.93 2.53 3.405 (4) 158
Symmetry code: (i) -x+1, -y+1, -z.

Data collection: SMART (Bruker, 1998[Bruker (1998). SMART. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 1999[Bruker (1999). SAINT. Bruker AXS Inc., Madison, Wisconsin, 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: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808016504/ci2605sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808016504/ci2605Isup2.hkl

checkCIF report


Comment top

β-Enamino esters are a highly versatile class of intermediates for the synthesis of heterocycles (Reddy et al., 2005; Negri et al., 2004) and biologically active compounds, such as β-enamino acids, γ-enamino alcohols or β-enamino esters (Lubell et al., 1991; Bartoli et al., 1994; Cimarelli et al., 1994; Cimarelli & Palmieri, 1996). Many synthetic methods have been developed for the preparation of these compounds (Greenhill, 1977; Michael et al., 1999; Elassar & El-Khair, 2003). We synthesized a class of β-enamino compounds by reacting β-dicarbonyl compounds with amines in the presence of a catalytic amount of indium tribromide (Zhang et al. 2006). We report herein the crystal structure of the title compound (Fig.1).

In the title molecule, the dihydrofuranone ring is planar to within ±0.012 (4) Å and it forms a dihedral angle of 42.8 (2)° with the benzene ring. The aminoethylidene group is coplanar with the dihydrofuranone ring. The methoxy group is slightly twisted away from the benzene ring, with a C7—O1—C4—C5 torsion angle of 5.9 (5)°. The C11—C12 bond length [1.561 (5) Å] is markedly longther than usual C—C bond length. The N1—C8 bond length [1.400 (4) Å] is slightly shorter than the N1—C1 [1.439 (4) Å] bond length, indicating a weak electron delocalization. An intramolecular N1—H1···O2 hydrogen bond generating an S(6) ring is observed.

In the crystal structure, intermolecular C6—H6···O2 hydrogen bonds create centrosymmetric hydrogen-bonded dimers (Fig.2).

Related literature top

For general background, see: Bartoli et al. (1994); Cimarelli & Palmieri (1996); Cimarelli et al. (1994); Elassar & El-Khair (2003); Greenhill (1977); Lubell et al. (1991); Michael et al. (1999); Negri et al. (2004); Reddy et al. (2005); Zhang et al. (2006).

Experimental top

A mixture of the 2-acetylcyclobutanone (5 mmol), 4-methoxybenzenamine (5 mmol) and InBr3 (0.05 mmol) was stirred at room temperature for 1 h. After completion of the reaction, the reaction mixture was diluted with H2O (10 ml) and extracted with EtOAc (210 ml). The combined organic layers were dried, concentrated, purified by column chromatography on SiO2 with ethyl acetate-cyclohexane (1:8). Pale yellow solid was obtained with a yield of 89% (m.p. 339–341 K). IR (neat):ν 3526, 2976, 1683, 1628, 1513, 1475, 1228, 1114, 1029, 947, 822, 763 cm-1; 1H NMR(CDCl3, 300 MHz): δ 1.91 (s, 3H), 2.89 (t, 2H), 4.02 (s, 3H), 4.34 (t, 2H), 6.84 (d, 1H), 6.99 (d, 1H), 9.77 (br s, 1H, NH). 13C NMR(CDCl3, 75 MHz): δ 17.4, 26.4, 63.7, 65.2, 87.6, 114.8, 126.6, 131.8, 154.6, 156.8, 173.9. ESI-MS: 233(M+1)+. Analysis calculated for C13H15NO: C 66.94, H 6.48, N 6.00%; found: C 67.17, H 5.58, N 5.68%. Single crystals suitable for X-ray diffraction study were obtained from ethyl acetate-cyclohexane by slow evaporation at room temperature.

Refinement top

H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms, with N-H = 0.86 Å, C-H = 0.93–0.97 Å, and Uiso(H) = 1.5Ueq(CH3)or 1.2Ueq(C,N). Each methyl group was allowed to rotate freely about its C—C bond.

Computing details top

Data collection: SMART (Bruker, 1998); 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: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 30% probability displacement ellipsoids. The dashed line indicates a hydrogen bond.
[Figure 2] Fig. 2. The crystal packing of the title compound, showing C—H···O hydrogen-bonded dimers.
(Z)-3-[1-(4-Methoxyanilino)ethylidene]-4,5-dihydrofuran-2(3H)-one top
Crystal data top
C13H15NO3F(000) = 992
Mr = 233.26Dx = 1.329 Mg m−3
Dm = 1.329 Mg m−3
Dm measured by not measured
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 2424 reflections
a = 12.562 (9) Åθ = 2.3–26.5°
b = 7.568 (5) ŵ = 0.10 mm−1
c = 24.531 (18) ÅT = 293 K
V = 2332 (3) Å3Block, yellow
Z = 80.26 × 0.20 × 0.10 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer		2051 independent reflections
Radiation source: fine-focus sealed tube1409 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.051
ϕ and ω scansθmax = 25.0°, θmin = 1.7°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −6→14
Tmin = 0.963, Tmax = 0.990k = −6→9
8990 measured reflectionsl = −29→27
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)] = 0.064Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.140H-atom parameters constrained
S = 1.20 w = 1/[σ2(Fo2) + (0.0345P)2 + 1.787P]
where P = (Fo2 + 2Fc2)/3
2051 reflections(Δ/σ)max = 0.001
156 parametersΔρmax = 0.18 e Å−3
0 restraintsΔρmin = −0.21 e Å−3
Crystal data top
C13H15NO3V = 2332 (3) Å3
Mr = 233.26Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 12.562 (9) ŵ = 0.10 mm−1
b = 7.568 (5) ÅT = 293 K
c = 24.531 (18) Å0.26 × 0.20 × 0.10 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer		2051 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		1409 reflections with I > 2σ(I)
Tmin = 0.963, Tmax = 0.990Rint = 0.051
8990 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0640 restraints
wR(F2) = 0.140H-atom parameters constrained
S = 1.20Δρmax = 0.18 e Å−3
2051 reflectionsΔρmin = −0.21 e Å−3
156 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*/Ueq
O10.60436 (17)0.4248 (3)0.28822 (9)0.0584 (7)
O20.56144 (16)0.3225 (3)−0.03039 (9)0.0577 (7)
O30.67421 (17)0.2671 (3)−0.09776 (9)0.0588 (7)
N10.66238 (18)0.4237 (3)0.06464 (10)0.0458 (7)
H10.60530.43650.04570.055*
C10.6483 (2)0.4258 (4)0.12125 (12)0.0359 (7)
C20.7161 (2)0.3370 (4)0.15658 (12)0.0418 (7)
H20.77360.27400.14270.050*
C30.6988 (2)0.3416 (4)0.21161 (12)0.0445 (8)
H30.74540.28320.23490.053*
C40.6133 (2)0.4313 (4)0.23285 (12)0.0397 (7)
C50.5438 (2)0.5155 (4)0.19836 (12)0.0408 (7)
H50.48450.57390.21220.049*
C60.5626 (2)0.5127 (4)0.14287 (12)0.0402 (7)
H60.51590.57120.11960.048*
C70.5122 (3)0.4963 (5)0.31207 (14)0.0639 (10)
H7A0.51030.62140.30580.096*
H7B0.51290.47380.35060.096*
H7C0.45040.44240.29610.096*
C80.7527 (2)0.4043 (4)0.03547 (11)0.0379 (7)
C90.8577 (2)0.4487 (4)0.06065 (13)0.0474 (8)
H9A0.89600.34170.06830.071*
H9B0.84640.51280.09390.071*
H9C0.89830.52010.03580.071*
C100.7493 (2)0.3554 (4)−0.01772 (11)0.0398 (7)
C110.8409 (2)0.3275 (5)−0.05534 (12)0.0511 (8)
H11A0.88770.2350−0.04210.061*
H11B0.88160.4353−0.06010.061*
C120.7864 (3)0.2733 (5)−0.10790 (14)0.0625 (10)
H12A0.80190.3582−0.13650.075*
H12B0.81180.1582−0.11950.075*
C130.6529 (3)0.3163 (4)−0.04569 (12)0.0450 (8)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0501 (14)0.0825 (18)0.0428 (14)0.0102 (13)0.0055 (11)0.0044 (12)
O20.0335 (12)0.0875 (18)0.0520 (14)−0.0095 (12)−0.0071 (10)−0.0009 (12)
O30.0559 (14)0.0769 (17)0.0435 (13)−0.0083 (13)−0.0030 (11)−0.0100 (11)
N10.0240 (13)0.0681 (18)0.0452 (16)0.0017 (12)−0.0050 (11)−0.0001 (13)
C10.0293 (15)0.0367 (16)0.0416 (17)−0.0034 (13)−0.0038 (13)−0.0004 (13)
C20.0341 (16)0.0391 (17)0.0522 (19)0.0082 (14)0.0008 (14)−0.0047 (14)
C30.0389 (18)0.0450 (19)0.050 (2)0.0052 (15)−0.0065 (14)0.0042 (15)
C40.0347 (16)0.0399 (17)0.0444 (19)−0.0048 (14)0.0002 (13)0.0017 (13)
C50.0265 (15)0.0430 (18)0.0528 (19)0.0057 (13)0.0053 (14)0.0017 (14)
C60.0262 (15)0.0436 (18)0.0510 (19)0.0019 (13)−0.0058 (13)0.0071 (14)
C70.054 (2)0.085 (3)0.053 (2)0.000 (2)0.0131 (17)−0.0049 (19)
C80.0307 (15)0.0367 (16)0.0463 (18)0.0035 (13)−0.0058 (14)0.0018 (13)
C90.0352 (17)0.055 (2)0.052 (2)−0.0022 (15)−0.0074 (14)−0.0030 (15)
C100.0354 (16)0.0401 (17)0.0438 (18)−0.0025 (14)0.0001 (14)0.0017 (14)
C110.0454 (19)0.054 (2)0.054 (2)0.0036 (16)0.0042 (16)−0.0014 (16)
C120.061 (2)0.072 (3)0.055 (2)0.001 (2)0.0083 (18)−0.0076 (18)
C130.045 (2)0.0480 (19)0.0417 (19)−0.0052 (16)−0.0050 (15)0.0015 (14)
Geometric parameters (Å, º) top
O1—C41.364 (4)C6—H60.93
O1—C71.406 (4)C7—H7A0.96
O2—C131.209 (4)C7—H7B0.96
O3—C131.357 (4)C7—H7C0.96
O3—C121.432 (4)C8—C101.357 (4)
N1—C81.349 (4)C8—C91.495 (4)
N1—C11.400 (4)C9—H9A0.96
N1—H10.86C9—H9B0.96
C1—C61.368 (4)C9—H9C0.96
C1—C21.389 (4)C10—C131.424 (4)
C2—C31.368 (4)C10—C111.490 (4)
C2—H20.93C11—C121.516 (4)
C3—C41.374 (4)C11—H11A0.97
C3—H30.93C11—H11B0.97
C4—C51.372 (4)C12—H12A0.97
C5—C61.382 (4)C12—H12B0.97
C5—H50.93
C4—O1—C7117.9 (3)H7B—C7—H7C109.5
C13—O3—C12110.4 (2)N1—C8—C10120.9 (3)
C8—N1—C1129.3 (2)N1—C8—C9119.9 (3)
C8—N1—H1115.3C10—C8—C9119.1 (3)
C1—N1—H1115.3C8—C9—H9A109.5
C6—C1—C2118.2 (3)C8—C9—H9B109.5
C6—C1—N1119.3 (3)H9A—C9—H9B109.5
C2—C1—N1122.4 (3)C8—C9—H9C109.5
C3—C2—C1120.4 (3)H9A—C9—H9C109.5
C3—C2—H2119.8H9B—C9—H9C109.5
C1—C2—H2119.8C8—C10—C13123.1 (3)
C2—C3—C4120.8 (3)C8—C10—C11127.6 (3)
C2—C3—H3119.6C13—C10—C11109.2 (3)
C4—C3—H3119.6C10—C11—C12102.5 (3)
O1—C4—C5125.3 (3)C10—C11—H11A111.3
O1—C4—C3115.1 (3)C12—C11—H11A111.3
C5—C4—C3119.5 (3)C10—C11—H11B111.3
C4—C5—C6119.4 (3)C12—C11—H11B111.3
C4—C5—H5120.3H11A—C11—H11B109.2
C6—C5—H5120.3O3—C12—C11107.8 (3)
C1—C6—C5121.6 (3)O3—C12—H12A110.1
C1—C6—H6119.2C11—C12—H12A110.1
C5—C6—H6119.2O3—C12—H12B110.1
O1—C7—H7A109.5C11—C12—H12B110.1
O1—C7—H7B109.5H12A—C12—H12B108.5
H7A—C7—H7B109.5O2—C13—O3119.4 (3)
O1—C7—H7C109.5O2—C13—C10130.6 (3)
H7A—C7—H7C109.5O3—C13—C10110.0 (3)
C8—N1—C1—C6154.5 (3)C1—N1—C8—C9−23.1 (5)
C8—N1—C1—C2−28.0 (5)N1—C8—C10—C13−2.0 (4)
C6—C1—C2—C3−2.0 (4)C9—C8—C10—C13−177.9 (3)
N1—C1—C2—C3−179.5 (3)N1—C8—C10—C11−179.7 (3)
C1—C2—C3—C41.1 (5)C9—C8—C10—C114.4 (5)
C7—O1—C4—C55.9 (5)C8—C10—C11—C12179.4 (3)
C7—O1—C4—C3−172.8 (3)C13—C10—C11—C121.4 (3)
C2—C3—C4—O1179.5 (3)C13—O3—C12—C111.9 (4)
C2—C3—C4—C50.8 (5)C10—C11—C12—O3−1.9 (4)
O1—C4—C5—C6179.6 (3)C12—O3—C13—O2178.4 (3)
C3—C4—C5—C6−1.8 (4)C12—O3—C13—C10−1.0 (4)
C2—C1—C6—C51.0 (4)C8—C10—C13—O22.3 (5)
N1—C1—C6—C5178.5 (3)C11—C10—C13—O2−179.6 (3)
C4—C5—C6—C10.9 (4)C8—C10—C13—O3−178.5 (3)
C1—N1—C8—C10161.0 (3)C11—C10—C13—O3−0.4 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O20.862.132.762 (4)130
C6—H6···O2i0.932.533.405 (4)158
Symmetry code: (i) −x+1, −y+1, −z.

Experimental details

Crystal data
Chemical formulaC13H15NO3
Mr233.26
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)293
a, b, c (Å)12.562 (9), 7.568 (5), 24.531 (18)
V (Å3)2332 (3)
Z8
Radiation typeMo Kα
µ (mm−1)0.10
Crystal size (mm)0.26 × 0.20 × 0.10
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.963, 0.990
No. of measured, independent and
observed [I > 2σ(I)] reflections		8990, 2051, 1409
Rint0.051
(sin θ/λ)max (Å−1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.064, 0.140, 1.20
No. of reflections2051
No. of parameters156
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.18, −0.21

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1999), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O20.862.132.762 (4)130
C6—H6···O2i0.932.533.405 (4)158
Symmetry code: (i) −x+1, −y+1, −z.
 

Acknowledgements

The authors acknowledge financial support from Jiangnan University.

References

First citationBartoli, G., Cimarelli, C., Marcantoni, E., Palmieri, G. & Petrini, M. (1994). J. Org. Chem. 59, 5328–5335.  CrossRef CAS Web of Science Google Scholar
 First citationBruker (1998). SMART. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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ISSN: 2056-9890
Volume 64| Part 7| July 2008| Page o1328
doi:10.1107/S1600536808016504
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