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ISSN: 2056-9890

(Z)-3-(4-Meth­oxy­anilino)-1-phenyl­but-2-en-1-one

aSchool of Chemical and Materials Engineering, Jiangnan University, 1800 Lihu Road, Wuxi 214122, Jiangsu, People's Republic of China
*Correspondence e-mail: zlp609@qq.com

(Received 20 November 2009; accepted 27 November 2009; online 4 December 2009)

In the title compound, C17H17NO2, the dihedral angle between the two benzene rings is 6.9 (1)°. The meth­oxy group is twisted slightly away from the aniline ring [C—O—C—C = 12.2 (3)°]. An intra­molecular N—H⋯O hydrogen bond generating an S(6) ring is observed. The crystal packing is stabilized by weak C—H⋯O and C—H⋯π inter­actions, forming a two-dimensional network.

Related literature

For the biological activity of β-enamino ketones, see: Azzaro et al. (1981[Azzaro, M., Geribaldi, S. & Videau, B. (1981). Synthesis, pp. 880-881.]); Dannhardt et al. (1998[Dannhardt, G., Bauer, A. & Nowe, U. (1998). J. Prakt. Chem. 340, 256-263.]); Boger et al. (1989[Boger, D. L., Ishizaki, T., Wysocki, J. R. J., Munk, S. A., Kitos, P. A. & Suntornwat, O. (1989). J. Am. Chem. Soc. 111, 6461-6463.]); Wang et al. (1982[Wang, Y. F., Izawa, T., Kobayashi, S. & Ohno, M. (1982). J. Am. Chem. Soc. 104, 6465-6466.]). For the preparation of β-enamino ketones, see: Greenhill (1977[Greenhill, J. V. (1977). Chem. Soc. Rev. 6, 277-294.]); Elassar & El-Khair (2003[Elassar, A.-Z. A. & El-Khair, A. A. (2003). Tetrahedron, 59, 8463-8480.]); Zhang et al. (2006[Zhang, Z. H., Yin, L. & Wang, Y. M. (2006). Adv. Synth. Catal. 348, 184-190.]).

[Scheme 1]

Experimental

Crystal data
  • C17H17NO2

  • Mr = 267.32

  • Monoclinic, P 21 /n

  • a = 6.435 (2) Å

  • b = 7.287 (3) Å

  • c = 30.919 (12) Å

  • β = 94.954 (6)°

  • V = 1444.5 (9) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 294 K

  • 0.24 × 0.20 × 0.16 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 = 0.739, Tmax = 1.000

  • 7729 measured reflections

  • 2931 independent reflections

  • 1900 reflections with I > 2σ(I)

  • Rint = 0.036

Refinement
  • R[F2 > 2σ(F2)] = 0.046

  • wR(F2) = 0.135

  • S = 1.00

  • 2931 reflections

  • 184 parameters

  • H-atom parameters constrained

  • Δρmax = 0.18 e Å−3

  • Δρmin = −0.17 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O2 0.86 1.91 2.629 (2) 139
C8—H8B⋯O2i 0.96 2.49 3.351 (3) 148
C3—H3⋯Cg2ii 0.93 2.84 3.712 (3) 156
C13—H13⋯Cg1iii 0.93 2.82 3.619 (3) 145
Symmetry codes: (i) x+1, y, z; (ii) [-x-{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]. Cg1 and Cg2 are the centroids of the C1–C6 and C12–C17 rings, respectively.

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


Comment top

β-enamino ketones have attracted considerable interest, because they are versatile intermediates for the synthesis of natural therapeutic and biologically active analogues including anticonvulsant (Azzaro et al., 1981), anti-inflammatory (Dannhardt et al., 1998) and antitumor agents (Boger et al., 1989), as well as quinolone antibacterials (Wang et al., 1982). It is therefore not surprising that many synthetic methods have been developed for the preparation of these compounds (Greenhill et al., 1977; Elassar et al., 2003). During the development of new environmental friendly methodologies (Zhang et al., 2006) for the preparation of β-enamino ketones, we synthesized the title compound (Fig.1) and its crystal structure is reported here.

In the title compound, the dihedral angle between the two benzene rings is 6.9 (1)%. The methoxy group is slightly twisted away from the aniline ring, with a C7—O1—C4—C3 torsion angle of 12.2 (3)°. The C10—C11 bond length [1.415 (2) Å] is shorter than the C11—C12 bond length [1.500 (2) Å], and the N1—C9 bond length [1.333 (2) Å] is markedly shorter than the N1—C1 [1.419 (2) Å] bond length, indicating a strong electron delocalization. An intramolecular N1—H1···O2 hydrogen bond observed.

The crystal packing is stabilized by weak C—H···O and C—H···π interactions. Intermolecular C8—H8B···O2 hydrogen bonds link the molecules into a C(6) chain propagating along the a axis (Fig.2). In addition, the crystal packing is stabilized by C—H···π interactions; these interactions link the chains along the b axis, forming a two-dimensional network (Fig.2).

Related literature top

For the biological activity of β-enamino ketones, see: Azzaro et al. (1981); Dannhardt et al. (1998); Boger et al. (1989); Wang et al. (1982). For the preparation of β-enamino ketones, see: Greenhill et al. (1977); Elassar et al. (2003); Zhang et al. (2006). Cg1 and Cg2 are the centroids of the C1–C6 and C12–C17 rings, respectively.

Experimental top

A mixture of 1-phenylbutane-1,3-dione (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 (2:8), to obatin a pale yellow solid, with a yield of 78% (m. p. 84–85° C); IR (neat):ν 2979, 2870,1608, 1576, 1504, 1473, 1432,1372, 820, 744 cm-1; 1H NMR(CDCl3, 300 MHz): δ 2.06(s, 3H), 3.80(s, 3H), 5.86(s, 1H), 6.88(d, 2H,Ar—H), 7.09(d, 2H,Ar—H), 7.42–7.45(m, 3H,Ph), 7.89–7.92 (m, 2H, Ph), 12.92 (br s, 1H, NH). 13C NMR(CDCl3, 75 MHz): δ 20.2, 63.7, 93.5, 114.8, 126.5, 127.0, 128.2, 130.7, 131.3, 140.1, 157.2, 163.1, 188.3. ESI-MS: 268(M+1)+. Analysis calculated for C17H17NO2: C 76.38, H 6.41, N 5.24; found: C 76.53, H 6.52, N 5.32. 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 = 0.93–0.96 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 (dashed lines) chains along the a axis.
(Z)-3-(4-Methoxyanilino)-1-phenylbut-2-en-1-one top
Crystal data top
C17H17NO2F(000) = 568
Mr = 267.32Dx = 1.229 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2333 reflections
a = 6.435 (2) Åθ = 2.6–26.3°
b = 7.287 (3) ŵ = 0.08 mm1
c = 30.919 (12) ÅT = 294 K
β = 94.954 (6)°Block, yellow
V = 1444.5 (9) Å30.24 × 0.20 × 0.16 mm
Z = 4
Data collection top
Bruker SMART CCD area-detector
diffractometer
2931 independent reflections
Radiation source: fine-focus sealed tube1900 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.036
ϕ and ω scansθmax = 26.4°, θmin = 1.3°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 48
Tmin = 0.739, Tmax = 1.000k = 97
7729 measured reflectionsl = 3438
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.046H-atom parameters constrained
wR(F2) = 0.135 w = 1/[σ2(Fo2) + (0.0645P)2 + 0.2627P]
where P = (Fo2 + 2Fc2)/3
S = 1.00(Δ/σ)max = 0.001
2931 reflectionsΔρmax = 0.18 e Å3
184 parametersΔρmin = 0.17 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.035 (3)
Crystal data top
C17H17NO2V = 1444.5 (9) Å3
Mr = 267.32Z = 4
Monoclinic, P21/nMo Kα radiation
a = 6.435 (2) ŵ = 0.08 mm1
b = 7.287 (3) ÅT = 294 K
c = 30.919 (12) Å0.24 × 0.20 × 0.16 mm
β = 94.954 (6)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
2931 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1900 reflections with I > 2σ(I)
Tmin = 0.739, Tmax = 1.000Rint = 0.036
7729 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0460 restraints
wR(F2) = 0.135H-atom parameters constrained
S = 1.00Δρmax = 0.18 e Å3
2931 reflectionsΔρmin = 0.17 e Å3
184 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
O10.0332 (2)0.1669 (2)0.45901 (4)0.0621 (4)
O20.17087 (19)0.1729 (2)0.20705 (4)0.0552 (4)
N10.0723 (2)0.1693 (2)0.27987 (4)0.0417 (4)
H10.04890.17220.26580.050*
C10.0705 (2)0.1739 (2)0.32573 (5)0.0364 (4)
C20.0759 (3)0.2824 (3)0.34338 (5)0.0412 (4)
H20.16390.35580.32530.049*
C30.0940 (3)0.2835 (3)0.38775 (5)0.0445 (5)
H30.19470.35600.39920.053*
C40.0378 (3)0.1768 (2)0.41473 (5)0.0423 (4)
C50.1869 (3)0.0706 (3)0.39734 (6)0.0515 (5)
H50.27800.00050.41560.062*
C60.2022 (3)0.0673 (3)0.35319 (6)0.0480 (5)
H60.30150.00690.34180.058*
C70.1412 (4)0.2438 (4)0.47712 (6)0.0798 (8)
H7A0.13850.37490.47400.120*
H7B0.13660.21260.50740.120*
H7C0.26700.19630.46230.120*
C80.4516 (3)0.1682 (3)0.27522 (6)0.0504 (5)
H8A0.45790.24290.30090.076*
H8B0.53990.21990.25490.076*
H8C0.49810.04630.28280.076*
C90.2316 (3)0.1612 (2)0.25509 (5)0.0384 (4)
C100.1947 (3)0.1546 (2)0.21040 (5)0.0397 (4)
H100.30870.14490.19400.048*
C110.0069 (3)0.1616 (2)0.18819 (5)0.0386 (4)
C120.0272 (3)0.1643 (2)0.13949 (5)0.0390 (4)
C130.1114 (3)0.0745 (3)0.11502 (5)0.0485 (5)
H130.22180.00860.12880.058*
C140.0869 (3)0.0820 (3)0.07020 (6)0.0592 (6)
H140.17970.01950.05400.071*
C150.0728 (4)0.1807 (3)0.04946 (6)0.0612 (6)
H150.08720.18690.01930.073*
C160.2117 (4)0.2703 (3)0.07320 (6)0.0621 (6)
H160.32030.33750.05910.075*
C170.1908 (3)0.2612 (3)0.11809 (6)0.0525 (5)
H170.28710.32050.13400.063*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0685 (10)0.0814 (11)0.0370 (7)0.0231 (8)0.0080 (6)0.0056 (7)
O20.0377 (7)0.0836 (11)0.0449 (7)0.0037 (7)0.0074 (6)0.0087 (7)
N10.0333 (8)0.0548 (10)0.0370 (8)0.0018 (7)0.0037 (6)0.0034 (7)
C10.0366 (9)0.0376 (10)0.0348 (9)0.0016 (7)0.0027 (7)0.0008 (7)
C20.0355 (9)0.0476 (11)0.0399 (10)0.0068 (8)0.0001 (7)0.0040 (8)
C30.0426 (10)0.0488 (12)0.0429 (10)0.0107 (8)0.0082 (8)0.0013 (8)
C40.0476 (10)0.0462 (11)0.0329 (9)0.0030 (8)0.0031 (8)0.0010 (8)
C50.0565 (12)0.0516 (12)0.0463 (11)0.0195 (10)0.0038 (9)0.0093 (9)
C60.0557 (11)0.0438 (11)0.0456 (11)0.0178 (9)0.0100 (8)0.0023 (9)
C70.0960 (18)0.102 (2)0.0442 (12)0.0378 (15)0.0206 (12)0.0024 (12)
C80.0375 (10)0.0637 (13)0.0498 (11)0.0002 (9)0.0039 (8)0.0037 (9)
C90.0368 (9)0.0355 (10)0.0434 (10)0.0023 (7)0.0066 (7)0.0012 (8)
C100.0372 (9)0.0442 (11)0.0388 (9)0.0009 (8)0.0098 (7)0.0003 (8)
C110.0404 (10)0.0363 (10)0.0398 (9)0.0036 (8)0.0082 (8)0.0024 (8)
C120.0424 (10)0.0361 (10)0.0384 (9)0.0062 (8)0.0023 (7)0.0024 (8)
C130.0552 (12)0.0484 (12)0.0425 (11)0.0028 (9)0.0071 (8)0.0012 (9)
C140.0729 (14)0.0622 (14)0.0439 (11)0.0019 (11)0.0137 (10)0.0078 (10)
C150.0862 (16)0.0605 (14)0.0358 (10)0.0136 (12)0.0008 (10)0.0006 (10)
C160.0730 (14)0.0571 (14)0.0526 (12)0.0022 (11)0.0148 (10)0.0031 (10)
C170.0555 (12)0.0505 (12)0.0505 (12)0.0040 (10)0.0016 (9)0.0073 (10)
Geometric parameters (Å, º) top
O1—C41.374 (2)C8—C91.497 (2)
O1—C71.413 (2)C8—H8A0.96
O2—C111.251 (2)C8—H8B0.96
N1—C91.333 (2)C8—H8C0.96
N1—C11.419 (2)C9—C101.383 (2)
N1—H10.86C10—C111.415 (2)
C1—C21.378 (2)C10—H100.93
C1—C61.385 (2)C11—C121.500 (2)
C2—C31.387 (2)C12—C131.383 (2)
C2—H20.93C12—C171.387 (3)
C3—C41.378 (2)C13—C141.382 (2)
C3—H30.93C13—H130.93
C4—C51.378 (2)C14—C151.368 (3)
C5—C61.377 (2)C14—H140.93
C5—H50.93C15—C161.370 (3)
C6—H60.93C15—H150.93
C7—H7A0.96C16—C171.385 (3)
C7—H7B0.96C16—H160.93
C7—H7C0.96C17—H170.93
C4—O1—C7117.43 (15)C9—C8—H8C109.5
C9—N1—C1130.43 (15)H8A—C8—H8C109.5
C9—N1—H1114.8H8B—C8—H8C109.5
C1—N1—H1114.8N1—C9—C10120.13 (16)
C2—C1—C6118.82 (15)N1—C9—C8120.40 (15)
C2—C1—N1118.30 (15)C10—C9—C8119.40 (15)
C6—C1—N1122.79 (15)C9—C10—C11123.68 (15)
C1—C2—C3120.92 (16)C9—C10—H10118.2
C1—C2—H2119.5C11—C10—H10118.2
C3—C2—H2119.5O2—C11—C10123.41 (16)
C4—C3—C2119.71 (16)O2—C11—C12117.59 (15)
C4—C3—H3120.1C10—C11—C12118.94 (14)
C2—C3—H3120.1C13—C12—C17118.60 (16)
O1—C4—C5115.81 (15)C13—C12—C11122.58 (16)
O1—C4—C3124.58 (16)C17—C12—C11118.82 (16)
C5—C4—C3119.61 (16)C14—C13—C12120.45 (18)
C6—C5—C4120.56 (17)C14—C13—H13119.8
C6—C5—H5119.7C12—C13—H13119.8
C4—C5—H5119.7C15—C14—C13120.44 (19)
C5—C6—C1120.36 (17)C15—C14—H14119.8
C5—C6—H6119.8C13—C14—H14119.8
C1—C6—H6119.8C14—C15—C16119.87 (18)
O1—C7—H7A109.5C14—C15—H15120.1
O1—C7—H7B109.5C16—C15—H15120.1
H7A—C7—H7B109.5C15—C16—C17120.2 (2)
O1—C7—H7C109.5C15—C16—H16119.9
H7A—C7—H7C109.5C17—C16—H16119.9
H7B—C7—H7C109.5C16—C17—C12120.42 (18)
C9—C8—H8A109.5C16—C17—H17119.8
C9—C8—H8B109.5C12—C17—H17119.8
H8A—C8—H8B109.5
C9—N1—C1—C2142.48 (19)N1—C9—C10—C112.1 (3)
C9—N1—C1—C640.9 (3)C8—C9—C10—C11175.06 (16)
C6—C1—C2—C30.9 (3)C9—C10—C11—O20.6 (3)
N1—C1—C2—C3175.86 (16)C9—C10—C11—C12176.46 (16)
C1—C2—C3—C40.9 (3)O2—C11—C12—C13149.89 (18)
C7—O1—C4—C5167.8 (2)C10—C11—C12—C1332.8 (2)
C7—O1—C4—C312.2 (3)O2—C11—C12—C1730.3 (2)
C2—C3—C4—O1179.76 (17)C10—C11—C12—C17146.95 (18)
C2—C3—C4—C50.3 (3)C17—C12—C13—C140.2 (3)
O1—C4—C5—C6178.64 (18)C11—C12—C13—C14179.60 (17)
C3—C4—C5—C61.4 (3)C12—C13—C14—C151.0 (3)
C4—C5—C6—C11.4 (3)C13—C14—C15—C161.1 (3)
C2—C1—C6—C50.2 (3)C14—C15—C16—C170.0 (3)
N1—C1—C6—C5176.83 (17)C15—C16—C17—C121.2 (3)
C1—N1—C9—C10178.77 (16)C13—C12—C17—C161.3 (3)
C1—N1—C9—C84.1 (3)C11—C12—C17—C16178.51 (17)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O20.861.912.629 (2)139
C8—H8B···O2i0.962.493.351 (3)148
C3—H3···Cg2ii0.932.843.712 (3)156
C13—H13···Cg1iii0.932.823.619 (3)145
Symmetry codes: (i) x+1, y, z; (ii) x1/2, y+1/2, z+1/2; (iii) x+1/2, y1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC17H17NO2
Mr267.32
Crystal system, space groupMonoclinic, P21/n
Temperature (K)294
a, b, c (Å)6.435 (2), 7.287 (3), 30.919 (12)
β (°) 94.954 (6)
V3)1444.5 (9)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.24 × 0.20 × 0.16
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.739, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
7729, 2931, 1900
Rint0.036
(sin θ/λ)max1)0.626
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.046, 0.135, 1.00
No. of reflections2931
No. of parameters184
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.18, 0.17

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···O20.861.912.629 (2)139
C8—H8B···O2i0.962.493.351 (3)148
C3—H3···Cg2ii0.932.843.712 (3)156
C13—H13···Cg1iii0.932.823.619 (3)145
Symmetry codes: (i) x+1, y, z; (ii) x1/2, y+1/2, z+1/2; (iii) x+1/2, y1/2, z+1/2.
 

Acknowledgements

This work was supported financially by Jiangnan University.

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