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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 66| Part 11| November 2010| Pages o3011-o3012

4-[(4-Methyl­phen­yl)amino]­pent-3-en-2-one

aDepartment of Chemistry, University of the Free State, PO Box 339, Bloemfontein 9300, South Africa
*Correspondence e-mail: truidie@hotmail.com

(Received 22 October 2010; accepted 26 October 2010; online 31 October 2010)

The title enamino­ketone, C12H15NO, is a derivative of 4-(phenyl­amino)­pent-3-en-2-one with an approximately planar pentenone backbone, the greatest displacement from the plane being 0.042 (1) Å; the asymmetry in C—C distances in the group suggests the presence of unsaturated bonds. The dihedral angle between the benzene ring and the pentenone plane is 29.90 (4)°. In the crystal, an intra­molecular N—H⋯O inter­action and an inter­molecular C—H⋯O hydrogen bond are observed.

Related literature

For synthetic background, see: Shaheen et al. (2006[Shaheen, F., Marchio, L., Badshah, A. & Khosa, M. K. (2006). Acta Cryst. E62, o873-o874.]); Venter et al. (2010[Venter, G. J. S., Steyl, G. & Roodt, A. (2010). Acta Cryst. E66, o1593-o1594.]). For applications of enamino­ketones, see: Brink et al. (2010[Brink, A., Visser, H. G., Steyl, G. & Roodt, A. (2010). Dalton Trans. pp. 5572-5578.]); Chen & Rhodes (1996[Chen, H. & Rhodes, J. (1996). J. Mol. Med. 74, 497-504.]); Pyżuk et al. (1993[Pyżuk, W., Krówczynsk, A. & Górecka, E. (1993). Mol. Cryst. Liq. Cryst. 237, 75-84.]); Roodt & Steyn (2000[Roodt, A. & Steyn, G. J. J. (2000). Recent Research Developments in Inorganic Chemistry, Vol. 2, pp. 1-23. Trivandrum: Transworld Research Network.]); Tan et al. (2008[Tan, H. Y., Loke, W. K., Tan, Y. T. & Nguyen, N.-T. (2008). Lab. Chip, 8, 885-891.]); Xia et al. (2008[Xia, M., Wu, B. & Xiang, G. (2008). J. Fluorine Chem. 129, 402-408.]). For structures of related ligand systems, see: Venter et al. (2009a[Venter, G. J. S., Steyl, G. & Roodt, A. (2009a). Acta Cryst. E65, m1321-m1322.],b[Venter, G. J. S., Steyl, G. & Roodt, A. (2009b). Acta Cryst. E65, m1606-m1607.]).

[Scheme 1]

Experimental

Crystal data
  • C12H15NO

  • Mr = 189.25

  • Monoclinic, P 21 /c

  • a = 10.0736 (2) Å

  • b = 10.8800 (2) Å

  • c = 10.0723 (2) Å

  • β = 110.291 (1)°

  • V = 1035.43 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 100 K

  • 0.34 × 0.31 × 0.2 mm

Data collection
  • Bruker X8 APEXII 4K Kappa CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2004[Bruker (2004). SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.974, Tmax = 0.985

  • 17880 measured reflections

  • 2257 independent reflections

  • 2011 reflections with I > 2σ(I)

  • Rint = 0.024

Refinement
  • R[F2 > 2σ(F2)] = 0.035

  • wR(F2) = 0.099

  • S = 1.05

  • 2257 reflections

  • 134 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.28 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C116—H116⋯O12i 0.95 2.55 3.462 (1) 160
N11—H11⋯O12 0.916 (16) 1.859 (16) 2.6463 (13) 142.7 (15)
Symmetry code: (i) -x+1, -y+1, -z.

Table 2
Comparative geometric parameters (Å, °) for free and coordinated N,O-bidendate (N,O-bid) compounds

Parameter I II III IV
N11—C111 1.417 (2) 1.422 (2) 1.521 (4)/1.463 (3) 1.440 (4)
N11—C2 1.348 (1) 1.345 (2) 1.320 (4) 1.319 (4)
O12—C4 1.253 (1) 1.257 (2) 1.290 (3) 1.291 (4)
C2—C3 1.384 (2) 1.383 (3) 1.410 (4) 1.423 (4)
C3—C4 1.424 (2) 1.420 (2) 1.365 (3) 1.382 (3)
N11⋯O12 2.646 (1) 2.635 (2) 2.885 (3) 2.886 (3)
N11—C2—C4—O12 1.70 (9) −0.5 (1) 4.1 (2) −2.6 (2)
Dihedral angle 29.90 (3) 49.53 (5) 87.47 (4)/89.36 (8) 85.58 (8)
(I) This work. (II) Uncoordinated 4-(2-methyl­phenyl­amino)­pent-3-en-2-one (Venter et al., 2010[Venter, G. J. S., Steyl, G. & Roodt, A. (2010). Acta Cryst. E66, o1593-o1594.]). (III) N,O-bid = 4-(2,3-dimethyl­phenyl­amino)­pent-3-en-2-onato (Venter et al., 2009a[Venter, G. J. S., Steyl, G. & Roodt, A. (2009a). Acta Cryst. E65, m1321-m1322.]). (IV) N,O-bid = 4-(2,6-dimethyl­phenyl­amino)­pent-3-en-2-onato (Venter et al., 2009b[Venter, G. J. S., Steyl, G. & Roodt, A. (2009b). Acta Cryst. E65, m1606-m1607.]). The dihedral angle is defined as the torsion angle between the N—C—C—C—O plane and the phenyl ring.

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-Plus (Bruker, 2004[Bruker (2004). SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-Plus; 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: DIAMOND (Brandenburg & Putz, 2005[Brandenburg, K. & Putz, H. (2005). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

A well known system in organometallic chemistry is the β-diketone compound AcacH (acetylacetone; or when coordinated acetylacetonato, acac-). A multitude of derivatives have been synthesized to date, with enaminoketones being one type. Since enaminoketones contain N and O atoms as well as an unsaturated C—C bond, these electron-rich compounds are of interest in various fields including liquid crystals (Pyżuk et al., 1993), fluorescence studies (Xia et al., 2008) as well as formation of complexes of medical interest (Tan et al., 2008; Chen & Rhodes, 1996). It also has significant application possibilities in catalysis (Roodt & Steyn, 2000; Brink et al., 2010).

The title compound (Fig. 1) crystallizes in the monoclinic space group P21/c with Z = 4. This enaminoketone is a derivative of 4-(phenylamino)pent-3-en-2-one (PhonyH; Shaheen et al., 2006). Bond distances differ significantly from compounds coordinated to rhodium (Table 2; Venter et al., 2009a,b), such as the distance, N1···O1, greatly increasing (~0.2 Å) upon coordination to the metal. Similarities in bond parameters to other uncoordinated enaminoketone compounds (Venter et al., 2010) were observed. The C2—C3 distance of 1.385 (2) Å, versus the C3—C4 bond distance of 1.424 (2) Å indicates an unsaturated bond in the pentenone backbone. The dihedral angle between the benzene ring and the pentenone plane is 29.90 (4)°.

Related literature top

For synthetic background, see: Shaheen et al. (2006); Venter et al. (2010). For applications of enaminoketones, see: Brink et al. (2010); Chen & Rhodes (1996); Pyżuk et al. (1993); Roodt & Steyn (2000); Tan et al. (2008); Xia et al. (2008). For structures of related ligand systems, see: Venter et al. (2009a,b).

Experimental top

A solution of acetylacetone (11.02 g, 0.1101 mol), 4-Me-aniline (10.83 g, 0.1010 mol) and 2 drops of H2SO4 (conc.) in 150 ml benzene was refluxed for 24 h in a Dean–Stark trap, filtered and left to crystallize. Crystals suitable for X-ray diffraction were obtained in 16.95 g (88.67%) yield. This compound is stable in air and light over a period of several months.

Refinement top

The methyl and aromatic H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms, with C—H = 0.95 and 0.98 Å and Uiso(H) = 1.5Ueq(C) and 1.2Ueq(C), respectively. The methyl groups were generated to fit the difference electron density and the groups were then refined as rigid rotors. The highest residual electron-density peak is 0.74 Å from C5.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability displacement level.
4-(4-Methylanilino)pent-3-en-2-one top
Crystal data top
C12H15NOF(000) = 408
Mr = 189.25Dx = 1.214 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 8475 reflections
a = 10.0736 (2) Åθ = 2.9–28.3°
b = 10.8800 (2) ŵ = 0.08 mm1
c = 10.0723 (2) ÅT = 100 K
β = 110.291 (1)°Cuboid, white
V = 1035.43 (3) Å30.34 × 0.31 × 0.2 mm
Z = 4
Data collection top
Bruker X8 APEXII 4K Kappa CCD
diffractometer
2257 independent reflections
Radiation source: fine-focus sealed tube2011 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
ω and ϕ scansθmax = 27°, θmin = 1.6°
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
h = 912
Tmin = 0.974, Tmax = 0.985k = 1313
17880 measured reflectionsl = 1212
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)] = 0.035Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.099H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.0527P)2 + 0.3154P]
where P = (Fo2 + 2Fc2)/3
2257 reflections(Δ/σ)max = 0.001
134 parametersΔρmax = 0.28 e Å3
0 restraintsΔρmin = 0.20 e Å3
Crystal data top
C12H15NOV = 1035.43 (3) Å3
Mr = 189.25Z = 4
Monoclinic, P21/cMo Kα radiation
a = 10.0736 (2) ŵ = 0.08 mm1
b = 10.8800 (2) ÅT = 100 K
c = 10.0723 (2) Å0.34 × 0.31 × 0.2 mm
β = 110.291 (1)°
Data collection top
Bruker X8 APEXII 4K Kappa CCD
diffractometer
2257 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
2011 reflections with I > 2σ(I)
Tmin = 0.974, Tmax = 0.985Rint = 0.024
17880 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0350 restraints
wR(F2) = 0.099H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.28 e Å3
2257 reflectionsΔρmin = 0.20 e Å3
134 parameters
Special details top

Experimental. The intensity data was collected on a Bruker X8 ApexII 4 K Kappa CCD diffractometer using an exposure time of 30 s/frame. A total of 688 frames were collected with a frame width of 0.5° covering up to θ = 27.00° with 99.9% completeness accomplished.

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
H110.4680 (15)0.6492 (15)0.1245 (16)0.035 (4)*
C10.40618 (11)0.93113 (10)0.19271 (12)0.0217 (2)
H1A0.30290.9230.15470.033*
H1B0.43431.00540.15420.033*
H1C0.43810.93710.29610.033*
C20.47215 (10)0.82105 (9)0.15165 (10)0.0172 (2)
C30.58328 (10)0.83668 (10)0.10224 (11)0.0184 (2)
H30.61770.91770.10040.022*
C40.64936 (10)0.73921 (10)0.05403 (11)0.0189 (2)
C50.76886 (11)0.77128 (11)0.00155 (12)0.0237 (2)
H5A0.85320.72360.05430.036*
H5B0.79010.85920.01580.036*
H5C0.74070.75180.09950.036*
C1110.30726 (10)0.66767 (9)0.19824 (11)0.0168 (2)
C1120.26693 (11)0.72321 (10)0.30296 (11)0.0199 (2)
H1120.31740.79250.35290.024*
C1130.15224 (11)0.67660 (10)0.33410 (11)0.0213 (2)
H1130.12390.71640.40390.026*
C1140.07814 (10)0.57364 (10)0.26603 (11)0.0197 (2)
C1150.12396 (11)0.51612 (10)0.16576 (11)0.0206 (2)
H1150.07730.44370.12030.025*
C1160.23603 (11)0.56237 (10)0.13106 (11)0.0194 (2)
H1160.26440.52230.06140.023*
C1170.04840 (11)0.52533 (11)0.29731 (13)0.0257 (3)
H11A0.05180.56340.38430.039*
H11B0.04040.4360.30950.039*
H11C0.13510.54530.21840.039*
N110.42309 (9)0.70705 (8)0.15977 (9)0.0176 (2)
O120.61277 (8)0.62890 (7)0.05166 (8)0.0227 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0245 (5)0.0165 (5)0.0269 (5)0.0011 (4)0.0124 (4)0.0005 (4)
C20.0182 (5)0.0165 (5)0.0155 (5)0.0009 (4)0.0042 (4)0.0003 (4)
C30.0191 (5)0.0164 (5)0.0196 (5)0.0013 (4)0.0068 (4)0.0002 (4)
C40.0174 (5)0.0206 (5)0.0185 (5)0.0000 (4)0.0059 (4)0.0013 (4)
C50.0212 (5)0.0240 (6)0.0292 (6)0.0016 (4)0.0127 (4)0.0002 (4)
C1110.0156 (4)0.0167 (5)0.0182 (5)0.0028 (4)0.0061 (4)0.0035 (4)
C1120.0216 (5)0.0191 (5)0.0191 (5)0.0010 (4)0.0073 (4)0.0016 (4)
C1130.0224 (5)0.0238 (6)0.0207 (5)0.0029 (4)0.0114 (4)0.0000 (4)
C1140.0162 (5)0.0215 (5)0.0216 (5)0.0032 (4)0.0069 (4)0.0048 (4)
C1150.0193 (5)0.0188 (5)0.0229 (5)0.0012 (4)0.0062 (4)0.0006 (4)
C1160.0205 (5)0.0189 (5)0.0200 (5)0.0024 (4)0.0087 (4)0.0005 (4)
C1170.0200 (5)0.0289 (6)0.0313 (6)0.0002 (4)0.0129 (4)0.0035 (5)
N110.0182 (4)0.0156 (4)0.0214 (4)0.0016 (3)0.0100 (3)0.0002 (3)
O120.0245 (4)0.0171 (4)0.0306 (4)0.0000 (3)0.0145 (3)0.0006 (3)
Geometric parameters (Å, º) top
C1—C21.4959 (14)C111—N111.4173 (13)
C1—H1A0.98C112—C1131.3934 (14)
C1—H1B0.98C112—H1120.95
C1—H1C0.98C113—C1141.3882 (16)
C2—N111.3482 (13)C113—H1130.95
C2—C31.3842 (14)C114—C1151.3957 (15)
C3—C41.4240 (15)C114—C1171.5097 (14)
C3—H30.95C115—C1161.3870 (14)
C4—O121.2533 (13)C115—H1150.95
C4—C51.5138 (14)C116—H1160.95
C5—H5A0.98C117—H11A0.98
C5—H5B0.98C117—H11B0.98
C5—H5C0.98C117—H11C0.98
C111—C1121.3929 (14)N11—H110.916 (16)
C111—C1161.3958 (15)
C2—C1—H1A109.5C111—C112—C113119.66 (10)
C2—C1—H1B109.5C111—C112—H112120.2
H1A—C1—H1B109.5C113—C112—H112120.2
C2—C1—H1C109.5C114—C113—C112121.89 (10)
H1A—C1—H1C109.5C114—C113—H113119.1
H1B—C1—H1C109.5C112—C113—H113119.1
N11—C2—C3119.61 (9)C113—C114—C115117.59 (9)
N11—C2—C1120.83 (9)C113—C114—C117121.75 (10)
C3—C2—C1119.56 (9)C115—C114—C117120.66 (10)
C2—C3—C4124.27 (10)C116—C115—C114121.46 (10)
C2—C3—H3117.9C116—C115—H115119.3
C4—C3—H3117.9C114—C115—H115119.3
O12—C4—C3123.40 (9)C115—C116—C111120.14 (10)
O12—C4—C5118.58 (9)C115—C116—H116119.9
C3—C4—C5118.02 (9)C111—C116—H116119.9
C4—C5—H5A109.5C114—C117—H11A109.5
C4—C5—H5B109.5C114—C117—H11B109.5
H5A—C5—H5B109.5H11A—C117—H11B109.5
C4—C5—H5C109.5C114—C117—H11C109.5
H5A—C5—H5C109.5H11A—C117—H11C109.5
H5B—C5—H5C109.5H11B—C117—H11C109.5
C112—C111—C116119.16 (9)C2—N11—C111130.44 (9)
C112—C111—N11124.05 (9)C2—N11—H11111.6 (9)
C116—C111—N11116.69 (9)C111—N11—H11117.5 (9)
N11—C2—C3—C41.92 (15)C113—C114—C115—C1162.38 (16)
C1—C2—C3—C4176.91 (9)C117—C114—C115—C116177.08 (10)
C2—C3—C4—O120.03 (16)C114—C115—C116—C1110.96 (16)
C2—C3—C4—C5179.34 (9)C112—C111—C116—C1151.83 (15)
C116—C111—C112—C1133.10 (15)N11—C111—C116—C115178.26 (9)
N11—C111—C112—C113179.26 (9)C3—C2—N11—C111175.93 (9)
C111—C112—C113—C1141.67 (16)C1—C2—N11—C1112.88 (16)
C112—C113—C114—C1151.06 (16)C112—C111—N11—C236.50 (16)
C112—C113—C114—C117178.39 (10)C116—C111—N11—C2147.26 (10)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C116—H116···O12i0.952.553.462 (1)160
N11—H11···O120.916 (16)1.859 (16)2.6463 (13)142.7 (15)
Symmetry code: (i) x+1, y+1, z.

Experimental details

Crystal data
Chemical formulaC12H15NO
Mr189.25
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)10.0736 (2), 10.8800 (2), 10.0723 (2)
β (°) 110.291 (1)
V3)1035.43 (3)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.34 × 0.31 × 0.2
Data collection
DiffractometerBruker X8 APEXII 4K Kappa CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2004)
Tmin, Tmax0.974, 0.985
No. of measured, independent and
observed [I > 2σ(I)] reflections
17880, 2257, 2011
Rint0.024
(sin θ/λ)max1)0.639
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.035, 0.099, 1.05
No. of reflections2257
No. of parameters134
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.28, 0.20

Computer programs: APEX2 (Bruker, 2005), SAINT-Plus (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg & Putz, 2005), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C116—H116···O12i0.952.553.462 (1)160.4
N11—H11···O120.916 (16)1.859 (16)2.6463 (13)142.7 (15)
Symmetry code: (i) x+1, y+1, z.
Comparative geometric parameters (Å, °) for free and coordinated N,O-bidendate (N,O-bid) compounds top
ParameterIIIIIIIV
N11—C1111.417 (2)1.422 (2)1.521 (4)/1.463 (3)1.440 (4)
N11—C21.348 (1)1.345 (2)1.320 (4)1.319 (4)
O12—C41.253 (1)1.257 (2)1.290 (3)1.291 (4)
C2—C31.384 (2)1.383 (3)1.410 (4)1.423 (4)
C3—C41.424 (2)1.420 (2)1.365 (3)1.382 (3)
N11···O122.646 (1)2.635 (2)2.885 (3)2.886 (3)
N11—C2—C4—O121.70 (9)-0.5 (1)4.1 (2)-2.6 (2)
Dihedral angle29.90 (3)49.53 (5)87.47 (4)/89.36 (8)85.58 (8)
(I) This work. (II) Uncoordinated 4-(2-methylphenylamino)pent-3-en-2-onato (Venter et al., 2010). (III) N,O-bid = 4-(2,3-dimethylphenylamino)pent-3-en-2-onato (Venter et al., 2009a). (IV) N,O-bid = 4-(2,6-dimethylphenylamino)pent-3-en-2-onato (Venter et al., 2009b). The dihedral angle is defined as the torsion angle between the N—C—C—C—O plane and the phenyl ring. A positive angle denotes a clockwise rotation.
 

Acknowledgements

Financial assistance from the University of the Free State is gratefully acknowledged. The authors also express their gratitude to SASOL and the South African National Research Foundation (SA-NRF/THRIP) for financial support of this project. Part of this material is based on work supported by the SA-NRF/THRIP under grant No. GUN 2068915. Opinions, findings, conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the SA-NRF.

References

First citationBrandenburg, K. & Putz, H. (2005). DIAMOND. Crystal Impact GbR, Bonn, Germany.
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Volume 66| Part 11| November 2010| Pages o3011-o3012
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