organic compounds
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
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); 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
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2005); cell SAINT-Plus (Bruker, 2004); data reduction: SAINT-Plus; 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).
Supporting information
https://doi.org/10.1107/S1600536810043680/is2620sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810043680/is2620Isup2.hkl
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.
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.
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 ~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)°.
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 (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).
Data collection: APEX2 (Bruker, 2005); cell
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).Fig. 1. Molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability displacement level. |
C12H15NO | F(000) = 408 |
Mr = 189.25 | Dx = 1.214 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 8475 reflections |
a = 10.0736 (2) Å | θ = 2.9–28.3° |
b = 10.8800 (2) Å | µ = 0.08 mm−1 |
c = 10.0723 (2) Å | T = 100 K |
β = 110.291 (1)° | Cuboid, white |
V = 1035.43 (3) Å3 | 0.34 × 0.31 × 0.2 mm |
Z = 4 |
Bruker X8 APEXII 4K Kappa CCD diffractometer | 2257 independent reflections |
Radiation source: fine-focus sealed tube | 2011 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.024 |
ω and φ scans | θmax = 27°, θmin = 1.6° |
Absorption correction: multi-scan (SADABS; Bruker, 2004) | h = −9→12 |
Tmin = 0.974, Tmax = 0.985 | k = −13→13 |
17880 measured reflections | l = −12→12 |
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)] = 0.035 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.099 | H 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 parameters | Δρmax = 0.28 e Å−3 |
0 restraints | Δρmin = −0.20 e Å−3 |
C12H15NO | V = 1035.43 (3) Å3 |
Mr = 189.25 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 10.0736 (2) Å | µ = 0.08 mm−1 |
b = 10.8800 (2) Å | T = 100 K |
c = 10.0723 (2) Å | 0.34 × 0.31 × 0.2 mm |
β = 110.291 (1)° |
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 = 0.985 | Rint = 0.024 |
17880 measured reflections |
R[F2 > 2σ(F2)] = 0.035 | 0 restraints |
wR(F2) = 0.099 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | Δρmax = 0.28 e Å−3 |
2257 reflections | Δρmin = −0.20 e Å−3 |
134 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
H11 | 0.4680 (15) | 0.6492 (15) | 0.1245 (16) | 0.035 (4)* | |
C1 | 0.40618 (11) | 0.93113 (10) | 0.19271 (12) | 0.0217 (2) | |
H1A | 0.3029 | 0.923 | 0.1547 | 0.033* | |
H1B | 0.4343 | 1.0054 | 0.1542 | 0.033* | |
H1C | 0.4381 | 0.9371 | 0.2961 | 0.033* | |
C2 | 0.47215 (10) | 0.82105 (9) | 0.15165 (10) | 0.0172 (2) | |
C3 | 0.58328 (10) | 0.83668 (10) | 0.10224 (11) | 0.0184 (2) | |
H3 | 0.6177 | 0.9177 | 0.1004 | 0.022* | |
C4 | 0.64936 (10) | 0.73921 (10) | 0.05403 (11) | 0.0189 (2) | |
C5 | 0.76886 (11) | 0.77128 (11) | 0.00155 (12) | 0.0237 (2) | |
H5A | 0.8532 | 0.7236 | 0.0543 | 0.036* | |
H5B | 0.7901 | 0.8592 | 0.0158 | 0.036* | |
H5C | 0.7407 | 0.7518 | −0.0995 | 0.036* | |
C111 | 0.30726 (10) | 0.66767 (9) | 0.19824 (11) | 0.0168 (2) | |
C112 | 0.26693 (11) | 0.72321 (10) | 0.30296 (11) | 0.0199 (2) | |
H112 | 0.3174 | 0.7925 | 0.3529 | 0.024* | |
C113 | 0.15224 (11) | 0.67660 (10) | 0.33410 (11) | 0.0213 (2) | |
H113 | 0.1239 | 0.7164 | 0.4039 | 0.026* | |
C114 | 0.07814 (10) | 0.57364 (10) | 0.26603 (11) | 0.0197 (2) | |
C115 | 0.12396 (11) | 0.51612 (10) | 0.16576 (11) | 0.0206 (2) | |
H115 | 0.0773 | 0.4437 | 0.1203 | 0.025* | |
C116 | 0.23603 (11) | 0.56237 (10) | 0.13106 (11) | 0.0194 (2) | |
H116 | 0.2644 | 0.5223 | 0.0614 | 0.023* | |
C117 | −0.04840 (11) | 0.52533 (11) | 0.29731 (13) | 0.0257 (3) | |
H11A | −0.0518 | 0.5634 | 0.3843 | 0.039* | |
H11B | −0.0404 | 0.436 | 0.3095 | 0.039* | |
H11C | −0.1351 | 0.5453 | 0.2184 | 0.039* | |
N11 | 0.42309 (9) | 0.70705 (8) | 0.15977 (9) | 0.0176 (2) | |
O12 | 0.61277 (8) | 0.62890 (7) | 0.05166 (8) | 0.0227 (2) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0245 (5) | 0.0165 (5) | 0.0269 (5) | 0.0011 (4) | 0.0124 (4) | −0.0005 (4) |
C2 | 0.0182 (5) | 0.0165 (5) | 0.0155 (5) | 0.0009 (4) | 0.0042 (4) | 0.0003 (4) |
C3 | 0.0191 (5) | 0.0164 (5) | 0.0196 (5) | −0.0013 (4) | 0.0068 (4) | 0.0002 (4) |
C4 | 0.0174 (5) | 0.0206 (5) | 0.0185 (5) | 0.0000 (4) | 0.0059 (4) | 0.0013 (4) |
C5 | 0.0212 (5) | 0.0240 (6) | 0.0292 (6) | −0.0016 (4) | 0.0127 (4) | 0.0002 (4) |
C111 | 0.0156 (4) | 0.0167 (5) | 0.0182 (5) | 0.0028 (4) | 0.0061 (4) | 0.0035 (4) |
C112 | 0.0216 (5) | 0.0191 (5) | 0.0191 (5) | −0.0010 (4) | 0.0073 (4) | −0.0016 (4) |
C113 | 0.0224 (5) | 0.0238 (6) | 0.0207 (5) | 0.0029 (4) | 0.0114 (4) | 0.0000 (4) |
C114 | 0.0162 (5) | 0.0215 (5) | 0.0216 (5) | 0.0032 (4) | 0.0069 (4) | 0.0048 (4) |
C115 | 0.0193 (5) | 0.0188 (5) | 0.0229 (5) | −0.0012 (4) | 0.0062 (4) | −0.0006 (4) |
C116 | 0.0205 (5) | 0.0189 (5) | 0.0200 (5) | 0.0024 (4) | 0.0087 (4) | −0.0005 (4) |
C117 | 0.0200 (5) | 0.0289 (6) | 0.0313 (6) | 0.0002 (4) | 0.0129 (4) | 0.0035 (5) |
N11 | 0.0182 (4) | 0.0156 (4) | 0.0214 (4) | 0.0016 (3) | 0.0100 (3) | 0.0002 (3) |
O12 | 0.0245 (4) | 0.0171 (4) | 0.0306 (4) | 0.0000 (3) | 0.0145 (3) | −0.0006 (3) |
C1—C2 | 1.4959 (14) | C111—N11 | 1.4173 (13) |
C1—H1A | 0.98 | C112—C113 | 1.3934 (14) |
C1—H1B | 0.98 | C112—H112 | 0.95 |
C1—H1C | 0.98 | C113—C114 | 1.3882 (16) |
C2—N11 | 1.3482 (13) | C113—H113 | 0.95 |
C2—C3 | 1.3842 (14) | C114—C115 | 1.3957 (15) |
C3—C4 | 1.4240 (15) | C114—C117 | 1.5097 (14) |
C3—H3 | 0.95 | C115—C116 | 1.3870 (14) |
C4—O12 | 1.2533 (13) | C115—H115 | 0.95 |
C4—C5 | 1.5138 (14) | C116—H116 | 0.95 |
C5—H5A | 0.98 | C117—H11A | 0.98 |
C5—H5B | 0.98 | C117—H11B | 0.98 |
C5—H5C | 0.98 | C117—H11C | 0.98 |
C111—C112 | 1.3929 (14) | N11—H11 | 0.916 (16) |
C111—C116 | 1.3958 (15) | ||
C2—C1—H1A | 109.5 | C111—C112—C113 | 119.66 (10) |
C2—C1—H1B | 109.5 | C111—C112—H112 | 120.2 |
H1A—C1—H1B | 109.5 | C113—C112—H112 | 120.2 |
C2—C1—H1C | 109.5 | C114—C113—C112 | 121.89 (10) |
H1A—C1—H1C | 109.5 | C114—C113—H113 | 119.1 |
H1B—C1—H1C | 109.5 | C112—C113—H113 | 119.1 |
N11—C2—C3 | 119.61 (9) | C113—C114—C115 | 117.59 (9) |
N11—C2—C1 | 120.83 (9) | C113—C114—C117 | 121.75 (10) |
C3—C2—C1 | 119.56 (9) | C115—C114—C117 | 120.66 (10) |
C2—C3—C4 | 124.27 (10) | C116—C115—C114 | 121.46 (10) |
C2—C3—H3 | 117.9 | C116—C115—H115 | 119.3 |
C4—C3—H3 | 117.9 | C114—C115—H115 | 119.3 |
O12—C4—C3 | 123.40 (9) | C115—C116—C111 | 120.14 (10) |
O12—C4—C5 | 118.58 (9) | C115—C116—H116 | 119.9 |
C3—C4—C5 | 118.02 (9) | C111—C116—H116 | 119.9 |
C4—C5—H5A | 109.5 | C114—C117—H11A | 109.5 |
C4—C5—H5B | 109.5 | C114—C117—H11B | 109.5 |
H5A—C5—H5B | 109.5 | H11A—C117—H11B | 109.5 |
C4—C5—H5C | 109.5 | C114—C117—H11C | 109.5 |
H5A—C5—H5C | 109.5 | H11A—C117—H11C | 109.5 |
H5B—C5—H5C | 109.5 | H11B—C117—H11C | 109.5 |
C112—C111—C116 | 119.16 (9) | C2—N11—C111 | 130.44 (9) |
C112—C111—N11 | 124.05 (9) | C2—N11—H11 | 111.6 (9) |
C116—C111—N11 | 116.69 (9) | C111—N11—H11 | 117.5 (9) |
N11—C2—C3—C4 | 1.92 (15) | C113—C114—C115—C116 | −2.38 (16) |
C1—C2—C3—C4 | −176.91 (9) | C117—C114—C115—C116 | 177.08 (10) |
C2—C3—C4—O12 | 0.03 (16) | C114—C115—C116—C111 | 0.96 (16) |
C2—C3—C4—C5 | 179.34 (9) | C112—C111—C116—C115 | 1.83 (15) |
C116—C111—C112—C113 | −3.10 (15) | N11—C111—C116—C115 | 178.26 (9) |
N11—C111—C112—C113 | −179.26 (9) | C3—C2—N11—C111 | −175.93 (9) |
C111—C112—C113—C114 | 1.67 (16) | C1—C2—N11—C111 | 2.88 (16) |
C112—C113—C114—C115 | 1.06 (16) | C112—C111—N11—C2 | −36.50 (16) |
C112—C113—C114—C117 | −178.39 (10) | C116—C111—N11—C2 | 147.26 (10) |
D—H···A | D—H | H···A | D···A | 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. |
Experimental details
Crystal data | |
Chemical formula | C12H15NO |
Mr | 189.25 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 100 |
a, b, c (Å) | 10.0736 (2), 10.8800 (2), 10.0723 (2) |
β (°) | 110.291 (1) |
V (Å3) | 1035.43 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.34 × 0.31 × 0.2 |
Data collection | |
Diffractometer | Bruker X8 APEXII 4K Kappa CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2004) |
Tmin, Tmax | 0.974, 0.985 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 17880, 2257, 2011 |
Rint | 0.024 |
(sin θ/λ)max (Å−1) | 0.639 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.035, 0.099, 1.05 |
No. of reflections | 2257 |
No. of parameters | 134 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 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).
D—H···A | D—H | H···A | D···A | D—H···A |
C116—H116···O12i | 0.95 | 2.55 | 3.462 (1) | 160.4 |
N11—H11···O12 | 0.916 (16) | 1.859 (16) | 2.6463 (13) | 142.7 (15) |
Symmetry code: (i) −x+1, −y+1, −z. |
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-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.
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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)°.