organic compounds
N-[4-(Dimethylamino)benzylidene]-4-methylaniline
aCentre for Crystal Growth, School of Advanced Sciences, VIT University, Vellore 632 014, India, bSophisticated Test and Instrumentation Centre (STIC), Cochin University PO, Cochin 682 022, Kerala, and cDepartment of Physics, Bangladesh University of Engineering and Technology, Dhaka 1000, Bangladesh
*Correspondence e-mail: jpodder59@gmail.com
The molecules of the title compound, C16H18N2, exists in a trans conformation with respect to the C=N bond [1.270 (3) Å]. The least-squares plane of the dimethylamino group makes a dihedral angle of 1.3 (2)° with the ring to which it is attached. The dihedral angle between the two aromatic rings is 11.70 (2)°. The features weak C—H⋯π interactions.
Related literature
For the uses and biological importance of diketones, see: Xia et al. (2009); Shah et al. (1992); Ünver et al. (2004). For related structures, see: Fun et al. (2011); Khalaji & Simpson (2009).
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2004); cell APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009).
Supporting information
10.1107/S160053681301249X/bt6904sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S160053681301249X/bt6904Isup2.hkl
Supporting information file. DOI: 10.1107/S160053681301249X/bt6904Isup3.cml
The title compound was synthesized by the reaction of p-dimethylaminobenzaldehyde (10 mmol, 1.14919 g) with p-toluidine (10 mmol, 1.0717 g) in ethanol (25 ml) under reflux condition for six hours. After filtering, drying the solid product was recrystallized from ethanol/THF (5:1 v/v). After five days yellow colour crystals were obtained Which were suitable for X-ray diffraction studies.
The positions of hydrogen atoms were localized from the difference electron density maps and their distances were geometrically constrained. The H atoms bound to the C atoms were treated as riding atoms, with d(C–H) = 0.93 Å and Uiso(H) = 1.2Ueq(C) for aryl atoms; d(C–H) = 0.96 Å and Uiso(H) = 1.5Ueq(C) for methyl group. The methyl groups were allowed to rotate but not to tip.
Data collection: APEX2 (Bruker, 2004); cell
APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).C16H18N2 | F(000) = 1024 |
Mr = 238.32 | Dx = 1.152 Mg m−3 |
Orthorhombic, Pbca | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2ab | Cell parameters from 1737 reflections |
a = 10.4814 (10) Å | θ = 2.3–26.0° |
b = 8.0528 (8) Å | µ = 0.07 mm−1 |
c = 32.571 (3) Å | T = 296 K |
V = 2749.1 (4) Å3 | Block, yellow |
Z = 8 | 0.30 × 0.25 × 0.20 mm |
Bruker Kappa APEXII CCD diffractometer | 2692 independent reflections |
Radiation source: fine-focus sealed tube | 1737 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.041 |
ω and ϕ scan | θmax = 26.0°, θmin = 2.3° |
Absorption correction: multi-scan (SADABS; Bruker, 2004) | h = −12→12 |
Tmin = 0.980, Tmax = 0.987 | k = −9→7 |
17121 measured reflections | l = −40→40 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.061 | H-atom parameters constrained |
wR(F2) = 0.187 | w = 1/[σ2(Fo2) + (0.0814P)2 + 0.8121P] where P = (Fo2 + 2Fc2)/3 |
S = 1.08 | (Δ/σ)max = 0.001 |
2692 reflections | Δρmax = 0.21 e Å−3 |
167 parameters | Δρmin = −0.16 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0130 (19) |
C16H18N2 | V = 2749.1 (4) Å3 |
Mr = 238.32 | Z = 8 |
Orthorhombic, Pbca | Mo Kα radiation |
a = 10.4814 (10) Å | µ = 0.07 mm−1 |
b = 8.0528 (8) Å | T = 296 K |
c = 32.571 (3) Å | 0.30 × 0.25 × 0.20 mm |
Bruker Kappa APEXII CCD diffractometer | 2692 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2004) | 1737 reflections with I > 2σ(I) |
Tmin = 0.980, Tmax = 0.987 | Rint = 0.041 |
17121 measured reflections |
R[F2 > 2σ(F2)] = 0.061 | 0 restraints |
wR(F2) = 0.187 | H-atom parameters constrained |
S = 1.08 | Δρmax = 0.21 e Å−3 |
2692 reflections | Δρmin = −0.16 e Å−3 |
167 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
C6 | 0.0030 (3) | 0.4888 (3) | 0.18005 (8) | 0.0768 (8) | |
H6 | −0.0658 | 0.5293 | 0.1651 | 0.092* | |
C14 | 0.0373 (2) | 0.2889 (2) | 0.03147 (7) | 0.0523 (6) | |
H14 | −0.0182 | 0.3671 | 0.0425 | 0.063* | |
C13 | 0.0307 (2) | 0.2534 (3) | −0.00941 (7) | 0.0528 (6) | |
H13 | −0.0297 | 0.3073 | −0.0255 | 0.063* | |
C15 | 0.1898 (3) | −0.0172 (4) | −0.08750 (8) | 0.0805 (8) | |
H15A | 0.2757 | 0.0243 | −0.0875 | 0.121* | |
H15B | 0.1629 | −0.0378 | −0.1152 | 0.121* | |
H15C | 0.1862 | −0.1187 | −0.0721 | 0.121* | |
C16 | 0.0139 (3) | 0.1841 (4) | −0.09499 (8) | 0.0809 (8) | |
H16A | −0.0705 | 0.1568 | −0.0857 | 0.121* | |
H16B | 0.0247 | 0.1468 | −0.1228 | 0.121* | |
H16C | 0.0258 | 0.3022 | −0.0938 | 0.121* | |
C10 | 0.2053 (2) | 0.0940 (2) | 0.03889 (7) | 0.0530 (6) | |
H10 | 0.2640 | 0.0380 | 0.0552 | 0.064* | |
C1 | 0.1192 (4) | 0.5064 (5) | 0.29002 (9) | 0.1148 (13) | |
H1A | 0.1367 | 0.6223 | 0.2939 | 0.172* | |
H1B | 0.1863 | 0.4416 | 0.3021 | 0.172* | |
H1C | 0.0395 | 0.4787 | 0.3029 | 0.172* | |
C3 | 0.2043 (3) | 0.3782 (4) | 0.22509 (9) | 0.0862 (9) | |
H3 | 0.2737 | 0.3400 | 0.2402 | 0.103* | |
C7 | 0.0115 (3) | 0.5248 (4) | 0.22110 (9) | 0.0831 (9) | |
H7 | −0.0521 | 0.5886 | 0.2333 | 0.100* | |
C4 | 0.1978 (3) | 0.3420 (4) | 0.18370 (8) | 0.0788 (8) | |
H4 | 0.2632 | 0.2823 | 0.1713 | 0.095* | |
C2 | 0.1112 (3) | 0.4694 (3) | 0.24474 (8) | 0.0791 (8) | |
C9 | 0.1257 (2) | 0.2105 (2) | 0.05712 (7) | 0.0482 (5) | |
C12 | 0.11276 (19) | 0.1375 (2) | −0.02776 (7) | 0.0477 (5) | |
C5 | 0.0941 (2) | 0.3941 (3) | 0.16042 (7) | 0.0607 (6) | |
N2 | 0.10664 (19) | 0.1037 (2) | −0.06899 (6) | 0.0632 (6) | |
N1 | 0.0775 (2) | 0.3645 (2) | 0.11798 (6) | 0.0630 (6) | |
C11 | 0.2007 (2) | 0.0582 (2) | −0.00217 (7) | 0.0527 (6) | |
H11 | 0.2567 | −0.0197 | −0.0131 | 0.063* | |
C8 | 0.1356 (2) | 0.2458 (3) | 0.10037 (7) | 0.0541 (6) | |
H22E | 0.1874 | 0.1778 | 0.1163 | 0.065* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C6 | 0.0832 (19) | 0.0809 (18) | 0.0664 (17) | 0.0181 (15) | 0.0077 (14) | 0.0081 (14) |
C14 | 0.0464 (12) | 0.0402 (11) | 0.0703 (15) | 0.0053 (9) | 0.0058 (11) | 0.0021 (10) |
C13 | 0.0470 (13) | 0.0445 (11) | 0.0669 (14) | 0.0029 (9) | −0.0055 (11) | 0.0087 (10) |
C15 | 0.0811 (19) | 0.0882 (19) | 0.0721 (16) | 0.0062 (15) | 0.0070 (15) | −0.0134 (14) |
C16 | 0.099 (2) | 0.0781 (18) | 0.0657 (16) | 0.0016 (15) | −0.0108 (15) | 0.0086 (13) |
C10 | 0.0463 (13) | 0.0431 (11) | 0.0696 (14) | 0.0046 (9) | −0.0046 (11) | 0.0095 (10) |
C1 | 0.147 (3) | 0.132 (3) | 0.0655 (18) | −0.002 (3) | 0.001 (2) | −0.0060 (18) |
C3 | 0.094 (2) | 0.091 (2) | 0.0741 (18) | 0.0121 (17) | −0.0165 (16) | −0.0009 (15) |
C7 | 0.092 (2) | 0.085 (2) | 0.0722 (18) | 0.0140 (16) | 0.0183 (17) | 0.0006 (15) |
C4 | 0.077 (2) | 0.0833 (19) | 0.0759 (17) | 0.0150 (15) | −0.0038 (15) | −0.0099 (14) |
C2 | 0.103 (2) | 0.0753 (18) | 0.0593 (16) | −0.0054 (16) | 0.0072 (16) | 0.0052 (13) |
C9 | 0.0459 (12) | 0.0381 (11) | 0.0607 (13) | −0.0047 (8) | 0.0043 (10) | 0.0078 (9) |
C12 | 0.0422 (12) | 0.0411 (11) | 0.0597 (13) | −0.0066 (8) | 0.0038 (10) | 0.0035 (9) |
C5 | 0.0697 (17) | 0.0530 (13) | 0.0592 (14) | 0.0018 (11) | 0.0053 (12) | 0.0076 (11) |
N2 | 0.0613 (13) | 0.0650 (12) | 0.0632 (12) | 0.0064 (10) | −0.0013 (10) | 0.0009 (10) |
N1 | 0.0684 (14) | 0.0608 (12) | 0.0599 (12) | 0.0050 (10) | 0.0046 (10) | 0.0042 (9) |
C11 | 0.0443 (13) | 0.0429 (11) | 0.0710 (14) | 0.0051 (9) | 0.0024 (11) | 0.0004 (10) |
C8 | 0.0524 (13) | 0.0428 (12) | 0.0670 (14) | −0.0018 (9) | 0.0016 (11) | 0.0110 (10) |
C6—C7 | 1.371 (4) | C1—C2 | 1.507 (4) |
C6—C5 | 1.378 (3) | C1—H1A | 0.9600 |
C6—H6 | 0.9300 | C1—H1B | 0.9600 |
C14—C13 | 1.364 (3) | C1—H1C | 0.9600 |
C14—C9 | 1.398 (3) | C3—C2 | 1.379 (4) |
C14—H14 | 0.9300 | C3—C4 | 1.381 (4) |
C13—C12 | 1.403 (3) | C3—H3 | 0.9300 |
C13—H13 | 0.9300 | C7—C2 | 1.373 (4) |
C15—N2 | 1.439 (3) | C7—H7 | 0.9300 |
C15—H15A | 0.9600 | C4—C5 | 1.390 (3) |
C15—H15B | 0.9600 | C4—H4 | 0.9300 |
C15—H15C | 0.9600 | C9—C8 | 1.441 (3) |
C16—N2 | 1.443 (3) | C12—N2 | 1.372 (3) |
C16—H16A | 0.9600 | C12—C11 | 1.397 (3) |
C16—H16B | 0.9600 | C5—N1 | 1.413 (3) |
C16—H16C | 0.9600 | N1—C8 | 1.270 (3) |
C10—C11 | 1.369 (3) | C11—H11 | 0.9300 |
C10—C9 | 1.389 (3) | C8—H22E | 0.9300 |
C10—H10 | 0.9300 | ||
C7—C6—C5 | 121.6 (3) | C2—C3—H3 | 119.0 |
C7—C6—H6 | 119.2 | C4—C3—H3 | 119.0 |
C5—C6—H6 | 119.2 | C6—C7—C2 | 121.8 (3) |
C13—C14—C9 | 121.5 (2) | C6—C7—H7 | 119.1 |
C13—C14—H14 | 119.3 | C2—C7—H7 | 119.1 |
C9—C14—H14 | 119.3 | C3—C4—C5 | 120.5 (3) |
C14—C13—C12 | 121.6 (2) | C3—C4—H4 | 119.8 |
C14—C13—H13 | 119.2 | C5—C4—H4 | 119.8 |
C12—C13—H13 | 119.2 | C7—C2—C3 | 116.8 (3) |
N2—C15—H15A | 109.5 | C7—C2—C1 | 121.8 (3) |
N2—C15—H15B | 109.5 | C3—C2—C1 | 121.4 (3) |
H15A—C15—H15B | 109.5 | C10—C9—C14 | 116.6 (2) |
N2—C15—H15C | 109.5 | C10—C9—C8 | 120.6 (2) |
H15A—C15—H15C | 109.5 | C14—C9—C8 | 122.8 (2) |
H15B—C15—H15C | 109.5 | N2—C12—C11 | 121.6 (2) |
N2—C16—H16A | 109.5 | N2—C12—C13 | 121.4 (2) |
N2—C16—H16B | 109.5 | C11—C12—C13 | 117.1 (2) |
H16A—C16—H16B | 109.5 | C6—C5—C4 | 117.1 (2) |
N2—C16—H16C | 109.5 | C6—C5—N1 | 117.5 (2) |
H16A—C16—H16C | 109.5 | C4—C5—N1 | 125.3 (2) |
H16B—C16—H16C | 109.5 | C12—N2—C15 | 121.1 (2) |
C11—C10—C9 | 122.6 (2) | C12—N2—C16 | 121.1 (2) |
C11—C10—H10 | 118.7 | C15—N2—C16 | 117.7 (2) |
C9—C10—H10 | 118.7 | C8—N1—C5 | 120.6 (2) |
C2—C1—H1A | 109.5 | C10—C11—C12 | 120.6 (2) |
C2—C1—H1B | 109.5 | C10—C11—H11 | 119.7 |
H1A—C1—H1B | 109.5 | C12—C11—H11 | 119.7 |
C2—C1—H1C | 109.5 | N1—C8—C9 | 123.8 (2) |
H1A—C1—H1C | 109.5 | N1—C8—H22E | 118.1 |
H1B—C1—H1C | 109.5 | C9—C8—H22E | 118.1 |
C2—C3—C4 | 122.0 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
C11—H11···Cg1i | 0.93 | 2.94 | 3.670 (2) | 137 |
Symmetry code: (i) x, −y+3/2, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C16H18N2 |
Mr | 238.32 |
Crystal system, space group | Orthorhombic, Pbca |
Temperature (K) | 296 |
a, b, c (Å) | 10.4814 (10), 8.0528 (8), 32.571 (3) |
V (Å3) | 2749.1 (4) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.07 |
Crystal size (mm) | 0.30 × 0.25 × 0.20 |
Data collection | |
Diffractometer | Bruker Kappa APEXII CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2004) |
Tmin, Tmax | 0.980, 0.987 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 17121, 2692, 1737 |
Rint | 0.041 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.061, 0.187, 1.08 |
No. of reflections | 2692 |
No. of parameters | 167 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.21, −0.16 |
Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT (Bruker, 2004), SAINT and XPREP (Bruker, 2004), SIR92 (Altomare et al., 1993), ORTEP-3 for Windows (Farrugia, 2012), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
C11—H11···Cg1i | 0.93 | 2.94 | 3.670 (2) | 137 |
Symmetry code: (i) x, −y+3/2, z−1/2. |
Acknowledgements
The author acknowledges the STIC, Cochin 682 022, for the single-crystal XRD facility. The authors also thank Mr P. Narayanan and Dr K·Sethusankar, RKM Vivekananda College (Autonomous), Chennai 600 004, and VIT University for providing the excellent research facilities.
References
Altomare, A., Cascarano, G., Giacovazzo, C. & Guagliardi, A. (1993). J. Appl. Cryst. 26, 343–350. CrossRef Web of Science IUCr Journals Google Scholar
Bruker (2004). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854. Web of Science CrossRef CAS IUCr Journals Google Scholar
Fun, H.-K., Quah, C. K., Huang, C. & Yu, H. (2011). Acta Cryst. E67, o1273–o1274. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Khalaji, A. D. & Simpson, J. (2009). Acta Cryst. E65, o553. Web of Science CSD CrossRef IUCr Journals Google Scholar
Shah, S., Vyas, R. & Mehta, R. H. (1992). J. Indian Chem. Soc. 69, 590–590. CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
Ünver, H., Karakas, A. & Elmali, A. (2004). J. Mol. Struct. 702, 49–54. Google Scholar
Xia, D.-G., Ye, Y.-F. & Lei, K.-W. (2009). Acta Cryst. E65, o3168. Web of Science CSD CrossRef IUCr Journals Google Scholar
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Schiff bases are among the most useful ligands in coordination chemistry as they readily form stable complexes with most transition metals (Xia et al., 2009). They are known to exibit potent anti-bacterial, anti-convulsant, anti-inflammatory and anti-cancer activities (Shah et al., 1992). In addition to that, they show Non-linear optical properties (Ünver et al., 2004). Therefore, successful application of Schiff bases requires a careful study of their characteristics.
The title compound, C16H18N2, exists in a trans configuration with respect to the C═N bond[1.270 (3) Å]. The N1═C8 bond length of 1.270 (3) Å is shorter than the N–C bond [1.413 (3) Å], indicating a typical imine double bond. The C–N–C angle is 120.6 (2) °. X-ray analysis confirms the molecular structure and atom connectivity as illustrated in Fig. 1.
The least square plane of the dimethylamine group has a dihedral angle of 1.31 (2) ° with the phenyl ring (C9–C14), which shows that they are almost coplanar to each other. The dimethylamine group attached phenyl ring (C9–C14) forms a dihedral angle of 11.70 (2) Å with the methyl group attached phenyl ring (C2–C7).
The crystal packing is stabilized by C11—H11···Cg1i inter-molecular interactions, where Cg1 is the center of gravity of (C8–C14) phenyl ring. The symmetry code is 1/2-X,-1/2+Y,Z.