(2E)-2-[4-(Di­methyl­amino)­benzyl­idene]-5-methyl­cyclo­hexa­none

Jebapriya, J.C.; Reuben Jonathan, D.; Prasana, J.C.; Usha, G.

doi:10.1107/S2414314617017060

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 2| Part 12| December 2017| x171706

https://doi.org/10.1107/S2414314617017060

Open

access

(2E)-2-[4-(Dimethylamino)benzylidene]-5-methylcyclohexanone

J. Christina Jebapriya,^a D. Reuben Jonathan,^b Johanan Christian Prasana ^a and G. Usha ^c ^*

^aDepartment of Physics, Madras Christian College, Chennai-59, Tamilnadu, India, ^bDepartment of Chemistry, Madras Christian College, Chennai-59, Tamilnadu, India, and ^cPG and Research Department of Physics, Queen Mary's College, Chennai-4, Tamilnadu, India
^*Correspondence e-mail: guqmc@yahoo.com

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 15 November 2017; accepted 27 November 2017; online 5 December 2017)

In the title compound, C₁₆H₂₁NO, the cyclohexanone ring adopts a half-chair conformation; the dihedral angle between this ring (all atoms) and the benzene ring is 41.74 (16)°. No directional interactions could be identified in the crystal.

Keywords: crystal structure; cyclohexanone; molecular interactions and conformation.

CCDC reference: 1499112

Structure description

Cyclohexanone derivatives have various applications as drugs (e.g. Chen et al., 2010 ). As part our studies in this area, we now describe the synthesis via a Claissen–Schmidt condensation and crystal structure of the title compound (Fig. 1). In the arbitrarily chosen asymmetric molecule, C13 has an R configuration, but symmetry generates a racemic mixture in the crystal.

Figure 1
The molecular structure, with displacement ellipsoids drawn at the 30% probability level.

The geometric parameters for the title compound are comparable with the corresponding values for similar reported structures (e.g. Shalini et al., 2013 ). The cyclohexanone ring adopts a half-chair conformation, with C10/C11/C14/C15 roughly coplanar (r.m.s. deviation = 0.075 Å) and C12 and C13 deviating by 0.465 (5) and −0.234 (4) Å, respectively, from the other atoms. The dihedral angle between the cyclohexanone ring (all atoms) and the benzene ring is 41.74 (15)°. The N1/C1/C2 dimethylamino group is almost coplanar with its attached benzene ring [dihedral angle = 2.6 (4)°] and the bond-angle sum at the nitrogen atom of 359.8° clearly indicates sp² hybridization.

No directional interactions could be identified in the crystal (Fig. 2) and van der Waals forces must be responsible for crystal cohesion.

Figure 2
The packing viewed down [010].

Synthesis and crystallization

An aqueous solution of NaOH (10%, 10 ml) was added to a solution of 3-methylcyclohexanone (0.02 mol) and 4-N,N-methylaminobenzaldehyde (0.02 mol) in absolute ethanol (40 ml). The reaction mixture was stirred for 2 h and was left overnight. On addition of ice-cold water, a dark-yellow solid was obtained, which was filtered, washed with ice-cold water and dried. The product was recrystallized from ethyl acetate solution to yield yellow blocks after seven days (yield: 87%, m.p. 70°C).

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1.

Table 1
Experimental details

Crystal data
Chemical formula	C₁₆H₂₁NO
M_r	243.34
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	296
a, b, c (Å)	20.3655 (16), 7.6148 (7), 18.2999 (16)
β (°)	99.254 (3)
V (Å³)	2801.0 (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
Absorption correction	Multi-scan (SADABS; Bruker, 2004 )
T_min, T_max	0.979, 0.986
No. of measured, independent and observed [I > 2σ(I)] reflections	19385, 2462, 1528
R_int	0.030
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.073, 0.218, 1.07
No. of reflections	2458
No. of parameters	167
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.25, −0.19
Computer programs: APEX2 (Bruker, 2004), APEX2 and SAINT (Bruker, 2004), SAINT and XPREP (Bruker, 2004), SIR92 (Altomare et al., 1993 ), SHELXL2014 (Sheldrick, 2015 ), ORTEP-3 for Windows (Farrugia, 2012 ).

Structural data

CCDC reference: 1499112

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S2414314617017060/hb4183sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617017060/hb4183Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314617017060/hb4183Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: 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: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2015).

(2E)-2-[4-(Dimethylamino)benzylidene]-5-methylcyclohexanone top

Crystal data top

C₁₆H₂₁NO	F(000) = 1056
M_r = 243.34	D_x = 1.154 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 20.3655 (16) Å	Cell parameters from 6070 reflections
b = 7.6148 (7) Å	θ = 2.8–25.5°
c = 18.2999 (16) Å	µ = 0.07 mm⁻¹
β = 99.254 (3)°	T = 296 K
V = 2801.0 (4) Å³	Block, yellow
Z = 8	0.30 × 0.25 × 0.20 mm

Data collection top

Bruker Kappa APEXII CCD diffractometer	2462 independent reflections
Radiation source: fine-focus sealed tube	1528 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.030
ω and φ scan	θ_max = 25.0°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Bruker, 2004)	h = −24→22
T_min = 0.979, T_max = 0.986	k = −9→9
19385 measured reflections	l = −21→21

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.073	w = 1/[σ²(F_o²) + (0.0719P)² + 5.4525P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.218	(Δ/σ)_max < 0.001
S = 1.07	Δρ_max = 0.25 e Å⁻³
2458 reflections	Δρ_min = −0.19 e Å⁻³
167 parameters	Extinction correction: SHELXL2014 (Sheldrick, 2015), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0022 (6)

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. Hydrogen atoms were positioned geometrically and treated as riding on their parent atoms and refined with C—H distances of 0.93–0.97 Å, with U_iso(H)= 1.2U_eq(C) or U_iso(H) = 1.5U_eq(methyl C).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
C1	0.40379 (18)	0.7797 (6)	0.2188 (2)	0.0897 (12)
H1A	0.4390	0.7688	0.2603	0.135*
H1B	0.3919	0.9012	0.2115	0.135*
H1C	0.4185	0.7348	0.1752	0.135*
C2	0.3551 (2)	0.5670 (6)	0.2965 (2)	0.0978 (13)
H2A	0.3988	0.5828	0.3246	0.147*
H2B	0.3498	0.4472	0.2803	0.147*
H2C	0.3223	0.5946	0.3269	0.147*
C3	0.28784 (15)	0.6857 (4)	0.18527 (16)	0.0596 (8)
C4	0.23324 (16)	0.5821 (4)	0.19661 (18)	0.0659 (9)
H4	0.2375	0.5059	0.2368	0.079*
C5	0.17401 (16)	0.5914 (4)	0.14940 (17)	0.0658 (9)
H5	0.1392	0.5197	0.1582	0.079*
C6	0.16364 (15)	0.7044 (4)	0.08843 (16)	0.0578 (8)
C7	0.21890 (16)	0.8012 (4)	0.07624 (17)	0.0619 (8)
H7	0.2150	0.8736	0.0349	0.074*
C8	0.27912 (16)	0.7939 (4)	0.12295 (17)	0.0637 (9)
H8	0.3144	0.8622	0.1128	0.076*
C9	0.10106 (16)	0.7265 (4)	0.03870 (17)	0.0614 (8)
H9	0.1051	0.7536	−0.0099	0.074*
C10	0.03833 (16)	0.7142 (4)	0.05177 (16)	0.0593 (8)
C11	0.01972 (17)	0.6781 (5)	0.12709 (17)	0.0714 (10)
H11A	0.0166	0.5522	0.1338	0.086*
H11B	0.0547	0.7220	0.1650	0.086*
C12	−0.04529 (19)	0.7616 (6)	0.1373 (2)	0.0830 (11)
H12A	−0.0566	0.7253	0.1845	0.100*
H12B	−0.0403	0.8883	0.1382	0.100*
C13	−0.10030 (18)	0.7122 (5)	0.0772 (2)	0.0778 (10)
H13	−0.1018	0.5836	0.0755	0.093*
C14	−0.08539 (17)	0.7743 (5)	0.00311 (19)	0.0738 (10)
H14A	−0.1154	0.7144	−0.0355	0.089*
H14B	−0.0954	0.8988	−0.0014	0.089*
C15	−0.01578 (17)	0.7473 (4)	−0.01116 (18)	0.0676 (9)
C16	−0.1685 (2)	0.7745 (6)	0.0903 (3)	0.1008 (14)
H16A	−0.2018	0.7330	0.0509	0.151*
H16B	−0.1693	0.9005	0.0914	0.151*
H16C	−0.1774	0.7292	0.1366	0.151*
N1	0.34694 (14)	0.6815 (4)	0.23302 (15)	0.0731 (8)
O1	−0.00436 (13)	0.7606 (4)	−0.07460 (13)	0.0917 (9)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.068 (2)	0.119 (3)	0.084 (3)	−0.014 (2)	0.0187 (19)	0.003 (2)
C2	0.091 (3)	0.114 (3)	0.080 (3)	−0.011 (2)	−0.011 (2)	0.023 (2)
C3	0.0627 (19)	0.068 (2)	0.0508 (17)	0.0034 (15)	0.0157 (15)	−0.0007 (15)
C4	0.071 (2)	0.068 (2)	0.0604 (19)	−0.0013 (17)	0.0127 (16)	0.0149 (16)
C5	0.069 (2)	0.063 (2)	0.066 (2)	−0.0061 (16)	0.0114 (16)	0.0093 (16)
C6	0.0641 (19)	0.0634 (19)	0.0476 (16)	0.0003 (15)	0.0144 (14)	−0.0014 (14)
C7	0.070 (2)	0.068 (2)	0.0523 (17)	0.0066 (16)	0.0229 (15)	0.0073 (15)
C8	0.066 (2)	0.070 (2)	0.0610 (19)	−0.0038 (16)	0.0251 (16)	0.0043 (16)
C9	0.074 (2)	0.063 (2)	0.0482 (17)	0.0002 (16)	0.0143 (15)	0.0002 (14)
C10	0.071 (2)	0.0618 (19)	0.0446 (16)	−0.0026 (15)	0.0094 (14)	−0.0016 (14)
C11	0.074 (2)	0.092 (3)	0.0482 (17)	−0.0057 (19)	0.0105 (15)	0.0011 (17)
C12	0.084 (3)	0.106 (3)	0.062 (2)	0.003 (2)	0.0206 (19)	−0.004 (2)
C13	0.074 (2)	0.088 (3)	0.074 (2)	0.0013 (19)	0.0185 (18)	−0.003 (2)
C14	0.074 (2)	0.077 (2)	0.069 (2)	0.0023 (18)	0.0063 (17)	0.0050 (18)
C15	0.079 (2)	0.070 (2)	0.0534 (19)	−0.0015 (17)	0.0084 (16)	0.0005 (16)
C16	0.082 (3)	0.114 (4)	0.109 (3)	0.013 (2)	0.022 (2)	0.003 (3)
N1	0.0655 (17)	0.089 (2)	0.0648 (17)	−0.0025 (15)	0.0109 (14)	0.0141 (15)
O1	0.0925 (19)	0.129 (2)	0.0523 (14)	0.0035 (16)	0.0089 (12)	0.0090 (14)

Geometric parameters (Å, º) top

C1—N1	1.437 (4)	C9—C10	1.340 (4)
C1—H1A	0.9600	C9—H9	0.9300
C1—H1B	0.9600	C10—C15	1.482 (5)
C1—H1C	0.9600	C10—C11	1.512 (4)
C2—N1	1.440 (4)	C11—C12	1.507 (5)
C2—H2A	0.9600	C11—H11A	0.9700
C2—H2B	0.9600	C11—H11B	0.9700
C2—H2C	0.9600	C12—C13	1.486 (5)
C3—N1	1.369 (4)	C12—H12A	0.9700
C3—C8	1.395 (4)	C12—H12B	0.9700
C3—C4	1.406 (4)	C13—C14	1.513 (5)
C4—C5	1.368 (4)	C13—C16	1.522 (5)
C4—H4	0.9300	C13—H13	0.9800
C5—C6	1.398 (4)	C14—C15	1.497 (5)
C5—H5	0.9300	C14—H14A	0.9700
C6—C7	1.393 (4)	C14—H14B	0.9700
C6—C9	1.452 (4)	C15—O1	1.224 (4)
C7—C8	1.379 (4)	C16—H16A	0.9600
C7—H7	0.9300	C16—H16B	0.9600
C8—H8	0.9300	C16—H16C	0.9600

N1—C1—H1A	109.5	C12—C11—C10	113.0 (3)
N1—C1—H1B	109.5	C12—C11—H11A	109.0
H1A—C1—H1B	109.5	C10—C11—H11A	109.0
N1—C1—H1C	109.5	C12—C11—H11B	109.0
H1A—C1—H1C	109.5	C10—C11—H11B	109.0
H1B—C1—H1C	109.5	H11A—C11—H11B	107.8
N1—C2—H2A	109.5	C13—C12—C11	112.0 (3)
N1—C2—H2B	109.5	C13—C12—H12A	109.2
H2A—C2—H2B	109.5	C11—C12—H12A	109.2
N1—C2—H2C	109.5	C13—C12—H12B	109.2
H2A—C2—H2C	109.5	C11—C12—H12B	109.2
H2B—C2—H2C	109.5	H12A—C12—H12B	107.9
N1—C3—C8	121.2 (3)	C12—C13—C14	110.4 (3)
N1—C3—C4	121.8 (3)	C12—C13—C16	113.8 (3)
C8—C3—C4	116.9 (3)	C14—C13—C16	111.3 (3)
C5—C4—C3	121.0 (3)	C12—C13—H13	107.0
C5—C4—H4	119.5	C14—C13—H13	107.0
C3—C4—H4	119.5	C16—C13—H13	107.0
C4—C5—C6	122.7 (3)	C15—C14—C13	116.5 (3)
C4—C5—H5	118.6	C15—C14—H14A	108.2
C6—C5—H5	118.6	C13—C14—H14A	108.2
C7—C6—C5	115.5 (3)	C15—C14—H14B	108.2
C7—C6—C9	119.2 (3)	C13—C14—H14B	108.2
C5—C6—C9	125.2 (3)	H14A—C14—H14B	107.3
C8—C7—C6	122.7 (3)	O1—C15—C10	121.3 (3)
C8—C7—H7	118.6	O1—C15—C14	118.9 (3)
C6—C7—H7	118.6	C10—C15—C14	119.7 (3)
C7—C8—C3	120.9 (3)	C13—C16—H16A	109.5
C7—C8—H8	119.5	C13—C16—H16B	109.5
C3—C8—H8	119.5	H16A—C16—H16B	109.5
C10—C9—C6	130.2 (3)	C13—C16—H16C	109.5
C10—C9—H9	114.9	H16A—C16—H16C	109.5
C6—C9—H9	114.9	H16B—C16—H16C	109.5
C9—C10—C15	117.4 (3)	C3—N1—C1	121.6 (3)
C9—C10—C11	124.1 (3)	C3—N1—C2	120.3 (3)
C15—C10—C11	118.4 (3)	C1—N1—C2	117.9 (3)

N1—C3—C4—C5	178.2 (3)	C10—C11—C12—C13	53.8 (4)
C8—C3—C4—C5	−1.6 (5)	C11—C12—C13—C14	−61.4 (4)
C3—C4—C5—C6	−0.9 (5)	C11—C12—C13—C16	172.7 (3)
C4—C5—C6—C7	3.3 (5)	C12—C13—C14—C15	43.0 (5)
C4—C5—C6—C9	−176.7 (3)	C16—C13—C14—C15	170.3 (3)
C5—C6—C7—C8	−3.2 (5)	C9—C10—C15—O1	10.1 (5)
C9—C6—C7—C8	176.8 (3)	C11—C10—C15—O1	−172.9 (3)
C6—C7—C8—C3	0.8 (5)	C9—C10—C15—C14	−166.7 (3)
N1—C3—C8—C7	−178.2 (3)	C11—C10—C15—C14	10.3 (5)
C4—C3—C8—C7	1.7 (5)	C13—C14—C15—O1	165.0 (3)
C7—C6—C9—C10	−148.5 (3)	C13—C14—C15—C10	−18.1 (5)
C5—C6—C9—C10	31.5 (5)	C8—C3—N1—C1	−3.9 (5)
C6—C9—C10—C15	179.0 (3)	C4—C3—N1—C1	176.2 (3)
C6—C9—C10—C11	2.3 (6)	C8—C3—N1—C2	−179.2 (3)
C9—C10—C11—C12	149.3 (3)	C4—C3—N1—C2	1.0 (5)
C15—C10—C11—C12	−27.4 (5)

Acknowledgements

The authors thank the Central Instrumentation Facility, Queen Mary's College, Chennai-4, for the computing facility and the SAIF, IIT, Madras, for the X-ray data collection facility.

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, XPREP and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Chen, L., Zhang, L., Wang, Z., Wu, Y. & Liang, G. (2010). Acta Cryst. E66, o3309. Web of Science CSD CrossRef IUCr Journals Google Scholar
Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849–854. Web of Science CrossRef CAS IUCr Journals Google Scholar
Shalini, S., Girija, C. R., Karunakar, P., Jotani, M. M., Venugopala, K. N. & Venkatesha, T. V. (2013). Indian J. Chem. Sect. B, 52, 282–288. Google Scholar
Sheldrick, G. M. (2015). Acta Cryst. C71, 3–8. Web of Science CrossRef IUCr Journals Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.