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

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ISSN: 2056-9890

2-Iodo-3-(4-meth­­oxy­anilino)-5,5-di­methyl­cyclo­hex-2-en-1-one

aPost Graduate and Research Department of Physics, Agurchand Manmull Jain College, Chennai 600 114, India, and bOrganic Chemistry Division, Central Leather Research Institute, Chennai 600 020, India
*Correspondence e-mail: seshadri_pr@yahoo.com

(Received 12 January 2012; accepted 18 January 2012; online 25 January 2012)

The cyclo­hexene ring in the title compound, C15H18INO2, adopts a sofa conformation. The dihedral angle between the cyclo­hexene (through all ring atoms) and benzene rings is 63.3 (1)°. The mol­ecular conformation features an N—H⋯I short contact and the crystal packing features C—H⋯O hydrogen bonds.

Related literature

For the biological activity of cyclo­hex-2-enone derivatives, see: Correia et al. (2001[Correia, S. D., David, J. M., David, J. P., Chai, H. B., Pezzuto, J. M. & Cordell, G. A. (2001). Phytochemistry, 56, 781-784.]); Rebacz et al. (2007[Rebacz, B., Larsen, T. O., Clausen, M. H., Ronnest, M. H., Löffler, H., Ho, A. D. & Krämer, A. (2007). Cancer Res. 67, 6342-6350.]); Stadler et al. (1994[Stadler, M., Anke, H. & Sterner, O. J. (1994). J. Antibiot. 47, 1284-1289.]). For the use of cyclo­hex-2-enone in organic synthesis, see: Cokcer et al. (1995[Cokcer, W., Grayson, D. H. & Shannon, P. V. R. (1995). J. Chem. Soc. Perkin Trans. 1, pp. 1153-1162.]); Pandey et al. (2004[Pandey, S. C., Singh, S. S., Patro, B. & Ghosh, A. C. (2004). Indian J. Chem. Sect. B, 43, 2705-2707.]). For pukering parameters, see: Cremer & Pople, (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]). For related structures, see: Mohan et al. (2008[Mohan, R. T. S., Kamatchi, S., Subramanyam, M., Thiruvalluvar, A. & Linden, A. (2008). Acta Cryst. E64, o1066.]); North et al. (2011[North, H., Wutoh, K., Odoom, M. K., Karla, P., Scott, K. R. & Butcher, R. J. (2011). Acta Cryst. E67, o603-o604.]).

[Scheme 1]

Experimental

Crystal data
  • C15H18INO2

  • Mr = 371.20

  • Orthorhombic, P b c a

  • a = 15.922 (5) Å

  • b = 10.107 (5) Å

  • c = 19.034 (5) Å

  • V = 3063 (2) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 2.09 mm−1

  • T = 298 K

  • 0.20 × 0.20 × 0.20 mm

Data collection
  • Bruker SMART APEXII area-detector diffractometer

  • 15382 measured reflections

  • 3785 independent reflections

  • 2793 reflections with I > 2σ(I)

  • Rint = 0.025

Refinement
  • R[F2 > 2σ(F2)] = 0.027

  • wR(F2) = 0.074

  • S = 0.93

  • 3785 reflections

  • 172 parameters

  • H-atom parameters constrained

  • Δρmax = 0.46 e Å−3

  • Δρmin = −0.53 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C14—H14⋯O1i 0.93 2.39 3.313 (3) 174
N1—H1⋯I1 0.86 2.71 3.227 (2) 120
Symmetry code: (i) -x+1, -y, -z+1.

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2 and 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: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97, PLATON and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

Cyclohex-2-enone derivative exhibits antibacterial (Stadler et al., 1994) and anticancer (Correia et al., 2001; Rebacz et al., 2007) activities. Cyclohex-2-enone plays an important role in organic synthesis (Cokcer et al., 1995; Pandey et al., 2004). Against this background, the title compound was chosen for X-ray structure analysis (Fig. 1). The cyclohexene ring adopts a sofa conformation with the pukering parameters (Cremer & Pople, 1975) being q2=0.409 (3) Å, q3=-0.247 (3)Å and QT=0.478 (3) Å. The molecular structure is stabilised by N—H···I intramolecular interactions and the crystal packing is stabilised by C—H···O hydrogen bonds (Fig. 2 and Table 1).

Related literature top

For the biological activity of cyclohex-2-enone derivatives, see: Correia et al. (2001); Rebacz et al. (2007); Stadler et al. (1994). For the use of cyclohex-2-enone in organic synthesis, see: Cokcer et al. (1995); Pandey et al. (2004). For pukering parameters, see: Cremer & Pople, (1975). For related structures, see: Mohan et al. (2008); North et al. (2011).

Experimental top

1,3-cyclohexanedione (2 mmol), FeCl3.6H2O (5 mol), and 50 mg of sodium sulfate were succesively added in a dry Schlenk tube under argon. The solids were then dissolved in 3 mL of dichloromethane and stirred for 5 m. Aniline (2 mmol) was slowly added and the dark brown cloloured mixture was allowed to stir overnight. After completion, solvents were removed under vacuum and the crude oil was filtered on a plug of neutral alumina (eluent: dichloromethane/ methanol, 90/10). Solvents were then removed and enaminone product was obtained as a bright yellow solid. Then iodine (3 mmol) dissolved in CCl4/pyridine (1;1, 10 mL) was added dropwise under an atmosphere of argon to a solution of enaminone (1.5 mmol) in CCl4/pyridine (1;1, 10 mL) at 273 K. The mixture was stirred for 2 h during that time the temperature was allowed to raise to room temperature. The mixture was diluted with ethyl acetate (50 mL) and washed successively with 1 NHCl (4× 10 mL), sat. NaHCo3 (20 mL), 20% aqueous Na2S2O3 (20 mL) and dried (Na2SO4). Filtered and concentrated under reduced pressure, the residue was further purified by column chromatography to afford pure 2-iodo-5,5-dimethyl-3-(Phenylamino) cyclohex-2-enone.

Refinement top

Hydrogen atoms were positioned geometrically and allowed to ride on their parent atoms, with C—H = 0.93 - 0.97 Å and Uiso(H) = 1.5Ueq(C) for methyl H atoms and 1.2 Ueq(C) for other H atoms.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound showing the atom-numbering scheme and displacement ellipsoids drawn at the 30% probability level.
[Figure 2] Fig. 2. The crystal packing of the title compound. Hydrogen bonds are shown by dashed lines.
2-Iodo-3-(4-methoxyanilino)-5,5-dimethylcyclohex-2-en-1-one top
Crystal data top
C15H18INO2F(000) = 1472
Mr = 371.20Dx = 1.610 Mg m3
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 3785 reflections
a = 15.922 (5) Åθ = 2.1–28.3°
b = 10.107 (5) ŵ = 2.09 mm1
c = 19.034 (5) ÅT = 298 K
V = 3063 (2) Å3Block, colourless
Z = 80.20 × 0.20 × 0.20 mm
Data collection top
Bruker SMART APEXII area-detector
diffractometer
2793 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.025
Graphite monochromatorθmax = 28.3°, θmin = 2.1°
ω and ϕ scansh = 2021
15382 measured reflectionsk = 1313
3785 independent reflectionsl = 1825
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)] = 0.027Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.074H-atom parameters constrained
S = 0.93 w = 1/[σ2(Fo2) + (0.0379P)2 + 1.6353P]
where P = (Fo2 + 2Fc2)/3
3785 reflections(Δ/σ)max = 0.001
172 parametersΔρmax = 0.46 e Å3
0 restraintsΔρmin = 0.53 e Å3
Crystal data top
C15H18INO2V = 3063 (2) Å3
Mr = 371.20Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 15.922 (5) ŵ = 2.09 mm1
b = 10.107 (5) ÅT = 298 K
c = 19.034 (5) Å0.20 × 0.20 × 0.20 mm
Data collection top
Bruker SMART APEXII area-detector
diffractometer
2793 reflections with I > 2σ(I)
15382 measured reflectionsRint = 0.025
3785 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0270 restraints
wR(F2) = 0.074H-atom parameters constrained
S = 0.93Δρmax = 0.46 e Å3
3785 reflectionsΔρmin = 0.53 e Å3
172 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
I10.423501 (11)0.337299 (16)0.478996 (11)0.05300 (8)
O10.52198 (11)0.14887 (18)0.37743 (10)0.0540 (5)
O20.07995 (12)0.1517 (2)0.71999 (11)0.0631 (6)
N10.30564 (14)0.1095 (2)0.54533 (12)0.0460 (5)
H10.30920.19350.55200.055*
C10.45213 (16)0.0582 (3)0.38180 (14)0.0477 (6)
H1A0.49380.11260.40520.057*
H1B0.46210.06500.33170.057*
C20.46504 (15)0.0831 (2)0.40367 (13)0.0401 (5)
C30.40963 (15)0.1356 (2)0.45650 (14)0.0390 (5)
C40.35334 (15)0.0597 (2)0.49300 (12)0.0378 (5)
C50.34440 (16)0.0847 (2)0.47456 (12)0.0417 (5)
H5A0.28730.11250.48440.050*
H5B0.38160.13600.50440.050*
C60.36464 (17)0.1148 (3)0.39783 (13)0.0456 (6)
C70.3655 (2)0.2658 (3)0.38817 (17)0.0698 (9)
H7A0.37800.28660.34010.105*
H7B0.31150.30120.40030.105*
H7C0.40760.30390.41810.105*
C80.29981 (18)0.0539 (3)0.34872 (15)0.0585 (7)
H8A0.31420.07420.30090.088*
H8B0.29900.04030.35500.088*
H8C0.24530.08950.35920.088*
C90.24994 (15)0.0393 (2)0.59096 (12)0.0381 (5)
C100.16832 (16)0.0851 (2)0.59962 (13)0.0424 (5)
H100.15020.15940.57510.051*
C110.11454 (15)0.0208 (3)0.64420 (13)0.0455 (6)
H110.06050.05360.65080.055*
C120.13951 (16)0.0923 (3)0.67950 (12)0.0437 (6)
C130.22144 (16)0.1371 (3)0.67234 (13)0.0437 (6)
H130.23930.21190.69650.052*
C140.27628 (15)0.0696 (2)0.62894 (13)0.0432 (5)
H140.33170.09780.62520.052*
C150.1004 (2)0.2714 (3)0.75369 (18)0.0698 (9)
H15A0.05280.30200.78010.105*
H15B0.14690.25730.78490.105*
H15C0.11540.33640.71910.105*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
I10.05114 (12)0.03804 (11)0.06982 (15)0.00787 (7)0.00678 (9)0.00135 (8)
O10.0359 (9)0.0657 (12)0.0603 (12)0.0075 (8)0.0092 (9)0.0037 (9)
O20.0516 (12)0.0801 (16)0.0577 (12)0.0013 (10)0.0190 (9)0.0170 (10)
N10.0504 (12)0.0374 (11)0.0503 (12)0.0041 (9)0.0158 (10)0.0014 (9)
C10.0425 (13)0.0544 (15)0.0463 (14)0.0056 (12)0.0054 (12)0.0065 (12)
C20.0310 (11)0.0487 (14)0.0406 (13)0.0014 (10)0.0019 (10)0.0016 (11)
C30.0388 (12)0.0349 (12)0.0432 (13)0.0038 (9)0.0004 (10)0.0004 (10)
C40.0368 (12)0.0384 (12)0.0381 (12)0.0022 (10)0.0006 (10)0.0005 (10)
C50.0459 (14)0.0373 (12)0.0419 (13)0.0069 (10)0.0024 (11)0.0000 (10)
C60.0489 (14)0.0450 (14)0.0428 (14)0.0053 (11)0.0023 (12)0.0077 (11)
C70.088 (2)0.0530 (18)0.0683 (19)0.0100 (17)0.0057 (18)0.0191 (15)
C80.0502 (15)0.075 (2)0.0503 (16)0.0110 (15)0.0060 (13)0.0034 (14)
C90.0406 (12)0.0369 (11)0.0370 (12)0.0015 (10)0.0040 (10)0.0040 (10)
C100.0464 (13)0.0411 (13)0.0398 (13)0.0056 (11)0.0006 (11)0.0000 (10)
C110.0354 (12)0.0572 (16)0.0440 (13)0.0067 (11)0.0054 (11)0.0043 (12)
C120.0440 (13)0.0552 (15)0.0318 (12)0.0019 (11)0.0072 (11)0.0021 (11)
C130.0458 (14)0.0488 (14)0.0367 (13)0.0052 (11)0.0041 (11)0.0042 (10)
C140.0358 (12)0.0499 (14)0.0440 (13)0.0078 (11)0.0038 (11)0.0008 (11)
C150.083 (2)0.067 (2)0.0587 (18)0.0143 (18)0.0167 (17)0.0092 (16)
Geometric parameters (Å, º) top
I1—C32.095 (3)C7—H7A0.9600
O1—C21.230 (3)C7—H7B0.9600
O2—C121.361 (3)C7—H7C0.9600
O2—C151.407 (4)C8—H8A0.9600
N1—C41.350 (3)C8—H8B0.9600
N1—C91.430 (3)C8—H8C0.9600
N1—H10.8600C9—C141.382 (3)
C1—C21.501 (4)C9—C101.389 (3)
C1—C61.537 (4)C10—C111.369 (3)
C1—H1A0.9700C10—H100.9300
C1—H1B0.9700C11—C121.385 (4)
C2—C31.439 (3)C11—H110.9300
C3—C41.369 (3)C12—C131.387 (3)
C4—C51.508 (3)C13—C141.382 (3)
C5—C61.526 (3)C13—H130.9300
C5—H5A0.9700C14—H140.9300
C5—H5B0.9700C15—H15A0.9600
C6—C81.523 (4)C15—H15B0.9600
C6—C71.537 (4)C15—H15C0.9600
C12—O2—C15118.4 (2)C6—C7—H7C109.5
C4—N1—C9127.7 (2)H7A—C7—H7C109.5
C4—N1—H1116.1H7B—C7—H7C109.5
C9—N1—H1116.1C6—C8—H8A109.5
C2—C1—C6115.0 (2)C6—C8—H8B109.5
C2—C1—H1A108.5H8A—C8—H8B109.5
C6—C1—H1A108.5C6—C8—H8C109.5
C2—C1—H1B108.5H8A—C8—H8C109.5
C6—C1—H1B108.5H8B—C8—H8C109.5
H1A—C1—H1B107.5C14—C9—C10119.1 (2)
O1—C2—C3122.4 (2)C14—C9—N1121.7 (2)
O1—C2—C1120.2 (2)C10—C9—N1119.1 (2)
C3—C2—C1117.4 (2)C11—C10—C9120.0 (2)
C4—C3—C2123.3 (2)C11—C10—H10120.0
C4—C3—I1120.70 (18)C9—C10—H10120.0
C2—C3—I1115.92 (17)C10—C11—C12120.9 (2)
N1—C4—C3122.3 (2)C10—C11—H11119.6
N1—C4—C5118.7 (2)C12—C11—H11119.6
C3—C4—C5119.1 (2)O2—C12—C11116.0 (2)
C4—C5—C6113.3 (2)O2—C12—C13124.5 (2)
C4—C5—H5A108.9C11—C12—C13119.4 (2)
C6—C5—H5A108.9C14—C13—C12119.5 (2)
C4—C5—H5B108.9C14—C13—H13120.3
C6—C5—H5B108.9C12—C13—H13120.3
H5A—C5—H5B107.7C9—C14—C13120.9 (2)
C8—C6—C5111.3 (2)C9—C14—H14119.5
C8—C6—C1110.0 (2)C13—C14—H14119.5
C5—C6—C1107.9 (2)O2—C15—H15A109.5
C8—C6—C7109.5 (2)O2—C15—H15B109.5
C5—C6—C7108.3 (2)H15A—C15—H15B109.5
C1—C6—C7109.7 (2)O2—C15—H15C109.5
C6—C7—H7A109.5H15A—C15—H15C109.5
C6—C7—H7B109.5H15B—C15—H15C109.5
H7A—C7—H7B109.5
C6—C1—C2—O1160.3 (2)C2—C1—C6—C871.8 (3)
C6—C1—C2—C320.7 (3)C2—C1—C6—C549.8 (3)
O1—C2—C3—C4171.1 (2)C2—C1—C6—C7167.7 (2)
C1—C2—C3—C47.9 (4)C4—N1—C9—C1453.2 (4)
O1—C2—C3—I16.0 (3)C4—N1—C9—C10129.6 (3)
C1—C2—C3—I1174.98 (17)C14—C9—C10—C111.4 (4)
C9—N1—C4—C3174.5 (2)N1—C9—C10—C11178.7 (2)
C9—N1—C4—C55.2 (4)C9—C10—C11—C122.0 (4)
C2—C3—C4—N1175.8 (2)C15—O2—C12—C11176.3 (3)
I1—C3—C4—N11.1 (3)C15—O2—C12—C134.2 (4)
C2—C3—C4—C53.9 (4)C10—C11—C12—O2177.1 (2)
I1—C3—C4—C5179.19 (17)C10—C11—C12—C133.3 (4)
N1—C4—C5—C6151.7 (2)O2—C12—C13—C14179.2 (2)
C3—C4—C5—C628.6 (3)C11—C12—C13—C141.3 (4)
C4—C5—C6—C867.4 (3)C10—C9—C14—C133.4 (4)
C4—C5—C6—C153.4 (3)N1—C9—C14—C13179.4 (2)
C4—C5—C6—C7172.1 (2)C12—C13—C14—C92.0 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C14—H14···O1i0.932.393.313 (3)174
N1—H1···I10.862.713.227 (2)120
Symmetry code: (i) x+1, y, z+1.

Experimental details

Crystal data
Chemical formulaC15H18INO2
Mr371.20
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)298
a, b, c (Å)15.922 (5), 10.107 (5), 19.034 (5)
V3)3063 (2)
Z8
Radiation typeMo Kα
µ (mm1)2.09
Crystal size (mm)0.20 × 0.20 × 0.20
Data collection
DiffractometerBruker SMART APEXII area-detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
15382, 3785, 2793
Rint0.025
(sin θ/λ)max1)0.668
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.027, 0.074, 0.93
No. of reflections3785
No. of parameters172
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.46, 0.53

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C14—H14···O1i0.932.393.313 (3)173.7
N1—H1···I10.862.713.227 (2)119.8
Symmetry code: (i) x+1, y, z+1.
 

Acknowledgements

The authors acknowledge the Technology Business Incubator (TBI), CAS in Crystallography, University of Madras, Chennai 600 025, India, for the data collection.

References

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