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

Paramasivam, S.; Bhaskar, G.; Seshadri, P.R.; Perumal, P.T.

doi:10.1107/S1600536812002255

organic compounds

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ISSN: 2056-9890

Volume 68| Part 2| February 2012| Page o506

doi:10.1107/S1600536812002255

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

S. Paramasivam,^a G. Bhaskar,^b P. R. Seshadri ^a ^* and P. T. Perumal ^b

^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 ); 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

Crystal data

C₁₅H₁₈INO₂
M_r = 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)
R_int = 0.025

Refinement

R[F² > 2σ(F²)] = 0.027
wR(F²) = 0.074
S = 0.93
3785 reflections
172 parameters
H-atom parameters constrained
Δρ_max = 0.46 e Å⁻³
Δρ_min = −0.53 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	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 ); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; 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, PLATON and publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812002255/kp2383sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812002255/kp2383Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812002255/kp2383Isup3.cml

checkCIF report

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 Q_T=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.

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

	Fig. 1. The molecular structure of the title compound showing the atom-numbering scheme and displacement ellipsoids drawn at the 30% probability level.
	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

C₁₅H₁₈INO₂	F(000) = 1472
M_r = 371.20	D_x = 1.610 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 3785 reflections
a = 15.922 (5) Å	θ = 2.1–28.3°
b = 10.107 (5) Å	µ = 2.09 mm⁻¹
c = 19.034 (5) Å	T = 298 K
V = 3063 (2) Å³	Block, colourless
Z = 8	0.20 × 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 tube	R_int = 0.025
Graphite monochromator	θ_max = 28.3°, θ_min = 2.1°
ω and ϕ scans	h = −20→21
15382 measured reflections	k = −13→13
3785 independent reflections	l = −18→25

Refinement top

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)] = 0.027	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.074	H-atom parameters constrained
S = 0.93	w = 1/[σ²(F_o²) + (0.0379P)² + 1.6353P] where P = (F_o² + 2F_c²)/3
3785 reflections	(Δ/σ)_max = 0.001
172 parameters	Δρ_max = 0.46 e Å⁻³
0 restraints	Δρ_min = −0.53 e Å⁻³

Crystal data top

C₁₅H₁₈INO₂	V = 3063 (2) Å³
M_r = 371.20	Z = 8
Orthorhombic, Pbca	Mo Kα radiation
a = 15.922 (5) Å	µ = 2.09 mm⁻¹
b = 10.107 (5) Å	T = 298 K
c = 19.034 (5) Å	0.20 × 0.20 × 0.20 mm

Data collection top

Bruker SMART APEXII area-detector diffractometer	2793 reflections with I > 2σ(I)
15382 measured reflections	R_int = 0.025
3785 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.027	0 restraints
wR(F²) = 0.074	H-atom parameters constrained
S = 0.93	Δρ_max = 0.46 e Å⁻³
3785 reflections	Δρ_min = −0.53 e Å⁻³
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

	x	y	z	U_iso*/U_eq
I1	0.423501 (11)	0.337299 (16)	0.478996 (11)	0.05300 (8)
O1	0.52198 (11)	0.14887 (18)	0.37743 (10)	0.0540 (5)
O2	0.07995 (12)	−0.1517 (2)	0.71999 (11)	0.0631 (6)
N1	0.30564 (14)	0.1095 (2)	0.54533 (12)	0.0460 (5)
H1	0.3092	0.1935	0.5520	0.055*
C1	0.45213 (16)	−0.0582 (3)	0.38180 (14)	0.0477 (6)
H1A	0.4938	−0.1126	0.4052	0.057*
H1B	0.4621	−0.0650	0.3317	0.057*
C2	0.46504 (15)	0.0831 (2)	0.40367 (13)	0.0401 (5)
C3	0.40963 (15)	0.1356 (2)	0.45650 (14)	0.0390 (5)
C4	0.35334 (15)	0.0597 (2)	0.49300 (12)	0.0378 (5)
C5	0.34440 (16)	−0.0847 (2)	0.47456 (12)	0.0417 (5)
H5A	0.2873	−0.1125	0.4844	0.050*
H5B	0.3816	−0.1360	0.5044	0.050*
C6	0.36464 (17)	−0.1148 (3)	0.39783 (13)	0.0456 (6)
C7	0.3655 (2)	−0.2658 (3)	0.38817 (17)	0.0698 (9)
H7A	0.3780	−0.2866	0.3401	0.105*
H7B	0.3115	−0.3012	0.4003	0.105*
H7C	0.4076	−0.3039	0.4181	0.105*
C8	0.29981 (18)	−0.0539 (3)	0.34872 (15)	0.0585 (7)
H8A	0.3142	−0.0742	0.3009	0.088*
H8B	0.2990	0.0403	0.3550	0.088*
H8C	0.2453	−0.0895	0.3592	0.088*
C9	0.24994 (15)	0.0393 (2)	0.59096 (12)	0.0381 (5)
C10	0.16832 (16)	0.0851 (2)	0.59962 (13)	0.0424 (5)
H10	0.1502	0.1594	0.5751	0.051*
C11	0.11454 (15)	0.0208 (3)	0.64420 (13)	0.0455 (6)
H11	0.0605	0.0536	0.6508	0.055*
C12	0.13951 (16)	−0.0923 (3)	0.67950 (12)	0.0437 (6)
C13	0.22144 (16)	−0.1371 (3)	0.67234 (13)	0.0437 (6)
H13	0.2393	−0.2119	0.6965	0.052*
C14	0.27628 (15)	−0.0696 (2)	0.62894 (13)	0.0432 (5)
H14	0.3317	−0.0978	0.6252	0.052*
C15	0.1004 (2)	−0.2714 (3)	0.75369 (18)	0.0698 (9)
H15A	0.0528	−0.3020	0.7801	0.105*
H15B	0.1469	−0.2573	0.7849	0.105*
H15C	0.1154	−0.3364	0.7191	0.105*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
I1	0.05114 (12)	0.03804 (11)	0.06982 (15)	−0.00787 (7)	0.00678 (9)	−0.00135 (8)
O1	0.0359 (9)	0.0657 (12)	0.0603 (12)	−0.0075 (8)	0.0092 (9)	0.0037 (9)
O2	0.0516 (12)	0.0801 (16)	0.0577 (12)	−0.0013 (10)	0.0190 (9)	0.0170 (10)
N1	0.0504 (12)	0.0374 (11)	0.0503 (12)	−0.0041 (9)	0.0158 (10)	−0.0014 (9)
C1	0.0425 (13)	0.0544 (15)	0.0463 (14)	0.0056 (12)	0.0054 (12)	−0.0065 (12)
C2	0.0310 (11)	0.0487 (14)	0.0406 (13)	−0.0014 (10)	−0.0019 (10)	0.0016 (11)
C3	0.0388 (12)	0.0349 (12)	0.0432 (13)	−0.0038 (9)	−0.0004 (10)	−0.0004 (10)
C4	0.0368 (12)	0.0384 (12)	0.0381 (12)	−0.0022 (10)	−0.0006 (10)	−0.0005 (10)
C5	0.0459 (14)	0.0373 (12)	0.0419 (13)	−0.0069 (10)	0.0024 (11)	0.0000 (10)
C6	0.0489 (14)	0.0450 (14)	0.0428 (14)	−0.0053 (11)	0.0023 (12)	−0.0077 (11)
C7	0.088 (2)	0.0530 (18)	0.0683 (19)	−0.0100 (17)	0.0057 (18)	−0.0191 (15)
C8	0.0502 (15)	0.075 (2)	0.0503 (16)	−0.0110 (15)	−0.0060 (13)	−0.0034 (14)
C9	0.0406 (12)	0.0369 (11)	0.0370 (12)	−0.0015 (10)	0.0040 (10)	−0.0040 (10)
C10	0.0464 (13)	0.0411 (13)	0.0398 (13)	0.0056 (11)	0.0006 (11)	0.0000 (10)
C11	0.0354 (12)	0.0572 (16)	0.0440 (13)	0.0067 (11)	0.0054 (11)	−0.0043 (12)
C12	0.0440 (13)	0.0552 (15)	0.0318 (12)	−0.0019 (11)	0.0072 (11)	−0.0021 (11)
C13	0.0458 (14)	0.0488 (14)	0.0367 (13)	0.0052 (11)	0.0041 (11)	0.0042 (10)
C14	0.0358 (12)	0.0499 (14)	0.0440 (13)	0.0078 (11)	0.0038 (11)	−0.0008 (11)
C15	0.083 (2)	0.067 (2)	0.0587 (18)	−0.0143 (18)	0.0167 (17)	0.0092 (16)

Geometric parameters (Å, º) top

I1—C3	2.095 (3)	C7—H7A	0.9600
O1—C2	1.230 (3)	C7—H7B	0.9600
O2—C12	1.361 (3)	C7—H7C	0.9600
O2—C15	1.407 (4)	C8—H8A	0.9600
N1—C4	1.350 (3)	C8—H8B	0.9600
N1—C9	1.430 (3)	C8—H8C	0.9600
N1—H1	0.8600	C9—C14	1.382 (3)
C1—C2	1.501 (4)	C9—C10	1.389 (3)
C1—C6	1.537 (4)	C10—C11	1.369 (3)
C1—H1A	0.9700	C10—H10	0.9300
C1—H1B	0.9700	C11—C12	1.385 (4)
C2—C3	1.439 (3)	C11—H11	0.9300
C3—C4	1.369 (3)	C12—C13	1.387 (3)
C4—C5	1.508 (3)	C13—C14	1.382 (3)
C5—C6	1.526 (3)	C13—H13	0.9300
C5—H5A	0.9700	C14—H14	0.9300
C5—H5B	0.9700	C15—H15A	0.9600
C6—C8	1.523 (4)	C15—H15B	0.9600
C6—C7	1.537 (4)	C15—H15C	0.9600

C12—O2—C15	118.4 (2)	C6—C7—H7C	109.5
C4—N1—C9	127.7 (2)	H7A—C7—H7C	109.5
C4—N1—H1	116.1	H7B—C7—H7C	109.5
C9—N1—H1	116.1	C6—C8—H8A	109.5
C2—C1—C6	115.0 (2)	C6—C8—H8B	109.5
C2—C1—H1A	108.5	H8A—C8—H8B	109.5
C6—C1—H1A	108.5	C6—C8—H8C	109.5
C2—C1—H1B	108.5	H8A—C8—H8C	109.5
C6—C1—H1B	108.5	H8B—C8—H8C	109.5
H1A—C1—H1B	107.5	C14—C9—C10	119.1 (2)
O1—C2—C3	122.4 (2)	C14—C9—N1	121.7 (2)
O1—C2—C1	120.2 (2)	C10—C9—N1	119.1 (2)
C3—C2—C1	117.4 (2)	C11—C10—C9	120.0 (2)
C4—C3—C2	123.3 (2)	C11—C10—H10	120.0
C4—C3—I1	120.70 (18)	C9—C10—H10	120.0
C2—C3—I1	115.92 (17)	C10—C11—C12	120.9 (2)
N1—C4—C3	122.3 (2)	C10—C11—H11	119.6
N1—C4—C5	118.7 (2)	C12—C11—H11	119.6
C3—C4—C5	119.1 (2)	O2—C12—C11	116.0 (2)
C4—C5—C6	113.3 (2)	O2—C12—C13	124.5 (2)
C4—C5—H5A	108.9	C11—C12—C13	119.4 (2)
C6—C5—H5A	108.9	C14—C13—C12	119.5 (2)
C4—C5—H5B	108.9	C14—C13—H13	120.3
C6—C5—H5B	108.9	C12—C13—H13	120.3
H5A—C5—H5B	107.7	C9—C14—C13	120.9 (2)
C8—C6—C5	111.3 (2)	C9—C14—H14	119.5
C8—C6—C1	110.0 (2)	C13—C14—H14	119.5
C5—C6—C1	107.9 (2)	O2—C15—H15A	109.5
C8—C6—C7	109.5 (2)	O2—C15—H15B	109.5
C5—C6—C7	108.3 (2)	H15A—C15—H15B	109.5
C1—C6—C7	109.7 (2)	O2—C15—H15C	109.5
C6—C7—H7A	109.5	H15A—C15—H15C	109.5
C6—C7—H7B	109.5	H15B—C15—H15C	109.5
H7A—C7—H7B	109.5

C6—C1—C2—O1	−160.3 (2)	C2—C1—C6—C8	71.8 (3)
C6—C1—C2—C3	20.7 (3)	C2—C1—C6—C5	−49.8 (3)
O1—C2—C3—C4	−171.1 (2)	C2—C1—C6—C7	−167.7 (2)
C1—C2—C3—C4	7.9 (4)	C4—N1—C9—C14	53.2 (4)
O1—C2—C3—I1	6.0 (3)	C4—N1—C9—C10	−129.6 (3)
C1—C2—C3—I1	−174.98 (17)	C14—C9—C10—C11	−1.4 (4)
C9—N1—C4—C3	−174.5 (2)	N1—C9—C10—C11	−178.7 (2)
C9—N1—C4—C5	5.2 (4)	C9—C10—C11—C12	−2.0 (4)
C2—C3—C4—N1	175.8 (2)	C15—O2—C12—C11	176.3 (3)
I1—C3—C4—N1	−1.1 (3)	C15—O2—C12—C13	−4.2 (4)
C2—C3—C4—C5	−3.9 (4)	C10—C11—C12—O2	−177.1 (2)
I1—C3—C4—C5	179.19 (17)	C10—C11—C12—C13	3.3 (4)
N1—C4—C5—C6	151.7 (2)	O2—C12—C13—C14	179.2 (2)
C3—C4—C5—C6	−28.6 (3)	C11—C12—C13—C14	−1.3 (4)
C4—C5—C6—C8	−67.4 (3)	C10—C9—C14—C13	3.4 (4)
C4—C5—C6—C1	53.4 (3)	N1—C9—C14—C13	−179.4 (2)
C4—C5—C6—C7	172.1 (2)	C12—C13—C14—C9	−2.0 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	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.

Experimental details

Crystal data
Chemical formula	C₁₅H₁₈INO₂
M_r	371.20
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	298
a, b, c (Å)	15.922 (5), 10.107 (5), 19.034 (5)
V (Å³)	3063 (2)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	2.09
Crystal size (mm)	0.20 × 0.20 × 0.20

Data collection
Diffractometer	Bruker SMART APEXII area-detector diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	15382, 3785, 2793
R_int	0.025
(sin θ/λ)_max (Å⁻¹)	0.668

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.027, 0.074, 0.93
No. of reflections	3785
No. of parameters	172
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	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···A	D—H	H···A	D···A	D—H···A
C14—H14···O1ⁱ	0.93	2.39	3.313 (3)	173.7
N1—H1···I1	0.86	2.71	3.227 (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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