2,6-Bis(2,4-dichloro­benzyl­idene)cyclo­hexa­none

Abstract

The title compound, C₂₀H₁₄Cl₄O, was prepared from a mixture of 2,4-dichloro­benzophenone and cyclo­hexa­none. The dihedral angles formed by the cyclohexane ring and two benzene rings are 39.18 (2) and 60.72 (2)°. There are some weak intra­molecular C—H⋯O and C—H⋯Cl hydrogen-bond contacts in the crystal structure.

Related literature

For related literature, see: Butcher et al. (2006 ▶); Deli et al. (1984 ▶); Jia et al. (1989 ▶); Yu et al. (2000 ▶).

Experimental

Crystal data

• C₂₀H₁₄Cl₄O

• M _r = 412.11

• Orthorhombic,

• a = 14.469 (2) Å

• b = 8.0602 (12) Å

• c = 31.554 (4) Å

• V = 3679.9 (9) ų

• Z = 8

• Mo Kα radiation

• μ = 0.65 mm⁻¹

• T = 293 (2) K

• 0.20 × 0.15 × 0.10 mm

Data collection

• Bruker SMART CCD area-detector diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 1997 ▶) T _min = 0.881, T _max = 0.938

• 21985 measured reflections

• 4570 independent reflections

• 2735 reflections with I > 2σ(I)

• R _int = 0.053

Refinement

• R[F ² > 2σ(F ²)] = 0.050

• wR(F ²) = 0.118

• S = 1.03

• 4570 reflections

• 226 parameters

• H-atom parameters constrained

• Δρ_max = 0.24 e Å⁻³

• Δρ_min = −0.28 e Å⁻³

Data collection: SMART (Bruker, 1997 ▶); cell refinement: SAINT (Bruker, 1997 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C7—H7A⋯Cl2	0.93	2.74	3.055 (2)	101
C7—H7A⋯O1	0.93	2.33	2.732 (3)	105
C14—H14A⋯O1	0.93	2.39	2.759 (3)	103

supplementary crystallographic information

Comment

As useful precursors to potentially bioactive pyrimidine derivatives, a,a-bis(substituted benzylidene) cycloalkanones have attracted considerable attention for many years (Deli et al., 1984). In recent years, a series of non-linear optically active bis(benzylidene) ketones have been synthesized (Yu et al., 2000). As part of our search for new non-linear optically active compounds, we synthesized the title compound (I), and describe its structure here.

In the structure of (I) (Fig. 1), all of the bond lengthes and bond angles fall in the normal range (Yu et al., 2000; Jia et al., 1989; Butcher et al., 2006). There are some weak C—H···O and C—H···Cl intramolecular hydrogen bonds in the crystal structure.

Experimental

A mixture of the 2,4-dichlorobenzophenone (0.2 mol), and cyclohexanone (0.1 mol) and 10% NaOH (10 ml) was stirred in ethanol (30 mL) for 5 h to afford the title compound [yield: 82%]. Single crystals suitable for X-ray measurements were obtained by recrystallization from ethanol at room temperature.

Refinement

H atoms were fixed geometrically and allowed to ride on their attached atoms, with C—H = 0.93–0.97 Å, and with U_iso(H) = 1.2U_eq(C).

Figures

Fig. 1.

The structure of the title compound, showing 30% probability displacement ellipsoids and the atom-numbering scheme.

Crystal data

C20H14Cl4O	Z = 8
Mr = 412.11	F000 = 1680
Orthorhombic, Pbca	Dx = 1.488 Mg m−3
Hall symbol: -P 2ac 2ab	Mo Kα radiation λ = 0.71073 Å
a = 14.469 (2) Å	µ = 0.65 mm−1
b = 8.0602 (12) Å	T = 293 (2) K
c = 31.554 (4) Å	Bar, yellow
V = 3679.9 (9) Å3	0.20 × 0.15 × 0.10 mm

Data collection

Bruker SMART CCD area-detector diffractometer	4570 independent reflections
Radiation source: fine-focus sealed tube	2735 reflections with I > 2σ(I)
Monochromator: graphite	Rint = 0.053
T = 293(2) K	θmax = 28.4º
φ and ω scans	θmin = 1.3º
Absorption correction: multi-scan(SADABS; Bruker, 1997)	h = −19→18
Tmin = 0.881, Tmax = 0.938	k = −10→10
21985 measured reflections	l = −19→42

Refinement

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)] = 0.050	H-atom parameters constrained
wR(F2) = 0.118	w = 1/[σ2(Fo2) + (0.0381P)2 + 1.6278P] where P = (Fo2 + 2Fc2)/3
S = 1.03	(Δ/σ)max = 0.001
4570 reflections	Δρmax = 0.24 e Å−3
226 parameters	Δρmin = −0.28 e Å−3
Primary atom site location: structure-invariant direct methods	Extinction correction: none

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Cl1	−0.37152 (7)	0.07869 (15)	−0.49524 (3)	0.1044 (4)
Cl2	−0.51233 (4)	0.04759 (9)	−0.33808 (2)	0.05594 (19)
Cl3	0.06595 (6)	0.60906 (12)	−0.04572 (3)	0.0852 (3)
Cl4	−0.21635 (6)	0.20911 (12)	−0.08713 (2)	0.0825 (3)
O1	−0.36351 (10)	0.3253 (2)	−0.22630 (5)	0.0557 (5)
C1	−0.42738 (15)	0.1234 (3)	−0.37207 (8)	0.0468 (6)
C2	−0.43315 (18)	0.0787 (4)	−0.41435 (8)	0.0578 (7)
H2A	−0.4804	0.0098	−0.4238	0.069*
C3	−0.36783 (19)	0.1381 (4)	−0.44228 (9)	0.0635 (8)
C4	−0.29917 (19)	0.2442 (4)	−0.42879 (9)	0.0663 (8)
H4A	−0.2572	0.2881	−0.4481	0.080*
C5	−0.29343 (17)	0.2844 (4)	−0.38653 (9)	0.0592 (7)
H5A	−0.2465	0.3550	−0.3776	0.071*
C6	−0.35581 (16)	0.2229 (3)	−0.35643 (8)	0.0466 (6)
C7	−0.34846 (15)	0.2620 (3)	−0.31106 (8)	0.0461 (6)
H7A	−0.4041	0.2752	−0.2967	0.055*
C8	−0.27162 (14)	0.2811 (3)	−0.28761 (8)	0.0419 (6)
C9	−0.17413 (14)	0.2600 (3)	−0.30424 (8)	0.0499 (6)
H9A	−0.1571	0.3581	−0.3202	0.060*
H9B	−0.1727	0.1661	−0.3235	0.060*
C10	−0.10328 (15)	0.2324 (3)	−0.26939 (8)	0.0502 (6)
H10A	−0.1142	0.1261	−0.2559	0.060*
H10B	−0.0417	0.2310	−0.2815	0.060*
C11	−0.11002 (15)	0.3693 (3)	−0.23677 (8)	0.0457 (6)
H11A	−0.0612	0.3563	−0.2160	0.055*
H11B	−0.1020	0.4760	−0.2505	0.055*
C12	−0.20266 (14)	0.3642 (3)	−0.21491 (8)	0.0412 (5)
C13	−0.28552 (15)	0.3230 (3)	−0.24158 (7)	0.0423 (6)
C14	−0.21556 (16)	0.3858 (3)	−0.17333 (8)	0.0466 (6)
H14A	−0.2751	0.3680	−0.1632	0.056*
C15	−0.14545 (15)	0.4349 (3)	−0.14198 (8)	0.0443 (6)
C16	−0.08247 (16)	0.5614 (3)	−0.15088 (8)	0.0512 (6)
H16A	−0.0840	0.6112	−0.1775	0.061*
C17	−0.01834 (18)	0.6150 (3)	−0.12186 (8)	0.0554 (7)
H17A	0.0227	0.6995	−0.1288	0.067*
C18	−0.01524 (17)	0.5426 (3)	−0.08242 (8)	0.0539 (7)
C19	−0.07653 (18)	0.4177 (3)	−0.07173 (8)	0.0555 (7)
H19A	−0.0746	0.3691	−0.0450	0.067*
C20	−0.14056 (17)	0.3665 (3)	−0.10137 (8)	0.0490 (6)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Cl1	0.1071 (7)	0.1580 (10)	0.0482 (5)	−0.0068 (7)	0.0000 (5)	−0.0108 (5)
Cl2	0.0381 (3)	0.0687 (4)	0.0610 (4)	−0.0027 (3)	0.0010 (3)	0.0002 (3)
Cl3	0.0747 (5)	0.1149 (7)	0.0660 (5)	−0.0291 (5)	−0.0131 (4)	−0.0144 (5)
Cl4	0.0959 (6)	0.0945 (6)	0.0572 (5)	−0.0482 (5)	−0.0024 (4)	0.0122 (4)
O1	0.0313 (9)	0.0847 (14)	0.0509 (10)	−0.0009 (8)	0.0073 (8)	0.0041 (10)
C1	0.0355 (13)	0.0554 (16)	0.0497 (15)	0.0080 (11)	−0.0013 (11)	0.0045 (12)
C2	0.0506 (16)	0.0682 (19)	0.0546 (17)	0.0054 (13)	−0.0080 (13)	−0.0023 (14)
C3	0.0559 (17)	0.090 (2)	0.0445 (15)	0.0099 (16)	−0.0043 (14)	−0.0017 (15)
C4	0.0524 (16)	0.093 (2)	0.0531 (17)	0.0033 (16)	0.0063 (14)	0.0141 (16)
C5	0.0459 (15)	0.077 (2)	0.0549 (17)	−0.0076 (13)	−0.0001 (13)	0.0080 (15)
C6	0.0355 (12)	0.0555 (15)	0.0488 (15)	0.0069 (11)	−0.0019 (11)	0.0027 (12)
C7	0.0335 (12)	0.0547 (15)	0.0501 (15)	0.0002 (10)	0.0026 (11)	0.0034 (12)
C8	0.0331 (12)	0.0459 (14)	0.0468 (14)	−0.0012 (10)	0.0041 (10)	0.0056 (11)
C9	0.0331 (12)	0.0648 (17)	0.0517 (15)	−0.0026 (11)	0.0061 (11)	−0.0020 (13)
C10	0.0318 (12)	0.0576 (16)	0.0612 (16)	0.0049 (11)	0.0045 (12)	−0.0007 (13)
C11	0.0316 (12)	0.0537 (15)	0.0518 (15)	−0.0006 (11)	−0.0006 (11)	0.0023 (12)
C12	0.0327 (12)	0.0436 (14)	0.0473 (14)	0.0007 (10)	0.0024 (11)	0.0048 (11)
C13	0.0331 (12)	0.0458 (14)	0.0481 (14)	0.0018 (10)	0.0034 (11)	0.0096 (11)
C14	0.0340 (12)	0.0552 (15)	0.0507 (15)	−0.0003 (11)	0.0016 (11)	0.0050 (12)
C15	0.0370 (12)	0.0527 (15)	0.0431 (14)	0.0021 (11)	0.0027 (11)	−0.0019 (12)
C16	0.0490 (14)	0.0575 (16)	0.0471 (15)	−0.0007 (12)	0.0020 (12)	0.0047 (13)
C17	0.0513 (15)	0.0566 (17)	0.0583 (17)	−0.0101 (13)	0.0042 (13)	−0.0005 (14)
C18	0.0484 (14)	0.0633 (17)	0.0499 (16)	−0.0018 (13)	−0.0033 (12)	−0.0111 (14)
C19	0.0629 (17)	0.0642 (18)	0.0393 (14)	−0.0059 (14)	−0.0008 (12)	−0.0001 (13)
C20	0.0487 (14)	0.0513 (16)	0.0469 (15)	−0.0062 (12)	0.0052 (12)	−0.0013 (12)

Geometric parameters (Å, °)

Cl1—C3	1.739 (3)	C9—H9B	0.9700
Cl2—C1	1.742 (2)	C10—C11	1.512 (3)
Cl3—C18	1.735 (3)	C10—H10A	0.9700
Cl4—C20	1.736 (3)	C10—H10B	0.9700
O1—C13	1.227 (2)	C11—C12	1.508 (3)
C1—C2	1.384 (3)	C11—H11A	0.9700
C1—C6	1.400 (3)	C11—H11B	0.9700
C2—C3	1.378 (4)	C12—C14	1.337 (3)
C2—H2A	0.9300	C12—C13	1.502 (3)
C3—C4	1.378 (4)	C14—C15	1.471 (3)
C4—C5	1.375 (4)	C14—H14A	0.9300
C4—H4A	0.9300	C15—C16	1.396 (3)
C5—C6	1.401 (3)	C15—C20	1.397 (3)
C5—H5A	0.9300	C16—C17	1.373 (3)
C6—C7	1.470 (3)	C16—H16A	0.9300
C7—C8	1.345 (3)	C17—C18	1.375 (4)
C7—H7A	0.9300	C17—H17A	0.9300
C8—C13	1.504 (3)	C18—C19	1.383 (4)
C8—C9	1.515 (3)	C19—C20	1.380 (3)
C9—C10	1.520 (3)	C19—H19A	0.9300
C9—H9A	0.9700
C2—C1—C6	122.2 (2)	H10A—C10—H10B	108.2
C2—C1—Cl2	117.4 (2)	C12—C11—C10	110.4 (2)
C6—C1—Cl2	120.4 (2)	C12—C11—H11A	109.6
C3—C2—C1	119.0 (3)	C10—C11—H11A	109.6
C3—C2—H2A	120.5	C12—C11—H11B	109.6
C1—C2—H2A	120.5	C10—C11—H11B	109.6
C2—C3—C4	120.8 (3)	H11A—C11—H11B	108.1
C2—C3—Cl1	119.9 (2)	C14—C12—C13	117.9 (2)
C4—C3—Cl1	119.3 (2)	C14—C12—C11	124.7 (2)
C5—C4—C3	119.3 (3)	C13—C12—C11	117.3 (2)
C5—C4—H4A	120.3	O1—C13—C12	120.7 (2)
C3—C4—H4A	120.3	O1—C13—C8	120.4 (2)
C4—C5—C6	122.4 (3)	C12—C13—C8	118.93 (19)
C4—C5—H5A	118.8	C12—C14—C15	126.8 (2)
C6—C5—H5A	118.8	C12—C14—H14A	116.6
C1—C6—C5	116.1 (2)	C15—C14—H14A	116.6
C1—C6—C7	121.3 (2)	C16—C15—C20	116.1 (2)
C5—C6—C7	122.5 (2)	C16—C15—C14	120.7 (2)
C8—C7—C6	128.4 (2)	C20—C15—C14	123.1 (2)
C8—C7—H7A	115.8	C17—C16—C15	122.5 (2)
C6—C7—H7A	115.8	C17—C16—H16A	118.8
C7—C8—C13	116.5 (2)	C15—C16—H16A	118.8
C7—C8—C9	124.5 (2)	C16—C17—C18	119.5 (2)
C13—C8—C9	118.96 (19)	C16—C17—H17A	120.3
C8—C9—C10	113.2 (2)	C18—C17—H17A	120.3
C8—C9—H9A	108.9	C17—C18—C19	120.6 (2)
C10—C9—H9A	108.9	C17—C18—Cl3	119.7 (2)
C8—C9—H9B	108.9	C19—C18—Cl3	119.8 (2)
C10—C9—H9B	108.9	C20—C19—C18	118.9 (2)
H9A—C9—H9B	107.8	C20—C19—H19A	120.6
C11—C10—C9	110.0 (2)	C18—C19—H19A	120.6
C11—C10—H10A	109.7	C19—C20—C15	122.5 (2)
C9—C10—H10A	109.7	C19—C20—Cl4	117.9 (2)
C11—C10—H10B	109.7	C15—C20—Cl4	119.59 (19)
C9—C10—H10B	109.7
C6—C1—C2—C3	−1.9 (4)	C11—C12—C13—O1	−176.1 (2)
Cl2—C1—C2—C3	179.2 (2)	C14—C12—C13—C8	−173.9 (2)
C1—C2—C3—C4	−1.9 (4)	C11—C12—C13—C8	3.0 (3)
C1—C2—C3—Cl1	178.0 (2)	C7—C8—C13—O1	5.7 (3)
C2—C3—C4—C5	3.2 (4)	C9—C8—C13—O1	−173.0 (2)
Cl1—C3—C4—C5	−176.7 (2)	C7—C8—C13—C12	−173.4 (2)
C3—C4—C5—C6	−0.8 (4)	C9—C8—C13—C12	7.9 (3)
C2—C1—C6—C5	4.1 (4)	C13—C12—C14—C15	−176.6 (2)
Cl2—C1—C6—C5	−176.99 (19)	C11—C12—C14—C15	6.7 (4)
C2—C1—C6—C7	−176.9 (2)	C12—C14—C15—C16	43.5 (4)
Cl2—C1—C6—C7	1.9 (3)	C12—C14—C15—C20	−140.1 (3)
C4—C5—C6—C1	−2.8 (4)	C20—C15—C16—C17	0.8 (4)
C4—C5—C6—C7	178.3 (3)	C14—C15—C16—C17	177.5 (2)
C1—C6—C7—C8	145.0 (3)	C15—C16—C17—C18	0.0 (4)
C5—C6—C7—C8	−36.1 (4)	C16—C17—C18—C19	−0.5 (4)
C6—C7—C8—C13	179.4 (2)	C16—C17—C18—Cl3	179.7 (2)
C6—C7—C8—C9	−2.0 (4)	C17—C18—C19—C20	0.3 (4)
C7—C8—C9—C10	−161.0 (2)	Cl3—C18—C19—C20	−180.0 (2)
C13—C8—C9—C10	17.6 (3)	C18—C19—C20—C15	0.6 (4)
C8—C9—C10—C11	−53.5 (3)	C18—C19—C20—Cl4	179.8 (2)
C9—C10—C11—C12	64.1 (3)	C16—C15—C20—C19	−1.1 (4)
C10—C11—C12—C14	138.1 (3)	C14—C15—C20—C19	−177.7 (2)
C10—C11—C12—C13	−38.5 (3)	C16—C15—C20—Cl4	179.69 (18)
C14—C12—C13—O1	7.0 (4)	C14—C15—C20—Cl4	3.1 (3)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7A···Cl2	0.93	2.74	3.055 (2)	101
C7—H7A···O1	0.93	2.33	2.732 (3)	105
C14—H14A···O1	0.93	2.39	2.759 (3)	103