(1E,4E)-1,5-Bis(2,4-dimethyl­phen­yl)penta-1,4-dien-3-one

Feng, Z.; Li, J.; Lin, Y.

doi:10.1107/S1600536809033583

organic compounds

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ISSN: 2056-9890

Volume 65| Part 9| September 2009| Page o2275

doi:10.1107/S1600536809033583

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(1E,4E)-1,5-Bis(2,4-dimethylphenyl)penta-1,4-dien-3-one

Zhiguo Feng,^a Junhua Li ^b ^* and Yi Lin ^a

^aSchool of Life Science, Anhui Agricultural University, 130 West Yangtze Road, Hefei, Anhui Province 230036, People's Republic of China, and ^bShenzhen Wanxin Pharmatech Co Ltd, 1-108 Bioincubator building, 1st Gaoxin Road, Shenzhen, Guangdong 518057, People's Republic of China
^*Correspondence e-mail: linyi0303@126.com

(Received 14 August 2009; accepted 23 August 2009; online 29 August 2009)

In the title compound, C₂₁H₂₂O, a derivative of the biologically active compound curcumin, the dihedral angle between the aromatic ring planes is 20.57 (11)°.

Related literature

For backgound to cucucmin and its biological properties, see: Began et al. (1999 ); Gautam et al. (2007 ); Liang et al. (2008 ); Liang, Shao et al. (2009 ); Liang, Tian et al. (2007 ); Liang, Yang et al. (2007 ); Liang, Zhou et al. (2009 ); Maheshwari et al. (2006 ); Zhao et al. (2009 ).

Experimental

Crystal data

C₂₁H₂₂O
M_r = 290.39
Monoclinic, P 2₁ /c
a = 4.9548 (7) Å
b = 26.555 (4) Å
c = 12.9632 (19) Å
β = 94.090 (3)°
V = 1701.3 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 293 K
0.42 × 0.37 × 0.26 mm

Data collection

Bruker SMART CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2002 ) T_min = 0.769, T_max = 1.000
8842 measured reflections
3128 independent reflections
2007 reflections with I > 2σ(I)
R_int = 0.095

Refinement

R[F² > 2σ(F²)] = 0.065
wR(F²) = 0.173
S = 0.97
3128 reflections
203 parameters
H-atom parameters constrained
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.21 e Å⁻³

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); 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.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809033583/hb5050sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809033583/hb5050Isup2.hkl

checkCIF report

Comment top

The title compound, C₂₁H₂₂O, (1E,4E)-1,5-bis(2,4-dimethylphenyl)penta-1,4-dien-3-one (I), is a mono-carbonyl analogue of curcumin. Curcumin has been found to possess a variety of pharmaceutical applications, for example, inhibiting the mutations and the formation of tumors, antioxidation, anti-inflammation and anti-virus (Began et al., 1999; Maheshwari et al., 2006; Gautam et al., 2007). According to the structural disadvantages of curcumin which is considered to be responsible for its weak pharmacokinetic profiles, a series of mono-carbonyl analogues have been designed and synthesized, and their biological activity in vitro and in vivo were evaluated.

Derivatives of dibenzylidene acetone, cyclopentanone and cyclohexanone exhibit potent anti-inflammatory, antibacterial and anti-cancer activity.(Liang et al., 2008; Liang et al., 2008; Liang, Shao et al., 2009; Liang, Zhou et al., 2009). This fact leads to the significance of these synthetic mono-carbonyl analogues of curcumin. Several of these derivatives have been reported their crystal structures (Liang, Tian et al., 2007; Liang, Yang et al., 2007; Zhao et al., 2009). In the present paper, we describe the crystal structure of the title compound C₂₁H₂₂O (I) here. Its geometrical parameters of are normal, the dihedral angle between the six-membered aromatic ring planes is 20.57 (11)°.

Related literature top

For backgound to cucucmin and its biological properties, see: Began et al. (1999); Gautam et al. (2007); Liang et al. (2008); Liang, Shao et al. (2009); Liang, Tian et al. (2007); Liang, Yang et al.(2007); Liang, Zhou et al. (2009); Maheshwari et al. (2006); Zhao et al. (2009).

Experimental top

To a solution of 15 mmol 2,4-dimethylbenzaldehyde in MeOH (10 ml) was added 7.5 mmol acetone. The solution was stirred at room temperature for 20 min, followed by added dropwise 20% (w/v) NaOH (1.5 ml, 7.5 mmol). The mixture was stirred at RT and monitored with TLC. When the reaction finished, the residue was poured into saturated NH₄Cl solution and filtered. The precipitate was washed and purified by chromatography over silica gel using CH₂Cl₂ / CH₃OH as the eluent to afford the pure product (yield: 38.2%). Colourless blokcs of (I) were grown in a CH₂Cl₂—CH₃OH mixture (6:2 v/v) by slow evaporation (mp 436–437 K). 1H-NMR (CDCl₃): 2.34 (s, 6H, Ar₄—CH₃), 2.44 (s, 6H, Ar₂—CH₃), 6.96 (d, 2H, J=16.0 Hz, =CH—C=O), 7.05 (m, 4H, Ar—H₃,₅), 7.56 (d, 2H, J=8.0 Hz, Ar—H₆), 8.0 (d, 2H, J=16.0 Hz, Ar—CH=C). ESI-MS m/z: 603.8 (2M+Na)+, calcd for C₂₁H₂₂O: 290.4.

Computing details top

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); 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 (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of (I) shoiwng 50% displacement ellipsoids for the non-hydrogen atoms.

(1E,4E)-1,5-Bis(2,4-dimethylphenyl)penta-1,4-dien-3-one top

Crystal data top

C₂₁H₂₂O	F(000) = 624
M_r = 290.39	D_x = 1.134 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 1845 reflections
a = 4.9548 (7) Å	θ = 4.4–44.1°
b = 26.555 (4) Å	µ = 0.07 mm⁻¹
c = 12.9632 (19) Å	T = 293 K
β = 94.090 (3)°	Prism, green
V = 1701.3 (4) Å³	0.42 × 0.37 × 0.26 mm
Z = 4

Data collection top

Bruker SMART CCD diffractometer	3128 independent reflections
Radiation source: fine-focus sealed tube	2007 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.095
ω scans	θ_max = 25.5°, θ_min = 1.5°
Absorption correction: multi-scan (SADABS; Bruker, 2002)	h = −5→6
T_min = 0.769, T_max = 1.000	k = −31→32
8842 measured reflections	l = −7→15

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)] = 0.065	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.173	H-atom parameters constrained
S = 0.97	w = 1/[σ²(F_o²) + (0.0858P)²] where P = (F_o² + 2F_c²)/3
3128 reflections	(Δ/σ)_max = 0.057
203 parameters	Δρ_max = 0.21 e Å⁻³
0 restraints	Δρ_min = −0.21 e Å⁻³

Crystal data top

C₂₁H₂₂O	V = 1701.3 (4) Å³
M_r = 290.39	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 4.9548 (7) Å	µ = 0.07 mm⁻¹
b = 26.555 (4) Å	T = 293 K
c = 12.9632 (19) Å	0.42 × 0.37 × 0.26 mm
β = 94.090 (3)°

Data collection top

Bruker SMART CCD diffractometer	3128 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2002)	2007 reflections with I > 2σ(I)
T_min = 0.769, T_max = 1.000	R_int = 0.095
8842 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.065	0 restraints
wR(F²) = 0.173	H-atom parameters constrained
S = 0.97	Δρ_max = 0.21 e Å⁻³
3128 reflections	Δρ_min = −0.21 e Å⁻³
203 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
O1	1.4353 (4)	0.35616 (7)	0.08357 (12)	0.0700 (5)
C1	1.2047 (5)	0.36963 (8)	0.09662 (16)	0.0510 (6)
C2	1.0758 (5)	0.35782 (8)	0.19171 (16)	0.0528 (6)
H2	0.9031	0.3703	0.1994	0.063*
C3	1.1920 (4)	0.33037 (8)	0.26714 (16)	0.0479 (6)
H3	1.3621	0.3173	0.2566	0.057*
C4	1.0435 (5)	0.39838 (8)	0.01739 (16)	0.0545 (6)
H4	0.8698	0.4083	0.0313	0.065*
C5	1.1329 (5)	0.41070 (8)	−0.07216 (16)	0.0516 (6)
H5	1.3019	0.3982	−0.0860	0.062*
C6	0.9942 (4)	0.44212 (7)	−0.15263 (16)	0.0473 (6)
C7	1.0565 (4)	0.43873 (7)	−0.25633 (16)	0.0493 (6)
C8	0.9237 (5)	0.47084 (8)	−0.32771 (17)	0.0557 (6)
H8	0.9633	0.4684	−0.3966	0.067*
C9	0.7367 (5)	0.50614 (8)	−0.30192 (18)	0.0570 (6)
C10	0.6759 (5)	0.50852 (9)	−0.19985 (19)	0.0645 (7)
H10	0.5482	0.5316	−0.1801	0.077*
C11	0.8023 (5)	0.47709 (9)	−0.12683 (18)	0.0603 (6)
H11	0.7577	0.4794	−0.0585	0.072*
C12	1.0812 (4)	0.31833 (7)	0.36552 (15)	0.0455 (5)
C13	0.8956 (5)	0.34978 (8)	0.40688 (17)	0.0564 (6)
H13	0.8429	0.3789	0.3710	0.068*
C14	0.7855 (5)	0.33986 (9)	0.49876 (18)	0.0614 (7)
H14	0.6607	0.3620	0.5239	0.074*
C15	0.8597 (5)	0.29692 (9)	0.55428 (16)	0.0544 (6)
C16	1.0474 (4)	0.26532 (9)	0.51378 (16)	0.0535 (6)
H16	1.0998	0.2365	0.5506	0.064*
C17	1.1613 (4)	0.27453 (8)	0.42090 (15)	0.0466 (5)
C18	1.2581 (5)	0.40116 (8)	−0.29188 (17)	0.0626 (7)
H18A	1.2595	0.4025	−0.3658	0.094*
H18B	1.2081	0.3679	−0.2712	0.094*
H18C	1.4350	0.4091	−0.2613	0.094*
C19	0.5986 (6)	0.54084 (9)	−0.3819 (2)	0.0795 (8)
H19A	0.6863	0.5383	−0.4453	0.119*
H19B	0.6098	0.5749	−0.3572	0.119*
H19C	0.4120	0.5313	−0.3938	0.119*
C20	1.3587 (5)	0.23772 (9)	0.38199 (18)	0.0640 (7)
H20A	1.3890	0.2110	0.4313	0.096*
H20B	1.5267	0.2545	0.3725	0.096*
H20C	1.2871	0.2240	0.3172	0.096*
C21	0.7377 (5)	0.28438 (12)	0.65406 (18)	0.0784 (8)
H21A	0.6361	0.3127	0.6761	0.118*
H21B	0.8792	0.2765	0.7060	0.118*
H21C	0.6198	0.2559	0.6438	0.118*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0565 (11)	0.0924 (13)	0.0619 (11)	0.0062 (9)	0.0100 (9)	0.0172 (9)
C1	0.0505 (14)	0.0541 (13)	0.0482 (13)	−0.0077 (11)	0.0023 (11)	0.0032 (10)
C2	0.0491 (13)	0.0618 (14)	0.0476 (13)	−0.0010 (11)	0.0044 (11)	0.0058 (11)
C3	0.0476 (13)	0.0479 (12)	0.0482 (13)	−0.0034 (10)	0.0043 (10)	−0.0009 (10)
C4	0.0522 (14)	0.0625 (14)	0.0492 (13)	0.0007 (11)	0.0061 (11)	0.0072 (11)
C5	0.0558 (14)	0.0491 (13)	0.0498 (13)	−0.0050 (10)	0.0036 (11)	−0.0002 (10)
C6	0.0546 (14)	0.0411 (11)	0.0459 (13)	−0.0053 (10)	0.0016 (10)	−0.0001 (9)
C7	0.0548 (13)	0.0456 (12)	0.0474 (13)	−0.0087 (10)	0.0037 (11)	0.0022 (10)
C8	0.0668 (16)	0.0528 (13)	0.0474 (13)	−0.0088 (12)	0.0034 (11)	0.0045 (11)
C9	0.0682 (16)	0.0427 (12)	0.0588 (15)	−0.0048 (12)	−0.0049 (12)	0.0009 (11)
C10	0.0678 (17)	0.0532 (14)	0.0716 (17)	0.0092 (12)	−0.0008 (13)	−0.0069 (13)
C11	0.0715 (17)	0.0579 (14)	0.0520 (14)	−0.0001 (12)	0.0084 (12)	−0.0018 (11)
C12	0.0447 (12)	0.0481 (12)	0.0435 (12)	−0.0012 (10)	0.0020 (10)	−0.0009 (10)
C13	0.0607 (15)	0.0549 (13)	0.0539 (14)	0.0141 (11)	0.0074 (12)	0.0058 (11)
C14	0.0598 (15)	0.0696 (16)	0.0564 (15)	0.0172 (13)	0.0156 (12)	0.0002 (12)
C15	0.0517 (14)	0.0657 (15)	0.0461 (13)	0.0025 (12)	0.0056 (11)	0.0027 (11)
C16	0.0531 (14)	0.0586 (14)	0.0487 (13)	0.0035 (11)	0.0031 (11)	0.0115 (11)
C17	0.0455 (12)	0.0462 (12)	0.0479 (13)	0.0023 (10)	0.0015 (10)	0.0012 (10)
C18	0.0700 (16)	0.0639 (15)	0.0549 (14)	0.0062 (13)	0.0110 (12)	−0.0017 (12)
C19	0.095 (2)	0.0616 (16)	0.0795 (19)	0.0047 (14)	−0.0140 (16)	0.0103 (14)
C20	0.0720 (17)	0.0580 (14)	0.0632 (15)	0.0108 (13)	0.0140 (13)	0.0003 (12)
C21	0.0716 (18)	0.107 (2)	0.0586 (16)	0.0085 (16)	0.0199 (13)	0.0149 (15)

Geometric parameters (Å, º) top

O1—C1	1.221 (3)	C12—C17	1.409 (3)
C1—C2	1.462 (3)	C13—C14	1.370 (3)
C1—C4	1.469 (3)	C13—H13	0.9300
C2—C3	1.319 (3)	C14—C15	1.384 (3)
C2—H2	0.9300	C14—H14	0.9300
C3—C12	1.459 (3)	C15—C16	1.383 (3)
C3—H3	0.9300	C15—C21	1.504 (3)
C4—C5	1.313 (3)	C16—C17	1.388 (3)
C4—H4	0.9300	C16—H16	0.9300
C5—C6	1.468 (3)	C17—C20	1.496 (3)
C5—H5	0.9300	C18—H18A	0.9600
C6—C11	1.387 (3)	C18—H18B	0.9600
C6—C7	1.403 (3)	C18—H18C	0.9600
C7—C8	1.389 (3)	C19—H19A	0.9600
C7—C18	1.507 (3)	C19—H19B	0.9600
C8—C9	1.376 (3)	C19—H19C	0.9600
C8—H8	0.9300	C20—H20A	0.9600
C9—C10	1.379 (3)	C20—H20B	0.9600
C9—C19	1.513 (3)	C20—H20C	0.9600
C10—C11	1.379 (3)	C21—H21A	0.9601
C10—H10	0.9300	C21—H21B	0.9601
C11—H11	0.9300	C21—H21C	0.9601
C12—C13	1.379 (3)

O1—C1—C2	121.6 (2)	C12—C13—H13	118.7
O1—C1—C4	121.5 (2)	C13—C14—C15	120.2 (2)
C2—C1—C4	116.9 (2)	C13—C14—H14	119.9
C3—C2—C1	123.4 (2)	C15—C14—H14	119.9
C3—C2—H2	118.3	C14—C15—C16	117.6 (2)
C1—C2—H2	118.3	C14—C15—C21	121.4 (2)
C2—C3—C12	126.7 (2)	C16—C15—C21	121.0 (2)
C2—C3—H3	116.6	C15—C16—C17	123.3 (2)
C12—C3—H3	116.7	C15—C16—H16	118.4
C5—C4—C1	123.1 (2)	C17—C16—H16	118.4
C5—C4—H4	118.4	C16—C17—C12	118.1 (2)
C1—C4—H4	118.4	C16—C17—C20	119.59 (19)
C4—C5—C6	126.8 (2)	C12—C17—C20	122.3 (2)
C4—C5—H5	116.6	C7—C18—H18A	109.5
C6—C5—H5	116.6	C7—C18—H18B	109.5
C11—C6—C7	118.4 (2)	H18A—C18—H18B	109.5
C11—C6—C5	120.2 (2)	C7—C18—H18C	109.5
C7—C6—C5	121.4 (2)	H18A—C18—H18C	109.5
C8—C7—C6	118.2 (2)	H18B—C18—H18C	109.5
C8—C7—C18	119.7 (2)	C9—C19—H19A	109.5
C6—C7—C18	122.09 (19)	C9—C19—H19B	109.5
C9—C8—C7	123.5 (2)	H19A—C19—H19B	109.5
C9—C8—H8	118.3	C9—C19—H19C	109.5
C7—C8—H8	118.3	H19A—C19—H19C	109.5
C8—C9—C10	117.5 (2)	H19B—C19—H19C	109.5
C8—C9—C19	121.9 (2)	C17—C20—H20A	109.5
C10—C9—C19	120.7 (2)	C17—C20—H20B	109.5
C11—C10—C9	120.8 (2)	H20A—C20—H20B	109.5
C11—C10—H10	119.6	C17—C20—H20C	109.5
C9—C10—H10	119.6	H20A—C20—H20C	109.5
C10—C11—C6	121.7 (2)	H20B—C20—H20C	109.5
C10—C11—H11	119.2	C15—C21—H21A	109.5
C6—C11—H11	119.1	C15—C21—H21B	109.5
C13—C12—C17	118.2 (2)	H21A—C21—H21B	109.5
C13—C12—C3	120.67 (19)	C15—C21—H21C	109.5
C17—C12—C3	121.08 (19)	H21A—C21—H21C	109.5
C14—C13—C12	122.6 (2)	H21B—C21—H21C	109.5
C14—C13—H13	118.7

O1—C1—C2—C3	−3.1 (3)	C9—C10—C11—C6	0.1 (4)
C4—C1—C2—C3	176.8 (2)	C7—C6—C11—C10	−0.8 (3)
C1—C2—C3—C12	177.8 (2)	C5—C6—C11—C10	177.5 (2)
O1—C1—C4—C5	1.1 (4)	C2—C3—C12—C13	−26.1 (3)
C2—C1—C4—C5	−178.8 (2)	C2—C3—C12—C17	154.2 (2)
C1—C4—C5—C6	−175.49 (19)	C17—C12—C13—C14	−0.5 (3)
C4—C5—C6—C11	24.6 (3)	C3—C12—C13—C14	179.7 (2)
C4—C5—C6—C7	−157.2 (2)	C12—C13—C14—C15	0.1 (4)
C11—C6—C7—C8	0.4 (3)	C13—C14—C15—C16	0.4 (4)
C5—C6—C7—C8	−177.83 (18)	C13—C14—C15—C21	−178.5 (2)
C11—C6—C7—C18	−178.7 (2)	C14—C15—C16—C17	−0.4 (3)
C5—C6—C7—C18	3.0 (3)	C21—C15—C16—C17	178.4 (2)
C6—C7—C8—C9	0.7 (3)	C15—C16—C17—C12	0.1 (3)
C18—C7—C8—C9	179.9 (2)	C15—C16—C17—C20	−178.8 (2)
C7—C8—C9—C10	−1.4 (3)	C13—C12—C17—C16	0.4 (3)
C7—C8—C9—C19	179.3 (2)	C3—C12—C17—C16	−179.83 (19)
C8—C9—C10—C11	1.0 (4)	C13—C12—C17—C20	179.2 (2)
C19—C9—C10—C11	−179.7 (2)	C3—C12—C17—C20	−1.0 (3)

Experimental details

Crystal data
Chemical formula	C₂₁H₂₂O
M_r	290.39
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	4.9548 (7), 26.555 (4), 12.9632 (19)
β (°)	94.090 (3)
V (Å³)	1701.3 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.07
Crystal size (mm)	0.42 × 0.37 × 0.26

Data collection
Diffractometer	Bruker SMART CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2002)
T_min, T_max	0.769, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	8842, 3128, 2007
R_int	0.095
(sin θ/λ)_max (Å⁻¹)	0.606

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.065, 0.173, 0.97
No. of reflections	3128
No. of parameters	203
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.21, −0.21

Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

This work was supported by the Key Sci&Tech Project of Wenzhou Government (grant No. 2008S0629).

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