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Acta Cryst. (2013). E69, o111    [ doi:10.1107/S1600536812050349 ]

(E)-16-(4-Chlorobenzylidene)estrone

J. Suresh, H. Thenmozhi, V. Jeyachandran, R. R. Kumar and P. L. N. Lakshman

Abstract top

In the title compound, C25H25ClO2, the C ring adopts a chair conformation, while the B ring approximates a half-chair conformation. The five-membered ring D has a twist conformation on the C-C bond fused with the C ring. Aromatic rings A and E are not coplanar, as evidenced by the dihedral angle of 7.51 (1)°. In the crystal, O-H...O hydrogen bonds form a double chain along the ab plane interconnected by C-H...O interactions.

Comment top

Synthetic steroids have been proposed as radiodiagnostic compounds (Katzenellenbogen, 1995; Silva et al., 2001; Wang et al., 2003), as well as potential drug delivery systems targeting oestrogen receptor positive breast cancer and other diseases associated with the oestrogen receptor ERα. The medicinal importance of the compound in conjunction with our research interests prompted us to synthesize and report the X-ray structure of the title compound.

In the title compound (Fig. 1), ring C, with trans fusion to rings B and D, is fixed in a chair conformation, and the ring D adopts a slightly twisted envelope conformation, as characterized by the puckering parameters, q2 = 0.422 (3) Å and φ = 227.8 (2)° (Cremer & Pople, 1975). The steric repulsive hindrance is reduced by a twisting about the C5—C10 bond (Cooper et al., 1969), leading to a slightly deformed half-chair conformation for ring B (Cody et al., 1971), which is supported by the puckering parameters q2 = 0.528 (3) Å, φ = 128.5 (2) ° and θ = 227.8 (2)°. Ring A displays typical characteristic aromaticity, with delocalization of π electrons producing an average C≐C bond length of 1.381 (3) Å (Duax et al., 1976). Additionally, the C4≐C5≐C6 bond angle is reduced to a value of 117.27 (16)°. These facts are due to a strong interaction of the aromatic atom H4 of ring A and equatorial atom H11 atom on ring C, indicated by an interatomic H···H separation of 2.118 (5) Å. The aromatic rings A and E are not coplanar, as evidenced by the dihedral angle of 7.51 (1)° between them. All these features are consistent with previously reported structures for similar compounds (Rajnikant et al., 2006; Gunasekaran et al., 2009).

The crystal structure features intermolecular C—H···O and O—H···O interactions in addition to a weak C—H···O intramolecular interaction. The O—H···O interactions form a double chain interconnected by the C—H···O interactions (Fig. 2).

Related literature top

For applications of steroids as radiodiagnostic compounds and drug delivery systems, see: Katzenellenbogen (1995); Silva et al. (2001); Wang et al. (2003). For related compounds, see: Cooper et al. (1969); Cody et al. (1971); Rajnikant et al. (2006); Gunasekaran et al. (2009). For conformational analysis of ring systems, see: Cremer & Pople (1975); Duax et al. (1976).

Experimental top

A mixture of oestrone (1 mmol), 4-chloro benzaldehyde (1 mmol), potassium hydroxide (5 ml, 20%) in ethanol (5 ml) was refluxed on an oil bath with stirring at 120 °C for 5 h. After completion of the reaction, as indicated by TLC, the reaction mixture was poured into ice-water (50 ml). The product was filtered and washed with water (100 ml) to obtain the title compound, which was dried under vacuum. The compound was further recrystallized from ethanol to obtain suitable crystals for X-ray analysis. Melting point: 185–186 °C, Yield: 82%.

Refinement top

For the title compound, the absolute configuration expected from the starting reagents was confirmed by the refinement of the Flack parameter (2037 Friedel pairs; Flack, 1983). H atoms were placed at calculated positions and allowed to ride on their carrier atoms with C—H = 0.93–0.98 Å, O—H = 0.82 Å, Uiso(H) =1.2Ueq(carrier C) for CH2 and CH groups, Uiso(H)=1.5Ueq(C14A) for the CH3 group, and Uiso(H1)=1.5Ueq(O1).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 40% probability displacement ellipsoids.
[Figure 2] Fig. 2. Partial packing diagram showing double chains formation.
(E)-16-(4-Chlorobenzylidene)estrone top
Crystal data top
C25H25ClO2Dx = 1.294 Mg m−3
Mr = 392.90Melting point: 458 K
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 2000 reflections
a = 6.3601 (3) Åθ = 2–31°
b = 11.2012 (6) ŵ = 0.21 mm−1
c = 28.3043 (14) ÅT = 293 K
V = 2016.42 (18) Å3Block, colourless
Z = 40.17 × 0.15 × 0.13 mm
F(000) = 832
Data collection top
Bruker Kappa APEXII
diffractometer		4819 independent reflections
Radiation source: fine-focus sealed tube3788 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
Detector resolution: 0 pixels mm-1θmax = 27.9°, θmin = 2.3°
ω and φ scansh = −8→7
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		k = −14→14
Tmin = 0.967, Tmax = 0.974l = −37→36
23011 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.043H-atom parameters constrained
wR(F2) = 0.100 w = 1/[σ2(Fo2) + (0.0435P)2 + 0.2966P]
where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max = 0.001
4819 reflectionsΔρmax = 0.22 e Å−3
253 parametersΔρmin = −0.26 e Å−3
0 restraintsAbsolute structure: Flack (1983), 2037 Friedel pairs
0 constraintsFlack parameter: 0.06 (7)
Primary atom site location: structure-invariant direct methods
Crystal data top
C25H25ClO2V = 2016.42 (18) Å3
Mr = 392.90Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 6.3601 (3) ŵ = 0.21 mm−1
b = 11.2012 (6) ÅT = 293 K
c = 28.3043 (14) Å0.17 × 0.15 × 0.13 mm
Data collection top
Bruker Kappa APEXII
diffractometer		4819 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		3788 reflections with I > 2σ(I)
Tmin = 0.967, Tmax = 0.974Rint = 0.034
23011 measured reflectionsθmax = 27.9°
Refinement top
R[F2 > 2σ(F2)] = 0.043H-atom parameters constrained
wR(F2) = 0.100Δρmax = 0.22 e Å−3
S = 1.02Δρmin = −0.26 e Å−3
4819 reflectionsAbsolute structure: Flack (1983), 2037 Friedel pairs
253 parametersFlack parameter: 0.06 (7)
0 restraints
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.2517 (3)−0.05590 (16)0.09206 (6)0.0420 (4)
H1A0.1200−0.07540.10410.050*
C20.3552 (3)−0.13702 (16)0.06397 (7)0.0448 (4)
C30.5521 (3)−0.10893 (17)0.04649 (7)0.0478 (5)
H30.6251−0.16340.02790.057*
C40.6387 (3)0.00039 (17)0.05695 (7)0.0451 (4)
H40.77130.01840.04510.054*
C50.5365 (3)0.08533 (15)0.08452 (6)0.0369 (4)
C60.3391 (3)0.05456 (16)0.10293 (6)0.0367 (4)
C70.2169 (3)0.13852 (16)0.13436 (7)0.0452 (5)
H7A0.16930.09490.16200.054*
H7B0.09320.16570.11740.054*
C80.3413 (3)0.24637 (17)0.15048 (7)0.0456 (5)
H8A0.43550.22340.17590.055*
H8B0.24590.30670.16250.055*
C90.4680 (3)0.29775 (15)0.10975 (6)0.0358 (4)
H90.37310.31140.08300.043*
C100.6358 (3)0.20596 (16)0.09476 (6)0.0367 (4)
H100.72750.19440.12220.044*
C110.7758 (3)0.25270 (16)0.05509 (7)0.0461 (5)
H11A0.69300.25890.02640.055*
H11B0.88730.19540.04930.055*
C120.8747 (3)0.37515 (17)0.06580 (7)0.0486 (5)
H12A0.97540.36730.09140.058*
H12B0.94890.40400.03810.058*
C130.7053 (3)0.46360 (16)0.07958 (6)0.0394 (4)
C14A0.5673 (3)0.49699 (18)0.03654 (7)0.0533 (5)
H14A0.46140.55310.04610.080*
H14B0.50120.42640.02430.080*
H14C0.65370.53220.01250.080*
C150.5779 (3)0.41378 (15)0.12129 (6)0.0362 (4)
H150.68050.39490.14600.043*
C160.4532 (3)0.52206 (15)0.13940 (7)0.0420 (4)
H16A0.32780.53550.12060.050*
H16B0.41350.51220.17230.050*
C170.6101 (3)0.62256 (17)0.13336 (7)0.0433 (4)
C180.7770 (3)0.58149 (17)0.10050 (7)0.0449 (4)
C190.6214 (3)0.73160 (17)0.15245 (7)0.0464 (5)
H190.74010.77540.14420.056*
C200.4751 (3)0.79255 (16)0.18433 (7)0.0459 (4)
C210.2732 (4)0.75169 (18)0.19375 (8)0.0574 (6)
H210.22740.68110.17980.069*
C220.1395 (4)0.8131 (2)0.22317 (8)0.0610 (6)
H220.00650.78310.22990.073*
C230.2042 (4)0.91873 (19)0.24246 (7)0.0544 (5)
C240.4006 (4)0.9632 (2)0.23352 (8)0.0598 (6)
H240.44341.03500.24690.072*
C250.5342 (4)0.90013 (18)0.20449 (7)0.0538 (5)
H250.66740.93050.19830.065*
O10.2750 (2)−0.24606 (12)0.05227 (6)0.0622 (4)
H10.1584−0.25380.06420.093*
O20.9391 (2)0.63375 (13)0.09181 (6)0.0698 (5)
Cl10.03190 (11)0.99936 (6)0.27780 (3)0.0845 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0336 (9)0.0398 (10)0.0525 (11)−0.0008 (8)0.0016 (8)0.0097 (9)
C20.0501 (11)0.0320 (10)0.0524 (11)−0.0018 (8)−0.0056 (9)0.0039 (8)
C30.0495 (11)0.0361 (10)0.0577 (11)0.0013 (9)0.0092 (10)−0.0032 (9)
C40.0377 (9)0.0409 (11)0.0568 (11)0.0017 (8)0.0105 (9)−0.0006 (9)
C50.0341 (8)0.0333 (9)0.0431 (9)0.0020 (8)0.0006 (7)0.0032 (7)
C60.0339 (8)0.0325 (9)0.0438 (9)0.0038 (7)0.0002 (7)0.0062 (8)
C70.0378 (9)0.0400 (10)0.0580 (11)−0.0005 (8)0.0134 (9)0.0061 (9)
C80.0465 (10)0.0391 (11)0.0512 (11)0.0010 (9)0.0156 (9)−0.0010 (9)
C90.0342 (8)0.0346 (9)0.0386 (9)0.0004 (7)0.0058 (7)0.0005 (7)
C100.0312 (8)0.0350 (9)0.0439 (10)0.0017 (7)0.0010 (8)0.0002 (8)
C110.0417 (10)0.0403 (10)0.0564 (11)−0.0024 (9)0.0148 (9)−0.0033 (9)
C120.0417 (10)0.0448 (11)0.0592 (12)−0.0069 (9)0.0138 (9)−0.0033 (9)
C130.0384 (9)0.0354 (10)0.0445 (10)−0.0052 (8)0.0049 (8)0.0023 (8)
C14A0.0700 (13)0.0475 (12)0.0425 (10)−0.0061 (11)−0.0005 (9)0.0057 (9)
C150.0350 (8)0.0336 (9)0.0399 (9)−0.0022 (7)0.0014 (7)0.0010 (7)
C160.0439 (9)0.0369 (10)0.0452 (10)−0.0026 (8)0.0046 (8)−0.0027 (8)
C170.0461 (10)0.0369 (10)0.0469 (10)−0.0015 (8)−0.0024 (8)0.0003 (8)
C180.0425 (10)0.0384 (10)0.0538 (11)−0.0061 (9)0.0019 (9)0.0023 (9)
C190.0480 (11)0.0397 (11)0.0515 (11)−0.0076 (9)−0.0042 (9)0.0014 (9)
C200.0550 (12)0.0349 (10)0.0478 (10)0.0000 (9)−0.0085 (9)−0.0002 (8)
C210.0620 (13)0.0367 (11)0.0733 (14)−0.0061 (10)0.0060 (11)−0.0110 (10)
C220.0599 (13)0.0450 (12)0.0783 (15)0.0008 (10)0.0035 (12)−0.0082 (11)
C230.0647 (13)0.0475 (12)0.0509 (12)0.0134 (11)−0.0067 (10)−0.0081 (10)
C240.0730 (15)0.0440 (12)0.0625 (13)0.0030 (11)−0.0198 (11)−0.0163 (10)
C250.0563 (12)0.0451 (11)0.0601 (12)−0.0018 (10)−0.0122 (10)−0.0041 (10)
O10.0611 (9)0.0404 (8)0.0852 (10)−0.0128 (7)0.0066 (8)−0.0107 (7)
O20.0550 (9)0.0561 (9)0.0982 (12)−0.0228 (8)0.0191 (9)−0.0089 (9)
Cl10.0868 (4)0.0770 (5)0.0897 (4)0.0234 (4)−0.0009 (4)−0.0325 (3)
Geometric parameters (Å, º) top
C1—C21.375 (3)C13—C181.517 (3)
C1—C61.391 (3)C13—C151.537 (2)
C1—H1A0.9300C13—C14A1.547 (3)
C2—O11.364 (2)C14A—H14A0.9600
C2—C31.382 (3)C14A—H14B0.9600
C3—C41.375 (3)C14A—H14C0.9600
C3—H30.9300C15—C161.537 (2)
C4—C51.391 (2)C15—H150.9800
C4—H40.9300C16—C171.514 (3)
C5—C61.403 (2)C16—H16A0.9700
C5—C101.519 (3)C16—H16B0.9700
C6—C71.510 (3)C17—C191.337 (3)
C7—C81.515 (3)C17—C181.484 (3)
C7—H7A0.9700C18—O21.211 (2)
C7—H7B0.9700C19—C201.465 (3)
C8—C91.520 (2)C19—H190.9300
C8—H8A0.9700C20—C251.385 (3)
C8—H8B0.9700C20—C211.389 (3)
C9—C151.511 (2)C21—C221.375 (3)
C9—C101.542 (2)C21—H210.9300
C9—H90.9800C22—C231.367 (3)
C10—C111.526 (2)C22—H220.9300
C10—H100.9800C23—C241.368 (3)
C11—C121.539 (3)C23—Cl11.737 (2)
C11—H11A0.9700C24—C251.376 (3)
C11—H11B0.9700C24—H240.9300
C12—C131.515 (3)C25—H250.9300
C12—H12A0.9700O1—H10.8200
C12—H12B0.9700
C2—C1—C6121.61 (16)H12A—C12—H12B108.2
C2—C1—H1A119.2C12—C13—C18117.13 (15)
C6—C1—H1A119.2C12—C13—C15109.59 (14)
O1—C2—C1123.56 (18)C18—C13—C15100.06 (14)
O1—C2—C3117.09 (18)C12—C13—C14A111.03 (16)
C1—C2—C3119.35 (17)C18—C13—C14A105.50 (15)
C4—C3—C2119.25 (18)C15—C13—C14A113.17 (15)
C4—C3—H3120.4C13—C14A—H14A109.5
C2—C3—H3120.4C13—C14A—H14B109.5
C3—C4—C5122.86 (17)H14A—C14A—H14B109.5
C3—C4—H4118.6C13—C14A—H14C109.5
C5—C4—H4118.6H14A—C14A—H14C109.5
C4—C5—C6117.27 (16)H14B—C14A—H14C109.5
C4—C5—C10121.40 (16)C9—C15—C13112.96 (14)
C6—C5—C10121.32 (16)C9—C15—C16120.79 (14)
C1—C6—C5119.63 (16)C13—C15—C16103.99 (13)
C1—C6—C7118.60 (16)C9—C15—H15106.0
C5—C6—C7121.77 (16)C13—C15—H15106.0
C6—C7—C8113.92 (15)C16—C15—H15106.0
C6—C7—H7A108.8C17—C16—C15102.05 (14)
C8—C7—H7A108.8C17—C16—H16A111.4
C6—C7—H7B108.8C15—C16—H16A111.4
C8—C7—H7B108.8C17—C16—H16B111.4
H7A—C7—H7B107.7C15—C16—H16B111.4
C7—C8—C9110.52 (15)H16A—C16—H16B109.2
C7—C8—H8A109.5C19—C17—C18119.86 (18)
C9—C8—H8A109.5C19—C17—C16131.97 (18)
C7—C8—H8B109.5C18—C17—C16108.15 (15)
C9—C8—H8B109.5O2—C18—C17125.89 (18)
H8A—C8—H8B108.1O2—C18—C13126.68 (18)
C15—C9—C8114.01 (14)C17—C18—C13107.43 (15)
C15—C9—C10108.23 (14)C17—C19—C20129.83 (18)
C8—C9—C10108.86 (14)C17—C19—H19115.1
C15—C9—H9108.5C20—C19—H19115.1
C8—C9—H9108.5C25—C20—C21117.27 (19)
C10—C9—H9108.5C25—C20—C19119.16 (19)
C5—C10—C11114.03 (15)C21—C20—C19123.48 (17)
C5—C10—C9110.97 (14)C22—C21—C20121.56 (19)
C11—C10—C9112.19 (14)C22—C21—H21119.2
C5—C10—H10106.4C20—C21—H21119.2
C11—C10—H10106.4C23—C22—C21119.3 (2)
C9—C10—H10106.4C23—C22—H22120.4
C10—C11—C12113.53 (15)C21—C22—H22120.4
C10—C11—H11A108.9C22—C23—C24121.1 (2)
C12—C11—H11A108.9C22—C23—Cl1119.36 (18)
C10—C11—H11B108.9C24—C23—Cl1119.57 (17)
C12—C11—H11B108.9C23—C24—C25119.16 (19)
H11A—C11—H11B107.7C23—C24—H24120.4
C13—C12—C11110.05 (15)C25—C24—H24120.4
C13—C12—H12A109.7C24—C25—C20121.7 (2)
C11—C12—H12A109.7C24—C25—H25119.2
C13—C12—H12B109.7C20—C25—H25119.2
C11—C12—H12B109.7C2—O1—H1109.5
C6—C1—C2—O1−179.72 (17)C10—C9—C15—C16−177.53 (15)
C6—C1—C2—C30.8 (3)C12—C13—C15—C9−61.04 (19)
O1—C2—C3—C4179.40 (17)C18—C13—C15—C9175.26 (14)
C1—C2—C3—C4−1.1 (3)C14A—C13—C15—C963.48 (19)
C2—C3—C4—C5−0.1 (3)C12—C13—C15—C16166.24 (15)
C3—C4—C5—C61.6 (3)C18—C13—C15—C1642.54 (17)
C3—C4—C5—C10−179.11 (17)C14A—C13—C15—C16−69.24 (18)
C2—C1—C6—C50.7 (3)C9—C15—C16—C17−165.37 (15)
C2—C1—C6—C7−179.44 (17)C13—C15—C16—C17−37.32 (17)
C4—C5—C6—C1−1.8 (2)C15—C16—C17—C19−161.1 (2)
C10—C5—C6—C1178.84 (16)C15—C16—C17—C1817.24 (19)
C4—C5—C6—C7178.34 (17)C19—C17—C18—O27.3 (3)
C10—C5—C6—C7−1.0 (3)C16—C17—C18—O2−171.3 (2)
C1—C6—C7—C8170.23 (16)C19—C17—C18—C13−172.01 (17)
C5—C6—C7—C8−9.9 (2)C16—C17—C18—C139.4 (2)
C6—C7—C8—C943.0 (2)C12—C13—C18—O230.6 (3)
C7—C8—C9—C15173.49 (15)C15—C13—C18—O2148.9 (2)
C7—C8—C9—C10−65.58 (19)C14A—C13—C18—O2−93.5 (2)
C4—C5—C10—C1131.8 (2)C12—C13—C18—C17−150.10 (16)
C6—C5—C10—C11−148.94 (16)C15—C13—C18—C17−31.83 (18)
C4—C5—C10—C9159.62 (16)C14A—C13—C18—C1785.80 (17)
C6—C5—C10—C9−21.1 (2)C18—C17—C19—C20178.14 (18)
C15—C9—C10—C5177.72 (14)C16—C17—C19—C20−3.7 (4)
C8—C9—C10—C553.30 (19)C17—C19—C20—C25171.5 (2)
C15—C9—C10—C11−53.43 (19)C17—C19—C20—C21−12.1 (3)
C8—C9—C10—C11−177.85 (15)C25—C20—C21—C22−2.2 (3)
C5—C10—C11—C12179.77 (15)C19—C20—C21—C22−178.62 (19)
C9—C10—C11—C1252.5 (2)C20—C21—C22—C232.1 (3)
C10—C11—C12—C13−53.1 (2)C21—C22—C23—C24−1.0 (3)
C11—C12—C13—C18168.38 (16)C21—C22—C23—Cl1177.52 (17)
C11—C12—C13—C1555.4 (2)C22—C23—C24—C250.2 (3)
C11—C12—C13—C14A−70.4 (2)Cl1—C23—C24—C25−178.34 (16)
C8—C9—C15—C13179.84 (15)C23—C24—C25—C20−0.4 (3)
C10—C9—C15—C1358.55 (18)C21—C20—C25—C241.4 (3)
C8—C9—C15—C16−56.2 (2)C19—C20—C25—C24177.93 (19)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O2i0.822.032.762 (3)148
C14A—H14A···O1ii0.962.553.454 (3)157
Symmetry codes: (i) x−1, y−1, z; (ii) x, y+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1···O2i0.822.032.762 (3)148
C14A—H14A···O1ii0.962.553.454 (3)157
Symmetry codes: (i) x−1, y−1, z; (ii) x, y+1, z.
Acknowledgements top

JS thanks the UGC for the FIST support. JS and HT thank the management of Madura College for their encouragement and support. RRK thanks the DST, New Delhi for funds under the fast-track scheme (No. SR/FT/CS-073/2009)

references
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