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Acta Cryst. (2012). E68, o2638    [ doi:10.1107/S1600536812033934 ]

2,2'-[(4-Ethoxyphenyl)methylene]bis(3-hydroxy-5,5-dimethylcyclohex-2-en-1-one)

N. Sureshbabu and V. Sughanya

Abstract top

In the title compound, C25H32O5, the two cyclohexenone rings have envelope conformations with the C atom bearing two methyl groups as the flap atom in each ring. Relatively strong intramolecular O-H...O hydrogen bonds are observed.

Comment top

Several methods have been reported in the literature (Vang & Stankevich, 1960; Hilderbrand & Weissleder, 2007) for the synthesis of the title compound. Xanthene derivatives possess biological properties such as antibacterial, antiviral and anti-inflammatory activities (Jonathan et al., 1988) and are therefore used in medicine.

In the title compound, the cyclohexenone rings C10–C15 and C18–C23 both adopt envelope conformations, with flap atoms C13 and C21, respectively.The dihedral angle between the two cyclohexenone planes Q(C10/C11/C12/C14/C15) and R(C18/C19/C20/C22/C23) is 58.42 (3)°. The dihedral angle between the benzene ring P(C3–C8) and cyclohexenone planes Q and R are 66.37 (3)° and 61.41 (4)°, respectively.. The hydroxy and carbonyl oxygen atoms face each other and are oriented to allow for the formation of two intramolecular O—H···O hydrogen bonds (Table 1, Fig. 2), typical for xanthene derivatives.

Related literature top

For the synthesis of bisdimedones, see: Vang & Stankevich (1960); Hilderbrand & Weissleder (2007). For their pharmaceutical properties, see: Lambert et al. (1997); Poupelin et al. (1978); Hideo (1981); Selvanayagam et al. (1996); Jonathan et al. (1988). For the crystal structures of related xanthene derivatives, see: Odabaşoğlu et al. (2008); Mehdi et al. (2011); Ravikumar et al. (2012). For the assignment of ring conformations, see: Cremer & Pople (1975).

Experimental top

The title compound was prepared in a single stage. A mixture of 4-Ethoxybenzaldehyde (1.2g, 8 mmol), 5,5-dimethylcyclohexane-1,3-dione (2.24g, 16 mmol) and 20ml of ethanol was heated to 70 °C for about 10 minutes. The reaction mixture was allowed to cool to room temperature and the resulting title compound, 2,2'-((4-ethoxyphenyl)methylene) bis(3-hydroxy-5,5-dimethylcyclohex-2-enone) was filtered and dried (M.p. 411 K; Yield 78% ).

Refinement top

All hydrogen atoms were identified from difference electron density peaks and subsequently treated as riding atoms with d(Csp2—H) = 0.93 Å, d(Cmethyl—H) = 0.96 Å, d(Cmethylene—H) = 0.97 Å, d(Cmethine—H) = 0.98 Å; d(O—H) = 0.82 Å; Uiso(H) = xUeq(C,O), where x = 1.5 for methyl H and 1.2 for all other H atoms.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A view of the structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level. Hydrogen atoms are shown as spheres of arbitrary radius.
[Figure 2] Fig. 2. A view of the packing in the crystal structure, showing intramolecular O—H···O hydrogen bonds as dotted lines.
2,2'-[(4-Ethoxyphenyl)methylene]bis(3-hydroxy-5,5-dimethylcyclohex-2-en-1-one) top
Crystal data top
C25H32O5F(000) = 888
Mr = 412.51Dx = 1.217 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
a = 9.774 (5) ÅCell parameters from 6149 reflections
b = 10.698 (5) Åθ = 2.1–27.1°
c = 21.578 (5) ŵ = 0.08 mm−1
β = 93.735 (5)°T = 293 K
V = 2251.5 (16) Å3Block, colourless
Z = 40.30 × 0.20 × 0.20 mm
Data collection top
Bruker Kappa APEXII CCD
diffractometer		3962 independent reflections
Radiation source: fine-focus sealed tube3065 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.028
ω and φ scanθmax = 25.0°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		h = −11→7
Tmin = 0.961, Tmax = 0.989k = −12→12
17055 measured reflectionsl = −24→25
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)] = 0.042H-atom parameters constrained
wR(F2) = 0.122 w = 1/[σ2(Fo2) + (0.0573P)2 + 0.7618P]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max < 0.001
3962 reflectionsΔρmax = 0.24 e Å−3
272 parametersΔρmin = −0.23 e Å−3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0143 (14)
Crystal data top
C25H32O5V = 2251.5 (16) Å3
Mr = 412.51Z = 4
Monoclinic, P21/nMo Kα radiation
a = 9.774 (5) ŵ = 0.08 mm−1
b = 10.698 (5) ÅT = 293 K
c = 21.578 (5) Å0.30 × 0.20 × 0.20 mm
β = 93.735 (5)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer		3962 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)		3065 reflections with I > 2σ(I)
Tmin = 0.961, Tmax = 0.989Rint = 0.028
17055 measured reflectionsθmax = 25.0°
Refinement top
R[F2 > 2σ(F2)] = 0.042H-atom parameters constrained
wR(F2) = 0.122Δρmax = 0.24 e Å−3
S = 1.03Δρmin = −0.23 e Å−3
3962 reflectionsAbsolute structure: ?
272 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
C10.1136 (3)0.5154 (3)0.33826 (11)0.0776 (7)
H1A0.15500.52260.29930.116*
H1B0.08360.59640.35100.116*
H1C0.03630.46000.33370.116*
C20.2151 (2)0.4651 (3)0.38572 (10)0.0707 (7)
H2A0.24570.38310.37320.085*
H2B0.29430.51980.39000.085*
C30.22806 (19)0.40529 (19)0.49280 (8)0.0495 (5)
C40.3642 (2)0.3757 (2)0.49343 (9)0.0567 (6)
H40.41290.39110.45860.068*
C50.42951 (19)0.32300 (19)0.54571 (9)0.0518 (5)
H50.52210.30320.54520.062*
C60.36275 (17)0.29861 (16)0.59866 (7)0.0368 (4)
C70.22621 (18)0.33226 (18)0.59738 (8)0.0474 (5)
H70.17810.31910.63260.057*
C80.15904 (19)0.3846 (2)0.54565 (9)0.0547 (5)
H80.06690.40610.54630.066*
C90.44542 (16)0.24953 (15)0.65658 (7)0.0350 (4)
H90.49800.32240.67200.042*
C100.55496 (16)0.15470 (16)0.64172 (7)0.0359 (4)
C110.52716 (17)0.05495 (16)0.60035 (7)0.0373 (4)
C120.63981 (18)−0.02547 (18)0.57850 (8)0.0474 (5)
H12A0.6192−0.04510.53500.057*
H12B0.6408−0.10350.60140.057*
C130.78274 (18)0.0323 (2)0.58573 (8)0.0497 (5)
C140.80122 (19)0.0814 (2)0.65212 (9)0.0564 (5)
H14A0.81010.01080.68030.068*
H14B0.88580.12880.65660.068*
C150.68583 (18)0.16245 (18)0.67054 (8)0.0433 (4)
C160.7976 (2)0.1388 (2)0.53921 (10)0.0651 (6)
H16A0.88830.17330.54460.098*
H16B0.73140.20270.54620.098*
H16C0.78250.10710.49770.098*
C170.8898 (2)−0.0678 (2)0.57416 (11)0.0714 (7)
H17A0.8820−0.13490.60330.107*
H17B0.9798−0.03190.57930.107*
H17C0.8746−0.09940.53260.107*
C180.36132 (16)0.21294 (15)0.71075 (7)0.0341 (4)
C190.25324 (17)0.12859 (16)0.70621 (8)0.0373 (4)
C200.1721 (2)0.09839 (17)0.76079 (9)0.0472 (5)
H20A0.21150.02510.78150.057*
H20B0.07900.07770.74590.057*
C210.16771 (18)0.20449 (17)0.80774 (8)0.0434 (4)
C220.31497 (19)0.24452 (19)0.82458 (8)0.0457 (5)
H22A0.31350.32330.84680.055*
H22B0.35760.18290.85260.055*
C230.40218 (18)0.25987 (16)0.77023 (8)0.0394 (4)
C240.08261 (19)0.31254 (19)0.78021 (9)0.0516 (5)
H24A0.08110.37910.81000.077*
H24B−0.00930.28450.76980.077*
H24C0.12240.34220.74340.077*
C250.1019 (2)0.1593 (2)0.86609 (10)0.0667 (6)
H25A0.10000.22660.89540.100*
H25B0.15430.09120.88420.100*
H25C0.00990.13180.85520.100*
O10.15317 (15)0.45642 (16)0.44304 (6)0.0703 (5)
O20.40539 (12)0.02575 (12)0.58061 (5)0.0467 (3)
O30.71819 (13)0.23817 (14)0.71624 (6)0.0597 (4)
H3A0.64810.26630.72990.072*
O40.21555 (12)0.06855 (12)0.65595 (6)0.0477 (3)
H4A0.27930.06630.63310.057*
O50.51622 (13)0.31629 (13)0.78119 (6)0.0527 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0780 (16)0.0951 (18)0.0589 (14)−0.0061 (14)−0.0029 (12)0.0242 (13)
C20.0646 (14)0.0954 (18)0.0529 (13)0.0138 (12)0.0107 (11)0.0272 (13)
C30.0478 (11)0.0603 (12)0.0411 (10)0.0145 (9)0.0076 (8)0.0138 (9)
C40.0508 (12)0.0773 (14)0.0440 (11)0.0176 (10)0.0187 (9)0.0229 (10)
C50.0379 (10)0.0693 (13)0.0497 (11)0.0141 (9)0.0138 (8)0.0178 (10)
C60.0370 (9)0.0376 (9)0.0365 (9)0.0018 (7)0.0066 (7)0.0024 (7)
C70.0406 (10)0.0626 (12)0.0405 (10)0.0109 (9)0.0132 (8)0.0102 (9)
C80.0390 (10)0.0751 (14)0.0510 (11)0.0181 (9)0.0117 (8)0.0158 (10)
C90.0330 (8)0.0373 (9)0.0349 (9)−0.0032 (7)0.0035 (7)−0.0011 (7)
C100.0345 (9)0.0440 (10)0.0294 (8)0.0006 (7)0.0034 (7)0.0028 (7)
C110.0385 (9)0.0458 (10)0.0278 (8)0.0013 (7)0.0036 (7)0.0048 (7)
C120.0498 (11)0.0536 (11)0.0393 (10)0.0099 (9)0.0070 (8)−0.0028 (9)
C130.0400 (10)0.0690 (13)0.0404 (10)0.0151 (9)0.0056 (8)0.0012 (9)
C140.0379 (10)0.0842 (15)0.0464 (11)0.0132 (10)−0.0034 (8)−0.0067 (11)
C150.0369 (9)0.0597 (11)0.0334 (9)−0.0015 (8)0.0019 (7)−0.0024 (9)
C160.0528 (13)0.0821 (16)0.0623 (13)0.0027 (11)0.0171 (10)0.0066 (12)
C170.0564 (13)0.0975 (18)0.0607 (13)0.0304 (12)0.0077 (10)−0.0055 (13)
C180.0346 (9)0.0354 (9)0.0325 (9)0.0014 (7)0.0043 (7)−0.0005 (7)
C190.0379 (9)0.0359 (9)0.0384 (9)0.0019 (7)0.0056 (7)−0.0020 (8)
C200.0492 (11)0.0432 (10)0.0509 (11)−0.0054 (8)0.0168 (8)0.0013 (9)
C210.0460 (10)0.0459 (10)0.0397 (10)0.0004 (8)0.0142 (8)0.0002 (8)
C220.0494 (11)0.0536 (11)0.0347 (10)0.0085 (9)0.0067 (8)−0.0011 (8)
C230.0386 (9)0.0394 (9)0.0405 (10)0.0030 (8)0.0048 (7)−0.0019 (8)
C240.0437 (11)0.0551 (12)0.0569 (12)0.0061 (9)0.0096 (9)−0.0031 (10)
C250.0746 (15)0.0732 (15)0.0559 (13)−0.0010 (12)0.0305 (11)0.0050 (11)
O10.0564 (9)0.1055 (13)0.0500 (8)0.0307 (8)0.0115 (7)0.0312 (8)
O20.0411 (7)0.0590 (8)0.0398 (7)−0.0045 (6)0.0008 (5)−0.0075 (6)
O30.0373 (7)0.0860 (10)0.0556 (8)−0.0051 (7)0.0016 (6)−0.0234 (8)
O40.0441 (7)0.0527 (8)0.0472 (7)−0.0104 (6)0.0099 (6)−0.0117 (6)
O50.0459 (8)0.0660 (9)0.0460 (7)−0.0096 (6)0.0029 (6)−0.0164 (7)
Geometric parameters (Å, º) top
C1—C21.481 (3)C14—C151.497 (3)
C1—H1A0.9600C14—H14A0.9700
C1—H1B0.9600C14—H14B0.9700
C1—H1C0.9600C15—O31.299 (2)
C2—O11.415 (2)C16—H16A0.9600
C2—H2A0.9700C16—H16B0.9600
C2—H2B0.9700C16—H16C0.9600
C3—C41.367 (3)C17—H17A0.9600
C3—O11.373 (2)C17—H17B0.9600
C3—C81.380 (3)C17—H17C0.9600
C4—C51.380 (3)C18—C191.388 (2)
C4—H40.9300C18—C231.411 (2)
C5—C61.377 (2)C19—O41.293 (2)
C5—H50.9300C19—C201.497 (2)
C6—C71.381 (2)C20—C211.524 (3)
C6—C91.536 (2)C20—H20A0.9700
C7—C81.377 (3)C20—H20B0.9700
C7—H70.9300C21—C241.522 (3)
C8—H80.9300C21—C221.523 (3)
C9—C181.523 (2)C21—C251.529 (3)
C9—C101.524 (2)C22—C231.503 (2)
C9—H90.9800C22—H22A0.9700
C10—C151.388 (2)C22—H22B0.9700
C10—C111.406 (2)C23—O51.276 (2)
C11—O21.276 (2)C24—H24A0.9600
C11—C121.497 (2)C24—H24B0.9600
C12—C131.526 (3)C24—H24C0.9600
C12—H12A0.9700C25—H25A0.9600
C12—H12B0.9700C25—H25B0.9600
C13—C141.525 (3)C25—H25C0.9600
C13—C171.529 (3)O3—H3A0.8200
C13—C161.531 (3)O4—H4A0.8200
C2—C1—H1A109.5H14A—C14—H14B107.7
C2—C1—H1B109.5O3—C15—C10123.30 (17)
H1A—C1—H1B109.5O3—C15—C14114.36 (15)
C2—C1—H1C109.5C10—C15—C14122.33 (16)
H1A—C1—H1C109.5C13—C16—H16A109.5
H1B—C1—H1C109.5C13—C16—H16B109.5
O1—C2—C1108.82 (19)H16A—C16—H16B109.5
O1—C2—H2A109.9C13—C16—H16C109.5
C1—C2—H2A109.9H16A—C16—H16C109.5
O1—C2—H2B109.9H16B—C16—H16C109.5
C1—C2—H2B109.9C13—C17—H17A109.5
H2A—C2—H2B108.3C13—C17—H17B109.5
C4—C3—O1124.68 (16)H17A—C17—H17B109.5
C4—C3—C8118.85 (17)C13—C17—H17C109.5
O1—C3—C8116.46 (16)H17A—C17—H17C109.5
C3—C4—C5120.04 (17)H17B—C17—H17C109.5
C3—C4—H4120.0C19—C18—C23117.68 (15)
C5—C4—H4120.0C19—C18—C9124.00 (15)
C6—C5—C4122.47 (17)C23—C18—C9118.13 (14)
C6—C5—H5118.8O4—C19—C18123.79 (15)
C4—C5—H5118.8O4—C19—C20114.57 (15)
C5—C6—C7116.33 (16)C18—C19—C20121.63 (15)
C5—C6—C9119.16 (15)C19—C20—C21113.67 (15)
C7—C6—C9124.19 (15)C19—C20—H20A108.8
C8—C7—C6122.12 (16)C21—C20—H20A108.8
C8—C7—H7118.9C19—C20—H20B108.8
C6—C7—H7118.9C21—C20—H20B108.8
C7—C8—C3120.15 (17)H20A—C20—H20B107.7
C7—C8—H8119.9C24—C21—C22111.33 (16)
C3—C8—H8119.9C24—C21—C20110.15 (16)
C18—C9—C10114.33 (14)C22—C21—C20107.52 (15)
C18—C9—C6115.51 (13)C24—C21—C25108.22 (16)
C10—C9—C6113.32 (13)C22—C21—C25109.52 (16)
C18—C9—H9103.9C20—C21—C25110.09 (16)
C10—C9—H9103.9C23—C22—C21114.81 (14)
C6—C9—H9103.9C23—C22—H22A108.6
C15—C10—C11117.65 (16)C21—C22—H22A108.6
C15—C10—C9120.37 (15)C23—C22—H22B108.6
C11—C10—C9121.95 (14)C21—C22—H22B108.6
O2—C11—C10122.34 (15)H22A—C22—H22B107.5
O2—C11—C12116.30 (16)O5—C23—C18121.93 (16)
C10—C11—C12121.34 (15)O5—C23—C22116.10 (15)
C11—C12—C13114.95 (16)C18—C23—C22121.96 (16)
C11—C12—H12A108.5C21—C24—H24A109.5
C13—C12—H12A108.5C21—C24—H24B109.5
C11—C12—H12B108.5H24A—C24—H24B109.5
C13—C12—H12B108.5C21—C24—H24C109.5
H12A—C12—H12B107.5H24A—C24—H24C109.5
C14—C13—C12106.67 (15)H24B—C24—H24C109.5
C14—C13—C17110.72 (16)C21—C25—H25A109.5
C12—C13—C17109.32 (18)C21—C25—H25B109.5
C14—C13—C16110.46 (19)H25A—C25—H25B109.5
C12—C13—C16111.08 (16)C21—C25—H25C109.5
C17—C13—C16108.59 (17)H25A—C25—H25C109.5
C15—C14—C13113.79 (15)H25B—C25—H25C109.5
C15—C14—H14A108.8C3—O1—C2118.21 (15)
C13—C14—H14A108.8C15—O3—H3A109.5
C15—C14—H14B108.8C19—O4—H4A109.5
C13—C14—H14B108.8
O1—C3—C4—C5−179.1 (2)C9—C10—C15—O38.8 (3)
C8—C3—C4—C51.7 (3)C11—C10—C15—C149.3 (3)
C3—C4—C5—C6−0.3 (3)C9—C10—C15—C14−172.57 (17)
C4—C5—C6—C7−1.3 (3)C13—C14—C15—O3−157.30 (18)
C4—C5—C6—C9−175.17 (19)C13—C14—C15—C1024.0 (3)
C5—C6—C7—C81.5 (3)C10—C9—C18—C19−79.6 (2)
C9—C6—C7—C8175.01 (18)C6—C9—C18—C1954.6 (2)
C6—C7—C8—C3−0.1 (3)C10—C9—C18—C2395.19 (18)
C4—C3—C8—C7−1.6 (3)C6—C9—C18—C23−130.60 (16)
O1—C3—C8—C7179.2 (2)C23—C18—C19—O4−172.22 (15)
C5—C6—C9—C18−174.17 (16)C9—C18—C19—O42.6 (3)
C7—C6—C9—C1812.5 (2)C23—C18—C19—C206.6 (2)
C5—C6—C9—C10−39.5 (2)C9—C18—C19—C20−178.58 (15)
C7—C6—C9—C10147.15 (18)O4—C19—C20—C21−152.94 (16)
C18—C9—C10—C15−89.34 (19)C18—C19—C20—C2128.2 (2)
C6—C9—C10—C15135.45 (16)C19—C20—C21—C2469.2 (2)
C18—C9—C10—C1188.71 (18)C19—C20—C21—C22−52.3 (2)
C6—C9—C10—C11−46.5 (2)C19—C20—C21—C25−171.51 (17)
C15—C10—C11—O2166.58 (16)C24—C21—C22—C23−75.1 (2)
C9—C10—C11—O2−11.5 (2)C20—C21—C22—C2345.6 (2)
C15—C10—C11—C12−11.6 (2)C25—C21—C22—C23165.22 (16)
C9—C10—C11—C12170.32 (15)C19—C18—C23—O5165.19 (16)
O2—C11—C12—C13162.12 (15)C9—C18—C23—O5−10.0 (2)
C10—C11—C12—C13−19.6 (2)C19—C18—C23—C22−13.8 (2)
C11—C12—C13—C1449.0 (2)C9—C18—C23—C22171.03 (15)
C11—C12—C13—C17168.76 (16)C21—C22—C23—O5166.69 (16)
C11—C12—C13—C16−71.4 (2)C21—C22—C23—C18−14.3 (2)
C12—C13—C14—C15−50.8 (2)C4—C3—O1—C28.4 (3)
C17—C13—C14—C15−169.63 (19)C8—C3—O1—C2−172.5 (2)
C16—C13—C14—C1570.0 (2)C1—C2—O1—C3176.6 (2)
C11—C10—C15—O3−169.30 (16)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···O50.821.832.631 (2)164
O4—H4A···O20.821.782.5864 (19)167
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O3—H3A···O50.821.832.631 (2)163.8
O4—H4A···O20.821.782.5864 (19)167.0
Acknowledgements top

The authors thank Dr Babu Varghese and the SAIF, IIT Madras, for the data collection.

references
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