(1RS,6SR)-Ethyl 4-(4-chlorophenyl)-6-(4- fluorophenyl)-2-oxocyclohex-3-ene-1- carboxylate toluene hemisolvate Grzegorz Dutkiewicz, a B. Narayana, b K. Veena, b H. S. Yathirajan c and Maciej Kubicki a * a Department of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60-780 Poznan ´ , Poland, b Department of Studies in Chemistry, Mangalore University, Mangalagangotri 574 199, India, and c Department of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India Correspondence e-mail: [email protected]Received 29 December 2010; accepted 4 January 2011 Key indicators: single-crystal X-ray study; T = 100 K; mean (C–C) = 0.003 A ˚ ; disorder in solvent or counterion; R factor = 0.042; wR factor = 0.085; data-to- parameter ratio = 12.2. In the crystal structure of the title compound, C 21 H 18 ClFO 3 - 0.5C 7 H 8 , the toluene solvent molecules occupy special positions on centres of symmetry, and consequently are disordered across this site. The cyclohexene ring has a slightly distorted sofa conformation; the two benzene rings are inclined by 72.90 (7) and their planes make dihedral angles of 30.09 (10) (chlorophenyl) and 88.13 (6) (fluorophenyl) with the approximately planar part of the cyclohexenone ring [maximum deviation from plane through five atoms is 0.030 (2) A ˚ , the sixth atom is 0.672 (3)A ˚ out of this plane]. Weak intermolecular C—HO and C—HX (X = F, Cl) interactions join molecules into a three-dimensional structure. Also, a relatively short and directional C—ClF—C contact is observed [ClF = 3.119 (2) A ˚ , C—ClF = 157.5 (2) and C—FCl 108.3 (2) ]. The solvent molecules fill the voids in the crystal structure and are kept there by relatively short and directional C—Hinteractions. Related literature For biological applications of some cyclohexanones, see: Eddington et al. (2000). For asymmetry parameters, see: Duax & Norton (1975). For similar structures, see: in Anuradha et al. (2009); Fun et al. (2008, 2009, 2010); Badshah et al. (2009). For a description of the Cambridge Structural Database, see: Allen (2002). Experimental Crystal data C 21 H 18 ClFO 3 0.5C 7 H 8 M r = 418.87 Triclinic, P 1 a = 7.572 (2) A ˚ b = 11.259 (3) A ˚ c = 13.362 (3) A ˚ = 69.42 (2) = 86.58 (2) = 70.98 (2) V = 1006.3 (4) A ˚ 3 Z =2 Mo Kradiation = 0.22 mm 1 T = 100 K 0.3 0.25 0.1 mm Data collection Oxford Diffraction Xcalibur Eos diffractometer Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009) T min = 0.990, T max = 1.000 8414 measured reflections 4154 independent reflections 2567 reflections with I >2(I) R int = 0.030 Refinement R[F 2 >2(F 2 )] = 0.042 wR(F 2 ) = 0.085 S = 1.02 4154 reflections 341 parameters H atoms treated by a mixture of independent and constrained refinement max = 0.24 e A ˚ 3 min = 0.28 e A ˚ 3 Table 1 Hydrogen-bond geometry (A ˚ , ). Cg is the centroid of the C1A–C3A,C1A 0 –C3A 0 ring. D—HA D—H HA DA D—HA C45—H45F64 i 0.94 (2) 2.54 (2) 3.327 (3) 141.6 (15) C5—H52F64 ii 0.938 (19) 2.54 (2) 3.432 (3) 159.3 (15) C6—H6Cl44 iii 1.003 (19) 2.84 (2) 3.846 (3) 176.3 (14) C65—H65O12 iv 0.94 (2) 2.59 (2) 3.519 (3) 173.6 (16) C3—H3Cg 0.918 (19) 2.78 (2) 3.627 (3) 155.0 (17) C3—H3Cg v 0.918 (19) 2.78 (2) 3.627 (3) 155.0 (17) Symmetry codes: (i) x; y; z þ 1; (ii) x þ 1; y; z þ 1; (iii) x þ 1; y; z þ 2; (iv) x þ 2; y; z þ 1; (v) x þ 1; y þ 1; z þ 2. Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR92 (Altomare et al. , 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97. BN thanks the UGC and DST for financial assistance under the SAP and FIST programmes. HSY thanks the UOM for sabbatical leave. organic compounds o334 Dutkiewicz et al. doi:10.1107/S1600536811000158 Acta Cryst. (2011). E67, o334–o335 Acta Crystallographica Section E Structure Reports Online ISSN 1600-5368
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
G. Dutkiewicz, B. Narayana, K. Veena, H. S. Yathirajan and M. Kubicki
Comment
Cyclohexenone derivatives, prepared either from natural sources or entirely via synthetic routes, are known to possess awide variety of biological activities, e.g. they were reported to have anticonvulsant, antimalarial, anti-inflammatory andcardiovascular effects (Eddington et al., 2000). In the course of our studies on chalcone derivatives, we have synthesizedsome cyclohexene derivatives. Structures of some similar compounds have been reported earlier (for instance, ethyl 6-(4-chlorophenyl)-4-(4-methoxyphenyl)- 2-oxocyclohex-3-ene-1- carboxylate, Fun et al., 2009, ethyl 4-(4-methoxyphenyl)-2-oxo-6- phenylcyclohex-3-ene-1-carboxylate, Fun et al., 2008, ethyl 4-(4-bromophenyl)-6-(4-ethoxyphenyl)- 2-oxocyclo-hex-3-enecarboxylate, Badshah et al., 2009). Here we report the crystal structure of (1RS,6SR) ethyl 4-(4-chlorophenyl)-6-(4-fluorophenyl)-2-oxocyclohex-3-ene-1-carboxylate toluene solvate (I, Scheme 1).
The overall conformation of I (Fig. 1) can be characterized by the dihedral angles between the phenyl rings, of 72.90 (7)°,and between these rings and the plane of cyclohexene ring which are equal to 30.09 (10)° for chlorophenyl ring and 88.13 (6)°for fluorophenyl ring. These values are similar to those found in the structures of related compounds, for instance in methyl4,6-bis(4-fluorophenyl)-2-oxocyclohex- 3-ene-1-carboxylate (Fun et al., 2010) the dihedral angles between fluorophenylrings in two symmetry-independent molecules are 79.7 (2)° and 73.7 (2)°, and the angles between the cyclohexene planeand the fluorophenyl rings are 14.9° and 73.7° in one molecule and 29.9° and 84.0° in the second. In the structure ofethyl 6 - r-(2-chlorophenyl)-2-oxo-4- phenylcyclohex-3-ene-1 - t-carboxylate (Anuradha et al., 2009) appropriate anglesare 81.73 (12)°. 12.75 (14)° and 74.16 (8)°.
The cyclohexene ring adopts slightly distorted sofa conformation, the asymmetry parameter ΔCs3 (Duax & Norton, 1975)
is 6.2°. This is also confirmed by least-squares calculations: five atoms C1 - C5 are almost coplanar, maximum deviation is0.030 (2) Å, while the sixth atom, C6, is by 0.672 (3)Å out of this mean plane.
In the crystal structure the molecules are joined by weak C—H···O, C—H···F and C—H···Cl interactions (Fig. 2). Thesolvent - toluene molecules are disordered over the centre of symmetry. They occupy the voids in the crystal structure andare kept there by means of relatively short and linear C—H···π interactions (H···Cg 2.78 Å, C—H···Cg 155°). An inteerestingfeature of the structure is the presence of linear C—Cl···F—C contacts (F···Cl 3.12 Å, C—Cl···F 157.5 (2)°, C—F···Cl108.3 (2)°). In the CSD (Allen, 2002) there are 196 cases of such contacts shorter than 3.2 Å, and the same directionalpreferences are observed.
Experimental
A mixture of ((2E)-1-(4-chlorophenyl)-3-(4-fluorophenyl)prop-2-en-1-one (0.01 mol) and ethyl acetoacetate (0.01 mol)were refluxed for 2 hr in 10–15 ml of ethanol in the presence of 0.8 ml 10% NaOH. The crystals were obtained by a slowevaporation from toluene solution. C21H18ClFO3.C7H8: C: 72.26 (72.33); H:5.59 (5.64); m.p. 346 K.
Hydrogen atoms from solvent molecule were located geometrically (C(methyl)-H 0.98 Å, C(arom)-H 0.95 Å) and refinedas a riding model; the Uiso values of H atoms were set at 1.2 (1.5 for CH3 group) times Ueq of their carrier atom. All other
hydrogen atoms were located in difference Fourier maps and isotropically refined.
Figures
Fig. 1. Anisotropic ellipsoid representation of the components of I together with atom la-belling scheme. The ellipsoids are drawn at 50% probability level, hydrogen atoms are de-picted as spheres with arbitrary radii; only one of the disordered toluene molecules is shown.[Symmetry code: (i) 1 - x,1 - y,2 - z]
Fig. 2. The crystal packing as seen along x-direction. Weak interactions (cf. text) are shown asdashed lines. For the sake of clarity, H atoms not involved in hydrogen interactions have beenomitted .
Refinement on F2 Primary atom site location: structure-invariant directmethods
Least-squares matrix: full Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.042Hydrogen site location: inferred from neighbouringsites
wR(F2) = 0.085H atoms treated by a mixture of independent andconstrained refinement
S = 1.02w = 1/[σ2(Fo
2) + (0.032P)2]where P = (Fo
2 + 2Fc2)/3
4154 reflections (Δ/σ)max < 0.001
341 parameters Δρmax = 0.24 e Å−3
0 restraints Δρmin = −0.28 e Å−3
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 mat-rix. 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; correlationsbetween e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment ofcell 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, convention-
al 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 largeas 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)