organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

Ethyl 4-(4-meth­oxy­phen­yl)-2-oxo-6-phenyl­cyclo­hex-3-ene-1-carboxyl­ate

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bDepartment of Studies in Chemistry, Mangalore University, Mangalagangothri, Mangalore 574 199, India
*Correspondence e-mail: hkfun@usm.my

(Received 14 November 2008; accepted 21 November 2008; online 26 November 2008)

The asymmetric unit of the title compound, C22H22O4, consists of two independent mol­ecules (A and B) which differ significantly in the orientations of ethyl carboxyl­ate groups. The phenyl ring in mol­ecule B is disordered over two orientations with occupancies of 0.55 (2) and 0.45 (2). The cyclo­hexenone ring of both mol­ecules adopts an envelope conformation. The dihedral angle between the two aromatic rings is 81.12 (7)° in mol­ecule A and 70.8 (3)° in mol­ecule B [57.5 (4)° in the minor disorder component]. The crystal structure is stabilized by weak intermolecular C—H⋯O hydrogen bonds and C—H⋯π inter­actions.

Related literature

For general background, see: Kalluraya & Rai (2003[Kalluraya, B. & Rai, G. (2003). Synth. Commun. 33, 3589-3595.]); Kalluraya & Rahiman (2003[Kalluraya, B. & Rahiman, M. A. (2003). Indian J. Chem. Sect. B, 42, 1141-1148.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For ring puckering analysis, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]).

[Scheme 1]

Experimental

Crystal data
  • C22H22O4

  • Mr = 350.40

  • Triclinic, [P \overline 1]

  • a = 9.6095 (2) Å

  • b = 12.5386 (3) Å

  • c = 15.9704 (3) Å

  • α = 75.916 (1)°

  • β = 78.879 (1)°

  • γ = 88.413 (1)°

  • V = 1831.00 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 100.0 (1) K

  • 0.50 × 0.28 × 0.24 mm

Data collection
  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.958, Tmax = 0.980

  • 57259 measured reflections

  • 13169 independent reflections

  • 9552 reflections with I > 2σ(I)

  • Rint = 0.032

Refinement
  • R[F2 > 2σ(F2)] = 0.058

  • wR(F2) = 0.169

  • S = 1.02

  • 13169 reflections

  • 528 parameters

  • 144 restraints

  • H-atom parameters constrained

  • Δρmax = 0.92 e Å−3

  • Δρmin = −0.28 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C3A—H3AA⋯O2Bi 1.00 2.57 3.4093 (18) 142
C5A—H5AA⋯O4Bii 0.95 2.55 3.3630 (17) 143
C8A—H8AA⋯O4Bii 0.95 2.31 3.2446 (18) 166
C14B—H14B⋯O2Ai 0.95 2.58 3.500 (5) 163
C16A—H16A⋯O2Biii 0.95 2.47 3.2789 (18) 143
C17B—H17B⋯O3Aiv 0.95 2.47 3.116 (9) 125
C21B—H21DCg1v 0.98 2.85 3.811 (2) 167
C22B—H22DCg2vi 0.98 2.87 3.644 (4) 137
Symmetry codes: (i) -x, -y+1, -z+2; (ii) -x+1, -y+1, -z+2; (iii) x, y+1, z-1; (iv) x, y-1, z; (v) x+1, y, z; (vi) -x, -y, -z+2. Cg1 and Cg2 are the centroids of the C13A–C18A and C13B–C18B rings, respectively.

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]).

Supporting information


Comment top

Cyclohexenone is an organic compound which is a versatile intermediate used in the synthesis of a variety of chemical products such as pharmaceuticals and fragrances. The Robinson annulation is an organic reaction used to create a cyclic six-membered, β-unsaturated ketones. Different methods including solvent-free synthesis of these compounds have been reported (Kalluraya & Rai, 2003). Cyclohexenone and their derivatives are known for anti-inflammatory and analegesic activities (Kalluraya & Rahiman, 2003).

The asymmetric unit of the title compound consists of two independent molecules (Fig. 1). Bond lengths in the molecules (Fig. 1) are found to have normal values (Allen et al., 1987). The two independent molecules differ significantly in the orientations of ethyl carboxylate groups [C4A—C3A—C19A—O1A = 63.32 (14)° and C4B—C3B—C19B—O1B = 105.25 (13)°]. The phenyl ring in molecule B is disordered over two orientations. The cyclohexenone ring in both molecules adopts an envelope conformation, with puckering parameters Q = 0.494 (1) Å, θ = 52.1 (2)° and ϕ = 67.4 (2)° for molecule A, and Q = 0.429 (2) Å, θ = 130.1 (2)° and ϕ = 250.4 (3)° in molecule B (Cremer & Pople, 1975). The dihedral angle between the two aromatic rings is 81.12 (7)° in molecule A and 70.8 (3)° in molecule B [57.5 (4)° in the minor disorder component].

The crystal structure is stabilized by intermolecular weak C—H···O hydrogen bonds (Table 1) and C—H···π interactions (Fig 2).

Related literature top

For general background, see: Kalluraya & Rai (2003); Kalluraya & Rahiman (2003). For bond-length data, see: Allen et al. (1987). For ring puckering analysis, see: Cremer & Pople (1975). Cg1 and Cg2 are the centroids of the C13A–C18A and C13B–C18B rings, respectively.

Experimental top

To a solution of 1-phenyl-3-anisyl-prop-2-en-1-one (0.01 mol) in dry acetone (25 ml), dry potassium carbonate (0.04 mol) and ethyl acetoacetate (0.02 mol) in dry acetone (25 ml) were added. The mixture was stirred at room temperature for overnight and was filtered. The solvent from the filtrate on evaporation gave a solid which was recrystallized from a mixture of ethanol-dioxane.

Refinement top

The phenyl ring in molecule B is disordered over two orientations with refined occupancies of 0.545 (17) and 0.455 (17). The C-C bond lengths involving the disordered atoms were restrained to be equal and also the Uij components of the disordered atoms were approximated to isotropic behaviour. The two orientations were restrained to be planar. H atoms were positioned geometrically (C-H = 0.95–1.00 Å) and refined using a riding model, with Uiso(H) = 1.2Ueq(C) and 1.5Ueq(Cmethyl). A rotating group model was used for the methyl groups. The highest four difference peaks were observed at 0.92, 0.83, 0.87 and 84 Å, respectively, from atoms C3B, C2B, C2A and C3A. No suitable disorder model involving these atoms were found.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme. Both disorder component of an independent molecule are shown.
[Figure 2] Fig. 2. The crystal packing of the title compound, viewed down the c axis. Only the major disorder component of an independent molecule is shown.
Ethyl 4-(4-methoxyphenyl)-2-oxo-6-phenylcyclohex-3-ene-1-carboxylate top
Crystal data top
C22H22O4Z = 4
Mr = 350.40F(000) = 744
Triclinic, P1Dx = 1.271 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 9.6095 (2) ÅCell parameters from 9088 reflections
b = 12.5386 (3) Åθ = 2.3–33.8°
c = 15.9704 (3) ŵ = 0.09 mm1
α = 75.916 (1)°T = 100 K
β = 78.879 (1)°Block, colourless
γ = 88.413 (1)°0.50 × 0.28 × 0.24 mm
V = 1831.00 (7) Å3
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
13169 independent reflections
Radiation source: fine-focus sealed tube9552 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.032
ϕ and ω scansθmax = 32.5°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
h = 1414
Tmin = 0.958, Tmax = 0.980k = 1818
57259 measured reflectionsl = 2424
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.058Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.169H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0817P)2 + 0.7633P]
where P = (Fo2 + 2Fc2)/3
13169 reflections(Δ/σ)max = 0.001
528 parametersΔρmax = 0.92 e Å3
144 restraintsΔρmin = 0.28 e Å3
Crystal data top
C22H22O4γ = 88.413 (1)°
Mr = 350.40V = 1831.00 (7) Å3
Triclinic, P1Z = 4
a = 9.6095 (2) ÅMo Kα radiation
b = 12.5386 (3) ŵ = 0.09 mm1
c = 15.9704 (3) ÅT = 100 K
α = 75.916 (1)°0.50 × 0.28 × 0.24 mm
β = 78.879 (1)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
13169 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
9552 reflections with I > 2σ(I)
Tmin = 0.958, Tmax = 0.980Rint = 0.032
57259 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.058144 restraints
wR(F2) = 0.169H-atom parameters constrained
S = 1.02Δρmax = 0.92 e Å3
13169 reflectionsΔρmin = 0.28 e Å3
528 parameters
Special details top

Experimental. The data was collected with the Oxford Cyrosystem Cobra low-temperature attachment.

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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*/UeqOcc. (<1)
O1A0.40902 (11)0.86874 (9)0.67186 (6)0.0307 (2)
O2A0.31593 (10)0.42017 (8)1.15549 (6)0.02388 (18)
O3A0.30572 (13)1.01757 (9)0.60083 (7)0.0387 (3)
O4A0.26641 (11)0.94799 (9)0.83284 (6)0.0292 (2)
C1A0.01076 (13)0.73536 (10)0.78085 (8)0.0204 (2)
H1AA0.09010.78210.76340.024*
H1AB0.03210.65930.77890.024*
C2A0.12583 (13)0.77666 (10)0.71543 (8)0.0213 (2)
H2AA0.20280.72530.73230.026*
C3A0.16635 (14)0.89112 (11)0.72390 (8)0.0230 (2)
H3AA0.08780.94240.71010.028*
C4A0.18266 (13)0.88549 (10)0.81804 (8)0.0222 (2)
C5A0.09136 (13)0.80804 (10)0.88799 (8)0.0206 (2)
H5AA0.09600.80710.94710.025*
C6A0.00023 (12)0.73693 (10)0.87393 (7)0.0182 (2)
C7A0.08885 (12)0.65785 (10)0.94693 (7)0.0180 (2)
C8A0.05882 (13)0.63354 (10)1.03249 (8)0.0209 (2)
H8AA0.01670.67181.04390.025*
C9A0.13674 (13)0.55552 (11)1.09986 (8)0.0220 (2)
H9AA0.11480.54081.15700.026*
C10A0.24827 (12)0.49764 (10)1.08465 (8)0.0190 (2)
C11A0.28153 (13)0.52069 (11)1.00134 (8)0.0214 (2)
H11A0.35800.48280.99060.026*
C12A0.20178 (13)0.59991 (11)0.93360 (8)0.0215 (2)
H12A0.22480.61500.87670.026*
C13A0.11848 (14)0.77910 (11)0.62083 (8)0.0224 (2)
C14A0.02075 (16)0.84157 (12)0.57676 (9)0.0283 (3)
H14A0.04600.88360.60660.034*
C15A0.01971 (17)0.84323 (12)0.48886 (9)0.0314 (3)
H15A0.04770.88590.45940.038*
C16A0.11732 (17)0.78234 (13)0.44497 (9)0.0310 (3)
H16A0.11640.78240.38560.037*
C17A0.21553 (17)0.72178 (14)0.48779 (10)0.0333 (3)
H17A0.28330.68080.45750.040*
C18A0.21615 (15)0.72015 (12)0.57507 (9)0.0291 (3)
H18A0.28460.67790.60380.035*
C19A0.30060 (15)0.93526 (11)0.65901 (8)0.0261 (3)
C20A0.53784 (18)0.89483 (17)0.60642 (11)0.0431 (4)
H20A0.58320.96280.61060.052*
H20B0.51680.90620.54660.052*
C21A0.6333 (2)0.7997 (2)0.62443 (14)0.0585 (6)
H21A0.71960.81170.57890.088*
H21B0.58450.73220.62410.088*
H21C0.65850.79250.68210.088*
C22A0.42143 (15)0.35266 (12)1.14049 (9)0.0284 (3)
H22A0.45460.29531.19410.043*
H22B0.38060.31841.09250.043*
H22C0.50150.39801.12450.043*
O1B0.82102 (11)0.36693 (9)0.71886 (8)0.0337 (2)
O2B0.03578 (12)0.11336 (9)1.25183 (7)0.0331 (2)
O3B0.67843 (13)0.47429 (10)0.79017 (8)0.0387 (3)
O4B0.77153 (12)0.27422 (10)0.92874 (8)0.0373 (3)
C1B0.38209 (13)0.19261 (11)0.88538 (8)0.0232 (2)
H1BA0.27990.20990.89430.028*
H1BB0.39530.13120.85580.028*
C2B0.46513 (14)0.29275 (12)0.82477 (9)0.0260 (3)
H2BA0.43470.35770.84930.031*
C3B0.62513 (14)0.27907 (11)0.82326 (10)0.0268 (3)
H3BA0.66040.22050.79210.032*
C4B0.65702 (15)0.24696 (12)0.91615 (10)0.0283 (3)
C5B0.55338 (14)0.18059 (11)0.98555 (9)0.0256 (3)
H5BA0.57740.15381.04180.031*
C6B0.42349 (13)0.15470 (10)0.97426 (8)0.0219 (2)
C7B0.32038 (14)0.08596 (10)1.04606 (8)0.0231 (2)
C8B0.32756 (16)0.07361 (12)1.13529 (9)0.0281 (3)
H8BA0.39990.11171.15000.034*
C9B0.23180 (17)0.00737 (12)1.20146 (9)0.0306 (3)
H9BA0.23840.00061.26110.037*
C10B0.12475 (15)0.05007 (11)1.18154 (9)0.0263 (3)
C11B0.11508 (14)0.03927 (12)1.09398 (9)0.0262 (3)
H11B0.04280.07781.07960.031*
C12B0.21182 (14)0.02814 (11)1.02784 (9)0.0248 (2)
H12B0.20420.03530.96830.030*
C13B0.4318 (8)0.3146 (4)0.7363 (6)0.0160 (10)0.545 (17)
C14B0.3759 (8)0.4132 (4)0.6948 (3)0.0288 (9)0.545 (17)
H14B0.36050.47070.72460.035*0.545 (17)
C15B0.3424 (9)0.4304 (4)0.6127 (3)0.0367 (11)0.545 (17)
H15B0.30500.49920.58770.044*0.545 (17)
C16B0.3613 (9)0.3510 (6)0.5657 (5)0.0338 (12)0.545 (17)
H16B0.33580.36630.50940.041*0.545 (17)
C17B0.4160 (12)0.2501 (7)0.5978 (5)0.0249 (11)0.545 (17)
H17B0.43670.19440.56640.030*0.545 (17)
C18B0.4363 (14)0.2418 (9)0.6820 (6)0.035 (2)0.545 (17)
H18B0.45870.16930.71010.042*0.545 (17)
C13C0.4419 (11)0.3148 (7)0.7251 (8)0.033 (2)0.455 (17)
C14C0.4258 (11)0.4248 (6)0.6876 (4)0.0334 (13)0.455 (17)
H14C0.42840.47950.71940.040*0.455 (17)
C15C0.4053 (12)0.4520 (6)0.6006 (4)0.0403 (16)0.455 (17)
H15C0.39680.52680.57110.048*0.455 (17)
C16C0.3975 (10)0.3702 (8)0.5579 (6)0.0361 (16)0.455 (17)
H16C0.38330.38550.49890.043*0.455 (17)
C17C0.4117 (16)0.2646 (9)0.6059 (7)0.037 (2)0.455 (17)
H17C0.39220.20860.57880.044*0.455 (17)
C18C0.4503 (14)0.2261 (9)0.6885 (6)0.0201 (12)0.455 (17)
H18C0.47670.15350.71370.024*0.455 (17)
C19B0.70784 (15)0.38573 (12)0.77640 (10)0.0288 (3)
C20B0.91687 (18)0.45985 (15)0.67563 (13)0.0416 (4)
H20C1.01120.43250.65380.050*
H20D0.92810.50220.71890.050*
C21B0.8642 (2)0.53375 (16)0.60068 (12)0.0456 (4)
H21D0.93180.59510.57320.068*
H21E0.77180.56230.62230.068*
H21F0.85430.49240.55730.068*
C22B0.06909 (17)0.18023 (14)1.23449 (11)0.0366 (3)
H22D0.12130.22521.29020.055*
H22E0.02230.22831.19800.055*
H22F0.13520.13281.20340.055*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O1A0.0293 (5)0.0386 (6)0.0216 (4)0.0049 (4)0.0003 (4)0.0053 (4)
O2A0.0278 (4)0.0217 (4)0.0209 (4)0.0044 (3)0.0052 (3)0.0017 (3)
O3A0.0524 (7)0.0269 (5)0.0314 (6)0.0069 (5)0.0031 (5)0.0001 (4)
O4A0.0363 (5)0.0302 (5)0.0228 (4)0.0127 (4)0.0039 (4)0.0094 (4)
C1A0.0222 (5)0.0234 (6)0.0168 (5)0.0032 (4)0.0050 (4)0.0059 (4)
C2A0.0248 (5)0.0220 (5)0.0178 (5)0.0019 (4)0.0046 (4)0.0057 (4)
C3A0.0283 (6)0.0218 (6)0.0195 (5)0.0026 (5)0.0042 (4)0.0062 (4)
C4A0.0262 (6)0.0233 (6)0.0183 (5)0.0033 (5)0.0033 (4)0.0079 (4)
C5A0.0233 (5)0.0238 (6)0.0156 (5)0.0029 (4)0.0027 (4)0.0067 (4)
C6A0.0182 (5)0.0204 (5)0.0171 (5)0.0012 (4)0.0042 (4)0.0061 (4)
C7A0.0171 (5)0.0206 (5)0.0170 (5)0.0009 (4)0.0037 (4)0.0056 (4)
C8A0.0207 (5)0.0239 (6)0.0200 (5)0.0018 (4)0.0066 (4)0.0067 (4)
C9A0.0244 (5)0.0246 (6)0.0181 (5)0.0004 (4)0.0078 (4)0.0045 (4)
C10A0.0197 (5)0.0179 (5)0.0192 (5)0.0014 (4)0.0038 (4)0.0041 (4)
C11A0.0193 (5)0.0248 (6)0.0210 (5)0.0024 (4)0.0061 (4)0.0049 (4)
C12A0.0198 (5)0.0263 (6)0.0191 (5)0.0016 (4)0.0061 (4)0.0046 (4)
C13A0.0278 (6)0.0233 (6)0.0168 (5)0.0059 (5)0.0049 (4)0.0051 (4)
C14A0.0340 (7)0.0278 (6)0.0248 (6)0.0019 (5)0.0084 (5)0.0078 (5)
C15A0.0421 (8)0.0286 (7)0.0237 (6)0.0020 (6)0.0129 (6)0.0015 (5)
C16A0.0419 (8)0.0354 (7)0.0163 (5)0.0095 (6)0.0061 (5)0.0055 (5)
C17A0.0356 (7)0.0424 (8)0.0255 (6)0.0003 (6)0.0043 (5)0.0164 (6)
C18A0.0326 (7)0.0345 (7)0.0243 (6)0.0012 (6)0.0094 (5)0.0118 (5)
C19A0.0341 (7)0.0251 (6)0.0190 (5)0.0091 (5)0.0016 (5)0.0067 (5)
C20A0.0326 (7)0.0604 (11)0.0305 (8)0.0117 (7)0.0078 (6)0.0094 (7)
C21A0.0303 (8)0.0938 (17)0.0459 (11)0.0043 (9)0.0024 (7)0.0146 (11)
C22A0.0315 (6)0.0246 (6)0.0281 (6)0.0078 (5)0.0072 (5)0.0025 (5)
O1B0.0325 (5)0.0284 (5)0.0403 (6)0.0011 (4)0.0040 (4)0.0110 (4)
O2B0.0379 (5)0.0327 (5)0.0260 (5)0.0015 (4)0.0083 (4)0.0003 (4)
O3B0.0427 (6)0.0348 (6)0.0435 (6)0.0031 (5)0.0090 (5)0.0181 (5)
O4B0.0319 (5)0.0417 (6)0.0440 (6)0.0052 (5)0.0215 (5)0.0093 (5)
C1B0.0226 (5)0.0267 (6)0.0234 (6)0.0011 (5)0.0094 (4)0.0083 (5)
C2B0.0253 (6)0.0276 (6)0.0289 (6)0.0023 (5)0.0093 (5)0.0109 (5)
C3B0.0252 (6)0.0259 (6)0.0338 (7)0.0018 (5)0.0103 (5)0.0124 (5)
C4B0.0260 (6)0.0295 (7)0.0344 (7)0.0026 (5)0.0146 (5)0.0108 (5)
C5B0.0294 (6)0.0249 (6)0.0280 (6)0.0044 (5)0.0144 (5)0.0105 (5)
C6B0.0257 (6)0.0210 (5)0.0234 (6)0.0051 (4)0.0096 (4)0.0101 (4)
C7B0.0279 (6)0.0220 (6)0.0232 (6)0.0055 (5)0.0097 (5)0.0093 (5)
C8B0.0376 (7)0.0260 (6)0.0254 (6)0.0020 (5)0.0142 (5)0.0088 (5)
C9B0.0426 (8)0.0284 (7)0.0236 (6)0.0045 (6)0.0137 (6)0.0067 (5)
C10B0.0305 (6)0.0247 (6)0.0237 (6)0.0080 (5)0.0079 (5)0.0046 (5)
C11B0.0258 (6)0.0289 (6)0.0263 (6)0.0039 (5)0.0083 (5)0.0088 (5)
C12B0.0259 (6)0.0285 (6)0.0230 (6)0.0041 (5)0.0089 (5)0.0093 (5)
C13B0.0167 (15)0.0147 (16)0.017 (2)0.0025 (12)0.0014 (12)0.0057 (12)
C14B0.031 (2)0.0253 (15)0.0305 (15)0.0005 (16)0.0052 (16)0.0084 (11)
C15B0.049 (3)0.0263 (16)0.0327 (17)0.0033 (17)0.0118 (18)0.0008 (12)
C16B0.043 (3)0.036 (2)0.0238 (19)0.005 (2)0.013 (2)0.0042 (15)
C17B0.042 (2)0.0218 (18)0.0146 (16)0.0060 (16)0.0051 (15)0.0108 (18)
C18B0.049 (4)0.018 (3)0.035 (3)0.001 (2)0.014 (2)0.0042 (18)
C13C0.030 (3)0.055 (4)0.015 (3)0.017 (2)0.008 (2)0.003 (2)
C14C0.040 (3)0.035 (2)0.028 (2)0.006 (2)0.011 (2)0.0114 (17)
C15C0.054 (4)0.035 (2)0.031 (2)0.014 (3)0.012 (2)0.0056 (17)
C16C0.033 (3)0.050 (4)0.026 (2)0.005 (2)0.012 (2)0.006 (3)
C17C0.045 (3)0.041 (4)0.032 (3)0.016 (3)0.002 (2)0.028 (2)
C18C0.033 (2)0.012 (3)0.017 (2)0.0041 (19)0.0100 (16)0.0024 (19)
C19B0.0255 (6)0.0328 (7)0.0323 (7)0.0010 (5)0.0109 (5)0.0116 (6)
C20B0.0308 (7)0.0402 (9)0.0492 (10)0.0045 (6)0.0038 (7)0.0047 (7)
C21B0.0490 (10)0.0414 (9)0.0433 (9)0.0057 (8)0.0069 (8)0.0050 (7)
C22B0.0342 (7)0.0356 (8)0.0353 (8)0.0006 (6)0.0090 (6)0.0021 (6)
Geometric parameters (Å, º) top
O1A—C19A1.3320 (18)C1B—C6B1.5092 (17)
O1A—C20A1.4452 (18)C1B—C2B1.5220 (19)
O2A—C10A1.3648 (15)C1B—H1BA0.99
O2A—C22A1.4289 (16)C1B—H1BB0.99
O3A—C19A1.2038 (17)C2B—C13B1.468 (8)
O4A—C4A1.2313 (15)C2B—C3B1.5385 (19)
C1A—C6A1.5143 (16)C2B—C13C1.607 (12)
C1A—C2A1.5257 (17)C2B—H2BA1.00
C1A—H1AA0.99C3B—C19B1.524 (2)
C1A—H1AB0.99C3B—C4B1.528 (2)
C2A—C13A1.5189 (16)C3B—H3BA1.00
C2A—C3A1.5412 (17)C4B—C5B1.444 (2)
C2A—H2AA1.00C5B—C6B1.3541 (18)
C3A—C19A1.5131 (18)C5B—H5BA0.95
C3A—C4A1.5259 (17)C6B—C7B1.4723 (19)
C3A—H3AA1.00C7B—C12B1.4000 (18)
C4A—C5A1.4498 (17)C7B—C8B1.4104 (18)
C5A—C6A1.3554 (16)C8B—C9B1.376 (2)
C5A—H5AA0.95C8B—H8BA0.95
C6A—C7A1.4726 (16)C9B—C10B1.399 (2)
C7A—C12A1.3997 (16)C9B—H9BA0.95
C7A—C8A1.4099 (16)C10B—C11B1.3927 (18)
C8A—C9A1.3757 (18)C11B—C12B1.387 (2)
C8A—H8AA0.95C11B—H11B0.95
C9A—C10A1.4013 (17)C12B—H12B0.95
C9A—H9AA0.95C13B—C18B1.398 (8)
C10A—C11A1.3884 (16)C13B—C14B1.399 (6)
C11A—C12A1.3941 (17)C14B—C15B1.375 (6)
C11A—H11A0.95C14B—H14B0.95
C12A—H12A0.95C15B—C16B1.373 (7)
C13A—C18A1.3861 (19)C15B—H15B0.95
C13A—C14A1.3917 (19)C16B—C17B1.376 (8)
C14A—C15A1.4008 (19)C16B—H16B0.95
C14A—H14A0.95C17B—C18B1.376 (8)
C15A—C16A1.386 (2)C17B—H17B0.95
C15A—H15A0.95C18B—H18B0.95
C16A—C17A1.375 (2)C13C—C18C1.371 (9)
C16A—H16A0.95C13C—C14C1.381 (9)
C17A—C18A1.3903 (19)C14C—C15C1.399 (7)
C17A—H17A0.95C14C—H14C0.95
C18A—H18A0.95C15C—C16C1.374 (8)
C20A—C21A1.491 (3)C15C—H15C0.95
C20A—H20A0.99C16C—C17C1.377 (10)
C20A—H20B0.99C16C—H16C0.95
C21A—H21A0.98C17C—C18C1.407 (10)
C21A—H21B0.98C17C—H17C0.95
C21A—H21C0.98C18C—H18C0.95
C22A—H22A0.98C20B—C21B1.488 (3)
C22A—H22B0.98C20B—H20C0.99
C22A—H22C0.98C20B—H20D0.99
O1B—C19B1.3373 (18)C21B—H21D0.98
O1B—C20B1.451 (2)C21B—H21E0.98
O2B—C10B1.3619 (18)C21B—H21F0.98
O2B—C22B1.436 (2)C22B—H22D0.98
O3B—C19B1.1995 (18)C22B—H22E0.98
O4B—C4B1.2279 (16)C22B—H22F0.98
C19A—O1A—C20A116.22 (12)C13B—C2B—C13C4.7 (6)
C10A—O2A—C22A117.00 (10)C1B—C2B—C13C113.0 (4)
C6A—C1A—C2A112.11 (9)C3B—C2B—C13C107.6 (4)
C6A—C1A—H1AA109.2C13B—C2B—H2BA107.6
C2A—C1A—H1AA109.2C1B—C2B—H2BA107.6
C6A—C1A—H1AB109.2C3B—C2B—H2BA107.6
C2A—C1A—H1AB109.2C13C—C2B—H2BA110.3
H1AA—C1A—H1AB107.9C19B—C3B—C4B106.55 (11)
C13A—C2A—C1A113.81 (10)C19B—C3B—C2B111.56 (11)
C13A—C2A—C3A110.83 (10)C4B—C3B—C2B111.59 (12)
C1A—C2A—C3A109.34 (10)C19B—C3B—H3BA109.0
C13A—C2A—H2AA107.5C4B—C3B—H3BA109.0
C1A—C2A—H2AA107.5C2B—C3B—H3BA109.0
C3A—C2A—H2AA107.5O4B—C4B—C5B122.18 (13)
C19A—C3A—C4A111.12 (10)O4B—C4B—C3B119.32 (14)
C19A—C3A—C2A110.74 (10)C5B—C4B—C3B118.42 (11)
C4A—C3A—C2A110.11 (10)C6B—C5B—C4B123.11 (12)
C19A—C3A—H3AA108.3C6B—C5B—H5BA118.4
C4A—C3A—H3AA108.3C4B—C5B—H5BA118.4
C2A—C3A—H3AA108.3C5B—C6B—C7B121.91 (11)
O4A—C4A—C5A122.27 (11)C5B—C6B—C1B120.34 (12)
O4A—C4A—C3A120.41 (11)C7B—C6B—C1B117.70 (11)
C5A—C4A—C3A117.25 (10)C12B—C7B—C8B117.19 (12)
C6A—C5A—C4A123.75 (11)C12B—C7B—C6B120.73 (11)
C6A—C5A—H5AA118.1C8B—C7B—C6B122.07 (12)
C4A—C5A—H5AA118.1C9B—C8B—C7B121.25 (13)
C5A—C6A—C7A121.98 (10)C9B—C8B—H8BA119.4
C5A—C6A—C1A119.92 (11)C7B—C8B—H8BA119.4
C7A—C6A—C1A118.08 (10)C8B—C9B—C10B120.48 (12)
C12A—C7A—C8A117.23 (11)C8B—C9B—H9BA119.8
C12A—C7A—C6A121.58 (10)C10B—C9B—H9BA119.8
C8A—C7A—C6A121.12 (10)O2B—C10B—C11B124.76 (13)
C9A—C8A—C7A121.32 (11)O2B—C10B—C9B115.76 (12)
C9A—C8A—H8AA119.3C11B—C10B—C9B119.48 (13)
C7A—C8A—H8AA119.3C12B—C11B—C10B119.52 (12)
C8A—C9A—C10A120.40 (11)C12B—C11B—H11B120.2
C8A—C9A—H9AA119.8C10B—C11B—H11B120.2
C10A—C9A—H9AA119.8C11B—C12B—C7B122.08 (12)
O2A—C10A—C11A124.88 (11)C11B—C12B—H12B119.0
O2A—C10A—C9A115.49 (10)C7B—C12B—H12B119.0
C11A—C10A—C9A119.62 (11)C18B—C13B—C14B107.6 (8)
C10A—C11A—C12A119.44 (11)C18B—C13B—C2B128.1 (5)
C10A—C11A—H11A120.3C14B—C13B—C2B124.1 (5)
C12A—C11A—H11A120.3C15B—C14B—C13B122.8 (5)
C11A—C12A—C7A121.98 (11)C15B—C14B—H14B118.6
C11A—C12A—H12A119.0C13B—C14B—H14B118.6
C7A—C12A—H12A119.0C16B—C15B—C14B122.0 (5)
C18A—C13A—C14A118.29 (12)C16B—C15B—H15B119.0
C18A—C13A—C2A118.99 (12)C14B—C15B—H15B119.0
C14A—C13A—C2A122.68 (12)C15B—C16B—C17B121.9 (7)
C13A—C14A—C15A120.77 (13)C15B—C16B—H16B119.1
C13A—C14A—H14A119.6C17B—C16B—H16B119.1
C15A—C14A—H14A119.6C18B—C17B—C16B109.9 (9)
C16A—C15A—C14A119.77 (13)C18B—C17B—H17B125.1
C16A—C15A—H15A120.1C16B—C17B—H17B125.1
C14A—C15A—H15A120.1C17B—C18B—C13B135.3 (10)
C17A—C16A—C15A119.70 (12)C17B—C18B—H18B112.4
C17A—C16A—H16A120.1C13B—C18B—H18B112.4
C15A—C16A—H16A120.1C18C—C13C—C14C130.0 (11)
C16A—C17A—C18A120.39 (14)C18C—C13C—C2B117.1 (7)
C16A—C17A—H17A119.8C14C—C13C—C2B112.7 (7)
C18A—C17A—H17A119.8C13C—C14C—C15C116.8 (7)
C13A—C18A—C17A121.06 (13)C13C—C14C—H14C121.6
C13A—C18A—H18A119.5C15C—C14C—H14C121.6
C17A—C18A—H18A119.5C16C—C15C—C14C119.8 (6)
O3A—C19A—O1A124.84 (13)C16C—C15C—H15C120.1
O3A—C19A—C3A123.63 (14)C14C—C15C—H15C120.1
O1A—C19A—C3A111.44 (11)C15C—C16C—C17C115.8 (8)
O1A—C20A—C21A106.78 (15)C15C—C16C—H16C122.1
O1A—C20A—H20A110.4C17C—C16C—H16C122.1
C21A—C20A—H20A110.4C16C—C17C—C18C130.6 (11)
O1A—C20A—H20B110.4C16C—C17C—H17C114.7
C21A—C20A—H20B110.4C18C—C17C—H17C114.7
H20A—C20A—H20B108.6C13C—C18C—C17C105.8 (11)
C20A—C21A—H21A109.5C13C—C18C—H18C127.1
C20A—C21A—H21B109.5C17C—C18C—H18C127.1
H21A—C21A—H21B109.5O3B—C19B—O1B124.16 (14)
C20A—C21A—H21C109.5O3B—C19B—C3B125.19 (14)
H21A—C21A—H21C109.5O1B—C19B—C3B110.63 (12)
H21B—C21A—H21C109.5O1B—C20B—C21B111.94 (14)
O2A—C22A—H22A109.5O1B—C20B—H20C109.2
O2A—C22A—H22B109.5C21B—C20B—H20C109.2
H22A—C22A—H22B109.5O1B—C20B—H20D109.2
O2A—C22A—H22C109.5C21B—C20B—H20D109.2
H22A—C22A—H22C109.5H20C—C20B—H20D107.9
H22B—C22A—H22C109.5C20B—C21B—H21D109.5
C19B—O1B—C20B116.36 (12)C20B—C21B—H21E109.5
C10B—O2B—C22B117.72 (11)H21D—C21B—H21E109.5
C6B—C1B—C2B114.71 (10)C20B—C21B—H21F109.5
C6B—C1B—H1BA108.6H21D—C21B—H21F109.5
C2B—C1B—H1BA108.6H21E—C21B—H21F109.5
C6B—C1B—H1BB108.6O2B—C22B—H22D109.5
C2B—C1B—H1BB108.6O2B—C22B—H22E109.5
H1BA—C1B—H1BB107.6H22D—C22B—H22E109.5
C13B—C2B—C1B110.9 (3)O2B—C22B—H22F109.5
C13B—C2B—C3B112.2 (3)H22D—C22B—H22F109.5
C1B—C2B—C3B110.68 (11)H22E—C22B—H22F109.5
C6A—C1A—C2A—C13A178.56 (10)C2B—C3B—C4B—O4B151.15 (14)
C6A—C1A—C2A—C3A54.04 (13)C19B—C3B—C4B—C5B153.85 (12)
C13A—C2A—C3A—C19A53.03 (14)C2B—C3B—C4B—C5B31.85 (17)
C1A—C2A—C3A—C19A179.27 (10)O4B—C4B—C5B—C6B176.25 (14)
C13A—C2A—C3A—C4A176.33 (10)C3B—C4B—C5B—C6B6.8 (2)
C1A—C2A—C3A—C4A57.43 (13)C4B—C5B—C6B—C7B179.42 (12)
C19A—C3A—C4A—O4A26.66 (17)C4B—C5B—C6B—C1B1.78 (19)
C2A—C3A—C4A—O4A149.73 (12)C2B—C1B—C6B—C5B22.94 (17)
C19A—C3A—C4A—C5A156.21 (12)C2B—C1B—C6B—C7B159.32 (11)
C2A—C3A—C4A—C5A33.14 (15)C5B—C6B—C7B—C12B157.01 (12)
O4A—C4A—C5A—C6A178.87 (13)C1B—C6B—C7B—C12B20.69 (17)
C3A—C4A—C5A—C6A4.06 (19)C5B—C6B—C7B—C8B21.79 (19)
C4A—C5A—C6A—C7A178.62 (11)C1B—C6B—C7B—C8B160.50 (12)
C4A—C5A—C6A—C1A0.20 (18)C12B—C7B—C8B—C9B0.1 (2)
C2A—C1A—C6A—C5A25.66 (16)C6B—C7B—C8B—C9B178.77 (13)
C2A—C1A—C6A—C7A152.81 (10)C7B—C8B—C9B—C10B0.3 (2)
C5A—C6A—C7A—C12A167.45 (12)C22B—O2B—C10B—C11B4.9 (2)
C1A—C6A—C7A—C12A14.11 (16)C22B—O2B—C10B—C9B175.43 (12)
C5A—C6A—C7A—C8A15.68 (18)C8B—C9B—C10B—O2B179.92 (12)
C1A—C6A—C7A—C8A162.76 (11)C8B—C9B—C10B—C11B0.4 (2)
C12A—C7A—C8A—C9A0.45 (18)O2B—C10B—C11B—C12B179.76 (12)
C6A—C7A—C8A—C9A176.55 (11)C9B—C10B—C11B—C12B0.1 (2)
C7A—C8A—C9A—C10A0.29 (19)C10B—C11B—C12B—C7B0.3 (2)
C22A—O2A—C10A—C11A4.94 (17)C8B—C7B—C12B—C11B0.37 (19)
C22A—O2A—C10A—C9A174.41 (11)C6B—C7B—C12B—C11B178.49 (12)
C8A—C9A—C10A—O2A178.32 (11)C1B—C2B—C13B—C18B52.5 (10)
C8A—C9A—C10A—C11A1.07 (18)C3B—C2B—C13B—C18B71.8 (9)
O2A—C10A—C11A—C12A178.25 (11)C13C—C2B—C13B—C18B65 (6)
C9A—C10A—C11A—C12A1.08 (18)C1B—C2B—C13B—C14B121.2 (6)
C10A—C11A—C12A—C7A0.33 (19)C3B—C2B—C13B—C14B114.5 (6)
C8A—C7A—C12A—C11A0.43 (18)C13C—C2B—C13B—C14B122 (7)
C6A—C7A—C12A—C11A176.55 (11)C18B—C13B—C14B—C15B3.5 (9)
C1A—C2A—C13A—C18A122.41 (13)C2B—C13B—C14B—C15B178.3 (5)
C3A—C2A—C13A—C18A113.87 (14)C13B—C14B—C15B—C16B0.2 (7)
C1A—C2A—C13A—C14A60.06 (16)C14B—C15B—C16B—C17B0.6 (9)
C3A—C2A—C13A—C14A63.66 (16)C15B—C16B—C17B—C18B4.2 (13)
C18A—C13A—C14A—C15A1.1 (2)C16B—C17B—C18B—C13B10 (2)
C2A—C13A—C14A—C15A178.63 (12)C14B—C13B—C18B—C17B9.5 (19)
C13A—C14A—C15A—C16A0.2 (2)C2B—C13B—C18B—C17B176.0 (12)
C14A—C15A—C16A—C17A0.8 (2)C13B—C2B—C13C—C18C111 (7)
C15A—C16A—C17A—C18A0.9 (2)C1B—C2B—C13C—C18C46.3 (10)
C14A—C13A—C18A—C17A1.0 (2)C3B—C2B—C13C—C18C76.2 (9)
C2A—C13A—C18A—C17A178.61 (13)C13B—C2B—C13C—C14C73 (6)
C16A—C17A—C18A—C13A0.0 (2)C1B—C2B—C13C—C14C137.9 (6)
C20A—O1A—C19A—O3A4.8 (2)C3B—C2B—C13C—C14C99.7 (7)
C20A—O1A—C19A—C3A171.95 (12)C18C—C13C—C14C—C15C4.7 (13)
C4A—C3A—C19A—O3A119.90 (14)C2B—C13C—C14C—C15C179.9 (5)
C2A—C3A—C19A—O3A117.39 (14)C13C—C14C—C15C—C16C2.1 (8)
C4A—C3A—C19A—O1A63.32 (14)C14C—C15C—C16C—C17C0.3 (11)
C2A—C3A—C19A—O1A59.39 (14)C15C—C16C—C17C—C18C8.9 (19)
C19A—O1A—C20A—C21A169.57 (14)C14C—C13C—C18C—C17C11.1 (17)
C6B—C1B—C2B—C13B172.3 (3)C2B—C13C—C18C—C17C173.9 (9)
C6B—C1B—C2B—C3B47.14 (15)C16C—C17C—C18C—C13C13 (2)
C6B—C1B—C2B—C13C167.8 (4)C20B—O1B—C19B—O3B4.1 (2)
C13B—C2B—C3B—C19B65.7 (2)C20B—O1B—C19B—C3B174.31 (12)
C1B—C2B—C3B—C19B169.88 (11)C4B—C3B—C19B—O3B73.10 (17)
C13C—C2B—C3B—C19B66.3 (3)C2B—C3B—C19B—O3B48.92 (19)
C13B—C2B—C3B—C4B175.3 (2)C4B—C3B—C19B—O1B105.25 (13)
C1B—C2B—C3B—C4B50.81 (14)C2B—C3B—C19B—O1B132.73 (12)
C13C—C2B—C3B—C4B174.7 (3)C19B—O1B—C20B—C21B80.67 (19)
C19B—C3B—C4B—O4B29.15 (18)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3A—H3AA···O2Bi1.002.573.4093 (18)142
C5A—H5AA···O4Bii0.952.553.3630 (17)143
C8A—H8AA···O4Bii0.952.313.2446 (18)166
C14B—H14B···O2Ai0.952.583.500 (5)163
C16A—H16A···O2Biii0.952.473.2789 (18)143
C17B—H17B···O3Aiv0.952.473.116 (9)125
C21B—H21D···Cg1v0.982.853.811 (2)167
C22B—H22D···Cg2vi0.982.873.644 (4)137
Symmetry codes: (i) x, y+1, z+2; (ii) x+1, y+1, z+2; (iii) x, y+1, z1; (iv) x, y1, z; (v) x+1, y, z; (vi) x, y, z+2.

Experimental details

Crystal data
Chemical formulaC22H22O4
Mr350.40
Crystal system, space groupTriclinic, P1
Temperature (K)100
a, b, c (Å)9.6095 (2), 12.5386 (3), 15.9704 (3)
α, β, γ (°)75.916 (1), 78.879 (1), 88.413 (1)
V3)1831.00 (7)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.50 × 0.28 × 0.24
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.958, 0.980
No. of measured, independent and
observed [I > 2σ(I)] reflections
57259, 13169, 9552
Rint0.032
(sin θ/λ)max1)0.756
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.058, 0.169, 1.02
No. of reflections13169
No. of parameters528
No. of restraints144
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.92, 0.28

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3A—H3AA···O2Bi1.002.573.4093 (18)142
C5A—H5AA···O4Bii0.952.553.3630 (17)143
C8A—H8AA···O4Bii0.952.313.2446 (18)166
C14B—H14B···O2Ai0.952.583.500 (5)163
C16A—H16A···O2Biii0.952.473.2789 (18)143
C17B—H17B···O3Aiv0.952.473.116 (9)125
C21B—H21D···Cg1v0.982.853.811 (2)167
C22B—H22D···Cg2vi0.982.873.644 (4)137
Symmetry codes: (i) x, y+1, z+2; (ii) x+1, y+1, z+2; (iii) x, y+1, z1; (iv) x, y1, z; (v) x+1, y, z; (vi) x, y, z+2.
 

Footnotes

Permanent address: Department of Physics, Karunya University, Karunya Nagar, Coimbatore 641 114, India.

Acknowledgements

HKF and SRJ thank the Malaysian Government and Universiti Sains Malaysia for the Science Fund grant No. 305/PFIZIK/613312. SRJ thanks Universiti Sains Malaysia for a post–doctoral research fellowship. HKF thanks Universiti Sains Malaysia for the Research University Golden Goose Grant No. 1001/PFIZIK/811012.

References

First citationAllen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19.  CrossRef Web of Science Google Scholar
First citationBruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationCremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354–1358.  CrossRef CAS Web of Science Google Scholar
First citationKalluraya, B. & Rahiman, M. A. (2003). Indian J. Chem. Sect. B, 42, 1141–1148.  Google Scholar
First citationKalluraya, B. & Rai, G. (2003). Synth. Commun. 33, 3589–3595.  Web of Science CrossRef CAS Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSpek, A. L. (2003). J. Appl. Cryst. 36, 7–13.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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