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Acta Cryst.(2003). E59, o463±o465 DOI: 10.1107/S1600536803005361 Savaridasson Jose Kavithaet al. C19H18Cl2O2

o463

organic papers

Acta Crystallographica Section E

Structure Reports

Online ISSN 1600-5368

r

-2,

c

-6-Bis(4-chlorophenyl)-

t

-3,

t

-5-dimethyl-tetrahydropyran-4-one

Savaridasson Jose Kavitha,a

Thanjavur Ramabhadran

Sarangarajan,bKanagasabapathy

Thanikasalam,aKrishnaswamy

Panchanatheswarana* and

Ramasubbu Jeyaramana

aDepartment of Chemistry, Bharathidasan University, Tiruchirappalli 620 024, India, and bDepartment of Chemistry, Shanmuga Arts Science Technology and Research Academy (SASTRA), Tirumalaisamudram, Thanjavur, India

Correspondence e-mail: panch45@rediffmail.com

Key indicators

Single-crystal X-ray study

T= 293 K

Mean(C±C) = 0.004 AÊ

Rfactor = 0.051

wRfactor = 0.140

Data-to-parameter ratio = 15.2

For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e.

#2003 International Union of Crystallography Printed in Great Britain ± all rights reserved

The molecular structure of the title compound, C19H18Cl2O2,

reveals a distorted chair conformation for the pyran ring, in which the methyl and 4-chlorophenyl groups occupy equa-torial positions. The molecule is devoid of strong intramolec-ular interactions. In the crystal structure, the molecules form zigzag layers which are held together by CÐH interac-tions.

Comment

The title molecule, (I), contains two pairs of chiral C atoms with identical groups on each. There can be as many as four racemic modi®cations and twomesoforms for the molecule (Eliel, 1962). This investigation was undertaken to assign the con®guration and conformation of the most stable form in the solid state.

The saturated pyran ring adopts a distorted chair conformation, as shown by the torsion angles around the bonds involving the ring atoms. These torsion angles deviate from the ideal value of 56 reported for the chair

conforma-tion of cyclohexane (Kalsi, 1997). The CÐC bond lengths of the aryl rings are in the range 1.362 (4)±1.391 (4) AÊ, while the bond angles are in the range 118.3 (3)±121.4 (4). The

con®gurations of the chiral atoms C2, C3, C5 and C6 are found to beR,S,RandS, respectively. The equatorial dispositions of the methyl and 4-chlorophenyl groups are revealed by the torsion angles involving the exo atom and the other three ring atoms; these vary fromÿ167.9 (2) to 178.3 (2), as observed

also in a pentasubstituted cyclohexan-1-one derivative (Sarangarajanet al., 2002).

In the crystal structure, the molecules are aggregated into zigzag layers extended over theacplane. Within the layer, a Cl Cl short contact of 3.406 (2) AÊ is observed between atoms Cl1 and Cl2i[symmetry code: (i)ÿ1

2ÿx, ÿy,ÿ12+z].

Adjacent layers are linked through CÐH interactions,viz. C3ÐH3 Cg, with H3 Cg= 2.72 AÊ, C3 Cg= 3.631 (3) AÊ and C3ÐH3 Cg= 154, whereCgdenotes the centroid of

the C16±C21 aryl ring of the molecule at (ÿx,1

2+y,12ÿz). The

molecules are also held together by weak interactions (Jeffrey & Saenger, 1991) between C2 and O8ii[3.373 (4) AÊ; symmetry

code: (ii)ÿx+1

2,yÿ12,z+12].

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organic papers

o464

Savaridasson Jose Kavithaet al. C19H18Cl2O2 Acta Cryst.(2003). E59, o463±o465

The title compound is isomorphous with the analogous

p-tolyl derivative, r-2,c-6-bis(p-tolyl)-t-3,t -5-dimethyltetra-hydropyran-4-one (Krishnamoorthy et al., 2003), with very similar crystal and molecular structures. The torsion angles around the CÐC bonds of the tetrahydropyran ring are not signi®cantly different in the two structures. This reveals no conformational changes due to the replacement of methyl by Cl atoms in the title molecule. The gas-phase conformation obtained from AM1 calculations is very similar to that observed in the solid state. The calculated heat of formation,

ÿ48.5 kcal molÿ1, for the compound reveals its inherent

molecular stability.

Experimental

The title compound was prepared by the condensation of pentan-3-one and 4-chlorobenzaldehyde in a 1:2 molar ratio in methanol, as reported by Baliah & Mangalam (1978). Diffraction-quality crystals were obtained by recrystallization of the crude product from ethanol.

Crystal data

C19H18Cl2O2

Mr= 349.23

Orthorhombic,Pbca a= 15.013 (1) AÊ

b= 9.1230 (16) AÊ

c= 25.462 (4) AÊ

V= 3487.4 (9) AÊ3

Z= 8

Dx= 1.330 Mg mÿ3

MoKradiation Cell parameters from 25

re¯ections

= 2±12 = 0.38 mmÿ1

T= 293 (2) K Plate, colourless 0.200.150.10 mm

Data collection

Enraf±Nonius CAD-4 diffractometer

!±2scans

Absorption correction: scan (Northet al., 1968)

Tmin= 0.934,Tmax= 0.963

3164 measured re¯ections 3163 independent re¯ections 2205 re¯ections withI> 2(I)

Rint= 0.041

max= 25.3

h=ÿ18!0

k= 0!10

l= 0!30

3 standard re¯ections every 100 re¯ections intensity decay: none

Re®nement

Re®nement onF2

R[F2> 2(F2)] = 0.051

wR(F2) = 0.140

S= 1.10 3163 re¯ections 208 parameters

H-atom parameters constrained

w= 1/[2(F

o2) + (0.0478P)2

+ 2.3284P]

whereP= (Fo2+ 2Fc2)/3

(/)max< 0.001

max= 0.22 e AÊÿ3

min=ÿ0.34 e AÊÿ3

Table 1

Selected geometric parameters (AÊ,).

O1ÐC6 1.421 (3) O1ÐC2 1.431 (3) O8ÐC4 1.207 (3) C2ÐC3 1.537 (4) C3ÐC4 1.512 (4)

C3ÐC7 1.518 (4) C4ÐC5 1.511 (4) C5ÐC9 1.523 (4) C5ÐC6 1.546 (4) C6ÐO1ÐC2 113.28 (19)

O1ÐC2ÐC3 111.3 (2) C4ÐC3ÐC2 110.3 (2)

C5ÐC4ÐC3 114.7 (2) C4ÐC5ÐC6 107.7 (2) O1ÐC6ÐC5 109.6 (2) C6ÐO1ÐC2ÐC3 ÿ59.8 (3)

O1ÐC2ÐC3ÐC4 49.2 (3) C2ÐC3ÐC4ÐC5 ÿ48.0 (3)

C3ÐC4ÐC5ÐC6 51.8 (3) C2ÐO1ÐC6ÐC5 64.5 (3) C4ÐC5ÐC6ÐO1 ÿ57.9 (3)

The H atoms were included in calculated positions. The displace-ment parameters of the methyl H atoms were ®xed as 1.5Ueqof the respective C atoms. The displacement parameters of all the other H atoms were ®xed as 1.2Ueqof the carrier atoms during re®nement.

Data collection: CAD-4 Software (Enraf±Nonius, 1989); cell re®nement: CAD-4 Software; data reduction: MolEN (Fair, 1990); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to re®ne structure:SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and

PLATON (Spek, 1997); software used to prepare material for publication:SHELXL97 andPARST(Nardelli, 1983).

Figure 2

A view of the crystal packing, showing the zigzag layer formation.

Figure 1

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References

Altomare, A., Cascarano, G., Giacovazzo, C. & Guagliardi, A. (1993).J. Appl. Cryst.26, 343±350.

Baliah, V. & Mangalam, G. (1978).Indian J. Chem. B,16, 213±215. Eliel, E. L. (1962).Stereochemistry of Carbon Compounds, p. 28. New Delhi:

McGraw-Hill.

Enraf±Nonius (1989).CAD-4Software. Version 5.0. Enraf±Nonius, Delft, The Netherlands.

Fair, C. K. (1990).MolEN.Enraf±Nonius, Delft, The Netherlands. Farrugia, L. J. (1997).J. Appl. Cryst.30, 565.

Jeffrey, G. A. & Saenger, W. (1991). Hydrogen Bonding in Biological Structures, pp. 18 and 21. Berlin: Springer-Verlag.

Kalsi, P. S. (1997).Stereochemistry: Conformation and Mechanism, p. 236. New Delhi: New Age International.

Nardelli, M. (1983).Comput. Chem.7, 95±98.

Krishnamoorthy, B. S., Sarangarajan, T. R., Panchanatheswaran, K., Thanikasalam, K. & Jeyaraman, R. (2003).Acta Cryst.E59, o461±o462. North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968).Acta Cryst.A24, 351±

359.

Sarangarajan, T. R., Panchanatheswaran, K., Thanikachalam, K. & Jeyaraman, R. (2002).Acta Cryst.E58, o1053±o1054.

Sheldrick, G. M. (1997).SHELXL97. University of GoÈttingen, Germany. Spek. A. L. (1997).PLATON97. University of Utrecht. The Netherlands.

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supporting information

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Acta Cryst. (2003). E59, o463–o465

supporting information

Acta Cryst. (2003). E59, o463–o465 [doi:10.1107/S1600536803005361]

r

-2,

c

-6-Bis(4-chlorophenyl)-

t

-3,

t

-5-dimethyltetrahydropyran-4-one

Savaridasson Jose Kavitha, Thanjavur Ramabhadran Sarangarajan, Kanagasabapathy

Thanikasalam, Krishnaswamy Panchanatheswaran and Ramasubbu Jeyaraman

S1. Comment

The title molecule, (I), contains two pairs of chiral C atoms with identical groups on each. There can be as many as four

racemic modifications and two meso forms for the molecule (Eliel, 1962). This investigation was undertaken to assign the

configuration and conformation of the most stable form in the solid state.

The saturated pyran ring adopts a distorted chair conformation, as shown by the torsion angles around the bonds

involving the ring atoms. These torsion angles deviate from the ideal value of 56° reported for the chair conformation of

cyclohexane (Kalsi, 1997). The C—C bond lengths of the phenyl rings are in the range 1.362 (4)–1.391 (4) Å, while the

bond angles are in the range 118.3 (3)–121.4 (4)°. The configurations of the chiral atoms C2, C3, C5 and C6 are found to

be R, S, R and S, respectively. The equatorial dispositions of the methyl and 4-chlorophenyl groups are revealed by the

torsion angles comprising the external atom and the other three ring atoms, which vary from −167.9 (2) to 178.3 (2)°, as

observed in a pentasubstituted cyclohexan-1-one derivative (Sarangarajan et al., 2002).

In the crystal structure, the molecules are aggregated into zigzag layers extended over the ac plane. Within the layer, a

Cl···Cl short contact of 3.406 (2) Å is observed between atoms Cl1 and Cl2i [symmetry code: (i) −1/2 − x, −y, −1/2 + z].

The adjacent layers are linked through C—H···π interactions, viz. C3—H3···Cg, with H3···Cg = 2.72 Å, C3···Cg =

3.631 (3) Å and C3—H3···Cg = 154°, where Cg denotes the centroid of the C16—C21 phenyl ring of the molecule at (-x,

1/2 + y, 1/2 − z). The molecules are also held by weak interactions (Jeffrey & Senger, 1991) between C20 and O8ii

[3.373 (4) Å; symmetry code: (ii) x − 1/2, y, −z + 1/2].

The title compound is isomorphous with the analogous p-tolyl derivative, r-2,c-6-di(p

-tolyl)-t-3,t-5-dimethyltetrahydro-pyran-4-one (Krishnamoorthy et al., 2003), with very similar crystal and molecular structures. The torsion angles around

the C—C bonds of the tetrahydropyran ring are not statistically different in the two structures. This reveals no

conformational changes due to the replacement of methyl by Cl atoms in the title molecule. The gas-phase conformation

obtained through AM1 calculations is very similar to that observed in the solid state. The calculated heat of formation of

−48.5 kcal mol−1 for the compound reveals its inherent molecular stability.

S2. Experimental

The title compound was prepared by the condensation of pentan-3-one and 4-chlorobenzaldehyde in a 1:2 molar ratio in

methanol, as reported by Baliah & Mangalam (1978). Diffraction-quality crystals were obtained by recrystallization of

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supporting information

[image:5.610.128.480.69.317.2]

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Acta Cryst. (2003). E59, o463–o465

Figure 1

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supporting information

[image:6.610.216.394.70.515.2]

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Acta Cryst. (2003). E59, o463–o465

Figure 2

A view of the molecular packing, showing the zigzag layer formation.

r-2,c-6-di(4-chlorophenyl)-t-3,t-5-dimethyltetrahydropyran-4-one

Crystal data

C19H18Cl2O2 Mr = 349.23

Orthorhombic, Pbca Hall symbol: -P 2ac 2ab a = 15.013 (1) Å b = 9.1230 (16) Å c = 25.462 (4) Å V = 3487.4 (9) Å3 Z = 8

F(000) = 1456

Dx = 1.330 Mg m−3

Melting point: 463-464 K K Mo radiation, λ = 0.71069 Å Cell parameters from 25 reflections θ = 2–12°

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Acta Cryst. (2003). E59, o463–o465

Data collection

Enraf-Nonius CAD-4 diffractometer

Radiation source: fine-focus sealed tube Graphite monochromator

ω–2θ scans

Absorption correction: ψ scan (North et al., 1968)

Tmin = 0.934, Tmax = 0.963 3164 measured reflections

3163 independent reflections 2205 reflections with I > 2σ(I) Rint = 0.041

θmax = 25.3°, θmin = 1.6° h = −18→0

k = 0→10 l = 0→30

3 standard reflections every 100 reflections intensity decay: none

Refinement

Refinement on F2 Least-squares matrix: full R[F2 > 2σ(F2)] = 0.051 wR(F2) = 0.140 S = 1.10 3163 reflections 208 parameters 0 restraints

Primary atom site location: structure-invariant direct methods

Secondary atom site location: difference Fourier map

Hydrogen site location: inferred from neighbouring sites

H-atom parameters constrained w = 1/[σ2(F

o2) + (0.0478P)2 + 2.3284P] where P = (Fo2 + 2Fc2)/3

(Δ/σ)max < 0.001 Δρmax = 0.22 e Å−3 Δρmin = −0.34 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 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. The hydrogen atoms were included in the calculated positions. The thermal parameters of all the H atoms were fixed as 1.2 times of the Ueq of their carrier atoms, except those of the methyl groups. The thermal parameters of the H atoms were fixed as 1.5 times of the Ueq of the respective carbon atoms.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

x y z Uiso*/Ueq

Cl1 −0.23836 (7) 0.02833 (16) 0.01666 (4) 0.0972 (4) Cl2 −0.08127 (7) 0.15480 (12) 0.46889 (3) 0.0824 (3) O1 0.02534 (12) 0.1605 (2) 0.21639 (7) 0.0458 (5) O8 0.24462 (15) 0.3915 (3) 0.18791 (9) 0.0769 (7) C2 0.06250 (18) 0.1593 (3) 0.16462 (10) 0.0443 (7)

H2 0.1069 0.0808 0.1622 0.053*

C3 0.10719 (19) 0.3064 (3) 0.15152 (11) 0.0503 (7)

H3 0.0599 0.3802 0.1494 0.060*

C4 0.16895 (19) 0.3520 (4) 0.19549 (11) 0.0512 (7) C5 0.12892 (19) 0.3420 (3) 0.24983 (11) 0.0473 (7)

H5 0.0795 0.4120 0.2516 0.057*

C6 0.08960 (18) 0.1865 (3) 0.25631 (10) 0.0437 (6)

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Acta Cryst. (2003). E59, o463–o465

C7 0.1531 (2) 0.3028 (5) 0.09841 (12) 0.0757 (11)

H7A 0.1804 0.3961 0.0917 0.114*

H7B 0.1100 0.2823 0.0715 0.114*

H7C 0.1979 0.2277 0.0984 0.114*

C9 0.1958 (2) 0.3839 (5) 0.29223 (13) 0.0718 (10)

H9A 0.2177 0.4811 0.2857 0.108*

H9B 0.2446 0.3160 0.2918 0.108*

H9C 0.1673 0.3811 0.3260 0.108*

C10 −0.01328 (19) 0.1260 (3) 0.12766 (10) 0.0466 (7) C11 −0.0038 (2) 0.0220 (4) 0.08873 (11) 0.0569 (8)

H11 0.0498 −0.0283 0.0853 0.068*

C12 −0.0732 (2) −0.0083 (4) 0.05471 (12) 0.0654 (9)

H12 −0.0665 −0.0795 0.0289 0.079*

C13 −0.1515 (2) 0.0666 (4) 0.05918 (11) 0.0616 (9) C14 −0.1623 (2) 0.1733 (4) 0.09694 (12) 0.0625 (9)

H14 −0.2154 0.2256 0.0993 0.075*

C15 −0.09288 (19) 0.2017 (4) 0.13140 (12) 0.0538 (8)

H15 −0.0999 0.2724 0.1574 0.065*

C16 0.04384 (18) 0.1679 (3) 0.30830 (10) 0.0424 (6) C17 0.08966 (19) 0.1095 (4) 0.35091 (11) 0.0506 (7)

H17 0.1473 0.0745 0.3462 0.061*

C18 0.0508 (2) 0.1028 (4) 0.40025 (11) 0.0557 (8)

H18 0.0822 0.0648 0.4286 0.067*

C19 −0.0341 (2) 0.1526 (3) 0.40650 (11) 0.0547 (8) C20 −0.0826 (2) 0.2061 (4) 0.36463 (12) 0.0562 (8)

H20 −0.1412 0.2365 0.3692 0.067*

C21 −0.04284 (18) 0.2138 (3) 0.31581 (11) 0.0496 (7)

H21 −0.0750 0.2505 0.2875 0.060*

Atomic displacement parameters (Å2)

U11 U22 U33 U12 U13 U23

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Acta Cryst. (2003). E59, o463–o465

C15 0.0487 (16) 0.060 (2) 0.0522 (17) 0.0036 (15) 0.0000 (13) −0.0061 (15) C16 0.0445 (15) 0.0420 (16) 0.0407 (14) −0.0025 (12) −0.0015 (11) −0.0026 (12) C17 0.0483 (16) 0.0571 (19) 0.0463 (15) 0.0041 (14) −0.0033 (13) 0.0001 (14) C18 0.0640 (19) 0.059 (2) 0.0439 (16) 0.0009 (16) −0.0019 (14) 0.0039 (14) C19 0.0618 (19) 0.054 (2) 0.0484 (16) −0.0069 (16) 0.0095 (14) −0.0044 (15) C20 0.0461 (16) 0.063 (2) 0.0591 (18) 0.0013 (15) 0.0069 (14) −0.0057 (16) C21 0.0467 (15) 0.0556 (19) 0.0466 (15) 0.0041 (14) −0.0021 (13) 0.0018 (14)

Geometric parameters (Å, º)

Cl1—C13 1.731 (3) C9—H9C 0.96

Cl2—C19 1.740 (3) C10—C11 1.380 (4)

O1—C6 1.421 (3) C10—C15 1.383 (4)

O1—C2 1.431 (3) C11—C12 1.383 (4)

O8—C4 1.207 (3) C11—H11 0.93

C2—C10 1.507 (4) C12—C13 1.364 (5)

C2—C3 1.537 (4) C12—H12 0.93

C2—H2 0.98 C13—C14 1.378 (5)

C3—C4 1.512 (4) C14—C15 1.387 (4)

C3—C7 1.518 (4) C14—H14 0.93

C3—H3 0.98 C15—H15 0.93

C4—C5 1.511 (4) C16—C21 1.380 (4)

C5—C9 1.523 (4) C16—C17 1.391 (4)

C5—C6 1.546 (4) C17—C18 1.387 (4)

C5—H5 0.98 C17—H17 0.93

C6—C16 1.501 (4) C18—C19 1.362 (4)

C6—H6 0.98 C18—H18 0.93

C7—H7A 0.96 C19—C20 1.381 (4)

C7—H7B 0.96 C20—C21 1.381 (4)

C7—H7C 0.96 C20—H20 0.93

C9—H9A 0.96 C21—H21 0.93

C9—H9B 0.96

C6—O1—C2 113.28 (19) H9A—C9—H9C 109.5

O1—C2—C10 106.4 (2) H9B—C9—H9C 109.5

O1—C2—C3 111.3 (2) C11—C10—C15 118.8 (3)

C10—C2—C3 111.7 (2) C11—C10—C2 120.6 (3)

O1—C2—H2 109.1 C15—C10—C2 120.6 (3)

C10—C2—H2 109.1 C10—C11—C12 120.6 (3)

C3—C2—H2 109.1 C10—C11—H11 119.7

C4—C3—C7 112.8 (2) C12—C11—H11 119.7

C4—C3—C2 110.3 (2) C13—C12—C11 119.8 (3)

C7—C3—C2 111.9 (3) C13—C12—H12 120.1

C4—C3—H3 107.2 C11—C12—H12 120.1

C7—C3—H3 107.2 C12—C13—C14 120.9 (3)

C2—C3—H3 107.2 C12—C13—Cl1 119.7 (3)

O8—C4—C5 122.6 (3) C14—C13—Cl1 119.4 (3)

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Acta Cryst. (2003). E59, o463–o465

C5—C4—C3 114.7 (2) C13—C14—H14 120.5

C4—C5—C9 111.8 (2) C15—C14—H14 120.5

C4—C5—C6 107.7 (2) C10—C15—C14 120.9 (3)

C9—C5—C6 114.0 (3) C10—C15—H15 119.6

C4—C5—H5 107.7 C14—C15—H15 119.6

C9—C5—H5 107.7 C21—C16—C17 118.3 (3)

C6—C5—H5 107.7 C21—C16—C6 121.3 (2)

O1—C6—C16 107.5 (2) C17—C16—C6 120.3 (2)

O1—C6—C5 109.6 (2) C18—C17—C16 121.0 (3)

C16—C6—C5 111.9 (2) C18—C17—H17 119.5

O1—C6—H6 109.2 C16—C17—H17 119.5

C16—C6—H6 109.2 C19—C18—C17 119.0 (3)

C5—C6—H6 109.2 C19—C18—H18 120.5

C3—C7—H7A 109.5 C17—C18—H18 120.5

C3—C7—H7B 109.5 C18—C19—C20 121.4 (3)

H7A—C7—H7B 109.5 C18—C19—Cl2 119.5 (2)

C3—C7—H7C 109.5 C20—C19—Cl2 119.1 (2)

H7A—C7—H7C 109.5 C21—C20—C19 119.0 (3)

H7B—C7—H7C 109.5 C21—C20—H20 120.5

C5—C9—H9A 109.5 C19—C20—H20 120.5

C5—C9—H9B 109.5 C16—C21—C20 121.1 (3)

H9A—C9—H9B 109.5 C16—C21—H21 119.4

C5—C9—H9C 109.5 C20—C21—H21 119.4

Figure

Figure 1
Figure 2

References

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