Absolute configuration of (1S,3R,8R)-10-bromo­methyl-2,2-di­chloro-3,7,7-tri­methyl­tri­cyclo­[6.4.0.01,3]dodec-9-ene

Bimoussa, A.; Auhmani, A.; Ait Itto, M.Y.; Daran, J.-C.; Auhmani, A.

doi:10.1107/S1600536813028183

organic compounds

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ISSN: 2056-9890

Volume 69| Part 11| November 2013| Pages o1692-o1693

doi:10.1107/S1600536813028183

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Absolute configuration of (1S,3R,8R)-10-bromomethyl-2,2-dichloro-3,7,7-trimethyltricyclo[6.4.0.0^1,3]dodec-9-ene

Abdoullah Bimoussa,^a Aziz Auhmani,^a My Youssef Ait Itto,^a ^* Jean-Claude Daran ^b and Abdelwahed Auhmani ^a

^aLaboratoire de Physico-Chimie Moléculaire et Synthése Organique, Département de Chimie Faculté des Sciences, Semlalia BP 2390, Marrakech 40001, Morocco, and ^bLaboratoire de Chimie de Coordination, 205 route de Narbonne, 31077 Toulouse Cedex 04, France
^*Correspondence e-mail: itto35@hotmail.com

(Received 24 September 2013; accepted 14 October 2013; online 23 October 2013)

The absolute configuration of the title compound, C₁₆H₂₃BrCl₂, has been deduced from the chemical pathway and fully confirmed by refinement of the Flack and Hooft parameters. The six-membered ring adopts a half-chair conformation, whereas the seven-membered ring is a twisted chair. The molecular packing within the crystal is stabilized only by van der Waals interactions.

CCDC reference: 966334

Related literature

For the synthesis of the title compound, see: El Jamili et al. (2002 ). For further synthetic details, see: Qu et al. (2009 ). For biological properties of cyclopropane-containing products, see: Ajay Kumar et al. (2012 ); Sow et al. (2007 ); Symon et al. (2005 ). For related structures, see: Benharref et al. (2010 ); Gassman & Gorman (1990 ); Lassaba et al. (1997 ). For conformations of rings, see: Cremer & Pople (1975 ); Boessenkool & Boyens (1980 ); For absolute structure, see: Flack (1983 ); Flack & Bernardinelli (2000 ); Spek (2009 ).

Experimental

Crystal data

C₁₆H₂₃BrCl₂
M_r = 366.15
Orthorhombic, P 2₁ 2₁ 2₁
a = 9.1000 (2) Å
b = 12.5490 (4) Å
c = 14.4070 (5) Å
V = 1645.22 (9) Å³
Z = 4
Cu Kα radiation
μ = 6.26 mm⁻¹
T = 173 K
0.45 × 0.25 × 0.10 mm

Data collection

Agilent Xcalibur Gemini ultra diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012 ) T_min = 0.397, T_max = 1.000
9248 measured reflections
3127 independent reflections
3012 reflections with I > 2σ(I)
R_int = 0.038

Refinement

R[F² > 2σ(F²)] = 0.027
wR(F²) = 0.070
S = 1.04
3127 reflections
176 parameters
H-atom parameters constrained
Δρ_max = 0.41 e Å⁻³
Δρ_min = −0.46 e Å⁻³
Absolute structure: Flack (1983), 1307 Friedel pairs
Absolute structure parameter: −0.015 (17)

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR97 (Altomare et al., 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ); software used to prepare material for publication: SHELXL97.

Supporting information

CCDC reference: 966334

Crystal structure: contains datablocks I, New_Global_Publ_Block. DOI: 10.1107/S1600536813028183/yk2099sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813028183/yk2099Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813028183/yk2099Isup3.cml

checkCIF report

Comment top

Cyclopropane-containing natural products attract great interest because of their biological properties ranging from insecticidal (Sow et al., 2007) and antimicrobial (Ajay Kumar et al., 2012) to antitumoral activities (Symon et al., 2005). They are also valuable intermediates and are frequently used as versatile building blocks in organic synthesis (Qu et al., 2009).

In our ongoing studies on the synthesis of new chiral sesquiterpenic cyclopropanes, we carried out the reaction of (1S,3R,8R)-2,2-dichloro-3,7,7-10-tetramethyltricyclo[6.4.0.0^1,3]dodec-9-ene (El Jamili et al., 2002) with N-bromosuccinimide (NBS) and obtained the title compound in poor yield. Its gross structure was confirmed by spectroscopic data, and its stereochemistry was fully established as (1S,3R,8R) to prove no racemization during the reaction process.

A view of the molecule is represented in Fig. 1. As observed in related compounds (Gassman & Gorman, 1990; Lassaba et al., 1997; Benharref et al., 2010), each molecule is built up from two fused six-and seven-membered rings. The six-membered ring has roughly half-chair conformation with the puckering parameters: Q = 0.493 (3) Å, spherical polar angle θ= 131.2 (3)° and ϕ= 147.2 (4)° (Cremer & Pople, 1975), whereas the seven-membered ring displays a twisted chair conformation with a total puckering amplitude of 1.148 (3) Å. (Boessenkool & Boyens, 1980).

The absolute configuration (1S,3R,8R) deduced from the chemical pathway is confirmed by the refinement of the Flack's parameter, -0.015 (17), (Flack, 1983; Flack & Bernardinelli, 2000) and by the refinement of the Hooft's parameter, -0.021 (11) (Spek, 2009).

The packing of the molecules within the crystal is only stabilized by van der Waals interactions.

Related literature top

For the synthesis of the title compound, see: El Jamili et al. (2002). For further synthetic details, see: Qu et al. (2009). For biological properties of cyclopropane-containing products, see: Ajay Kumar et al. (2012); Sow et al. (2007); Symon et al. (2005). For related structures, see: Benharref et al. (2010); Gassman & Gorman (1990); Lassaba et al. (1997). For conformations of rings, see: Cremer & Pople (1975); Boessenkool & Boyens (1980); For absolute structure, see: Flack (1983); Flack & Bernardinelli (2000); Spek (2009).

Experimental top

To a cooled (0°C) solution of (1S,3R,8R)-2,2-dichloro-\3,7,7-10-tetramethyltricyclo[6.4.0.0^1,3]dodec-9-ene (4,6 mmol) in 50 ml of a solvent mixture THF/H₂O (4/1, v/v), NBS (9,16 mmol) was added in small portions, then mixture was kept under stirring at 0°C for two hours. After completion of the reaction, 15% sodium hydrogenocarbonate solution was added and the reaction mixture was taken up in ether, dried over anhydrous sodium sulfate, and concentrated. The crude product was purified by chromatography on silica gel (230–400 mesh) with hexane as eluent to give the title compound in 9% yield.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis PRO (Agilent, 2012); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. The asymmetric unit of (I) with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented as small spheres of arbitrary radii.

(1S,3R,8R)-10-Bromomethyl-2,2-dichloro-3,7,7-trimethyltricyclo[6.4.0.0^1,3]dodec-9-ene top

Crystal data top

C₁₆H₂₃BrCl₂	F(000) = 752
M_r = 366.15	D_x = 1.478 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Cu Kα radiation, λ = 1.54184 Å
Hall symbol: P 2ac 2ab	Cell parameters from 5474 reflections
a = 9.1000 (2) Å	θ = 3.1–70.8°
b = 12.5490 (4) Å	µ = 6.26 mm⁻¹
c = 14.4070 (5) Å	T = 173 K
V = 1645.22 (9) Å³	Box, colourless
Z = 4	0.45 × 0.25 × 0.10 mm

Data collection top

Agilent Xcalibur Gemini ultra diffractometer	3127 independent reflections
Radiation source: Enhance Ultra (Cu) X-ray Source	3012 reflections with I > 2σ(I)
Mirror monochromator	R_int = 0.038
Detector resolution: 16.1978 pixels mm^-1	θ_max = 70.9°, θ_min = 4.7°
ω scans	h = −11→11
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012)	k = −15→14
T_min = 0.397, T_max = 1.000	l = −17→17
9248 measured reflections

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.027	w = 1/[σ²(F_o²) + (0.0372P)² + 0.318P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.070	(Δ/σ)_max < 0.001
S = 1.04	Δρ_max = 0.41 e Å⁻³
3127 reflections	Δρ_min = −0.46 e Å⁻³
176 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0037 (2)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 1307 Friedel pairs
Secondary atom site location: difference Fourier map	Absolute structure parameter: −0.015 (17)

Crystal data top

C₁₆H₂₃BrCl₂	V = 1645.22 (9) Å³
M_r = 366.15	Z = 4
Orthorhombic, P2₁2₁2₁	Cu Kα radiation
a = 9.1000 (2) Å	µ = 6.26 mm⁻¹
b = 12.5490 (4) Å	T = 173 K
c = 14.4070 (5) Å	0.45 × 0.25 × 0.10 mm

Data collection top

Agilent Xcalibur Gemini ultra diffractometer	3127 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012)	3012 reflections with I > 2σ(I)
T_min = 0.397, T_max = 1.000	R_int = 0.038
9248 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.027	H-atom parameters constrained
wR(F²) = 0.070	Δρ_max = 0.41 e Å⁻³
S = 1.04	Δρ_min = −0.46 e Å⁻³
3127 reflections	Absolute structure: Flack (1983), 1307 Friedel pairs
176 parameters	Absolute structure parameter: −0.015 (17)
0 restraints

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 > 2σ(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

	x	y	z	U_iso*/U_eq
C1	0.3341 (3)	0.3344 (2)	0.29478 (17)	0.0200 (5)
C2	0.4125 (3)	0.2394 (2)	0.33667 (17)	0.0245 (5)
C3	0.3927 (3)	0.3389 (2)	0.39476 (17)	0.0264 (5)
C4	0.2786 (4)	0.3369 (2)	0.47129 (18)	0.0356 (6)
H4A	0.3274	0.3208	0.5311	0.043*
H4B	0.2068	0.2795	0.4586	0.043*
C5	0.1975 (4)	0.4434 (2)	0.47910 (19)	0.0372 (6)
H5A	0.2572	0.4925	0.5175	0.045*
H5B	0.1035	0.4314	0.5120	0.045*
C6	0.1646 (3)	0.4980 (2)	0.38583 (18)	0.0312 (6)
H6A	0.1074	0.5634	0.3989	0.037*
H6B	0.2594	0.5208	0.3586	0.037*
C7	0.0814 (3)	0.4344 (2)	0.31168 (19)	0.0295 (6)
C8	0.1674 (3)	0.3298 (2)	0.28177 (17)	0.0226 (5)
H8	0.1312	0.2714	0.3231	0.027*
C9	0.1316 (3)	0.2964 (2)	0.18373 (18)	0.0259 (5)
H9	0.0338	0.2742	0.1709	0.031*
C10	0.2264 (3)	0.2957 (2)	0.11464 (16)	0.0249 (5)
C11	0.3846 (3)	0.3268 (2)	0.12612 (16)	0.0234 (5)
H11A	0.4155	0.3702	0.0721	0.028*
H11B	0.4460	0.2617	0.1273	0.028*
C12	0.4109 (2)	0.39027 (19)	0.21497 (16)	0.0222 (5)
H12A	0.5176	0.3952	0.2276	0.027*
H12B	0.3717	0.4634	0.2079	0.027*
C13	0.5259 (3)	0.4058 (2)	0.4181 (2)	0.0378 (7)
H13A	0.4943	0.4778	0.4355	0.057*
H13B	0.5907	0.4097	0.3639	0.057*
H13C	0.5789	0.3733	0.4701	0.057*
C14	−0.0692 (3)	0.4003 (3)	0.3467 (3)	0.0564 (10)
H14A	−0.0577	0.3582	0.4036	0.085*
H14B	−0.1181	0.3570	0.2993	0.085*
H14C	−0.1286	0.4636	0.3599	0.085*
C15	0.0576 (4)	0.5105 (2)	0.2286 (2)	0.0399 (7)
H15A	0.0002	0.4742	0.1806	0.060*
H15B	0.1530	0.5317	0.2031	0.060*
H15C	0.0044	0.5741	0.2496	0.060*
C16	0.1748 (3)	0.2646 (2)	0.01985 (19)	0.0339 (6)
H16A	0.1982	0.3225	−0.0244	0.041*
H16B	0.0667	0.2556	0.0208	0.041*
Cl1	0.59023 (7)	0.20569 (6)	0.29648 (5)	0.03423 (16)
Cl2	0.31861 (8)	0.12015 (5)	0.36321 (5)	0.03703 (17)
Br1	0.26676 (3)	0.13107 (2)	−0.02346 (2)	0.04148 (11)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0227 (10)	0.0175 (11)	0.0199 (11)	0.0007 (9)	0.0004 (10)	−0.0003 (9)
C2	0.0243 (11)	0.0226 (12)	0.0266 (12)	0.0009 (10)	−0.0006 (10)	0.0019 (10)
C3	0.0342 (13)	0.0217 (12)	0.0232 (12)	0.0033 (11)	−0.0033 (10)	−0.0004 (9)
C4	0.0548 (16)	0.0300 (14)	0.0219 (11)	0.0021 (13)	0.0046 (14)	0.0007 (10)
C5	0.0516 (16)	0.0350 (15)	0.0249 (12)	0.0037 (13)	0.0037 (13)	−0.0042 (11)
C6	0.0341 (14)	0.0269 (14)	0.0327 (14)	0.0029 (12)	0.0033 (12)	−0.0063 (11)
C7	0.0223 (12)	0.0320 (14)	0.0342 (14)	0.0048 (11)	0.0042 (11)	−0.0070 (11)
C8	0.0197 (10)	0.0210 (13)	0.0272 (13)	−0.0046 (9)	0.0033 (10)	−0.0029 (9)
C9	0.0187 (11)	0.0244 (12)	0.0347 (14)	0.0017 (10)	−0.0040 (10)	−0.0052 (11)
C10	0.0284 (13)	0.0217 (11)	0.0247 (11)	0.0060 (11)	−0.0064 (10)	−0.0023 (9)
C11	0.0251 (12)	0.0246 (13)	0.0203 (11)	0.0018 (10)	0.0036 (9)	0.0019 (9)
C12	0.0178 (10)	0.0208 (12)	0.0280 (12)	−0.0003 (10)	0.0006 (9)	0.0014 (10)
C13	0.0402 (16)	0.0347 (16)	0.0383 (16)	0.0004 (13)	−0.0167 (13)	−0.0079 (12)
C14	0.0283 (15)	0.057 (2)	0.084 (3)	−0.0018 (15)	0.0225 (17)	−0.021 (2)
C15	0.0409 (15)	0.0380 (17)	0.0408 (16)	0.0156 (14)	−0.0075 (13)	−0.0083 (13)
C16	0.0414 (14)	0.0292 (14)	0.0313 (13)	0.0103 (12)	−0.0075 (13)	−0.0094 (12)
Cl1	0.0269 (3)	0.0328 (4)	0.0430 (4)	0.0090 (3)	−0.0042 (3)	−0.0005 (3)
Cl2	0.0493 (4)	0.0205 (3)	0.0413 (3)	−0.0027 (3)	0.0060 (3)	0.0046 (3)
Br1	0.03964 (16)	0.03661 (18)	0.04820 (18)	0.00297 (14)	−0.00203 (13)	−0.01953 (14)

Geometric parameters (Å, º) top

C1—C2	1.515 (3)	C8—H8	1.0000
C1—C12	1.518 (3)	C9—C10	1.317 (4)
C1—C8	1.529 (3)	C9—H9	0.9500
C1—C3	1.537 (3)	C10—C16	1.496 (3)
C2—C3	1.515 (3)	C10—C11	1.501 (3)
C2—Cl2	1.765 (3)	C11—C12	1.526 (3)
C2—Cl1	1.769 (3)	C11—H11A	0.9900
C3—C13	1.512 (4)	C11—H11B	0.9900
C3—C4	1.515 (4)	C12—H12A	0.9900
C4—C5	1.531 (4)	C12—H12B	0.9900
C4—H4A	0.9900	C13—H13A	0.9800
C4—H4B	0.9900	C13—H13B	0.9800
C5—C6	1.538 (4)	C13—H13C	0.9800
C5—H5A	0.9900	C14—H14A	0.9800
C5—H5B	0.9900	C14—H14B	0.9800
C6—C7	1.533 (4)	C14—H14C	0.9800
C6—H6A	0.9900	C15—H15A	0.9800
C6—H6B	0.9900	C15—H15B	0.9800
C7—C14	1.522 (4)	C15—H15C	0.9800
C7—C15	1.546 (4)	C16—Br1	1.974 (3)
C7—C8	1.589 (4)	C16—H16A	0.9900
C8—C9	1.509 (3)	C16—H16B	0.9900

C2—C1—C12	116.7 (2)	C9—C8—H8	106.4
C2—C1—C8	119.1 (2)	C1—C8—H8	106.4
C12—C1—C8	112.4 (2)	C7—C8—H8	106.4
C2—C1—C3	59.50 (16)	C10—C9—C8	124.6 (2)
C12—C1—C3	122.2 (2)	C10—C9—H9	117.7
C8—C1—C3	117.4 (2)	C8—C9—H9	117.7
C3—C2—C1	60.98 (16)	C9—C10—C16	119.1 (2)
C3—C2—Cl2	121.47 (19)	C9—C10—C11	122.9 (2)
C1—C2—Cl2	121.68 (18)	C16—C10—C11	118.0 (2)
C3—C2—Cl1	119.12 (19)	C10—C11—C12	112.2 (2)
C1—C2—Cl1	119.24 (18)	C10—C11—H11A	109.2
Cl2—C2—Cl1	108.12 (14)	C12—C11—H11A	109.2
C13—C3—C4	113.4 (2)	C10—C11—H11B	109.2
C13—C3—C2	119.0 (2)	C12—C11—H11B	109.2
C4—C3—C2	118.0 (2)	H11A—C11—H11B	107.9
C13—C3—C1	120.5 (2)	C1—C12—C11	108.8 (2)
C4—C3—C1	116.3 (2)	C1—C12—H12A	109.9
C2—C3—C1	59.51 (16)	C11—C12—H12A	109.9
C3—C4—C5	111.7 (2)	C1—C12—H12B	109.9
C3—C4—H4A	109.3	C11—C12—H12B	109.9
C5—C4—H4A	109.3	H12A—C12—H12B	108.3
C3—C4—H4B	109.3	C3—C13—H13A	109.5
C5—C4—H4B	109.3	C3—C13—H13B	109.5
H4A—C4—H4B	107.9	H13A—C13—H13B	109.5
C4—C5—C6	114.7 (2)	C3—C13—H13C	109.5
C4—C5—H5A	108.6	H13A—C13—H13C	109.5
C6—C5—H5A	108.6	H13B—C13—H13C	109.5
C4—C5—H5B	108.6	C7—C14—H14A	109.5
C6—C5—H5B	108.6	C7—C14—H14B	109.5
H5A—C5—H5B	107.6	H14A—C14—H14B	109.5
C7—C6—C5	118.3 (2)	C7—C14—H14C	109.5
C7—C6—H6A	107.7	H14A—C14—H14C	109.5
C5—C6—H6A	107.7	H14B—C14—H14C	109.5
C7—C6—H6B	107.7	C7—C15—H15A	109.5
C5—C6—H6B	107.7	C7—C15—H15B	109.5
H6A—C6—H6B	107.1	H15A—C15—H15B	109.5
C14—C7—C6	111.1 (2)	C7—C15—H15C	109.5
C14—C7—C15	107.7 (3)	H15A—C15—H15C	109.5
C6—C7—C15	106.7 (2)	H15B—C15—H15C	109.5
C14—C7—C8	107.5 (2)	C10—C16—Br1	112.15 (18)
C6—C7—C8	112.1 (2)	C10—C16—H16A	109.2
C15—C7—C8	111.7 (2)	Br1—C16—H16A	109.2
C9—C8—C1	109.8 (2)	C10—C16—H16B	109.2
C9—C8—C7	112.2 (2)	Br1—C16—H16B	109.2
C1—C8—C7	115.1 (2)	H16A—C16—H16B	107.9

Experimental details

Crystal data
Chemical formula	C₁₆H₂₃BrCl₂
M_r	366.15
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	173
a, b, c (Å)	9.1000 (2), 12.5490 (4), 14.4070 (5)
V (Å³)	1645.22 (9)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	6.26
Crystal size (mm)	0.45 × 0.25 × 0.10

Data collection
Diffractometer	Agilent Xcalibur Gemini ultra diffractometer
Absorption correction	Multi-scan (CrysAlis PRO; Agilent, 2012)
T_min, T_max	0.397, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	9248, 3127, 3012
R_int	0.038
(sin θ/λ)_max (Å⁻¹)	0.613

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.027, 0.070, 1.04
No. of reflections	3127
No. of parameters	176
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.41, −0.46
Absolute structure	Flack (1983), 1307 Friedel pairs
Absolute structure parameter	−0.015 (17)

Computer programs: CrysAlis PRO (Agilent, 2012), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 2012).

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