(1S,2S,6S,9S)-6-Methyl-5-oxobicyclo­[4.4.0]decane-2,9-diyl diacetate

Aav, R.; Lippur, K.; Lopp, M.; Werner, F.

doi:10.1107/S1600536810036639

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 66| Part 10| October 2010| Page o2584

doi:10.1107/S1600536810036639

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(1S,2S,6S,9S)-6-Methyl-5-oxobicyclo[4.4.0]decane-2,9-diyl diacetate

Riina Aav,^a Kristin Lippur,^a Margus Lopp ^a and Franz Werner ^a ^*

^aTallinn University of Technology, Department of Chemistry, Akadeemia tee 15, 12618 Tallinn, Estonia
^*Correspondence e-mail: fwerner@chemnet.ee

(Received 9 September 2010; accepted 13 September 2010; online 18 September 2010)

The chiral title compound, C₁₅H₂₂O₅, is an intermediate in the total synthesis of biologically active 9,11-secosterols. In the crystal, the cyclohexane rings are trans-fused and both adopt chair conformations. In the crystal, molecules are loosely held together in a layer parallel to (100) by weak intermolcular C—H⋯O hydrogen bonds accepted by carbonyl O atoms of the acetyl groups.

Related literature

For background to the biological activity of 9,11-secosterols and the synthesis of the title compound, see: Aav et al. (2000 ). For a related structure, see: Foot et al. (2006 ). For hydrogen bonding, see: Steiner (2002 ).

Experimental

Crystal data

C₁₅H₂₂O₅
M_r = 282.33
Monoclinic, C 2
a = 22.885 (5) Å
b = 9.340 (2) Å
c = 7.2250 (13) Å
β = 101.280 (6)°
V = 1514.5 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 300 K
0.50 × 0.20 × 0.16 mm

Data collection

Bruker SMART X2S benchtop diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2008b ) T_min = 0.955, T_max = 0.985
4796 measured reflections
1413 independent reflections
1226 reflections with I > 2σ(I)
R_int = 0.041

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.099
S = 1.05
1413 reflections
185 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.15 e Å⁻³
Δρ_min = −0.14 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C8—H8B⋯O3ⁱ	0.97	2.62	3.551 (4)	161
C13—H13C⋯O3ⁱⁱ	0.96	2.63	3.533 (4)	156
C8—H8A⋯O5ⁱⁱⁱ	0.97	2.44	3.309 (4)	149
C11—H11A⋯O5ⁱⁱⁱ	0.96	2.70	3.662 (4)	178
Symmetry codes: (i) x, y, z+1; (ii) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z]$ ; (iii) x, y+1, z.

Data collection: GIS (Bruker, 2010 ); cell refinement: APEX2 (Bruker, 2010) and SAINT (Bruker, 2009 ); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008a ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008a); molecular graphics: Mercury (Macrae et al., 2006 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810036639/is2600sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810036639/is2600Isup2.hkl

checkCIF report

Comment top

At 300 K the enantiopure compound (1S,2S,6S,9S)-6-Methyl-5-oxobicyclo[4.4.0]decane-2,9-diyl diacetate, (I), crystallizes in the chirodescriptive monoclinic space group C2 (No. 5) with one molecule in the asymmetric unit. Bond lengths and bond angles in the molecule are normal. The trans-fused cyclohexane rings both adopt chair conformation. The acetyl groups are inclined to the least-squares plane, defined by the carbon atoms of the cyclohexane rings, by ~46.4 (O2O3C12C13) and ~51.2° (O4O5C14C15), respectively (Fig. 1). The molecules are loosely hold together in layers parallel to the A-plane with a repeating distance of d₁₀₀/2~11.2 Å, within which weak intra- and intermolecular hydrogen bonds (Steiner, 2002) occur (Fig, 2, Table 1). Between the layers only hydrophobic interactions are present.

Related literature top

For background [to what?] and the synthesis of the title compound, see: Aav et al. (2000). For a related structure, see: Foot et al. (2006). For hydrogen bonding, see: Steiner (2002).

Experimental top

Enantiopure (I) was synthesized according to Aav et al. (2000). Single crystals were grown by slow evaporation of a solution of (I) in acetone/petrol ether.

Computing details top

Data collection: GIS (Bruker, 2010); cell refinement: APEX2 (Bruker, 2010) and SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008a); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008a); molecular graphics: Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008a).

Figures top

	Fig. 1. Asymmetric unit in the crystal structure of (I). Displacement ellipsoids for non-H atoms are drawn at the 50% probability level. Cyan dashed lines indicate weak hydrogen bonds. [Symmetry codes: (i) x, y, 1 + z; (ii) x, 1 + y, z; (iii) 1/2 - x, 1/2 + y, -z; (iv) x, y, -1 + z; (v) 1/2 - x, -1/2 + y, -z; (vi) x, -1 + y, z.]
	Fig. 2. Packing diagram of (I). Red planes indicate the boundaries of the layers within which weak hydrogen bonds occur. The unit cell is outlined.

(1S,2S,6S,9S)-6-Methyl-5-oxobicyclo[4.4.0]decane-2,9-diyl diacetate top

Crystal data top

C₁₅H₂₂O₅	F(000) = 608
M_r = 282.33	D_x = 1.238 Mg m⁻³
Monoclinic, C2	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C 2y	Cell parameters from 2044 reflections
a = 22.885 (5) Å	θ = 2.4–23.9°
b = 9.340 (2) Å	µ = 0.09 mm⁻¹
c = 7.2250 (13) Å	T = 300 K
β = 101.280 (6)°	Needle, colorless
V = 1514.5 (5) Å³	0.50 × 0.20 × 0.16 mm
Z = 4

Data collection top

Bruker SMART X2S benchtop diffractometer	1413 independent reflections
Radiation source: XOS X-beam microfocus source	1226 reflections with I > 2σ(I)
Doubly curved silicon crystal monochromator	R_int = 0.041
ω scans	θ_max = 25.0°, θ_min = 2.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 2008b)	h = −27→27
T_min = 0.955, T_max = 0.985	k = −11→11
4796 measured reflections	l = −7→8

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.037	H-atom parameters constrained
wR(F²) = 0.099	w = 1/[σ²(F_o²) + (0.0528P)² + 0.0812P] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max < 0.001
1413 reflections	Δρ_max = 0.15 e Å⁻³
185 parameters	Δρ_min = −0.14 e Å⁻³
1 restraint	Extinction correction: SHELXL97 (Sheldrick, 2008a), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.010 (2)

Crystal data top

C₁₅H₂₂O₅	V = 1514.5 (5) Å³
M_r = 282.33	Z = 4
Monoclinic, C2	Mo Kα radiation
a = 22.885 (5) Å	µ = 0.09 mm⁻¹
b = 9.340 (2) Å	T = 300 K
c = 7.2250 (13) Å	0.50 × 0.20 × 0.16 mm
β = 101.280 (6)°

Data collection top

Bruker SMART X2S benchtop diffractometer	1413 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2008b)	1226 reflections with I > 2σ(I)
T_min = 0.955, T_max = 0.985	R_int = 0.041
4796 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	1 restraint
wR(F²) = 0.099	H-atom parameters constrained
S = 1.05	Δρ_max = 0.15 e Å⁻³
1413 reflections	Δρ_min = −0.14 e Å⁻³
185 parameters

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

	x	y	z	U_iso*/U_eq
C1	0.41782 (12)	0.1268 (3)	0.8403 (4)	0.0548 (7)
H1A	0.4505	0.1429	0.9460	0.066*
H1B	0.3854	0.0837	0.8891	0.066*
C2	0.43814 (13)	0.0228 (3)	0.7031 (5)	0.0603 (8)
H2A	0.4735	0.0603	0.6649	0.072*
H2B	0.4484	−0.0683	0.7656	0.072*
C3	0.38967 (12)	0.0004 (3)	0.5307 (4)	0.0507 (7)
H3	0.3559	−0.0484	0.5683	0.061*
C4	0.36824 (12)	0.1415 (3)	0.4352 (4)	0.0481 (6)
H4B	0.3359	0.1237	0.3292	0.058*
H4A	0.4005	0.1868	0.3878	0.058*
C5	0.34678 (11)	0.2411 (2)	0.5769 (4)	0.0417 (6)
H5	0.3154	0.1895	0.6241	0.050*
C6	0.31877 (12)	0.3794 (3)	0.4877 (4)	0.0460 (6)
H6	0.3485	0.4372	0.4405	0.055*
C7	0.29180 (14)	0.4638 (3)	0.6307 (4)	0.0619 (8)
H7B	0.2590	0.4099	0.6630	0.074*
H7A	0.2761	0.5536	0.5745	0.074*
C8	0.33767 (15)	0.4945 (3)	0.8099 (4)	0.0625 (8)
H8A	0.3653	0.5665	0.7822	0.075*
H8B	0.3174	0.5338	0.9044	0.075*
C9	0.37226 (13)	0.3646 (3)	0.8900 (4)	0.0559 (7)
O1	0.38133 (13)	0.3386 (3)	1.0571 (3)	0.0894 (8)
C10	0.39716 (11)	0.2710 (3)	0.7505 (4)	0.0458 (6)
C11	0.45030 (12)	0.3532 (4)	0.6993 (4)	0.0619 (7)
H11A	0.4377	0.4477	0.6568	0.093*
H11B	0.4645	0.3033	0.6006	0.093*
H11C	0.4817	0.3598	0.8085	0.093*
O2	0.27152 (7)	0.33569 (19)	0.3333 (2)	0.0510 (5)
C12	0.25230 (13)	0.4324 (3)	0.1969 (4)	0.0523 (7)
O3	0.26894 (10)	0.5536 (2)	0.2034 (3)	0.0678 (6)
C13	0.20704 (15)	0.3674 (4)	0.0446 (4)	0.0689 (9)
H13A	0.1906	0.4400	−0.0446	0.103*
H13B	0.1758	0.3257	0.0982	0.103*
H13C	0.2254	0.2945	−0.0183	0.103*
O4	0.41045 (9)	−0.08472 (18)	0.3880 (3)	0.0610 (6)
C14	0.41311 (14)	−0.2269 (3)	0.4139 (5)	0.0673 (9)
O5	0.40094 (15)	−0.2845 (3)	0.5499 (5)	0.1017 (10)
C15	0.43333 (19)	−0.3023 (4)	0.2556 (6)	0.0896 (12)
H15A	0.4749	−0.3250	0.2920	0.134*
H15B	0.4272	−0.2414	0.1464	0.134*
H15C	0.4109	−0.3889	0.2263	0.134*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0477 (15)	0.0635 (17)	0.0480 (15)	−0.0007 (12)	−0.0035 (12)	0.0094 (13)
C2	0.0505 (16)	0.0594 (17)	0.0648 (19)	0.0099 (13)	−0.0041 (14)	0.0092 (14)
C3	0.0501 (15)	0.0431 (12)	0.0586 (17)	0.0034 (11)	0.0097 (13)	0.0039 (13)
C4	0.0499 (15)	0.0457 (13)	0.0460 (15)	0.0032 (11)	0.0029 (12)	0.0039 (11)
C5	0.0389 (12)	0.0430 (12)	0.0428 (14)	−0.0014 (10)	0.0071 (11)	0.0087 (11)
C6	0.0471 (13)	0.0471 (13)	0.0435 (14)	0.0033 (10)	0.0081 (12)	0.0023 (11)
C7	0.0649 (18)	0.0655 (18)	0.0561 (17)	0.0190 (14)	0.0137 (16)	0.0037 (15)
C8	0.080 (2)	0.0593 (16)	0.0500 (16)	0.0057 (15)	0.0167 (16)	−0.0031 (14)
C9	0.0597 (16)	0.0617 (17)	0.0464 (16)	−0.0076 (13)	0.0107 (13)	−0.0014 (13)
O1	0.128 (2)	0.0996 (19)	0.0414 (12)	0.0212 (18)	0.0181 (13)	0.0080 (13)
C10	0.0410 (13)	0.0527 (14)	0.0430 (14)	−0.0023 (11)	0.0067 (11)	0.0048 (11)
C11	0.0475 (14)	0.0716 (18)	0.0660 (18)	−0.0132 (14)	0.0093 (13)	−0.0024 (16)
O2	0.0517 (10)	0.0500 (10)	0.0470 (10)	0.0037 (8)	−0.0007 (8)	0.0103 (9)
C12	0.0601 (16)	0.0520 (15)	0.0464 (16)	0.0186 (13)	0.0140 (14)	0.0063 (13)
O3	0.0948 (17)	0.0498 (11)	0.0581 (13)	0.0096 (11)	0.0132 (11)	0.0094 (10)
C13	0.079 (2)	0.0689 (19)	0.0520 (17)	0.0173 (16)	−0.0041 (15)	0.0027 (15)
O4	0.0668 (13)	0.0433 (10)	0.0724 (15)	0.0070 (8)	0.0127 (11)	0.0004 (9)
C14	0.0613 (18)	0.0466 (16)	0.085 (3)	0.0011 (13)	−0.0078 (17)	0.0000 (16)
O5	0.138 (3)	0.0503 (12)	0.117 (2)	−0.0015 (14)	0.024 (2)	0.0167 (14)
C15	0.093 (3)	0.0586 (18)	0.106 (3)	0.0127 (18)	−0.007 (2)	−0.0224 (19)

Geometric parameters (Å, º) top

C1—C2	1.524 (4)	C8—H8A	0.9700
C1—C10	1.528 (4)	C8—H8B	0.9700
C1—H1A	0.9700	C9—O1	1.209 (3)
C1—H1B	0.9700	C9—C10	1.526 (4)
C2—C3	1.512 (4)	C10—C11	1.543 (4)
C2—H2A	0.9700	C11—H11A	0.9600
C2—H2B	0.9700	C11—H11B	0.9600
C3—O4	1.453 (3)	C11—H11C	0.9600
C3—C4	1.523 (4)	O2—C12	1.346 (3)
C3—H3	0.9800	C12—O3	1.193 (4)
C4—C5	1.533 (3)	C12—O3	1.193 (4)
C4—H4B	0.9700	C12—C13	1.485 (4)
C4—H4A	0.9700	C13—H13A	0.9600
C5—C6	1.527 (3)	C13—H13B	0.9600
C5—C10	1.554 (3)	C13—H13C	0.9600
C5—H5	0.9800	O4—C14	1.340 (4)
C6—O2	1.452 (3)	C14—O5	1.200 (4)
C6—C7	1.523 (4)	C14—O5	1.200 (4)
C6—H6	0.9800	C14—C15	1.492 (5)
C7—C8	1.526 (4)	C15—H15A	0.9600
C7—H7B	0.9700	C15—H15B	0.9600
C7—H7A	0.9700	C15—H15C	0.9600
C8—C9	1.502 (4)

C2—C1—C10	113.2 (2)	C7—C8—H8A	108.9
C2—C1—H1A	108.9	C9—C8—H8B	108.9
C10—C1—H1A	108.9	C7—C8—H8B	108.9
C2—C1—H1B	108.9	H8A—C8—H8B	107.7
C10—C1—H1B	108.9	O1—C9—C8	121.5 (3)
H1A—C1—H1B	107.8	O1—C9—C10	122.1 (3)
C3—C2—C1	110.9 (2)	C8—C9—C10	116.4 (2)
C3—C2—H2A	109.5	C9—C10—C1	110.4 (2)
C1—C2—H2A	109.5	C9—C10—C11	106.7 (2)
C3—C2—H2B	109.5	C1—C10—C11	110.3 (2)
C1—C2—H2B	109.5	C9—C10—C5	108.8 (2)
H2A—C2—H2B	108.1	C1—C10—C5	107.7 (2)
O4—C3—C2	111.8 (2)	C11—C10—C5	113.0 (2)
O4—C3—C4	105.9 (2)	C10—C11—H11A	109.5
C2—C3—C4	111.9 (2)	C10—C11—H11B	109.5
O4—C3—H3	109.1	H11A—C11—H11B	109.5
C2—C3—H3	109.1	C10—C11—H11C	109.5
C4—C3—H3	109.1	H11A—C11—H11C	109.5
C3—C4—C5	109.8 (2)	H11B—C11—H11C	109.5
C3—C4—H4B	109.7	C12—O2—C6	117.5 (2)
C5—C4—H4B	109.7	O3—C12—O2	123.5 (3)
C3—C4—H4A	109.7	O3—C12—O2	123.5 (3)
C5—C4—H4A	109.7	O3—C12—C13	126.0 (3)
H4B—C4—H4A	108.2	O3—C12—C13	126.0 (3)
C6—C5—C4	113.18 (19)	O2—C12—C13	110.4 (3)
C6—C5—C10	111.9 (2)	C12—C13—H13A	109.5
C4—C5—C10	111.34 (19)	C12—C13—H13B	109.5
C6—C5—H5	106.7	H13A—C13—H13B	109.5
C4—C5—H5	106.7	C12—C13—H13C	109.5
C10—C5—H5	106.7	H13A—C13—H13C	109.5
O2—C6—C7	109.1 (2)	H13B—C13—H13C	109.5
O2—C6—C5	105.94 (19)	C14—O4—C3	117.1 (3)
C7—C6—C5	110.1 (2)	O5—C14—O4	123.2 (3)
O2—C6—H6	110.5	O5—C14—O4	123.2 (3)
C7—C6—H6	110.5	O5—C14—C15	124.9 (3)
C5—C6—H6	110.5	O5—C14—C15	124.9 (3)
C6—C7—C8	111.7 (2)	O4—C14—C15	111.9 (3)
C6—C7—H7B	109.3	C14—C15—H15A	109.5
C8—C7—H7B	109.3	C14—C15—H15B	109.5
C6—C7—H7A	109.3	H15A—C15—H15B	109.5
C8—C7—H7A	109.3	C14—C15—H15C	109.5
H7B—C7—H7A	107.9	H15A—C15—H15C	109.5
C9—C8—C7	113.5 (3)	H15B—C15—H15C	109.5
C9—C8—H8A	108.9

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7A···O3	0.97	2.65	3.143 (4)	112
C8—H8B···O3ⁱ	0.97	2.62	3.551 (4)	161
C13—H13C···O3ⁱⁱ	0.96	2.63	3.533 (4)	156
C2—H2B···O5	0.97	2.65	3.134 (4)	111
C8—H8A···O5ⁱⁱⁱ	0.97	2.44	3.309 (4)	149
C11—H11A···O5ⁱⁱⁱ	0.96	2.70	3.662 (4)	178

Symmetry codes: (i) x, y, z+1; (ii) −x+1/2, y−1/2, −z; (iii) x, y+1, z.

Experimental details

Crystal data
Chemical formula	C₁₅H₂₂O₅
M_r	282.33
Crystal system, space group	Monoclinic, C2
Temperature (K)	300
a, b, c (Å)	22.885 (5), 9.340 (2), 7.2250 (13)
β (°)	101.280 (6)
V (Å³)	1514.5 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.50 × 0.20 × 0.16

Data collection
Diffractometer	Bruker SMART X2S benchtop diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2008b)
T_min, T_max	0.955, 0.985
No. of measured, independent and observed [I > 2σ(I)] reflections	4796, 1413, 1226
R_int	0.041
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.099, 1.05
No. of reflections	1413
No. of parameters	185
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.15, −0.14

Computer programs: GIS (Bruker, 2010), APEX2 (Bruker, 2010) and SAINT (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008a), SHELXL97 (Sheldrick, 2008a), Mercury (Macrae et al., 2006).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C7—H7A···O3	0.97	2.65	3.143 (4)	111.6
C8—H8B···O3ⁱ	0.97	2.62	3.551 (4)	160.9
C13—H13C···O3ⁱⁱ	0.96	2.63	3.533 (4)	156.3
C2—H2B···O5	0.97	2.65	3.134 (4)	111.2
C8—H8A···O5ⁱⁱⁱ	0.97	2.44	3.309 (4)	148.9
C11—H11A···O5ⁱⁱⁱ	0.96	2.70	3.662 (4)	177.8

Symmetry codes: (i) x, y, z+1; (ii) −x+1/2, y−1/2, −z; (iii) x, y+1, z.

Acknowledgements

The authors are grateful for funding through grant agreement No. 229830 IC–UP2 under the 7^th Framework Programme of the European Commission.

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