(2R,4S,5S)-5-Hy­droxy-4-methyl-3-oxohept-6-en-2-yl benzoate

Kiedrowski, V. von; God, C.; Knauer, L.; Strohmann, C.; Preut, H.; Hiersemann, M.

doi:10.1107/S2414314617015395

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 2| Part 10| October 2017| x171539

https://doi.org/10.1107/S2414314617015395

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(2R,4S,5S)-5-Hydroxy-4-methyl-3-oxohept-6-en-2-yl benzoate

Valeska von Kiedrowski,^a Claudia God,^a Lena Knauer,^a Carsten Strohmann,^a Hans Preut ^a ^* and Martin Hiersemann ^a

^aFakultät Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, 44221 Dortmund, Germany
^*Correspondence e-mail: hans.preut@tu-dortmund.de

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 14 August 2017; accepted 23 October 2017; online 27 October 2017)

The title compound, C₁₅H₁₈O₄, which crystallizes with two molecules in the asymmetric unit, was obtained in the course of the total synthesis of curvicollides A–C and fusaequisin A. It features the relative configuration of the Western aldol part of the natural products. In the crystal, molecules are linked by C—H⋯O hydrogen bonds.

Keywords: crystal structure; total synthesis; curvicollides A-C; Fusaequisin A; asymmetric aldol reaction; Paterson aldol reaction.

CCDC reference: 1581433

Structure description

The asymmetric synthesis of the title compound (I) (Fig. 1) is based on Paterson`s anti-aldol chemistry utilizing enantiomerically pure (R)-3-oxopentan-2-yl benzoate (II) synthesized in accordance to published procedures from commercially available (R)-ethyl lactate (Paterson et al., 1994 , Paterson, 1998 ). In the following hitherto unpublished example of a Paterson aldol reaction, chlorodicyclohexylborane in the presence of triethylamine was employed to generate the (E)-configured boron enolate of (R)-ethyl ketone (II), which was then treated with an excess of acroleine as the electrophile. The title compound (I) was obtained in good yields (80%) and excellent diastereoselectivities (dr > 95:5). From a synthetic perspective, compound (I) can be viewed as a versatile building block as it ensures high enantio- and diastereoselectivities as well as facile expandability in several directions. The latter is due to the fact that the benzoylated α-hydroxy ketone on one hand, and the vinyl group on the other can be orthogonally transformed into a whole variety of synthetic products. In particular, the title compound represents a synthetic precursor for the Western side chains of Curvicollides A–C (Che et al., 2004 ) and Fusaequisin A (Shiono et al., 2013 ).

Figure 1
The molecular structure of the title compound, showing the labeling of all non-H atoms. Displacement ellipsoids are shown at the 50% probability level. The asymmetric unit contains two molecules.

Compound (I) crystallizes with two molecules in the asymmetric unit (Fig. 1) with similar conformations (r.m.s. overlay fit = 0.329 Å). The absolute structure (C8 R, C11 S, C13 S; C23 R, S26 S, C28 S) is well established based on refinement of the Flack parameter (Table 2). In the crystal, weak C—H⋯O hydrogen bonds (Table 1) link the molecules.

Table 2
Experimental details

Crystal data
Chemical formula	C₁₅H₁₈O₄
M_r	262.29
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	100
a, b, c (Å)	15.6945 (8), 4.9102 (2), 20.1737 (10)
β (°)	112.712 (2)
V (Å³)	1434.10 (12)
Z	4
Radiation type	Cu Kα
μ (mm⁻¹)	0.72
Crystal size (mm)	0.98 × 0.10 × 0.08

Data collection
Diffractometer	Bruker D8 VENTURE area detector
Absorption correction	Multi-scan (SADABS; Bruker, 2012 )
T_min, T_max	0.350, 0.470
No. of measured, independent and observed [I > 2σ(I)] reflections	22281, 5396, 5143
R_int	0.051
(sin θ/λ)_max (Å⁻¹)	0.609

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.099, 1.04
No. of reflections	5396
No. of parameters	349
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.40, −0.28
Absolute structure	Flack x determined using 2185 quotients [(I⁺)−(I⁻)]/[(I⁺)+(I⁻)] (Parsons et al., 2013 )
Absolute structure parameter	0.02 (6)
Computer programs: SMART and SAINT (Bruker, 2012), SHELXD, SHELXL97 and SHELXTL-Plus (Sheldrick, 2008 ), SHELXL2013 (Sheldrick, 2015 ) and PLATON (Spek, 2009 ).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O8—H8⋯O7	0.84	2.63	3.140 (3)	120
C8—H8A⋯O3ⁱ	1.00	2.41	3.235 (3)	140
C23—H23⋯O7ⁱⁱ	1.00	2.54	3.189 (3)	122
C26—H26⋯O7ⁱⁱ	1.00	2.29	3.205 (3)	151
Symmetry codes: (i) x, y-1, z; (ii) x, y+1, z.

Synthesis and crystallization

The reaction was carried out in two parallel batches under an argon atmosphere. To a solution of the ketone (II) (C₁₂H₁₄O₃, 206.24 g mol⁻¹, 778 mg, 3.772 mmol, 1 equiv.) in Et₂O (32 ml were successively added dried 3 Å molecular sieves (200 mg, 0.1 mbar, 473 K, 1 h), chlorodicyclohexylborane (c-Hex₂BCl, 1 M in hexane, 5.79 ml, 5.79 mmol,1.53 equiv.) and triethylamine (C₆H₁₅N, 101.19 g mol⁻¹, 0.726 g mol⁻¹, 0.97 ml, 704.2 mg, 6.959 mmol, 1.84 equiv.) at 223 K. The clear, colorless suspension was stirred for 20 min at 232 K and the color of the suspension turned to white. The white, turbid suspension was cooled to 193 K and to the solution freshly distilled acrolein (C₃H₄O, 56.06 g mol⁻¹, 0.839 g ml⁻¹, 1.05 ml, 881 mg, 15.715 mmol, 4.17 equiv.) was added dropwise over a period of 10 min at 193 K. The white suspension was stirred at 193 K for 1 h and was then diluted by the addition of aqueous phosphate pH 7 buffer (20 ml and CH₂Cl₂ (20 ml). The decolorized mixture was then warmed to room temperature and transferred into a separating funnel using CH₂Cl₂ (10 ml) for rinsing. The phase were separated and the aqueous layer was extracted with CH₂Cl₂ (3 × 30 ml). The combined organic phases were dried (MgSO₄) and concentrated under reduced pressure. The oily yellowish residue was purified by flash chromatography (cyclohexane–ethyl acetate, 50:1 to 20:1 to 10:1 to 5:1) to deliver the aldol (I) (C₁₅H₁₈O₄, 262.30 g mol⁻¹, 787 mg, 3.000 mmol, 80%) as a white solid. Crystallization of (I) was accomplished from a solution in hot cyclohexane (50 ml, 333 K) by slow cooling to room temperature. The product crystallized in colorless needles: m.p. 365–369 K; R_f 0.45 (cyclohexane–ethyl acetate, 2:1); [α]_D²⁰ = −39.7 (c = 0.6 in CHCl₃); ¹H NMR (500 MHz, CDCl₃) δ 1.23 (d, ³J = 7.3 Hz, 3H), 1.57 (d, ³J = 7.0 Hz, 3H), 2.36 (d, ³J = 5.4 Hz, 1H), 2.93 (quin, ³J = 7.3 Hz, 1H), 4.24–4.30 (m, 1H), 5.21 (app d, ³J = 10.3 Hz, 1H), 5.31 (app d, ³J = 17.1 Hz, 1H), 5.44 (q, ³J = 7.0 Hz, 1H), 5.84 (ddd, ³J = 17.1, 10.3, 6.8 Hz, 1H), 7.43–7.49 (m, 2H), 7.56–7.62 (m, 1H), 8.06–8.11 (m, 2H); ¹³C NMR (151 MHz CDCl₃) δ 14.55 (CH₃), 15.84 (CH₃), 47.93 (CH), 74.91 (CH), 75.29 (CH), 117.32 (CH₂), 128.61 (CH), 129.61 (C), 129.96 (CH), 133.51 (CH), 138.40 (CH), 165.99 (C), 211.25 (C); IR ν 3330 (w), 2980 (w), 2935 (w), 1720 (s), 1605 (w), 1450 (m), 1380 (m), 1350 (m), 1315 (m), 1300 (m), 1265 (s), 1175 (w), 1115 (s), 1065 (m), 1015 (m), 1000 (s), 950 (m), 920 (m), 745 (w), 710 (s), 685 (w) cm⁻¹. Analysis calculated for C₁₅H₁₈O₄: C, 68.68; H, 6.92; found: C, 68.7; H, 7.0.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Structural data

CCDC reference: 1581433

Crystal structure: contains datablocks I, b0751. DOI: https://doi.org/10.1107/S2414314617015395/hb4163sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617015395/hb4163Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2414314617015395/hb4163Isup3.cml

checkCIF report

Computing details top

Data collection: SMART (Bruker, 2012); cell refinement: SAINT (Bruker, 2012); data reduction: SAINT (Bruker, 2012); program(s) used to solve structure: SHELXD (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015); molecular graphics: SHELXTL-Plus (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

(2R,4S,5S)-5-Hydroxy-4-methyl-3-oxohept-6-en-2-yl benzoate top

Crystal data top

C₁₅H₁₈O₄	F(000) = 560
M_r = 262.29	D_x = 1.215 Mg m⁻³
Monoclinic, P2₁	Cu Kα radiation, λ = 1.54178 Å
a = 15.6945 (8) Å	Cell parameters from 9866 reflections
b = 4.9102 (2) Å	θ = 3.1–72.5°
c = 20.1737 (10) Å	µ = 0.72 mm⁻¹
β = 112.712 (2)°	T = 100 K
V = 1434.10 (12) Å³	Needle, colourless
Z = 4	0.98 × 0.10 × 0.08 mm

Data collection top

Bruker D8 VENTURE area detector diffractometer	5396 independent reflections
Radiation source: microfocus sealed X-ray tube	5143 reflections with I > 2σ(I)
Detector resolution: 7.9 pixels mm^-1	R_int = 0.051
ω and φ scans	θ_max = 70.0°, θ_min = 3.1°
Absorption correction: multi-scan (SADABS; Bruker, 2012)	h = −19→19
T_min = 0.350, T_max = 0.470	k = −5→5
22281 measured reflections	l = −24→24

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) + (0.0606P)² + 0.212P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max < 0.001
5396 reflections	Δρ_max = 0.40 e Å⁻³
349 parameters	Δρ_min = −0.28 e Å⁻³
1 restraint	Absolute structure: Flack x determined using 2185 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons et al., 2013)
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.02 (6)

Special details top

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. H-atoms attached to C, except those in CH₃, were placed in calculated positions (C-H = 0.95-1.00Å and U_iso(H) = 1.2 U_eq(C)). CH₃ hydrogen atoms, which were taken from a Fourier map (AFIX 137), were allowed to rotate but not to tip (C-H = 0.98 Å and U_iso(H) = 1.5 U_eq(C)). H-atoms attached to O were placed in calculated positions (O-H = 0.84Å and U_iso(H) = 1.5 U_eq(C)).

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

	x	y	z	U_iso*/U_eq
O6	0.44530 (10)	0.7087 (3)	0.23069 (8)	0.0297 (3)
O2	0.97206 (10)	0.2429 (3)	0.75670 (8)	0.0267 (3)
O4	0.97357 (9)	0.3000 (3)	0.51804 (8)	0.0270 (3)
H4	0.9934	0.1438	0.5149	0.040*
O1	0.82462 (10)	0.1587 (3)	0.74079 (9)	0.0313 (4)
O8	0.53681 (11)	0.7325 (4)	0.02037 (9)	0.0355 (4)
H8	0.5035	0.6201	0.0307	0.053*
O5	0.58656 (11)	0.7084 (4)	0.31915 (9)	0.0384 (4)
O3	0.88168 (14)	0.4843 (3)	0.63246 (9)	0.0388 (4)
O7	0.54639 (18)	0.4739 (4)	0.16545 (13)	0.0567 (6)
C10	0.89931 (14)	0.2484 (4)	0.62747 (11)	0.0247 (4)
C6	0.90938 (15)	0.4881 (4)	0.82787 (11)	0.0252 (4)
C11	0.86074 (14)	0.1032 (4)	0.55512 (11)	0.0223 (4)
H11	0.8946	−0.0721	0.5585	0.027*
C21	0.46950 (15)	0.4252 (4)	0.33115 (12)	0.0256 (4)
C13	0.87508 (13)	0.2880 (4)	0.49904 (11)	0.0226 (4)
H13	0.8529	0.4749	0.5040	0.027*
C5	0.98921 (15)	0.6447 (5)	0.85657 (11)	0.0282 (4)
H5	1.0384	0.6176	0.8409	0.034*
C22	0.50808 (15)	0.6266 (5)	0.29529 (12)	0.0278 (4)
C8	0.95719 (14)	0.0841 (4)	0.69332 (11)	0.0250 (4)
H8A	0.9242	−0.0884	0.6950	0.030*
C23	0.48191 (16)	0.8800 (5)	0.19033 (12)	0.0291 (5)
H23	0.5154	1.0378	0.2205	0.035*
C7	0.89546 (14)	0.2800 (4)	0.77118 (11)	0.0243 (4)
C14	0.82627 (15)	0.1980 (5)	0.42279 (11)	0.0287 (5)
H14	0.8401	0.0236	0.4091	0.034*
C25	0.54742 (16)	0.7171 (5)	0.16606 (12)	0.0314 (5)
C20	0.37594 (16)	0.3604 (5)	0.30452 (12)	0.0308 (5)
H20	0.3340	0.4491	0.2628	0.037*
C16	0.53049 (16)	0.2961 (5)	0.39209 (13)	0.0336 (5)
H16	0.5942	0.3418	0.4104	0.040*
C15	0.76517 (17)	0.3506 (6)	0.37411 (12)	0.0371 (5)
H15A	0.7504	0.5257	0.3867	0.044*
H15B	0.7356	0.2862	0.3262	0.044*
C28	0.62499 (15)	0.7506 (5)	0.07868 (12)	0.0322 (5)
H28	0.6496	0.5616	0.0915	0.039*
C18	0.40574 (17)	0.0346 (5)	0.39970 (13)	0.0338 (5)
H18	0.3840	−0.1010	0.4229	0.041*
C12	0.75833 (15)	0.0434 (5)	0.53746 (12)	0.0304 (5)
H12A	0.7522	−0.0610	0.5768	0.046*
H12B	0.7329	−0.0624	0.4929	0.046*
H12C	0.7245	0.2153	0.5314	0.046*
C4	0.99678 (17)	0.8405 (5)	0.90809 (12)	0.0342 (5)
H4A	1.0511	0.9482	0.9274	0.041*
C19	0.34438 (16)	0.1657 (5)	0.33928 (13)	0.0343 (5)
H19	0.2805	0.1219	0.3217	0.041*
C1	0.83745 (16)	0.5302 (5)	0.85134 (13)	0.0338 (5)
H1	0.7826	0.4246	0.8318	0.041*
C17	0.49868 (17)	0.1007 (6)	0.42635 (13)	0.0359 (5)
H17	0.5405	0.0121	0.4681	0.043*
C26	0.61548 (16)	0.8774 (5)	0.14491 (12)	0.0307 (5)
H26	0.5934	1.0695	0.1339	0.037*
C3	0.92564 (18)	0.8797 (5)	0.93149 (13)	0.0371 (5)
H3	0.9315	1.0126	0.9672	0.045*
C2	0.84610 (18)	0.7253 (6)	0.90288 (13)	0.0400 (6)
H2	0.7971	0.7535	0.9187	0.048*
C9	1.05202 (17)	0.0179 (6)	0.69334 (14)	0.0389 (6)
H9A	1.0839	0.1873	0.6912	0.058*
H9B	1.0448	−0.0951	0.6515	0.058*
H9C	1.0884	−0.0813	0.7374	0.058*
C24	0.39994 (18)	0.9808 (7)	0.12633 (16)	0.0460 (7)
H24A	0.3655	0.8249	0.0984	0.069*
H24B	0.4216	1.0943	0.0960	0.069*
H24C	0.3596	1.0887	0.1430	0.069*
C29	0.6908 (2)	0.9059 (7)	0.05534 (15)	0.0485 (7)
H29	0.6718	1.0810	0.0349	0.058*
C27	0.7077 (2)	0.8744 (8)	0.21025 (15)	0.0509 (7)
H27A	0.6974	0.9289	0.2533	0.076*
H27B	0.7508	1.0020	0.2022	0.076*
H27C	0.7339	0.6904	0.2170	0.076*
C30	0.7708 (2)	0.8223 (12)	0.0606 (2)	0.0802 (14)
H30A	0.7925	0.6485	0.0807	0.096*
H30B	0.8082	0.9344	0.0444	0.096*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O6	0.0295 (7)	0.0313 (8)	0.0306 (8)	0.0010 (6)	0.0143 (6)	0.0062 (7)
O2	0.0254 (7)	0.0311 (8)	0.0252 (7)	−0.0017 (6)	0.0113 (6)	−0.0026 (6)
O4	0.0231 (7)	0.0244 (7)	0.0371 (8)	0.0000 (6)	0.0156 (6)	0.0022 (6)
O1	0.0256 (7)	0.0354 (9)	0.0338 (8)	−0.0041 (6)	0.0126 (6)	−0.0091 (7)
O8	0.0390 (8)	0.0325 (9)	0.0332 (8)	−0.0028 (7)	0.0120 (7)	−0.0013 (7)
O5	0.0304 (8)	0.0417 (10)	0.0430 (9)	−0.0039 (7)	0.0140 (7)	0.0119 (8)
O3	0.0645 (12)	0.0228 (8)	0.0302 (9)	0.0060 (8)	0.0196 (8)	−0.0015 (7)
O7	0.1004 (17)	0.0197 (9)	0.0799 (15)	−0.0014 (9)	0.0678 (14)	−0.0039 (9)
C10	0.0304 (10)	0.0210 (10)	0.0271 (10)	−0.0012 (8)	0.0160 (8)	−0.0004 (8)
C6	0.0301 (10)	0.0246 (10)	0.0192 (9)	0.0013 (8)	0.0077 (8)	0.0028 (8)
C11	0.0245 (10)	0.0200 (9)	0.0253 (10)	0.0001 (7)	0.0130 (8)	−0.0008 (8)
C21	0.0302 (11)	0.0225 (10)	0.0294 (11)	0.0006 (8)	0.0175 (9)	−0.0016 (8)
C13	0.0224 (9)	0.0229 (10)	0.0260 (10)	−0.0006 (8)	0.0130 (8)	−0.0013 (8)
C5	0.0323 (11)	0.0281 (11)	0.0213 (10)	−0.0003 (9)	0.0071 (8)	0.0041 (8)
C22	0.0302 (11)	0.0246 (10)	0.0315 (11)	0.0039 (8)	0.0152 (9)	0.0028 (9)
C8	0.0267 (10)	0.0260 (11)	0.0244 (10)	0.0020 (8)	0.0123 (8)	−0.0019 (8)
C23	0.0336 (11)	0.0253 (11)	0.0326 (11)	0.0028 (9)	0.0176 (9)	0.0041 (9)
C7	0.0246 (10)	0.0259 (10)	0.0223 (10)	0.0015 (8)	0.0088 (8)	0.0021 (8)
C14	0.0319 (11)	0.0296 (11)	0.0291 (11)	−0.0054 (9)	0.0168 (9)	−0.0055 (9)
C25	0.0446 (13)	0.0223 (12)	0.0324 (12)	0.0001 (9)	0.0205 (10)	−0.0028 (9)
C20	0.0301 (11)	0.0341 (12)	0.0306 (11)	0.0002 (9)	0.0145 (9)	−0.0011 (9)
C16	0.0279 (11)	0.0401 (13)	0.0348 (12)	−0.0007 (9)	0.0145 (9)	0.0059 (10)
C15	0.0368 (12)	0.0470 (14)	0.0261 (11)	−0.0045 (10)	0.0107 (10)	−0.0018 (10)
C28	0.0351 (11)	0.0318 (12)	0.0331 (12)	0.0018 (10)	0.0167 (10)	−0.0053 (10)
C18	0.0430 (13)	0.0312 (12)	0.0363 (12)	−0.0046 (10)	0.0254 (11)	−0.0001 (10)
C12	0.0276 (11)	0.0349 (12)	0.0327 (11)	−0.0033 (9)	0.0161 (9)	0.0009 (9)
C4	0.0399 (12)	0.0316 (12)	0.0244 (10)	−0.0055 (9)	0.0049 (9)	0.0017 (9)
C19	0.0325 (11)	0.0396 (13)	0.0355 (12)	−0.0077 (10)	0.0184 (10)	−0.0045 (10)
C1	0.0319 (12)	0.0396 (13)	0.0316 (12)	−0.0028 (10)	0.0140 (9)	−0.0076 (10)
C17	0.0371 (12)	0.0396 (13)	0.0344 (12)	0.0029 (10)	0.0176 (10)	0.0100 (10)
C26	0.0389 (12)	0.0249 (10)	0.0350 (11)	0.0001 (9)	0.0216 (10)	−0.0041 (9)
C3	0.0495 (14)	0.0340 (12)	0.0242 (10)	0.0017 (11)	0.0103 (10)	−0.0060 (10)
C2	0.0420 (13)	0.0467 (14)	0.0342 (12)	0.0023 (11)	0.0180 (10)	−0.0086 (11)
C9	0.0295 (12)	0.0530 (15)	0.0364 (13)	0.0085 (11)	0.0150 (10)	−0.0009 (11)
C24	0.0382 (13)	0.0566 (17)	0.0464 (15)	0.0067 (12)	0.0197 (12)	0.0228 (13)
C29	0.0509 (16)	0.0613 (18)	0.0454 (15)	−0.0170 (14)	0.0318 (13)	−0.0216 (14)
C27	0.0509 (16)	0.0655 (19)	0.0360 (14)	−0.0105 (14)	0.0164 (12)	−0.0122 (14)
C30	0.0534 (19)	0.130 (4)	0.071 (2)	−0.019 (2)	0.0389 (17)	−0.038 (3)

Geometric parameters (Å, º) top

O6—C22	1.356 (3)	C16—C17	1.383 (3)
O6—C23	1.436 (3)	C16—H16	0.9500
O2—C7	1.355 (2)	C15—H15A	0.9500
O2—C8	1.438 (2)	C15—H15B	0.9500
O4—C13	1.443 (2)	C28—C29	1.499 (4)
O4—H4	0.8400	C28—C26	1.533 (3)
O1—C7	1.200 (3)	C28—H28	1.0000
O8—C28	1.432 (3)	C18—C17	1.384 (4)
O8—H8	0.8400	C18—C19	1.386 (4)
O5—C22	1.205 (3)	C18—H18	0.9500
O3—C10	1.204 (3)	C12—H12A	0.9800
O7—C25	1.194 (3)	C12—H12B	0.9800
C10—C8	1.519 (3)	C12—H12C	0.9800
C10—C11	1.524 (3)	C4—C3	1.383 (4)
C6—C5	1.392 (3)	C4—H4A	0.9500
C6—C1	1.398 (3)	C19—H19	0.9500
C6—C7	1.486 (3)	C1—C2	1.381 (4)
C11—C13	1.533 (3)	C1—H1	0.9500
C11—C12	1.534 (3)	C17—H17	0.9500
C11—H11	1.0000	C26—C27	1.536 (4)
C21—C16	1.386 (3)	C26—H26	1.0000
C21—C20	1.392 (3)	C3—C2	1.382 (4)
C21—C22	1.485 (3)	C3—H3	0.9500
C13—C14	1.496 (3)	C2—H2	0.9500
C13—H13	1.0000	C9—H9A	0.9800
C5—C4	1.387 (3)	C9—H9B	0.9800
C5—H5	0.9500	C9—H9C	0.9800
C8—C9	1.523 (3)	C24—H24A	0.9800
C8—H8A	1.0000	C24—H24B	0.9800
C23—C24	1.511 (3)	C24—H24C	0.9800
C23—C25	1.525 (3)	C29—C30	1.286 (5)
C23—H23	1.0000	C29—H29	0.9500
C14—C15	1.311 (4)	C27—H27A	0.9800
C14—H14	0.9500	C27—H27B	0.9800
C25—C26	1.515 (3)	C27—H27C	0.9800
C20—C19	1.386 (3)	C30—H30A	0.9500
C20—H20	0.9500	C30—H30B	0.9500

C22—O6—C23	114.68 (17)	O8—C28—C26	110.66 (18)
C7—O2—C8	114.31 (16)	C29—C28—C26	112.2 (2)
C13—O4—H4	109.5	O8—C28—H28	108.0
C28—O8—H8	109.5	C29—C28—H28	108.0
O3—C10—C8	121.1 (2)	C26—C28—H28	108.0
O3—C10—C11	120.7 (2)	C17—C18—C19	120.2 (2)
C8—C10—C11	118.12 (17)	C17—C18—H18	119.9
C5—C6—C1	119.5 (2)	C19—C18—H18	119.9
C5—C6—C7	122.80 (19)	C11—C12—H12A	109.5
C1—C6—C7	117.7 (2)	C11—C12—H12B	109.5
C10—C11—C13	108.21 (16)	H12A—C12—H12B	109.5
C10—C11—C12	107.76 (16)	C11—C12—H12C	109.5
C13—C11—C12	112.39 (17)	H12A—C12—H12C	109.5
C10—C11—H11	109.5	H12B—C12—H12C	109.5
C13—C11—H11	109.5	C3—C4—C5	120.4 (2)
C12—C11—H11	109.5	C3—C4—H4A	119.8
C16—C21—C20	120.2 (2)	C5—C4—H4A	119.8
C16—C21—C22	117.7 (2)	C20—C19—C18	120.2 (2)
C20—C21—C22	122.1 (2)	C20—C19—H19	119.9
O4—C13—C14	110.86 (16)	C18—C19—H19	119.9
O4—C13—C11	106.00 (16)	C2—C1—C6	120.0 (2)
C14—C13—C11	114.91 (17)	C2—C1—H1	120.0
O4—C13—H13	108.3	C6—C1—H1	120.0
C14—C13—H13	108.3	C16—C17—C18	119.9 (2)
C11—C13—H13	108.3	C16—C17—H17	120.1
C4—C5—C6	119.9 (2)	C18—C17—H17	120.1
C4—C5—H5	120.1	C25—C26—C28	110.55 (18)
C6—C5—H5	120.1	C25—C26—C27	106.7 (2)
O5—C22—O6	122.4 (2)	C28—C26—C27	111.5 (2)
O5—C22—C21	125.0 (2)	C25—C26—H26	109.3
O6—C22—C21	112.60 (19)	C28—C26—H26	109.3
O2—C8—C10	109.07 (16)	C27—C26—H26	109.3
O2—C8—C9	107.01 (18)	C2—C3—C4	119.9 (2)
C10—C8—C9	111.59 (18)	C2—C3—H3	120.0
O2—C8—H8A	109.7	C4—C3—H3	120.0
C10—C8—H8A	109.7	C1—C2—C3	120.4 (2)
C9—C8—H8A	109.7	C1—C2—H2	119.8
O6—C23—C24	106.33 (18)	C3—C2—H2	119.8
O6—C23—C25	109.98 (18)	C8—C9—H9A	109.5
C24—C23—C25	110.8 (2)	C8—C9—H9B	109.5
O6—C23—H23	109.9	H9A—C9—H9B	109.5
C24—C23—H23	109.9	C8—C9—H9C	109.5
C25—C23—H23	109.9	H9A—C9—H9C	109.5
O1—C7—O2	123.20 (19)	H9B—C9—H9C	109.5
O1—C7—C6	124.51 (19)	C23—C24—H24A	109.5
O2—C7—C6	112.29 (17)	C23—C24—H24B	109.5
C15—C14—C13	122.5 (2)	H24A—C24—H24B	109.5
C15—C14—H14	118.7	C23—C24—H24C	109.5
C13—C14—H14	118.7	H24A—C24—H24C	109.5
O7—C25—C26	121.7 (2)	H24B—C24—H24C	109.5
O7—C25—C23	121.3 (2)	C30—C29—C28	125.5 (4)
C26—C25—C23	117.00 (19)	C30—C29—H29	117.2
C19—C20—C21	119.5 (2)	C28—C29—H29	117.2
C19—C20—H20	120.3	C26—C27—H27A	109.5
C21—C20—H20	120.3	C26—C27—H27B	109.5
C17—C16—C21	120.1 (2)	H27A—C27—H27B	109.5
C17—C16—H16	120.0	C26—C27—H27C	109.5
C21—C16—H16	120.0	H27A—C27—H27C	109.5
C14—C15—H15A	120.0	H27B—C27—H27C	109.5
C14—C15—H15B	120.0	C29—C30—H30A	120.0
H15A—C15—H15B	120.0	C29—C30—H30B	120.0
O8—C28—C29	109.8 (2)	H30A—C30—H30B	120.0

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O8—H8···O7	0.84	2.63	3.140 (3)	120
C8—H8A···O3ⁱ	1.00	2.41	3.235 (3)	140
C23—H23···O7ⁱⁱ	1.00	2.54	3.189 (3)	122
C26—H26···O7ⁱⁱ	1.00	2.29	3.205 (3)	151

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

Funding information

We acknowledge financial support by the Deutsche Forschungsgemeinschaft and TU Dortmund, Technical University Dortmund within the funding program: Open Access Publishing.

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