Related literature {#sec1}
==================

For the occurrence of the title compound in human breast milk and the fatty tissue of fish, see: Valdersnes *et al.* (2006[@bb12]). The title compound is the product of an esterification of 3,5,5,6,8,8-hexa­methyl-5,6,7,8-tetra­hydro­naphthalene-2-carb­oxy­lic acid (AHTN---COOH) with methanol. For the synthesis of the acid, see: Kuhlich *et al.* (2010[@bb9]); Valdersnes *et al.* (2006[@bb12]). For the crystal structures of AHTN and AHTN--COOH, see: De Ridder *et al.* (1990[@bb5]) and Kuhlich *et al.* (2010[@bb9]), respectively. For the environmental occurrence and estrogenic activity of AHTN, see: Heberer (2003[@bb8]); Bitsch *et al.* (2002[@bb2]). For puckering parameters, see: Cremer & Pople (1975[@bb4]).

Experimental {#sec2}
============

 {#sec2.1}

### Crystal data {#sec2.1.1}

C~18~H~26~O~2~*M* *~r~* = 274.39Monoclinic,*a* = 11.5049 (11) Å*b* = 11.9482 (5) Å*c* = 12.1078 (13) Åβ = 102.612 (5)°*V* = 1624.2 (2) Å^3^*Z* = 4Cu *K*α radiationμ = 0.55 mm^−1^*T* = 193 K0.45 × 0.40 × 0.30 mm

### Data collection {#sec2.1.2}

Enraf--Nonius CAD-4 diffractometer5083 measured reflections3062 independent reflections2856 reflections with *I* \> 2σ(*I*)*R* ~int~ = 0.0473 standard reflections every 60 min intensity decay: 3%

### Refinement {#sec2.1.3}

*R*\[*F* ^2^ \> 2σ(*F* ^2^)\] = 0.054*wR*(*F* ^2^) = 0.152*S* = 1.033062 reflections216 parameters10 restraintsH-atom parameters constrainedΔρ~max~ = 0.29 e Å^−3^Δρ~min~ = −0.26 e Å^−3^

 {#d5e408}

Data collection: *CAD-4 Software* (Enraf--Nonius, 1989[@bb7]); cell refinement: *CAD-4 Software*; data reduction: *CORINC* (Dräger & Gattow, 1971[@bb6]); program(s) used to solve structure: *SIR97* (Altomare *et al.*, 1999[@bb1]); program(s) used to refine structure: *SHELXTL* (Sheldrick, 2008[@bb10]); molecular graphics: *PLATON* (Spek, 2009[@bb11]); software used to prepare material for publication: *PLATON*.

Supplementary Material
======================

Crystal structure: contains datablocks I, global. DOI: [10.1107/S1600536811002601/zl2346sup1.cif](http://dx.doi.org/10.1107/S1600536811002601/zl2346sup1.cif)

Structure factors: contains datablocks I. DOI: [10.1107/S1600536811002601/zl2346Isup2.hkl](http://dx.doi.org/10.1107/S1600536811002601/zl2346Isup2.hkl)

Additional supplementary materials: [crystallographic information](http://scripts.iucr.org/cgi-bin/sendsupfiles?zl2346&file=zl2346sup0.html&mime=text/html); [3D view](http://scripts.iucr.org/cgi-bin/sendcif?zl2346sup1&Qmime=cif); [checkCIF report](http://scripts.iucr.org/cgi-bin/paper?zl2346&checkcif=yes)

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: [ZL2346](http://scripts.iucr.org/cgi-bin/sendsup?zl2346)).

The authors want to thank Dr Dietmar Pfeifer (BAM, Berlin) for a helpful discussion regarding the inter­pretation of the NMR data.

Comment
=======

The title compound is the product of an esterification of 3,5,5,6,8,8-hexamethyl-5,6,7,8- tetrahydronaphthalene-2-carboxylic acid (AHTN-COOH) with methanol. AHTN-COOH itself is the product of a haloform reaction from 1-(3,5,5,6,8,8-hexamethyl-5,6,7,8- tetrahydronaphthalen-2-yl)ethan-1-one (AHTN) and sodium hypochlorite solution. Two slightly different syntheses of AHTN-COOH are described by Kuhlich *et al.* (2010) and by Valdersnes *et al.* (2006). The crystal structure of AHTN-COOH was described previously by Kuhlich *et al.* (2010). The crystal structure of AHTN was determined by De Ridder *et al.* (1990).

The title compound can either be obtained in a two-step synthesis, described by Valdersnes *et al.* (2006) or, as described here, in a one-step procedure (see Experimental).

AHTN itself is a widely used fragrance in cosmetics and cleaning products. It is introduced into the environment mainly via sewage treatment plants and can be found in surface water at low µg/*L* concentration (Heberer, 2003). It is in focus of interest due to its low estrogenic potential (Bitsch *et al.*, 2002). Due to their structural similarities to AHTN, the title compound and AHTN-COOH might also have estrogenic or even toxic properties themselves.

The title compound was found in human breast milk and piscine fatty tissue by Valdersnes *et al.* (2006) proofing its ubiquitary occurrence.

The molecule crystallizes in the monoclinic space group *P*2~1~/n. The molecular structure of the compound and the atom-labeling scheme are shown in Fig 1. The structure is disordered in the non aromatic ring. This disorder can be described as pseudo mirror-symmetric with respect to the aromatic ring\'s plane, resulting in two moieties (ratio 0.744 (3):0.256 (3)).

A general puckering analysis according to Cremer and Pople (Cremer & Pople, 1975) led to a half-chair conformation for both enantiomers. The S-enantiomer (C4-C5-C9-C10B-C11B-C12) has a puckering amplitude (Q) of 0.526 (6) Å and 0.502 (2) Å for the R-enantiomer (C4-C5-C9-C10-C11-C12), respectively. The maximum deviation from planarity for C11/C11B is -0.3587 (39) of the R-enantiomer and 0.3335 (14) of the S-enantiomer, respectively, proofing the nearly mirror-symmetric setup.

Each molecule is surrounded by three next neighbors, whereas the centroids of the molecules are arranged in sheets parallel to the (202) plane.

A detailed description of the disorder treatment can be found in the refinement section. The molecules form pairs *via* non classical hydrogen bonds (C18---H26···O2) (see dashed green bonds in Fig. 2).

Experimental {#experimental}
============

The methyl ester of 1-(3,5,5,6,8,8-hexamethyl-5,6,7,8- tetrahydronaphthalen-2-yl)ethan-1-one (AHTN) was synthesized by stirring a solution of 1 mg AHTN dissolved in 100 mL methanol and 50 mL 10% sodium hypochlorite solution at room temperature. After 24 h of stirring precipitated sodium chloride was dissolved with water and the organic compound was extracted three times with 50 mL ethyl acetate each. The organic solvents were combined, washed with water and dried with sodium sulfate. For single-crystal X-ray crystallography white and clear crystals of the title compound were grown by solvent evaporation (ethyl acetate) at ambient temperature over a period of three days \[m.p. 348 K\]. IR (ν, cm^-1^): 1720(*s*), 1687(*s*), 1609(*s*), 1550(*s*), 1495(*s*), 1435(*s*), 1390(*s*), 1360(*s*), 1298(*s*), 1255(*s*), 1245(*s*), 1191(*s*), 1141(*s*), 1103(*s*), 1021(*s*), 980(*s*), 944(*s*), 916(*s*); ^1^H-NMR (500 MHz, CD~3~OD, TMS): δ = 7.83 (1*H*, s), 7.23 (1*H*, s), 3.83 (3*H*, s), 2.48 (3*H*, s), 1.85 (1*H*, ddq, *J*~H,H\'~=2.7 Hz, *J*~H,H\'\'~=13.2 Hz, *J*~H,Me~=6.9 Hz), 1.61 (1*H*, dd, ^2^*J*=13.6 Hz, ^3^*J*=13.2 Hz), 1.38 (1*H*, dd, ^2^*J*=13.6 Hz, ^3^*J*=2.7 Hz), 1.30 (3*H*, s), 1.26 (3*H*, s), 1.22 (3*H*, s), 1.04 (3*H*, s), 0.98 (3*H*, d, *J*=6.9 Hz); ^13^C-NMR (125 MHz, CD~3~OD, TMS): δ = 169.7, 151.8, 143.5, 137.8, 131.8, 130.2, 127.8, 52.1, 44.6, 38.9, 35.7, 34.9, 32.6, 32.4, 28.9, 25.1, 21.7, 17.1; (+)-ESI/MS: 275.6 (60) \[*M*+H^+^\], 297.5 (100) \[*M*+Na^+^\].

Refinement {#refinement}
==========

The structure exhibits disorder originating from two possible half chair conformations in the non aromatic ring. The significant disorder around the atoms of the non aromatic ring was taken into account and the refinement was improved by introducing split positions for the atoms C10, C11, C13, C14, C15, C16 and C17. Equivalent bond distances within the two moieties were restrained to be the same within a standard deviation of 0.02Å, and equivalent disordered atoms were constrained to have identical ADPs. Refinement of the occupancy ratio converged to a value of 74.4 (3)% for the major and 25.6 (3)% for the minor moiety, respectively.

Hydrogen atoms were placed in calculated positions with C---H distances of 0.98 (CH~3~), 0.99 (CH~2~), 1.00 (CH~sat~), and 0.95 (CH~arom~) with *U*~iso~(H) = 1.2 of the parent atom *U*~eq~ or 1.5 *U*~eq~(C~methyl~).

Figures
=======

![: Left: ORTEP representation of the title compound with atomic labeling shown with 30% probability displacement ellipsoids. Right: Atoms belonging to the minor disordered moiety and their bonds are presented in light gray and as thin black lines respectively. Hydrogen atoms are omitted for the sake of clarity.](e-67-0o485-fig1){#Fap1}

![: View of the unit cell of the title compound along \[010\]. Hydrogen bonds are drawn as dashed green lines. The minor disordered moiety is omitted for clarity.](e-67-0o485-fig2){#Fap2}

Crystal data {#tablewrapcrystaldatalong}
============

  ------------------------- -------------------------------------
  C~18~H~26~O~2~            *F*(000) = 600
  *M~r~* = 274.39           *D*~x~ = 1.122 Mg m^−3^
  Monoclinic, *P*2~1~/*n*   Cu *K*α radiation, λ = 1.54178 Å
  Hall symbol: -P 2yn       Cell parameters from 25 reflections
  *a* = 11.5049 (11) Å      θ = 65--69°
  *b* = 11.9482 (5) Å       µ = 0.55 mm^−1^
  *c* = 12.1078 (13) Å      *T* = 193 K
  β = 102.612 (5)°          Block, colourless
  *V* = 1624.2 (2) Å^3^     0.45 × 0.40 × 0.30 mm
  *Z* = 4                   
  ------------------------- -------------------------------------

Data collection {#tablewrapdatacollectionlong}
===============

  -------------------------------------- -------------------------------------
  Enraf--Nonius CAD-4 diffractometer     *R*~int~ = 0.047
  Radiation source: rotating anode       θ~max~ = 69.8°, θ~min~ = 4.8°
  graphite                               *h* = 0→14
  ω/2θ scans                             *k* = −14→14
  5083 measured reflections              *l* = −14→14
  3062 independent reflections           3 standard reflections every 60 min
  2856 reflections with *I* \> 2σ(*I*)   intensity decay: 3%
  -------------------------------------- -------------------------------------

Refinement {#tablewraprefinementdatalong}
==========

  ---------------------------------------------------------------- ---------------------------------------------------------------------------------------------------
  Refinement on *F*^2^                                             Secondary atom site location: difference Fourier map
  Least-squares matrix: full                                       Hydrogen site location: inferred from neighbouring sites
  *R*\[*F*^2^ \> 2σ(*F*^2^)\] = 0.054                              H-atom parameters constrained
  *wR*(*F*^2^) = 0.152                                             *w* = 1/\[σ^2^(*F*~o~^2^) + (0.0889*P*)^2^ + 0.4305*P*\] where *P* = (*F*~o~^2^ + 2*F*~c~^2^)/3
  *S* = 1.03                                                       (Δ/σ)~max~ = 0.001
  3062 reflections                                                 Δρ~max~ = 0.29 e Å^−3^
  216 parameters                                                   Δρ~min~ = −0.26 e Å^−3^
  10 restraints                                                    Extinction correction: *SHELXTL* (Sheldrick, 2008), Fc^\*^=kFc\[1+0.001xFc^2^λ^3^/sin(2θ)\]^-1/4^
  Primary atom site location: structure-invariant direct methods   Extinction coefficient: 0.0070 (8)
  ---------------------------------------------------------------- ---------------------------------------------------------------------------------------------------

Special details {#specialdetails}
===============

  ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
  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 F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ \> 2sigma(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ 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 (Å^2^) {#tablewrapcoords}
==================================================================================================

  ------ -------------- -------------- --------------- -------------------- ------------
         *x*            *y*            *z*             *U*~iso~\*/*U*~eq~   Occ. (\<1)
  O1     0.34558 (10)   1.32637 (9)    −0.02324 (9)    0.0454 (3)           
  O2     0.44327 (15)   1.40647 (10)   0.13483 (11)    0.0711 (5)           
  C1     0.40482 (12)   1.32335 (11)   0.08442 (12)    0.0353 (3)           
  C2     0.41364 (11)   1.20805 (11)   0.13210 (10)    0.0283 (3)           
  C3     0.34903 (11)   1.12216 (11)   0.06975 (10)    0.0284 (3)           
  H23    0.2999         1.1396         −0.0020         0.034\*              
  C4     0.35277 (10)   1.01170 (11)   0.10740 (10)    0.0267 (3)           
  C5     0.42442 (11)   0.98674 (11)   0.21369 (10)    0.0280 (3)           
  C6     0.48890 (11)   1.07419 (11)   0.27540 (10)    0.0310 (3)           
  H4     0.5373         1.0571         0.3476          0.037\*              
  C7     0.48699 (11)   1.18407 (11)   0.23842 (10)    0.0297 (3)           
  C8     0.56520 (13)   1.26927 (13)   0.31130 (12)    0.0412 (4)           
  H1     0.6091         1.2331         0.3806          0.062\*              
  H2     0.5156         1.3295         0.3310          0.062\*              
  H3     0.6217         1.3005         0.2696          0.062\*              
  C9     0.43809 (13)   0.86813 (12)   0.26390 (11)    0.0358 (4)           
  C10    0.33564 (19)   0.79143 (16)   0.19751 (16)    0.0364 (5)           0.744 (3)
  H16    0.2599         0.8165         0.2176          0.044\*              0.744 (3)
  C11    0.32069 (18)   0.80706 (15)   0.07020 (16)    0.0352 (4)           0.744 (3)
  H11    0.3979         0.7929         0.0493          0.042\*              0.744 (3)
  H12    0.2627         0.7515         0.0302          0.042\*              0.744 (3)
  C15    0.3518 (4)     0.6672 (3)     0.2281 (5)      0.0516 (9)           0.744 (3)
  H13    0.2785         0.6265         0.1949          0.077\*              0.744 (3)
  H14    0.3692         0.6587         0.3106          0.077\*              0.744 (3)
  H15    0.4180         0.6368         0.1984          0.077\*              0.744 (3)
  C10B   0.3875 (6)     0.7792 (5)     0.1773 (5)      0.0364 (5)           0.256 (3)
  H16B   0.4408         0.7776         0.1222          0.044\*              0.256 (3)
  C11B   0.2689 (5)     0.8159 (4)     0.1118 (5)      0.0352 (4)           0.256 (3)
  H11B   0.2177         0.8350         0.1651          0.042\*              0.256 (3)
  H12B   0.2307         0.7532         0.0638          0.042\*              0.256 (3)
  C15B   0.3853 (14)    0.6606 (11)    0.2212 (16)     0.0516 (9)           0.256 (3)
  H13B   0.4661         0.6383         0.2595          0.077\*              0.256 (3)
  H14B   0.3559         0.6098         0.1577          0.077\*              0.256 (3)
  H15B   0.3327         0.6569         0.2747          0.077\*              0.256 (3)
  C12    0.27785 (11)   0.92416 (11)   0.03173 (11)    0.0318 (3)           
  C13    0.1469 (4)     0.9422 (4)     0.0305 (4)      0.0414 (9)           0.744 (3)
  H5     0.0990         0.8866         −0.0190         0.062\*              0.744 (3)
  H6     0.1232         1.0176         0.0023          0.062\*              0.744 (3)
  H7     0.1339         0.9342         0.1075          0.062\*              0.744 (3)
  C14    0.2948 (2)     0.93749 (19)   −0.09371 (18)   0.0374 (5)           0.744 (3)
  H8     0.3800         0.9388         −0.0936         0.056\*              0.744 (3)
  H9     0.2580         1.0076         −0.1258         0.056\*              0.744 (3)
  H10    0.2570         0.8744         −0.1395         0.056\*              0.744 (3)
  C16    0.4257 (4)     0.8693 (6)     0.3874 (3)      0.0576 (11)          0.744 (3)
  H17    0.4953         0.9059         0.4345          0.086\*              0.744 (3)
  H18    0.4202         0.7922         0.4135          0.086\*              0.744 (3)
  H19    0.3535         0.9104         0.3930          0.086\*              0.744 (3)
  C17    0.5617 (2)     0.8238 (2)     0.2576 (2)      0.0464 (6)           0.744 (3)
  H20    0.5676         0.8189         0.1782          0.070\*              0.744 (3)
  H21    0.5734         0.7494         0.2923          0.070\*              0.744 (3)
  H22    0.6230         0.8749         0.2982          0.070\*              0.744 (3)
  C13B   0.1450 (11)    0.9619 (14)    0.0068 (14)     0.0414 (9)           0.256 (3)
  H5B    0.0939         0.8991         −0.0254         0.062\*              0.256 (3)
  H6B    0.1334         1.0242         −0.0473         0.062\*              0.256 (3)
  H7B    0.1241         0.9862         0.0773          0.062\*              0.256 (3)
  C14B   0.3189 (7)     0.8985 (6)     −0.0673 (6)     0.0374 (5)           0.256 (3)
  H8B    0.3208         0.9670         −0.1115         0.056\*              0.256 (3)
  H9B    0.2652         0.8441         −0.1128         0.056\*              0.256 (3)
  H10B   0.3993         0.8668         −0.0462         0.056\*              0.256 (3)
  C16B   0.3894 (15)    0.876 (2)      0.3749 (13)     0.0576 (11)          0.256 (3)
  H17B   0.4310         0.9355         0.4231          0.086\*              0.256 (3)
  H18B   0.4029         0.8042         0.4155          0.086\*              0.256 (3)
  H19B   0.3038         0.8918         0.3554          0.086\*              0.256 (3)
  C17B   0.5738 (8)     0.8426 (8)     0.3014 (7)      0.0464 (6)           0.256 (3)
  H20B   0.6116         0.8534         0.2371          0.070\*              0.256 (3)
  H21B   0.5851         0.7651         0.3279          0.070\*              0.256 (3)
  H22B   0.6101         0.8934         0.3629          0.070\*              0.256 (3)
  C18    0.33250 (17)   1.43507 (14)   −0.07628 (16)   0.0561 (5)           
  H24    0.2983         1.4873         −0.0297         0.084\*              
  H25    0.2796         1.4293         −0.1514         0.084\*              
  H26    0.4107         1.4624         −0.0838         0.084\*              
  ------ -------------- -------------- --------------- -------------------- ------------

Atomic displacement parameters (Å^2^) {#tablewrapadps}
=====================================

  ------ ------------- ------------- ------------- -------------- ------------- --------------
         *U*^11^       *U*^22^       *U*^33^       *U*^12^        *U*^13^       *U*^23^
  O1     0.0551 (7)    0.0345 (6)    0.0423 (6)    −0.0050 (5)    0.0009 (5)    0.0096 (4)
  O2     0.1106 (12)   0.0323 (6)    0.0585 (8)    −0.0166 (7)    −0.0076 (7)   0.0010 (5)
  C1     0.0362 (7)    0.0302 (7)    0.0399 (7)    −0.0030 (5)    0.0091 (6)    0.0000 (5)
  C2     0.0269 (6)    0.0288 (7)    0.0313 (6)    0.0003 (5)     0.0108 (5)    −0.0009 (5)
  C3     0.0272 (6)    0.0312 (7)    0.0270 (6)    0.0007 (5)     0.0066 (5)    −0.0006 (5)
  C4     0.0252 (6)    0.0293 (7)    0.0275 (6)    0.0000 (5)     0.0101 (5)    −0.0018 (5)
  C5     0.0292 (6)    0.0312 (7)    0.0268 (6)    0.0023 (5)     0.0130 (5)    0.0012 (5)
  C6     0.0320 (7)    0.0372 (7)    0.0243 (6)    0.0022 (5)     0.0072 (5)    −0.0009 (5)
  C7     0.0277 (6)    0.0342 (7)    0.0289 (6)    −0.0004 (5)    0.0101 (5)    −0.0066 (5)
  C8     0.0415 (8)    0.0406 (8)    0.0388 (7)    −0.0035 (6)    0.0031 (6)    −0.0098 (6)
  C9     0.0452 (8)    0.0337 (7)    0.0306 (7)    0.0020 (6)     0.0132 (5)    0.0062 (5)
  C10    0.0429 (12)   0.0309 (9)    0.0411 (10)   −0.0002 (9)    0.0216 (8)    0.0049 (7)
  C11    0.0417 (10)   0.0276 (9)    0.0390 (10)   −0.0032 (7)    0.0149 (7)    −0.0046 (7)
  C15    0.066 (3)     0.0331 (10)   0.0607 (13)   −0.0013 (14)   0.0255 (19)   0.0079 (8)
  C10B   0.0429 (12)   0.0309 (9)    0.0411 (10)   −0.0002 (9)    0.0216 (8)    0.0049 (7)
  C11B   0.0417 (10)   0.0276 (9)    0.0390 (10)   −0.0032 (7)    0.0149 (7)    −0.0046 (7)
  C15B   0.066 (3)     0.0331 (10)   0.0607 (13)   −0.0013 (14)   0.0255 (19)   0.0079 (8)
  C12    0.0322 (7)    0.0292 (7)    0.0340 (7)    −0.0025 (5)    0.0073 (5)    −0.0034 (5)
  C13    0.0314 (8)    0.043 (2)     0.052 (2)     −0.0091 (10)   0.0133 (11)   −0.0071 (14)
  C14    0.0466 (13)   0.0345 (13)   0.0325 (11)   −0.0042 (9)    0.0117 (9)    −0.0053 (8)
  C16    0.091 (3)     0.0511 (14)   0.0374 (14)   0.006 (3)      0.029 (2)     0.0144 (12)
  C17    0.0529 (12)   0.0383 (13)   0.0484 (16)   0.0109 (9)     0.0119 (13)   0.0057 (12)
  C13B   0.0314 (8)    0.043 (2)     0.052 (2)     −0.0091 (10)   0.0133 (11)   −0.0071 (14)
  C14B   0.0466 (13)   0.0345 (13)   0.0325 (11)   −0.0042 (9)    0.0117 (9)    −0.0053 (8)
  C16B   0.091 (3)     0.0511 (14)   0.0374 (14)   0.006 (3)      0.029 (2)     0.0144 (12)
  C17B   0.0529 (12)   0.0383 (13)   0.0484 (16)   0.0109 (9)     0.0119 (13)   0.0057 (12)
  C18    0.0646 (11)   0.0412 (9)    0.0583 (10)   −0.0050 (8)    0.0038 (8)    0.0200 (7)
  ------ ------------- ------------- ------------- -------------- ------------- --------------

Geometric parameters (Å, °) {#tablewrapgeomlong}
===========================

  ----------------------- -------------- -------------------------- --------------
  O1---C1                 1.3330 (17)    C11B---H11B                0.9900
  O1---C18                1.4422 (18)    C11B---H12B                0.9900
  O2---C1                 1.1986 (18)    C15B---H13B                0.9800
  C1---C2                 1.4886 (18)    C15B---H14B                0.9800
  C2---C3                 1.3895 (18)    C15B---H15B                0.9800
  C2---C7                 1.4060 (18)    C12---C14B                 1.415 (7)
  C3---C4                 1.3939 (18)    C12---C13                  1.519 (4)
  C3---H23                0.9500         C12---C13B                 1.559 (12)
  C4---C5                 1.4005 (18)    C12---C14                  1.581 (2)
  C4---C12                1.5270 (17)    C13---H5                   0.9800
  C5---C6                 1.3994 (18)    C13---H6                   0.9800
  C5---C9                 1.5365 (18)    C13---H7                   0.9800
  C6---C7                 1.3858 (19)    C14---H8                   0.9800
  C6---H4                 0.9500         C14---H9                   0.9800
  C7---C8                 1.5092 (18)    C14---H10                  0.9800
  C8---H1                 0.9800         C16---H17                  0.9800
  C8---H2                 0.9800         C16---H18                  0.9800
  C8---H3                 0.9800         C16---H19                  0.9800
  C9---C10B               1.517 (6)      C17---H20                  0.9800
  C9---C16                1.532 (4)      C17---H21                  0.9800
  C9---C17                1.535 (3)      C17---H22                  0.9800
  C9---C17B               1.558 (9)      C13B---H5B                 0.9800
  C9---C16B               1.567 (12)     C13B---H6B                 0.9800
  C9---C10                1.569 (2)      C13B---H7B                 0.9800
  C10---C11               1.525 (3)      C14B---H8B                 0.9800
  C10---C15               1.531 (4)      C14B---H9B                 0.9800
  C10---H16               1.0000         C14B---H10B                0.9800
  C11---C12               1.522 (2)      C16B---H17B                0.9800
  C11---H11               0.9900         C16B---H18B                0.9800
  C11---H12               0.9900         C16B---H19B                0.9800
  C15---H13               0.9800         C17B---H20B                0.9800
  C15---H14               0.9800         C17B---H21B                0.9800
  C15---H15               0.9800         C17B---H22B                0.9800
  C10B---C11B             1.487 (8)      C18---H24                  0.9800
  C10B---C15B             1.515 (13)     C18---H25                  0.9800
  C10B---H16B             1.0000         C18---H26                  0.9800
  C11B---C12              1.633 (5)                                 
                                                                    
  C1---O1---C18           116.18 (12)    C12---C11B---H12B          109.1
  O2---C1---O1            121.91 (13)    H11B---C11B---H12B         107.9
  O2---C1---C2            125.66 (13)    C10B---C15B---H13B         109.5
  O1---C1---C2            112.42 (11)    C10B---C15B---H14B         109.5
  C3---C2---C7            119.33 (12)    H13B---C15B---H14B         109.5
  C3---C2---C1            119.32 (11)    C10B---C15B---H15B         109.5
  C7---C2---C1            121.35 (12)    H13B---C15B---H15B         109.5
  C2---C3---C4            123.16 (11)    H14B---C15B---H15B         109.5
  C2---C3---H23           118.4          C14B---C12---C13           122.5 (4)
  C4---C3---H23           118.4          C14B---C12---C11           85.1 (3)
  C3---C4---C5            118.17 (11)    C13---C12---C11            112.82 (19)
  C3---C4---C12           118.64 (11)    C14B---C12---C4            114.0 (3)
  C5---C4---C12           123.19 (12)    C13---C12---C4             109.7 (2)
  C6---C5---C4            117.95 (12)    C11---C12---C4             110.08 (12)
  C6---C5---C9            118.74 (11)    C14B---C12---C13B          113.2 (7)
  C4---C5---C9            123.29 (12)    C4---C12---C13B            108.6 (7)
  C7---C6---C5            124.45 (11)    C13---C12---C14            107.86 (18)
  C7---C6---H4            117.8          C11---C12---C14            106.67 (13)
  C5---C6---H4            117.8          C4---C12---C14             109.60 (12)
  C6---C7---C2            116.93 (11)    C13B---C12---C14           96.1 (6)
  C6---C7---C8            119.00 (12)    C14B---C12---C11B          114.1 (4)
  C2---C7---C8            124.04 (12)    C13---C12---C11B           85.8 (2)
  C7---C8---H1            109.5          C4---C12---C11B            106.7 (2)
  C7---C8---H2            109.5          C13B---C12---C11B          99.1 (6)
  H1---C8---H2            109.5          C14---C12---C11B           133.4 (2)
  C7---C8---H3            109.5          C12---C13---H5             109.5
  H1---C8---H3            109.5          C12---C13---H6             109.5
  H2---C8---H3            109.5          C12---C13---H7             109.5
  C10B---C9---C16         125.2 (4)      C12---C14---H8             109.5
  C10B---C9---C17         86.8 (3)       C12---C14---H9             109.5
  C16---C9---C17          109.67 (19)    C12---C14---H10            109.5
  C10B---C9---C5          112.5 (2)      C9---C16---H17             109.5
  C16---C9---C5           110.8 (3)      C9---C16---H18             109.5
  C17---C9---C5           108.32 (14)    C9---C16---H19             109.5
  C10B---C9---C17B        105.9 (4)      C9---C17---H20             109.5
  C16---C9---C17B         91.1 (4)       C9---C17---H21             109.5
  C5---C9---C17B          107.8 (4)      C9---C17---H22             109.5
  C10B---C9---C16B        118.5 (10)     C12---C13B---H5B           109.5
  C17---C9---C16B         124.8 (6)      C12---C13B---H6B           109.5
  C5---C9---C16B          105.2 (9)      H5B---C13B---H6B           109.5
  C17B---C9---C16B        106.5 (7)      C12---C13B---H7B           109.5
  C17---C9---C10          111.94 (15)    H5B---C13B---H7B           109.5
  C5---C9---C10           109.60 (12)    H6B---C13B---H7B           109.5
  C17B---C9---C10         128.9 (4)      C12---C14B---H8B           109.5
  C16B---C9---C10         95.9 (9)       C12---C14B---H9B           109.5
  C11---C10---C15         110.1 (2)      H8B---C14B---H9B           109.5
  C11---C10---C9          110.65 (14)    C12---C14B---H10B          109.5
  C15---C10---C9          113.8 (2)      H8B---C14B---H10B          109.5
  C11---C10---H16         107.3          H9B---C14B---H10B          109.5
  C15---C10---H16         107.3          C9---C16B---H17B           109.5
  C9---C10---H16          107.3          C9---C16B---H18B           109.5
  C12---C11---C10         112.30 (14)    H17B---C16B---H18B         109.5
  C12---C11---H11         109.1          C9---C16B---H19B           109.5
  C10---C11---H11         109.1          H17B---C16B---H19B         109.5
  C12---C11---H12         109.1          H18B---C16B---H19B         109.5
  C10---C11---H12         109.1          C9---C17B---H20B           109.5
  H11---C11---H12         107.9          C9---C17B---H21B           109.5
  C11B---C10B---C15B      112.3 (8)      H20B---C17B---H21B         109.5
  C11B---C10B---C9        109.3 (4)      C9---C17B---H22B           109.5
  C15B---C10B---C9        116.5 (9)      H20B---C17B---H22B         109.5
  C11B---C10B---H16B      106.0          H21B---C17B---H22B         109.5
  C15B---C10B---H16B      106.0          O1---C18---H24             109.5
  C9---C10B---H16B        106.0          O1---C18---H25             109.5
  C10B---C11B---C12       112.4 (4)      H24---C18---H25            109.5
  C10B---C11B---H11B      109.1          O1---C18---H26             109.5
  C12---C11B---H11B       109.1          H24---C18---H26            109.5
  C10B---C11B---H12B      109.1          H25---C18---H26            109.5
                                                                    
  C18---O1---C1---O2      1.2 (2)        C17B---C9---C10---C15      36.1 (5)
  C18---O1---C1---C2      179.86 (13)    C16B---C9---C10---C15      −80.7 (8)
  O2---C1---C2---C3       169.86 (15)    C15---C10---C11---C12      167.6 (2)
  O1---C1---C2---C3       −8.72 (18)     C9---C10---C11---C12       −65.6 (2)
  O2---C1---C2---C7       −10.8 (2)      C16---C9---C10B---C11B     94.2 (5)
  O1---C1---C2---C7       170.60 (11)    C17---C9---C10B---C11B     −153.9 (4)
  C7---C2---C3---C4       0.10 (18)      C5---C9---C10B---C11B      −45.4 (5)
  C1---C2---C3---C4       179.43 (11)    C17B---C9---C10B---C11B    −162.8 (5)
  C2---C3---C4---C5       0.59 (18)      C16B---C9---C10B---C11B    77.8 (9)
  C2---C3---C4---C12      179.94 (11)    C10---C9---C10B---C11B     43.7 (4)
  C3---C4---C5---C6       −0.56 (17)     C16---C9---C10B---C15B     −34.4 (8)
  C12---C4---C5---C6      −179.88 (11)   C17---C9---C10B---C15B     77.5 (7)
  C3---C4---C5---C9       −178.83 (11)   C5---C9---C10B---C15B      −174.0 (6)
  C12---C4---C5---C9      1.85 (18)      C17B---C9---C10B---C15B    68.5 (8)
  C4---C5---C6---C7       −0.15 (19)     C16B---C9---C10B---C15B    −50.9 (10)
  C9---C5---C6---C7       178.20 (11)    C10---C9---C10B---C15B     −85.0 (8)
  C5---C6---C7---C2       0.83 (19)      C15B---C10B---C11B---C12   −161.7 (8)
  C5---C6---C7---C8       −177.28 (12)   C9---C10B---C11B---C12     67.4 (5)
  C3---C2---C7---C6       −0.78 (17)     C10---C11---C12---C14B     162.2 (4)
  C1---C2---C7---C6       179.90 (11)    C10---C11---C12---C13      −74.5 (3)
  C3---C2---C7---C8       177.23 (12)    C10---C11---C12---C4       48.37 (18)
  C1---C2---C7---C8       −2.10 (19)     C10---C11---C12---C13B     −83.0 (8)
  C6---C5---C9---C10B     −166.3 (3)     C10---C11---C12---C14      167.20 (16)
  C4---C5---C9---C10B     12.0 (3)       C10---C11---C12---C11B     −41.0 (4)
  C6---C5---C9---C16      48.2 (2)       C3---C4---C12---C14B       69.9 (3)
  C4---C5---C9---C16      −133.5 (2)     C5---C4---C12---C14B       −110.8 (3)
  C6---C5---C9---C17      −72.09 (16)    C3---C4---C12---C13        −71.72 (18)
  C4---C5---C9---C17      106.17 (16)    C5---C4---C12---C13        107.60 (17)
  C6---C5---C9---C17B     −50.0 (3)      C3---C4---C12---C11        163.56 (12)
  C4---C5---C9---C17B     128.3 (3)      C5---C4---C12---C11        −17.12 (17)
  C6---C5---C9---C16B     63.4 (8)       C3---C4---C12---C13B       −57.3 (6)
  C4---C5---C9---C16B     −118.4 (8)     C5---C4---C12---C13B       122.0 (6)
  C6---C5---C9---C10      165.52 (12)    C3---C4---C12---C14        46.53 (17)
  C4---C5---C9---C10      −16.23 (17)    C5---C4---C12---C14        −134.15 (14)
  C16---C9---C10---C11    166.1 (2)      C3---C4---C12---C11B       −163.2 (2)
  C17---C9---C10---C11    −74.04 (19)    C5---C4---C12---C11B       16.1 (3)
  C5---C9---C10---C11     46.17 (18)     C10B---C11B---C12---C14B   75.9 (6)
  C17B---C9---C10---C11   −88.6 (5)      C10B---C11B---C12---C13    −160.2 (5)
  C16B---C9---C10---C11   154.6 (7)      C10B---C11B---C12---C11    50.5 (4)
  C16---C9---C10---C15    −69.3 (3)      C10B---C11B---C12---C4     −50.9 (5)
  C17---C9---C10---C15    50.6 (2)       C10B---C11B---C12---C13B   −163.5 (8)
  C5---C9---C10---C15     170.84 (18)    C10B---C11B---C12---C14    89.0 (5)
  ----------------------- -------------- -------------------------- --------------

Hydrogen-bond geometry (Å, °) {#tablewraphbondslong}
=============================

  ------------------- --------- --------- ------------- ---------------
  *D*---H···*A*       *D*---H   H···*A*   *D*···*A*     *D*---H···*A*
  C3---H23···O1       0.95      2.32      2.6839 (17)   103
  C18---H26···O2^i^   0.98      2.47      3.397 (2)     157
  ------------------- --------- --------- ------------- ---------------

Symmetry codes: (i) −*x*+1, −*y*+3, −*z*.

###### Hydrogen-bond geometry (Å, °)

  *D*---H⋯*A*       *D*---H   H⋯*A*   *D*⋯*A*     *D*---H⋯*A*
  ----------------- --------- ------- ----------- -------------
  C18---H26⋯O2^i^   0.98      2.47    3.397 (2)   157

Symmetry code: (i) .
