# Electronic Supplementary Material (ESI) for Chemical Communications # This journal is © The Royal Society of Chemistry 2013 ####################################################################### # # Cambridge Crystallographic Data Centre # CCDC # ####################################################################### # # This CIF contains data from an original supplementary publication # deposited with the CCDC, and may include chemical, crystal, # experimental, refinement, atomic coordinates, # anisotropic displacement parameters and molecular geometry data, # as required by the journal to which it was submitted. # # This CIF is provided on the understanding that it is used for bona # fide research purposes only. It may contain copyright material # of the CCDC or of third parties, and may not be copied or further # disseminated in any form, whether machine-readable or not, # except for the purpose of generating routine backup copies # on your local computer system. # # For further information on the CCDC, data deposition and # data retrieval see: # www.ccdc.cam.ac.uk # # Bona fide researchers may freely download Mercury and enCIFer # from this site to visualise CIF-encoded structures and # to carry out CIF format checking respectively. # data_a _audit_creation_method SHELXL-97 _chemical_name_systematic ; ? ; _chemical_name_common ? _chemical_melting_point ? _chemical_formula_moiety ? _chemical_formula_sum 'C21 H36 O3 Si' _chemical_formula_weight 364.59 loop_ _atom_type_symbol _atom_type_description _atom_type_scat_dispersion_real _atom_type_scat_dispersion_imag _atom_type_scat_source C C 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' O O 0.0106 0.0060 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' Si Si 0.0817 0.0704 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4' _symmetry_cell_setting monoclinic _symmetry_space_group_name_H-M P2(1)/c loop_ _symmetry_equiv_pos_as_xyz 'x, y, z' '-x, y+1/2, -z+1/2' '-x, -y, -z' 'x, -y-1/2, z-1/2' _cell_length_a 12.483(3) _cell_length_b 15.134(3) _cell_length_c 11.714(2) _cell_angle_alpha 90.00 _cell_angle_beta 93.92(3) _cell_angle_gamma 90.00 _cell_volume 2207.8(8) _cell_formula_units_Z 4 _cell_measurement_temperature 293(2) _cell_measurement_reflns_used ? _cell_measurement_theta_min 1.64 _cell_measurement_theta_max 27.48 _exptl_crystal_description ? _exptl_crystal_colour ? _exptl_crystal_size_max 0.30 _exptl_crystal_size_mid 0.30 _exptl_crystal_size_min 0.20 _exptl_crystal_density_meas ? _exptl_crystal_density_diffrn 1.097 _exptl_crystal_density_method 'not measured' _exptl_crystal_F_000 800 _exptl_absorpt_coefficient_mu 0.122 _exptl_absorpt_correction_type Empirical _exptl_absorpt_correction_T_min 0.9644 _exptl_absorpt_correction_T_max 0.9761 _exptl_absorpt_process_details ; HIGASHI, T. (1995). Abscor-Empirical Absorption Correction based on Fourier Series Approximation. Rigaku Corporation,Tokyo,Japan. ; _diffrn_ambient_temperature 293(2) _diffrn_radiation_wavelength 0.71073 _diffrn_radiation_type MoK\a _diffrn_radiation_source 'fine-focus sealed tube' _diffrn_radiation_monochromator graphite _diffrn_measurement_device_type 'Rigaku RAXIS RAPID IP' _diffrn_measurement_method \W _diffrn_detector_area_resol_mean 10.00 _diffrn_standards_number 0 _diffrn_standards_interval_count 0 _diffrn_standards_interval_time 0 _diffrn_standards_decay_% 0 _diffrn_reflns_number 7914 _diffrn_reflns_av_R_equivalents 0.0613 _diffrn_reflns_av_sigmaI/netI 0.1725 _diffrn_reflns_limit_h_min -16 _diffrn_reflns_limit_h_max 16 _diffrn_reflns_limit_k_min -19 _diffrn_reflns_limit_k_max 19 _diffrn_reflns_limit_l_min -14 _diffrn_reflns_limit_l_max 15 _diffrn_reflns_theta_min 1.64 _diffrn_reflns_theta_max 27.48 _reflns_number_total 4868 _reflns_number_gt 1641 _reflns_threshold_expression >2sigma(I) _computing_data_collection 'Rapid-AUTO (Rigaku,2000)' _computing_cell_refinement Rapid-AUTO _computing_data_reduction 'CrystalStructure (Rigaku/MSC,2000)' _computing_structure_solution SHELXS-97,(Sheldrick,1997) _computing_structure_refinement SHELXL-97,(Sheldrick,1997) _computing_molecular_graphics 'Siemens SHELXTL V4.2,(Sheldrick,1990)' _computing_publication_material SHELXL-97,(Sheldrick,1997) _refine_special_details ; 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. ; _refine_ls_structure_factor_coef Fsqd _refine_ls_matrix_type full _refine_ls_weighting_scheme calc _refine_ls_weighting_details 'calc w=1/[\s^2^(Fo^2^)+(0.2000P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3' _atom_sites_solution_primary direct _atom_sites_solution_secondary difmap _atom_sites_solution_hydrogens geom _refine_ls_hydrogen_treatment none _refine_ls_extinction_method SHELXL _refine_ls_extinction_coef 0.053(10) _refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^ _refine_ls_number_reflns 4868 _refine_ls_number_parameters 236 _refine_ls_number_restraints 3 _refine_ls_R_factor_all 0.2563 _refine_ls_R_factor_gt 0.1366 _refine_ls_wR_factor_ref 0.4341 _refine_ls_wR_factor_gt 0.3827 _refine_ls_goodness_of_fit_ref 1.126 _refine_ls_restrained_S_all 1.142 _refine_ls_shift/su_max 0.001 _refine_ls_shift/su_mean 0.000 loop_ _atom_site_label _atom_site_type_symbol _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_U_iso_or_equiv _atom_site_adp_type _atom_site_occupancy _atom_site_symmetry_multiplicity _atom_site_calc_flag _atom_site_refinement_flags _atom_site_disorder_assembly _atom_site_disorder_group C21 C 0.4127(7) 0.0677(7) 0.2752(9) 0.145(5) Uani 1 1 d D . . H21A H 0.4310 0.0172 0.3220 0.217 Uiso 1 1 calc R . . H21B H 0.4063 0.0503 0.1962 0.217 Uiso 1 1 calc R . . H21C H 0.3456 0.0917 0.2961 0.217 Uiso 1 1 calc R . . C1 C 0.8209(5) 0.4319(5) 0.3492(6) 0.0560(18) Uani 1 1 d . . . C2 C 0.7750(5) 0.3449(4) 0.3259(6) 0.0558(19) Uani 1 1 d . . . H2 H 0.7295 0.3160 0.3733 0.067 Uiso 1 1 calc R . . C3 C 0.8061(4) 0.3118(4) 0.2284(6) 0.0475(16) Uani 1 1 d . . . C4 C 0.7813(4) 0.2242(4) 0.1755(6) 0.0455(16) Uani 1 1 d . . . H4 H 0.7421 0.2335 0.1012 0.055 Uiso 1 1 calc R . . C5 C 0.8862(4) 0.1774(4) 0.1565(6) 0.0495(17) Uani 1 1 d . . . H5A H 0.8709 0.1225 0.1159 0.059 Uiso 1 1 calc R . . H5B H 0.9225 0.1630 0.2300 0.059 Uiso 1 1 calc R . . C6 C 0.9608(4) 0.2345(4) 0.0876(5) 0.0442(16) Uani 1 1 d . . . H6 H 0.9228 0.2463 0.0131 0.053 Uiso 1 1 calc R . . C7 C 1.0641(4) 0.1857(4) 0.0647(6) 0.0509(17) Uani 1 1 d . . . H7 H 1.1008 0.1698 0.1384 0.061 Uiso 1 1 calc R . . C8 C 1.1402(5) 0.2404(4) -0.0017(7) 0.0612(19) Uani 1 1 d . . . H8 H 1.1023 0.2549 -0.0753 0.073 Uiso 1 1 calc R . . C9 C 1.1646(5) 0.3266(5) 0.0596(8) 0.073(2) Uani 1 1 d . . . H9A H 1.2105 0.3622 0.0145 0.087 Uiso 1 1 calc R . . H9B H 1.2034 0.3145 0.1325 0.087 Uiso 1 1 calc R . . C10 C 1.0623(5) 0.3791(5) 0.0805(6) 0.064(2) Uani 1 1 d . . . H10A H 1.0817 0.4320 0.1239 0.076 Uiso 1 1 calc R . . H10B H 1.0278 0.3973 0.0075 0.076 Uiso 1 1 calc R . . C11 C 0.9833(4) 0.3246(4) 0.1457(6) 0.0462(16) Uani 1 1 d . . . H11 H 1.0197 0.3117 0.2207 0.055 Uiso 1 1 calc R . . C12 C 0.8803(5) 0.3736(4) 0.1694(5) 0.0466(16) Uani 1 1 d . . . C13 C 0.8202(5) 0.4096(4) 0.0565(6) 0.065(2) Uani 1 1 d . . . H13A H 0.8582 0.4598 0.0295 0.097 Uiso 1 1 calc R . . H13B H 0.7486 0.4268 0.0719 0.097 Uiso 1 1 calc R . . H13C H 0.8173 0.3641 -0.0008 0.097 Uiso 1 1 calc R . . C14 C 0.8988(5) 0.4488(4) 0.2563(6) 0.061(2) Uani 1 1 d . . . H14A H 0.9724 0.4484 0.2887 0.073 Uiso 1 1 calc R . . H14B H 0.8843 0.5056 0.2200 0.073 Uiso 1 1 calc R . . C15 C 1.2415(6) 0.1919(6) -0.0275(9) 0.103(3) Uani 1 1 d . . . H15A H 1.2775 0.1716 0.0427 0.155 Uiso 1 1 calc R . . H15B H 1.2879 0.2310 -0.0656 0.155 Uiso 1 1 calc R . . H15C H 1.2234 0.1422 -0.0760 0.155 Uiso 1 1 calc R . . O1 O 0.8043(4) 0.4813(3) 0.4285(5) 0.0686(16) Uani 1 1 d . . . O2 O 0.7148(3) 0.1748(3) 0.2468(4) 0.0583(14) Uani 1 1 d . . . O3 O 1.0348(4) 0.1056(3) 0.0040(5) 0.0708(16) Uani 1 1 d . . . H3 H 1.0826 0.0688 0.0154 0.106 Uiso 1 1 calc R . . Si1 Si 0.6099(2) 0.1160(3) 0.2128(2) 0.1389(17) Uani 1 1 d . . . C20 C 0.5348(7) 0.1336(7) 0.4251(7) 0.110(3) Uani 1 1 d D . . H20A H 0.4717 0.1410 0.4667 0.165 Uiso 1 1 calc R . . H20B H 0.5857 0.1791 0.4468 0.165 Uiso 1 1 calc R . . H20C H 0.5661 0.0768 0.4423 0.165 Uiso 1 1 calc R . . C19 C 0.4806(11) 0.2411(8) 0.2446(12) 0.158(6) Uani 1 1 d D . . H19A H 0.5172 0.2829 0.2950 0.238 Uiso 1 1 calc R . . H19B H 0.4048 0.2528 0.2407 0.238 Uiso 1 1 calc R . . H19C H 0.5064 0.2463 0.1696 0.238 Uiso 1 1 calc R . . C18 C 0.5034(8) 0.1400(9) 0.2936(8) 0.189(8) Uani 1 1 d D . . C17 C 0.6528(10) -0.0100(6) 0.2735(12) 0.173(6) Uani 1 1 d . . . H17A H 0.7295 -0.0159 0.2774 0.260 Uiso 1 1 calc R . . H17B H 0.6209 -0.0538 0.2226 0.260 Uiso 1 1 calc R . . H17C H 0.6275 -0.0179 0.3484 0.260 Uiso 1 1 calc R . . C16 C 0.5761(6) 0.1103(5) 0.0577(7) 0.088(3) Uani 1 1 d . . . H16A H 0.5715 0.1691 0.0268 0.132 Uiso 1 1 calc R . . H16B H 0.5083 0.0810 0.0434 0.132 Uiso 1 1 calc R . . H16C H 0.6308 0.0780 0.0219 0.132 Uiso 1 1 calc R . . loop_ _atom_site_aniso_label _atom_site_aniso_U_11 _atom_site_aniso_U_22 _atom_site_aniso_U_33 _atom_site_aniso_U_23 _atom_site_aniso_U_13 _atom_site_aniso_U_12 C21 0.078(6) 0.260(15) 0.097(9) 0.010(9) 0.011(6) -0.090(8) C1 0.055(4) 0.056(5) 0.058(5) 0.001(4) 0.003(3) 0.003(3) C2 0.055(4) 0.054(4) 0.059(5) 0.006(4) 0.013(3) -0.012(3) C3 0.039(3) 0.055(4) 0.048(4) 0.008(3) 0.003(3) -0.005(3) C4 0.047(3) 0.042(4) 0.049(4) -0.001(3) 0.009(3) -0.016(3) C5 0.050(4) 0.039(4) 0.060(5) -0.002(3) 0.007(3) -0.007(3) C6 0.038(3) 0.046(4) 0.049(4) 0.011(3) 0.003(3) -0.005(3) C7 0.043(3) 0.051(4) 0.058(5) 0.003(3) 0.000(3) -0.002(3) C8 0.054(4) 0.063(5) 0.068(5) -0.001(4) 0.010(3) -0.003(3) C9 0.055(4) 0.074(5) 0.091(6) 0.001(4) 0.017(4) -0.022(4) C10 0.055(4) 0.065(5) 0.071(6) 0.002(4) 0.011(4) -0.015(3) C11 0.049(3) 0.041(4) 0.049(4) 0.006(3) 0.003(3) -0.012(3) C12 0.048(3) 0.044(4) 0.048(4) -0.002(3) 0.005(3) -0.002(3) C13 0.063(4) 0.060(5) 0.071(5) 0.015(4) -0.002(4) 0.008(3) C14 0.065(4) 0.046(4) 0.072(6) -0.007(3) 0.007(4) -0.013(3) C15 0.066(5) 0.089(6) 0.160(11) -0.003(6) 0.045(6) -0.002(5) O1 0.070(3) 0.059(3) 0.078(4) -0.021(3) 0.011(3) 0.002(2) O2 0.054(3) 0.056(3) 0.066(4) -0.001(2) 0.013(2) -0.017(2) O3 0.053(3) 0.059(3) 0.099(4) -0.014(3) -0.002(3) 0.006(2) Si1 0.111(2) 0.245(4) 0.063(2) -0.034(2) 0.0258(15) -0.120(2) C20 0.086(6) 0.176(10) 0.070(7) -0.005(7) 0.017(5) -0.006(6) C19 0.188(12) 0.133(10) 0.148(12) -0.024(8) -0.031(10) 0.098(9) C18 0.100(8) 0.40(2) 0.068(8) -0.055(11) 0.033(6) -0.157(12) C17 0.209(13) 0.047(6) 0.253(17) 0.025(8) -0.064(12) 0.007(7) C16 0.095(6) 0.104(7) 0.067(6) -0.019(5) 0.017(5) -0.038(5) _geom_special_details ; 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. ; loop_ _geom_bond_atom_site_label_1 _geom_bond_atom_site_label_2 _geom_bond_distance _geom_bond_site_symmetry_2 _geom_bond_publ_flag C21 C18 1.578(8) . ? C21 H21A 0.9600 . ? C21 H21B 0.9600 . ? C21 H21C 0.9600 . ? C1 O1 1.221(8) . ? C1 C2 1.455(9) . ? C1 C14 1.530(10) . ? C2 C3 1.329(9) . ? C2 H2 0.9300 . ? C3 C4 1.486(8) . ? C3 C12 1.516(8) . ? C4 O2 1.428(6) . ? C4 C5 1.519(8) . ? C4 H4 0.9800 . ? C5 C6 1.539(8) . ? C5 H5A 0.9700 . ? C5 H5B 0.9700 . ? C6 C7 1.525(8) . ? C6 C11 1.541(8) . ? C6 H6 0.9800 . ? C7 O3 1.440(7) . ? C7 C8 1.514(9) . ? C7 H7 0.9800 . ? C8 C15 1.510(9) . ? C8 C9 1.511(9) . ? C8 H8 0.9800 . ? C9 C10 1.537(9) . ? C9 H9A 0.9700 . ? C9 H9B 0.9700 . ? C10 C11 1.531(8) . ? C10 H10A 0.9700 . ? C10 H10B 0.9700 . ? C11 C12 1.526(8) . ? C11 H11 0.9800 . ? C12 C14 1.533(8) . ? C12 C13 1.572(9) . ? C13 H13A 0.9600 . ? C13 H13B 0.9600 . ? C13 H13C 0.9600 . ? C14 H14A 0.9700 . ? C14 H14B 0.9700 . ? C15 H15A 0.9600 . ? C15 H15B 0.9600 . ? C15 H15C 0.9600 . ? O2 Si1 1.611(5) . ? O3 H3 0.8200 . ? Si1 C18 1.723(11) . ? Si1 C16 1.839(8) . ? Si1 C17 2.091(10) . ? C20 C18 1.567(8) . ? C20 H20A 0.9600 . ? C20 H20B 0.9600 . ? C20 H20C 0.9600 . ? C19 C18 1.652(9) . ? C19 H19A 0.9600 . ? C19 H19B 0.9600 . ? C19 H19C 0.9600 . ? C17 H17A 0.9600 . ? C17 H17B 0.9600 . ? C17 H17C 0.9600 . ? C16 H16A 0.9600 . ? C16 H16B 0.9600 . ? C16 H16C 0.9600 . ? loop_ _geom_angle_atom_site_label_1 _geom_angle_atom_site_label_2 _geom_angle_atom_site_label_3 _geom_angle _geom_angle_site_symmetry_1 _geom_angle_site_symmetry_3 _geom_angle_publ_flag C18 C21 H21A 109.5 . . ? C18 C21 H21B 109.5 . . ? H21A C21 H21B 109.5 . . ? C18 C21 H21C 109.5 . . ? H21A C21 H21C 109.5 . . ? H21B C21 H21C 109.5 . . ? O1 C1 C2 127.8(7) . . ? O1 C1 C14 126.0(6) . . ? C2 C1 C14 106.2(6) . . ? C3 C2 C1 111.6(6) . . ? C3 C2 H2 124.2 . . ? C1 C2 H2 124.2 . . ? C2 C3 C4 129.0(6) . . ? C2 C3 C12 112.5(6) . . ? C4 C3 C12 118.5(6) . . ? O2 C4 C3 109.7(5) . . ? O2 C4 C5 112.5(5) . . ? C3 C4 C5 108.6(5) . . ? O2 C4 H4 108.6 . . ? C3 C4 H4 108.6 . . ? C5 C4 H4 108.6 . . ? C4 C5 C6 112.0(5) . . ? C4 C5 H5A 109.2 . . ? C6 C5 H5A 109.2 . . ? C4 C5 H5B 109.2 . . ? C6 C5 H5B 109.2 . . ? H5A C5 H5B 107.9 . . ? C7 C6 C5 111.7(5) . . ? C7 C6 C11 112.0(4) . . ? C5 C6 C11 111.3(5) . . ? C7 C6 H6 107.2 . . ? C5 C6 H6 107.2 . . ? C11 C6 H6 107.2 . . ? O3 C7 C8 110.7(6) . . ? O3 C7 C6 107.8(4) . . ? C8 C7 C6 113.2(5) . . ? O3 C7 H7 108.4 . . ? C8 C7 H7 108.4 . . ? C6 C7 H7 108.4 . . ? C15 C8 C9 111.8(6) . . ? C15 C8 C7 113.6(6) . . ? C9 C8 C7 109.9(6) . . ? C15 C8 H8 107.0 . . ? C9 C8 H8 107.0 . . ? C7 C8 H8 107.0 . . ? C8 C9 C10 112.3(5) . . ? C8 C9 H9A 109.1 . . ? C10 C9 H9A 109.1 . . ? C8 C9 H9B 109.1 . . ? C10 C9 H9B 109.1 . . ? H9A C9 H9B 107.9 . . ? C11 C10 C9 111.8(6) . . ? C11 C10 H10A 109.3 . . ? C9 C10 H10A 109.3 . . ? C11 C10 H10B 109.3 . . ? C9 C10 H10B 109.3 . . ? H10A C10 H10B 107.9 . . ? C12 C11 C10 114.1(5) . . ? C12 C11 C6 112.3(4) . . ? C10 C11 C6 111.1(5) . . ? C12 C11 H11 106.2 . . ? C10 C11 H11 106.2 . . ? C6 C11 H11 106.2 . . ? C3 C12 C11 109.3(5) . . ? C3 C12 C14 103.0(5) . . ? C11 C12 C14 113.0(5) . . ? C3 C12 C13 109.0(5) . . ? C11 C12 C13 112.0(5) . . ? C14 C12 C13 110.1(5) . . ? C12 C13 H13A 109.5 . . ? C12 C13 H13B 109.5 . . ? H13A C13 H13B 109.5 . . ? C12 C13 H13C 109.5 . . ? H13A C13 H13C 109.5 . . ? H13B C13 H13C 109.5 . . ? C1 C14 C12 105.9(5) . . ? C1 C14 H14A 110.6 . . ? C12 C14 H14A 110.6 . . ? C1 C14 H14B 110.6 . . ? C12 C14 H14B 110.6 . . ? H14A C14 H14B 108.7 . . ? C8 C15 H15A 109.5 . . ? C8 C15 H15B 109.5 . . ? H15A C15 H15B 109.5 . . ? C8 C15 H15C 109.5 . . ? H15A C15 H15C 109.5 . . ? H15B C15 H15C 109.5 . . ? C4 O2 Si1 129.8(4) . . ? C7 O3 H3 109.5 . . ? O2 Si1 C18 113.1(4) . . ? O2 Si1 C16 113.4(3) . . ? C18 Si1 C16 114.8(4) . . ? O2 Si1 C17 103.6(4) . . ? C18 Si1 C17 101.2(6) . . ? C16 Si1 C17 109.3(5) . . ? C18 C20 H20A 109.5 . . ? C18 C20 H20B 109.5 . . ? H20A C20 H20B 109.5 . . ? C18 C20 H20C 109.5 . . ? H20A C20 H20C 109.5 . . ? H20B C20 H20C 109.5 . . ? C18 C19 H19A 109.5 . . ? C18 C19 H19B 109.5 . . ? H19A C19 H19B 109.5 . . ? C18 C19 H19C 109.5 . . ? H19A C19 H19C 109.5 . . ? H19B C19 H19C 109.5 . . ? C20 C18 C21 102.7(7) . . ? C20 C18 C19 115.1(10) . . ? C21 C18 C19 119.3(10) . . ? C20 C18 Si1 112.1(7) . . ? C21 C18 Si1 110.6(8) . . ? C19 C18 Si1 97.2(6) . . ? Si1 C17 H17A 109.5 . . ? Si1 C17 H17B 109.5 . . ? H17A C17 H17B 109.5 . . ? Si1 C17 H17C 109.5 . . ? H17A C17 H17C 109.5 . . ? H17B C17 H17C 109.5 . . ? Si1 C16 H16A 109.5 . . ? Si1 C16 H16B 109.5 . . ? H16A C16 H16B 109.5 . . ? Si1 C16 H16C 109.5 . . ? H16A C16 H16C 109.5 . . ? H16B C16 H16C 109.5 . . ? loop_ _geom_torsion_atom_site_label_1 _geom_torsion_atom_site_label_2 _geom_torsion_atom_site_label_3 _geom_torsion_atom_site_label_4 _geom_torsion _geom_torsion_site_symmetry_1 _geom_torsion_site_symmetry_2 _geom_torsion_site_symmetry_3 _geom_torsion_site_symmetry_4 _geom_torsion_publ_flag O1 C1 C2 C3 176.5(7) . . . . ? C14 C1 C2 C3 -5.8(7) . . . . ? C1 C2 C3 C4 177.6(6) . . . . ? C1 C2 C3 C12 0.0(8) . . . . ? C2 C3 C4 O2 -0.2(9) . . . . ? C12 C3 C4 O2 177.2(5) . . . . ? C2 C3 C4 C5 -123.5(7) . . . . ? C12 C3 C4 C5 53.9(7) . . . . ? O2 C4 C5 C6 -175.5(5) . . . . ? C3 C4 C5 C6 -53.9(7) . . . . ? C4 C5 C6 C7 -177.8(5) . . . . ? C4 C5 C6 C11 56.2(7) . . . . ? C5 C6 C7 O3 58.0(7) . . . . ? C11 C6 C7 O3 -176.4(5) . . . . ? C5 C6 C7 C8 -179.2(6) . . . . ? C11 C6 C7 C8 -53.6(7) . . . . ? O3 C7 C8 C15 -57.4(8) . . . . ? C6 C7 C8 C15 -178.5(6) . . . . ? O3 C7 C8 C9 176.5(5) . . . . ? C6 C7 C8 C9 55.4(7) . . . . ? C15 C8 C9 C10 176.8(7) . . . . ? C7 C8 C9 C10 -56.0(8) . . . . ? C8 C9 C10 C11 55.6(8) . . . . ? C9 C10 C11 C12 179.7(6) . . . . ? C9 C10 C11 C6 -52.0(7) . . . . ? C7 C6 C11 C12 -179.8(5) . . . . ? C5 C6 C11 C12 -53.9(7) . . . . ? C7 C6 C11 C10 51.1(7) . . . . ? C5 C6 C11 C10 176.9(5) . . . . ? C2 C3 C12 C11 126.0(6) . . . . ? C4 C3 C12 C11 -51.8(7) . . . . ? C2 C3 C12 C14 5.6(7) . . . . ? C4 C3 C12 C14 -172.2(5) . . . . ? C2 C3 C12 C13 -111.2(6) . . . . ? C4 C3 C12 C13 70.9(7) . . . . ? C10 C11 C12 C3 177.0(5) . . . . ? C6 C11 C12 C3 49.4(7) . . . . ? C10 C11 C12 C14 -69.0(7) . . . . ? C6 C11 C12 C14 163.4(5) . . . . ? C10 C11 C12 C13 56.0(7) . . . . ? C6 C11 C12 C13 -71.6(6) . . . . ? O1 C1 C14 C12 -173.2(7) . . . . ? C2 C1 C14 C12 8.9(7) . . . . ? C3 C12 C14 C1 -8.6(6) . . . . ? C11 C12 C14 C1 -126.4(6) . . . . ? C13 C12 C14 C1 107.5(6) . . . . ? C3 C4 O2 Si1 136.4(5) . . . . ? C5 C4 O2 Si1 -102.6(6) . . . . ? C4 O2 Si1 C18 -130.7(6) . . . . ? C4 O2 Si1 C16 2.2(7) . . . . ? C4 O2 Si1 C17 120.6(6) . . . . ? O2 Si1 C18 C20 -54.0(9) . . . . ? C16 Si1 C18 C20 173.8(7) . . . . ? C17 Si1 C18 C20 56.2(8) . . . . ? O2 Si1 C18 C21 -168.0(6) . . . . ? C16 Si1 C18 C21 59.7(9) . . . . ? C17 Si1 C18 C21 -57.8(8) . . . . ? O2 Si1 C18 C19 66.9(7) . . . . ? C16 Si1 C18 C19 -65.4(7) . . . . ? C17 Si1 C18 C19 177.1(6) . . . . ? _diffrn_measured_fraction_theta_max 0.961 _diffrn_reflns_theta_full 27.48 _diffrn_measured_fraction_theta_full 0.961 _refine_diff_density_max 1.341 _refine_diff_density_min -1.071 _refine_diff_density_rms 0.122 _database_code_depnum_ccdc_archive 'CCDC 949493'