Diverging Pathways to Topologically Complex Polycyclic Bis-acetals and Their Ring System Interchange.
Castillo, Rafael R.; Aquino, Maurizio; Gandara, Zoila; Safir, Imad; Elkhayat, Zobida; Retailleau, Pascal; Arseniyadis, Siméon; Organic letters 14 (2012) 1628–1631; doi:10.1021/ol300388b

data_1507193
_publ_section_title
;
 Diverging Pathways to Topologically Complex Polycyclic Bis-acetals and
 Their Ring System Interchange.
;
_journal_issue                   6
_journal_name_full               'Organic letters'
_journal_page_first              1628
_journal_page_last               1631
_journal_paper_doi               10.1021/ol300388b
_journal_volume                  14
_journal_year                    2012
_chemical_formula_moiety         'C20 H24 O6'
_chemical_formula_sum            'C20 H24 O6'
_chemical_formula_weight         360.39
_chemical_name_systematic
; 
 rac-(2R,5aR,9aS)-9a-((S)-benzo[d][1,3]dioxol-5-yl
(methoxymethoxy)methyl)-2,6,7,8,9,9a-hexahydro-1H-2,5a-
epoxybenzo[d]oxepine 
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 133.278(9)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.3489(8)
_cell_length_b                   15.4961(8)
_cell_length_c                   12.4019(8)
_cell_measurement_reflns_used    2686
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      72.0
_cell_measurement_theta_min      6.9
_cell_volume                     1727.8(3)
_computing_cell_refinement       'CrystalClear-SM Expert 2.0 r4 (Rigaku, 2009)'
_computing_data_collection       'CrystalClear-SM Expert 2.0 r4 (Rigaku, 2009)'
_computing_data_reduction        'CrystalClear-SM Expert 2.0 r4 (Rigaku, 2009)'
_computing_molecular_graphics    'PLATON (Spek, 2003)'
_computing_publication_material  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_refinement
'SHELXL97 (Sheldrick, 2008); CRYSTALBUILDER (Welter, 2006)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      293(2)
_diffrn_detector_type
'RAPID II large area curved imaging plate detector '
_diffrn_measured_fraction_theta_full 0.986
_diffrn_measured_fraction_theta_max 0.987
_diffrn_measurement_device_type  'Rigaku rapid II RAXIS conversion'
_diffrn_measurement_method       'profile data from \w-scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54187
_diffrn_reflns_av_R_equivalents  0.0449
_diffrn_reflns_av_sigmaI/netI    0.0448
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            12620
_diffrn_reflns_theta_full        68.24
_diffrn_reflns_theta_max         68.24
_diffrn_reflns_theta_min         6.92
_exptl_absorpt_coefficient_mu    0.842
_exptl_absorpt_correction_T_max  1.000
_exptl_absorpt_correction_T_min  0.764
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'FS_ABSCOR (Rigaku, 2009)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.385
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             768
_exptl_crystal_size_max          0.43
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.38
_refine_diff_density_max         0.228
_refine_diff_density_min         -0.241
_refine_diff_density_rms         0.047
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.142
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     236
_refine_ls_number_reflns         3115
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.142
_refine_ls_R_factor_all          0.0543
_refine_ls_R_factor_gt           0.0418
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0667P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1127
_refine_ls_wR_factor_ref         0.1278
_reflns_number_gt                2406
_reflns_number_total             3115
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol300388b_si_003.cif
_cod_data_source_block           compound_2e_C11S
_cod_original_cell_volume        1727.8(2)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               1507193