A systematic study of functionalized oxiranes as initiating groups for cationic polycyclization reactions.
Rajendar, Goreti; Corey, E. J.; Journal of the American Chemical Society 137 (2015) 5837–5844; doi:10.1021/jacs.5b03229

data_4129432
_publ_section_title
;
 A systematic study of functionalized oxiranes as initiating groups for
 cationic polycyclization reactions.
;
_journal_issue                   17
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              5837
_journal_page_last               5844
_journal_paper_doi               10.1021/jacs.5b03229
_journal_volume                  137
_journal_year                    2015
_chemical_absolute_configuration ad
_chemical_formula_sum            'C24 H28 O2'
_chemical_formula_weight         348.46
_space_group_crystal_system      monoclinic
_space_group_IT_number           4
_space_group_name_Hall           'P 2yb'
_space_group_name_H-M_alt        'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014/6
_cell_angle_alpha                90
_cell_angle_beta                 110.6862(18)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   17.6439(5)
_cell_length_b                   5.9607(2)
_cell_length_c                   18.9000(5)
_cell_measurement_reflns_used    9215
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      66.5
_cell_measurement_theta_min      2.68
_cell_volume                     1859.56(10)
_computing_cell_refinement       'SAINT 8.34C (Bruker-AXS, 2014)'
_computing_data_collection       'APEX2 v2014.3.0 (Bruker-AXS, 2014)'
_computing_data_reduction        'SAINT 8.34C (Bruker-AXS, 2014)'
_computing_molecular_graphics    'Bruker SHELXTL (Sheldrick, 2008)'
_computing_publication_material  'Bruker SHELXTL (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL-2014 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXT-2014 (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.970
_diffrn_measured_fraction_theta_max 0.990
_diffrn_measurement_device_type
;
Bruker D8 goniometer with CCD area detector  
;
_diffrn_measurement_method       'omega and phi scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'I\mS microfocus tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0571
_diffrn_reflns_av_unetI/netI     0.0345
_diffrn_reflns_Laue_measured_fraction_full 0.970
_diffrn_reflns_Laue_measured_fraction_max 0.990
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -21
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            46891
_diffrn_reflns_point_group_measured_fraction_full 0.922
_diffrn_reflns_point_group_measured_fraction_max 0.942
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         66.684
_diffrn_reflns_theta_min         2.499
_exptl_absorpt_coefficient_mu    0.599
_exptl_absorpt_correction_T_max  0.8642
_exptl_absorpt_correction_T_min  0.7845
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            Colorless
_exptl_crystal_density_diffrn    1.245
_exptl_crystal_description       plate
_exptl_crystal_F_000             752
_exptl_crystal_size_max          0.180
_exptl_crystal_size_mid          0.160
_exptl_crystal_size_min          0.010
_refine_diff_density_max         0.300
_refine_diff_density_min         -0.212
_refine_diff_density_rms         0.035
_refine_ls_abs_structure_details
;
 Flack x determined using 2013 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   -0.5(3)
_refine_ls_extinction_coef       0.0016(2)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.052
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     594
_refine_ls_number_reflns         6196
_refine_ls_number_restraints     103
_refine_ls_restrained_S_all      1.051
_refine_ls_R_factor_all          0.0529
_refine_ls_R_factor_gt           0.0449
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0452P)^2^+0.6182P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1088
_refine_ls_wR_factor_ref         0.1126
_reflns_Friedel_coverage         0.722
_reflns_Friedel_fraction_full    0.864
_reflns_Friedel_fraction_max     0.882
_reflns_number_gt                5328
_reflns_number_total             6196
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja5b03229_si_003.cif
_cod_data_source_block           GR-Be
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               4129432
_shelx_estimated_absorpt_t_min   0.900
_shelx_estimated_absorpt_t_max   0.994
_shelxl_version_number           2014/6
_shelx_res_checksum              12850
_shelx_hkl_checksum              28780