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_4129431
_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            'C21 H28 O2'
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_space_group_name_Hall           'P 32 2"'
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_cell_angle_gamma                120
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_cell_length_c                   26.1124(5)
_cell_measurement_reflns_used    9950
_cell_measurement_temperature    100(2)
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_cell_measurement_theta_min      4.73
_cell_volume                     2633.01(9)
_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)
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_diffrn_measured_fraction_theta_max 1.000
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;
Bruker D8 goniometer with CCD area detector  
;
_diffrn_measurement_method       'omega and phi scans'
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_diffrn_radiation_type           CuK\a
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_diffrn_reflns_av_unetI/netI     0.0114
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 1.000
_diffrn_reflns_limit_h_max       12
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_diffrn_reflns_number            47120
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 0.999
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_exptl_absorpt_coefficient_mu    0.573
_exptl_absorpt_correction_T_max  0.8642
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_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
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_exptl_crystal_description       block
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_exptl_crystal_size_max          0.240
_exptl_crystal_size_mid          0.200
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_refine_diff_density_max         0.171
_refine_diff_density_min         -0.122
_refine_diff_density_rms         0.030
_refine_ls_abs_structure_details
;
 Flack x determined using 1253 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.01(4)
_refine_ls_extinction_coef       0.0029(3)
_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   1.044
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     212
_refine_ls_number_reflns         3104
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.044
_refine_ls_R_factor_all          0.0268
_refine_ls_R_factor_gt           0.0261
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0382P)^2^+0.3932P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0679
_refine_ls_wR_factor_ref         0.0684
_reflns_Friedel_coverage         0.710
_reflns_Friedel_fraction_full    1.000
_reflns_Friedel_fraction_max     0.998
_reflns_number_gt                3040
_reflns_number_total             3104
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja5b03229_si_004.cif
_cod_data_source_block           GRR-Actonide
_cod_original_cell_volume        2633.01(11)
_cod_database_code               4129431
_shelx_estimated_absorpt_t_min   0.875
_shelx_estimated_absorpt_t_max   0.924
_shelxl_version_number           2014/6
_shelx_res_checksum              22611
_shelx_hkl_checksum              37712