Highly Enantioselective, Hydrogen-Bond-Donor Catalyzed Additions to Oxetanes.
Strassfeld, Daniel A.; Wickens, Zachary K.; Picazo, Elias; Jacobsen, Eric N.; Journal of the American Chemical Society 142 (2020) 9175–9180; doi:10.1021/jacs.0c03991

data_4134917
_publ_section_title
;
 Highly Enantioselective, Hydrogen-Bond-Donor Catalyzed Additions to
 Oxetanes.
;
_journal_issue                   20
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              9175
_journal_page_last               9180
_journal_paper_doi               10.1021/jacs.0c03991
_journal_volume                  142
_journal_year                    2020
_chemical_absolute_configuration ad
_chemical_formula_sum            'C20 H24 Br F3 O2 Si'
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_space_group_name_Hall           'P 1'
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_cell_measurement_reflns_used    9804
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      27.0
_cell_measurement_theta_min      2.57
_cell_volume                     1045.39(4)
_computing_cell_refinement       'SAINT 8.37A (Bruker-AXS, 2015)'
_computing_data_reduction        'SAINT 8.37A (Bruker-AXS, 2015)'
_computing_molecular_graphics    'Bruker SHELXTL (Sheldrick, 2015)'
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;
Bruker D8 goniometer with CCD area detector  
;
_diffrn_measurement_method       'omega and phi scans'
_diffrn_radiation_monochromator  graphite
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_diffrn_radiation_wavelength     0.71073
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_diffrn_reflns_av_unetI/netI     0.0189
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_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
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_diffrn_reflns_limit_l_min       -15
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_diffrn_reflns_point_group_measured_fraction_full 0.995
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_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.465
_exptl_crystal_description       block
_exptl_crystal_F_000             472
_exptl_crystal_size_max          0.200
_exptl_crystal_size_mid          0.160
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_refine_diff_density_min         -0.267
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_refine_ls_abs_structure_details
;
 Flack x determined using 4241 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.005(2)
_refine_ls_extinction_method     none
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_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
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_refine_ls_number_reflns         9165
_refine_ls_number_restraints     310
_refine_ls_restrained_S_all      1.030
_refine_ls_R_factor_all          0.0247
_refine_ls_R_factor_gt           0.0234
_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^)+(0.0385P)^2^+0.2223P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0582
_refine_ls_wR_factor_ref         0.0587
_reflns_Friedel_coverage         0.990
_reflns_Friedel_fraction_full    0.991
_reflns_Friedel_fraction_max     0.988
_reflns_number_gt                8882
_reflns_number_total             9165
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja0c03991_si_004.cif
_cod_data_source_block           DAS-III-249-1
_cod_depositor_comments
'Adding full bibliography for 4134915--4134918.cif.'
_cod_database_code               4134917
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.683
_shelx_estimated_absorpt_t_max   0.790
_shelx_res_checksum              32324
_shelx_hkl_checksum              45816