Enantioselective Construction of Quaternary Stereogenic Carbons by the Lewis Base Catalyzed Additions of Silyl Ketene Imines to Aldehydes
Scott E. Denmark; Tyler W. Wilson; Matthew T. Burk; John R. Heemstra; Journal of the American Chemical Society 129 (2007) 14864–14865; doi:10.1021/ja077134y

data_4110265
_publ_section_title
;
 Enantioselective Construction of Quaternary Stereogenic Carbons by the
 Lewis Base Catalyzed Additions of Silyl Ketene Imines to Aldehydes
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              14864
_journal_page_last               14865
_journal_paper_doi               10.1021/ja077134y
_journal_volume                  129
_journal_year                    2007
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C16 H14 Br N O, C6 H6'
_chemical_formula_sum            'C22 H20 Br N O'
_chemical_formula_weight         394.30
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_audit_update_record
; 
2008-08-08   text and data added, srw 
;
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   5.955(3)
_cell_length_b                   11.936(7)
_cell_length_c                   27.882(15)
_cell_measurement_reflns_used    850
_cell_measurement_temperature    193(2)
_cell_measurement_theta_max      20.91
_cell_measurement_theta_min      2.78
_cell_volume                     1981.8(19)
_computing_cell_refinement       'SAINT V7.23A (Bruker, 2001)'
_computing_data_collection       'SMART V5.625 (Bruker, 2001)'
_computing_data_reduction        'SAINT V7.23A(Bruker, 2001)'
_computing_molecular_graphics    'SHELXTL V6.12 (Bruker, 2001)'
_computing_publication_material  'XCIF (Bruker, 2001)'
_computing_structure_refinement  'SHELXTL V6.12 (Bruker, 2001)'
_computing_structure_solution    'SHELXTL V6.12 (Bruker, 2001)'
_diffrn_ambient_temperature      193(2)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device       'Siemens Platform/CCD'
_diffrn_measurement_method       'profile data from \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'normal-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_radiation_wavelength_id  g71uas
_diffrn_reflns_av_R_equivalents  0.0582
_diffrn_reflns_av_sigmaI/netI    0.0577
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       33
_diffrn_reflns_limit_l_min       -33
_diffrn_reflns_number            20579
_diffrn_reflns_theta_full        25.35
_diffrn_reflns_theta_max         25.35
_diffrn_reflns_theta_min         1.86
_diffrn_standards_decay_%        0.1
_diffrn_standards_interval_time  306
_diffrn_standards_number         45
_exptl_absorpt_coefficient_mu    2.082
_exptl_absorpt_correction_T_max  0.9160
_exptl_absorpt_correction_T_min  0.3965
_exptl_absorpt_correction_type   integration
_exptl_absorpt_process_details   'SHELXTL/XPREP (Bruker, 2001)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.321
_exptl_crystal_description       platy
_exptl_crystal_F_000             808
_exptl_crystal_id                g71uas
_exptl_crystal_preparation
; 
The data crystal was mounted using oil (Parantone-N, Exxon) to a 
0.3 mm cryo-loop (Hampton Research) with the (1 -1 0) scattering 
planes roughly normal to the spindle axis. 
;
_exptl_crystal_size_max          0.80
_exptl_crystal_size_mid          0.12
_exptl_crystal_size_min          0.04
_refine_diff_density_max         0.325
_refine_diff_density_min         -0.259
_refine_diff_density_rms         0.042
_refine_ls_abs_structure_details 'Flack (1983),  1495 Friedels'
_refine_ls_abs_structure_Flack   0.010(10)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.894
_refine_ls_hydrogen_treatment    noref
_refine_ls_matrix_type           full
_refine_ls_number_parameters     258
_refine_ls_number_reflns         3614
_refine_ls_number_restraints     168
_refine_ls_restrained_S_all      0.914
_refine_ls_R_factor_all          0.0701
_refine_ls_R_factor_gt           0.0350
_refine_ls_shift/su_max          0.013
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0370P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0642
_refine_ls_wR_factor_ref         0.0702
_reflns_number_gt                2372
_reflns_number_total             3614
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja077134ysi20070917_042340.cif
_cod_data_source_block           g71uas
_cod_original_cell_volume        1982.0(19)
_cod_original_sg_symbol_Hall     'P 2ac 2ab '
_cod_original_sg_symbol_H-M      'P 21 21 21 '
_cod_database_code               4110265