Catalytic Enantioselective Synthesis of Quaternary Stereocenters via Intermolecular C-Acylation of Silyl Ketene Acetals: Dual Activation of the Electrophile and the Nucleophile
Ara H. Mermerian; Gregory C. Fu; Journal of the American Chemical Society 125 (2003) 4050–4051; doi:10.1021/ja028554k

data_4113624
_publ_section_title
;
 Catalytic Enantioselective Synthesis of Quaternary Stereocenters via
 Intermolecular C-Acylation of Silyl Ketene Acetals: Dual Activation of
 the Electrophile and the Nucleophile
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              4050
_journal_page_last               4051
_journal_paper_doi               10.1021/ja028554k
_journal_volume                  125
_journal_year                    2003
_chemical_formula_sum            'C15 H15 Br3 O4'
_chemical_formula_weight         499.00
_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
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   6.7476(8)
_cell_length_b                   12.5932(15)
_cell_length_c                   20.305(2)
_cell_measurement_temperature    183(2)
_cell_volume                     1725.4(3)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      183(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.2631
_diffrn_reflns_av_sigmaI/netI    0.1688
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            6854
_diffrn_reflns_theta_full        23.29
_diffrn_reflns_theta_max         23.29
_diffrn_reflns_theta_min         3.18
_exptl_absorpt_coefficient_mu    7.027
_exptl_crystal_density_diffrn    1.921
_exptl_crystal_F_000             968
_refine_diff_density_max         1.886
_refine_diff_density_min         -2.216
_refine_diff_density_rms         0.257
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.00(3)
_refine_ls_extinction_coef       0.021(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   1.024
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     203
_refine_ls_number_reflns         2473
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.024
_refine_ls_R_factor_all          0.0906
_refine_ls_R_factor_gt           0.0878
_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^)+(0.1453P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2031
_refine_ls_wR_factor_ref         0.2070
_reflns_number_gt                2303
_reflns_number_total             2473
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja028554ksi20030303_042126.cif
_cod_data_source_block           02015am2
_cod_database_code               4113624