Copper-Catalyzed Decarboxylative Propargylic Alkylation of Enol Carbonates: Stereoselective Synthesis of Quaternary α-Amino Acids
Xia, Jin-Tao; Li, Ling; Hu, Xiang-Ping; ACS Catalysis 11 (2021) 11843–11848; doi:10.1021/acscatal.1c03421

data_4519060
_publ_section_title
;
 Copper-Catalyzed Decarboxylative Propargylic Alkylation of Enol
 Carbonates: Stereoselective Synthesis of Quaternary \a-Amino Acids
;
_journal_issue                   19
_journal_name_full               'ACS Catalysis'
_journal_page_first              11843
_journal_page_last               11848
_journal_paper_doi               10.1021/acscatal.1c03421
_journal_volume                  11
_journal_year                    2021
_chemical_absolute_configuration ad
_chemical_formula_sum            'C20 H18 Br N O3'
_chemical_formula_weight         400.26
_space_group_crystal_system      orthorhombic
_space_group_IT_number           19
_space_group_name_Hall           'P 2ac 2ab'
_space_group_name_H-M_alt        'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2013
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   8.1288(2)
_cell_length_b                   13.7875(4)
_cell_length_c                   16.7891(6)
_cell_measurement_reflns_used    6755
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      48.610
_cell_measurement_theta_min      4.852
_cell_volume                     1881.65(10)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2013 (Sheldrick, 2013)'
_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0381
_diffrn_reflns_av_unetI/netI     0.0461
_diffrn_reflns_Laue_measured_fraction_full 0.996
_diffrn_reflns_Laue_measured_fraction_max 0.996
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            16687
_diffrn_reflns_point_group_measured_fraction_full 0.993
_diffrn_reflns_point_group_measured_fraction_max 0.994
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         25.994
_diffrn_reflns_theta_min         2.784
_exptl_absorpt_coefficient_mu    2.202
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.4326
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.413
_exptl_crystal_description       prismatic
_exptl_crystal_F_000             816
_exptl_crystal_size_max          0.190
_exptl_crystal_size_mid          0.150
_exptl_crystal_size_min          0.120
_refine_diff_density_max         0.817
_refine_diff_density_min         -0.713
_refine_diff_density_rms         0.045
_refine_ls_abs_structure_details
; 
 Flack x determined using 1156 quotients [(I+)-(I-)]/[(I+)+(I-)] 
 (Parsons and Flack (2004), Acta Cryst. A60, s61). 
;
_refine_ls_abs_structure_Flack   0.020(6)
_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   1.028
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     229
_refine_ls_number_reflns         3660
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.028
_refine_ls_R_factor_all          0.0498
_refine_ls_R_factor_gt           0.0389
_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^)+(0.0381P)^2^+0.9057P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0948
_refine_ls_wR_factor_ref         0.1013
_reflns_Friedel_coverage         0.738
_reflns_Friedel_fraction_full    0.990
_reflns_Friedel_fraction_max     0.990
_reflns_number_gt                3067
_reflns_number_total             3660
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            cs1c03421_si_002.cif
_cod_data_source_block           mo_d8v19227_0m
_cod_database_code               4519060
_shelx_estimated_absorpt_t_min   0.680
_shelx_estimated_absorpt_t_max   0.778
_shelxl_version_number           2013-4
_shelx_res_checksum              40426
_shelx_hkl_checksum              18611