Asymmetric Synthesis of Glutamic Acid Derivatives by Silver-Catalyzed Conjugate Addition-Elimination Reactions.
Yuan, Yang; Yu, Bo; Bai, Xing-Feng; Xu, Zheng; Zheng, Zhan-Jiang; Cui, Yu-Ming; Cao, Jian; Xu, Li-Wen; Organic letters 19 (2017) 4896–4899; doi:10.1021/acs.orglett.7b02378

data_1547576
_publ_section_title
;
 Asymmetric Synthesis of Glutamic Acid Derivatives by Silver-Catalyzed
 Conjugate Addition-Elimination Reactions.
;
_journal_issue                   18
_journal_name_full               'Organic letters'
_journal_page_first              4896
_journal_page_last               4899
_journal_paper_doi               10.1021/acs.orglett.7b02378
_journal_volume                  19
_journal_year                    2017
_chemical_formula_sum            'C21 H19 Br N2 O6'
_chemical_formula_weight         475.29
_space_group_crystal_system      triclinic
_space_group_IT_number           1
_space_group_name_Hall           'P 1'
_space_group_name_H-M_alt        'P 1'
_symmetry_space_group_name_Hall  'P 1'
_symmetry_space_group_name_H-M   'P 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014/7
_cell_angle_alpha                83.24(2)
_cell_angle_beta                 79.64(2)
_cell_angle_gamma                79.50(2)
_cell_formula_units_Z            1
_cell_length_a                   7.040(9)
_cell_length_b                   7.063(9)
_cell_length_c                   10.762(13)
_cell_measurement_reflns_used    2181
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      27.45
_cell_measurement_theta_min      2.47
_cell_volume                     515.6(11)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    'Bruker SHELXTL'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.877
_diffrn_measured_fraction_theta_max 0.877
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0467
_diffrn_reflns_av_unetI/netI     0.0835
_diffrn_reflns_Laue_measured_fraction_full 0.877
_diffrn_reflns_Laue_measured_fraction_max 0.877
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            2974
_diffrn_reflns_point_group_measured_fraction_full 0.581
_diffrn_reflns_point_group_measured_fraction_max 0.581
_diffrn_reflns_theta_full        25.097
_diffrn_reflns_theta_max         25.097
_diffrn_reflns_theta_min         2.944
_exptl_absorpt_coefficient_mu    2.034
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.3133
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.531
_exptl_crystal_description       block
_exptl_crystal_F_000             242
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.964
_refine_diff_density_min         -1.336
_refine_diff_density_rms         0.150
_refine_ls_abs_structure_details
; 
 Flack x determined using 437 quotients [(I+)-(I-)]/[(I+)+(I-)] 
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259). 
;
_refine_ls_abs_structure_Flack   0.161(18)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.062
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     273
_refine_ls_number_reflns         2143
_refine_ls_number_restraints     16
_refine_ls_restrained_S_all      1.059
_refine_ls_R_factor_all          0.0835
_refine_ls_R_factor_gt           0.0770
_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^)+(0.1860P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2095
_refine_ls_wR_factor_ref         0.2247
_reflns_Friedel_coverage         0.325
_reflns_Friedel_fraction_full    0.285
_reflns_Friedel_fraction_max     0.285
_reflns_number_gt                1938
_reflns_number_total             2143
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ol7b02378_si_003.cif
_cod_data_source_block           123
_cod_database_code               1547576
_shelx_shelxl_version_number     2014/7
_shelx_res_checksum              18177
_shelx_hkl_checksum              30886