Decarboxylation-promoted Pd-catalyzed asymmetric propargylic [3 + 2] annulation for the enantioselective construction of a quaternary stereocenter in 2,3-dihydrofurans.
Li, Kun; Zhu, Fu-Lin; Liu, Zhen-Ting; Tong, Jing; Hu, Xiang-Ping; Organic & biomolecular chemistry 16 (2018) 742–749; doi:10.1039/c7ob02778h

data_7156048
_publ_section_title
;
 Decarboxylation-promoted Pd-catalyzed asymmetric propargylic [3 + 2]
 annulation for the enantioselective construction of a quaternary
 stereocenter in 2,3-dihydrofurans.
;
_journal_issue                   5
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              742
_journal_page_last               749
_journal_paper_doi               10.1039/c7ob02778h
_journal_volume                  16
_journal_year                    2018
_chemical_absolute_configuration ad
_chemical_formula_sum            'C20 H17 Br O3'
_chemical_formula_weight         385.24
_space_group_crystal_system      monoclinic
_space_group_IT_number           5
_space_group_name_Hall           'C 2y'
_space_group_name_H-M_alt        'C 1 2 1'
_symmetry_space_group_name_Hall  'C 2y'
_symmetry_space_group_name_H-M   'C 1 2 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2013
_audit_update_record
;
2017-11-13 deposited with the CCDC.
2018-01-02 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 119.633(3)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   18.502(3)
_cell_length_b                   7.5450(13)
_cell_length_c                   14.387(2)
_cell_measurement_reflns_used    1779
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      45.090
_cell_measurement_theta_min      5.066
_cell_volume                     1745.7(5)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SHELXTL'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2013 (Sheldrick, 2013)'
_computing_structure_solution    'Bruker SHELXTL'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.998
_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  0.0310
_diffrn_reflns_av_unetI/netI     0.0607
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.998
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            5212
_diffrn_reflns_point_group_measured_fraction_full 0.942
_diffrn_reflns_point_group_measured_fraction_max 0.936
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         25.992
_diffrn_reflns_theta_min         2.233
_exptl_absorpt_coefficient_mu    2.369
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.5224
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.466
_exptl_crystal_description       prismatic
_exptl_crystal_F_000             784
_exptl_crystal_size_max          0.28
_exptl_crystal_size_mid          0.17
_exptl_crystal_size_min          0.12
_refine_diff_density_max         0.370
_refine_diff_density_min         -0.283
_refine_diff_density_rms         0.062
_refine_ls_abs_structure_details
; 
 Flack x determined using 922 quotients [(I+)-(I-)]/[(I+)+(I-)] 
 (Parsons and Flack (2004), Acta Cryst. A60, s61). 
;
_refine_ls_abs_structure_Flack   0.009(11)
_refine_ls_extinction_coef       0.0045(10)
_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   0.985
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     220
_refine_ls_number_reflns         3208
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.985
_refine_ls_R_factor_all          0.0568
_refine_ls_R_factor_gt           0.0419
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0620P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1067
_refine_ls_wR_factor_ref         0.1143
_reflns_Friedel_coverage         0.735
_reflns_Friedel_fraction_full    0.874
_reflns_Friedel_fraction_max     0.863
_reflns_number_gt                2500
_reflns_number_total             3208
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c7ob02778h2.cif
_cod_data_source_block           cd15073
_cod_depositor_comments          'Adding full bibliography for 7156048.cif.'
_cod_original_cell_volume        1745.6(5)
_cod_database_code               7156048
_shelxl_version_number           2013-4
_shelx_res_checksum              26218