Asymmetric synthesis of spiro[oxindole-3,2'-pyrrolidine]s through organocatalytic 1,3-dipolar cycloaddition <i>via</i> cycloreversion of precursor isatinimine homodimers.
Liu, Qian; Yoshikawa, Isao; Okuyama, Kohsaku; Kudo, Kazuaki; Organic & biomolecular chemistry 23 (2025) 1098–1103; doi:10.1039/d4ob01727g

data_7160305
_publ_section_title
;
 Asymmetric synthesis of spiro[oxindole-3,2'-pyrrolidine]s through
 organocatalytic 1,3-dipolar cycloaddition <i>via</i> cycloreversion of
 precursor isatinimine homodimers.
;
_journal_issue                   5
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              1098
_journal_page_last               1103
_journal_paper_doi               10.1039/d4ob01727g
_journal_volume                  23
_journal_year                    2025
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C20 H16 Br N3 O2'
_chemical_formula_sum            'C20 H16 Br N3 O2'
_chemical_formula_weight         410.27
_chemical_name_systematic        adduct_6i
_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   mixed
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2019/3
_audit_update_record
;
2024-10-23 deposited with the CCDC.	2024-12-19 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   7.89950(10)
_cell_length_b                   10.5371(2)
_cell_length_c                   21.3743(3)
_cell_measurement_reflns_used    6200
_cell_measurement_temperature    93(2)
_cell_measurement_theta_max      72.2410
_cell_measurement_theta_min      4.1580
_cell_volume                     1779.15(5)
_computing_cell_refinement       'CrysAlisPro 1.171.40.84a (Rigaku OD, 2020)'
_computing_data_collection       'CrysAlisPro 1.171.41.107a (Rigaku OD, 2021)'
_computing_data_reduction        'CrysAlisPro 1.171.40.84a (Rigaku OD, 2020)'
_computing_molecular_graphics    'Yadokari-XG (Wakita, Nemoto et al., 2009)'
_computing_publication_material  'Yadokari-XG (Wakita, Nemoto et al., 2009)'
_computing_structure_refinement  'SHELXL-2019/3 (Sheldrick, 2019)'
_computing_structure_solution    'SHELXS Version 2013/1 (Sheldrick, 2008)'
_diffrn_ambient_temperature      93(2)
_diffrn_detector_area_resol_mean 5.811
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.980
_diffrn_measurement_device_type  'Rigaku XtaLAB P200'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0293
_diffrn_reflns_av_unetI/netI     0.0303
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.980
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            10363
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.970
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         73.011
_diffrn_reflns_theta_min         4.137
_diffrn_source                   'rotating anode X-ray generator'
_exptl_absorpt_coefficient_mu    3.313
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.79272
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.40.84a (Rigaku Oxford Diffraction, 2020)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.532
_exptl_crystal_description       needle
_exptl_crystal_F_000             832
_exptl_crystal_recrystallization_method
'Re-crystallisation from solvent: chloroform and hexane'
_exptl_crystal_size_max          0.200
_exptl_crystal_size_mid          0.040
_exptl_crystal_size_min          0.010
_refine_diff_density_max         0.320
_refine_diff_density_min         -0.426
_refine_diff_density_rms         0.054
_refine_ls_abs_structure_details
;
 Flack x determined using 1362 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   -0.029(10)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.127
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     239
_refine_ls_number_reflns         3451
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.127
_refine_ls_R_factor_all          0.0258
_refine_ls_R_factor_gt           0.0248
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0337P)^2^+0.5855P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0670
_refine_ls_wR_factor_ref         0.0673
_reflns_Friedel_coverage         0.714
_reflns_Friedel_fraction_full    0.999
_reflns_Friedel_fraction_max     0.955
_reflns_number_gt                3322
_reflns_number_total             3451
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d4ob01727g2.cif
_cod_data_source_block           adduct_6i
_cod_depositor_comments          'Adding full bibliography for 7160305.cif.'
_cod_database_code               7160305
_shelx_shelxl_version_number     2019/3
_shelx_estimated_absorpt_t_min   0.557
_shelx_estimated_absorpt_t_max   0.968
_shelx_res_checksum              89374