Enantioselective synthesis of spiro-<i>N</i>,<i>O</i>-ketals <i>via</i> iridium and Brønsted acid co-catalyzed asymmetric formal [4+2] cycloaddition.
Xie, Xiang-Qi; Li, Xingguang; Liu, Pei-Nian; Chemical communications (Cambridge, England) 60 (2024) 1448–1451; doi:10.1039/d3cc05923e

data_7132575
_publ_section_title
;
 Enantioselective synthesis of spiro-<i>N</i>,<i>O</i>-ketals <i>via</i>
 iridium and Br&#xf8;nsted acid co-catalyzed asymmetric formal [4+2]
 cycloaddition.
;
_journal_issue                   11
_journal_name_full               'Chemical communications (Cambridge, England)'
_journal_page_first              1448
_journal_page_last               1451
_journal_paper_doi               10.1039/d3cc05923e
_journal_volume                  60
_journal_year                    2024
_chemical_absolute_configuration syn
_chemical_formula_moiety         'C22 H23 N O2, 1[C4H8O2]'
_chemical_formula_sum            'C26 H31 N O4'
_chemical_formula_weight         421.52
_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
_atom_sites_solution_primary     dual
_audit_creation_date             2023-10-18
_audit_creation_method
;
Olex2 1.5
(compiled 2023.08.24 svn.re1ec1418 for OlexSys, GUI svn.r6817)
;
_audit_update_record
;
2023-11-27 deposited with the CCDC.	2024-01-03 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   8.9352(6)
_cell_length_b                   9.9706(7)
_cell_length_c                   26.0378(18)
_cell_measurement_reflns_used    9919
_cell_measurement_temperature    295.00
_cell_measurement_theta_max      68.443
_cell_measurement_theta_min      3.395
_cell_volume                     2319.7(3)
_computing_cell_refinement       'SAINT V8.40B (?, 2016)'
_computing_data_reduction        'SAINT V8.40B (?, 2016)'
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2018/3 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT 2018/2 (Sheldrick, 2018)'
_diffrn_ambient_temperature      295.00
_diffrn_measured_fraction_theta_full 0.980
_diffrn_measured_fraction_theta_max 0.978
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0441
_diffrn_reflns_av_unetI/netI     0.0304
_diffrn_reflns_Laue_measured_fraction_full 0.980
_diffrn_reflns_Laue_measured_fraction_max 0.978
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       30
_diffrn_reflns_limit_l_min       -31
_diffrn_reflns_number            21429
_diffrn_reflns_point_group_measured_fraction_full 0.984
_diffrn_reflns_point_group_measured_fraction_max 0.980
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         68.444
_diffrn_reflns_theta_min         7.113
_diffrn_source_current           1.2
_diffrn_source_power             0.06
_diffrn_source_voltage           50.0
_exptl_absorpt_coefficient_mu    0.646
_exptl_absorpt_correction_T_max  0.7531
_exptl_absorpt_correction_T_min  0.6482
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.1122 before and 0.0605 after correction.
The Ratio of minimum to maximum transmission is 0.8607.
The \l/2 correction factor is Not present.
;
_exptl_crystal_colour            'clear light colourless'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   light
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.207
_exptl_crystal_description       block
_exptl_crystal_F_000             904
_exptl_crystal_size_max          0.19
_exptl_crystal_size_mid          0.17
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.190
_refine_diff_density_min         -0.181
_refine_diff_density_rms         0.036
_refine_ls_abs_structure_details
;
 Flack x determined using 1612 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   -0.02(8)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.081
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     229
_refine_ls_number_reflns         4181
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.081
_refine_ls_R_factor_all          0.0516
_refine_ls_R_factor_gt           0.0502
_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^)+(0.1062P)^2^+0.2044P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1550
_refine_ls_wR_factor_ref         0.1567
_reflns_Friedel_coverage         0.746
_reflns_Friedel_fraction_full    0.990
_reflns_Friedel_fraction_max     0.984
_reflns_number_gt                3983
_reflns_number_total             4181
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d3cc05923e2.cif
_cod_data_source_block           xxq_3aa_2_0ma
_cod_depositor_comments
'Adding full bibliography for 7132574--7132575.cif.'
_cod_database_code               7132575
_shelx_shelxl_version_number     2018/3
_shelx_estimated_absorpt_t_max   0.909
_shelx_estimated_absorpt_t_min   0.887
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups, All N(H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2.a Ternary CH refined with riding coordinates:
 C10(H10)
2.b Secondary CH2 refined with riding coordinates:
 C9(H9A,H9B)
2.c Aromatic/amide H refined with riding coordinates:
 N1(H1), C16(H16), C14(H14), C17(H17), C6(H6), C13(H13), C5(H5), C4(H4), C3(H3)
2.d X=CH2 refined with riding coordinates:
 C18(H18A,H18B)
2.e Idealised Me refined as rotating group:
 C20(H20A,H20B,H20C), C21(H21A,H21B,H21C), C22(H22A,H22B,H22C)
;
_smtbx_masks_void_probe_radius   1.2
_smtbx_masks_void_truncation_radius 1.2
_shelx_res_checksum              40068
_shelx_hkl_checksum              4995
_shelx_fab_checksum              90342
_olex2_submission_special_instructions 'No special instructions were received'