Electrochemically Driven Strain-Release Dearomative (3+2) Cyclization for the Synthesis of Bicyclo[2.1.1]hexane-Fused Polycyclic Spiroindolines
Zhu, Yanren; Pu, Enfan; Yang, Shaoxiong; Zhao, Dongbo; Xu, Qi; Jiang, Piaopiao; Li, Xiong; Zhang, Hongbin; Chen, Jingbo; Chemical Science  (2026) –; doi:10.1039/D6SC01271J

data_1577115
_publ_section_title
;
 Electrochemically Driven Strain-Release Dearomative (3+2) Cyclization for
 the Synthesis of Bicyclo[2.1.1]hexane-Fused Polycyclic Spiroindolines
;
_journal_name_full               'Chemical Science'
_journal_paper_doi               10.1039/D6SC01271J
_journal_year                    2026
_chemical_formula_moiety         'C28 H25 N O2'
_chemical_formula_sum            'C28 H25 N O2'
_chemical_formula_weight         407.49
_space_group_crystal_system      triclinic
_space_group_IT_number           2
_space_group_name_Hall           '-P 1'
_space_group_name_H-M_alt        'P -1'
_atom_sites_solution_hydrogens   mixed
_atom_sites_solution_primary     direct
_audit_creation_date             2025-09-17
_audit_creation_method
;
FinalCif V89 by Daniel Kratzert, Freiburg 2025,
https://dkratzert.de/finalcif.html
;
_audit_update_record
;
2025-12-21 deposited with the CCDC.	2026-04-15 downloaded from the CCDC.
;
_cell_angle_alpha                86.652(2)
_cell_angle_beta                 82.6790(10)
_cell_angle_gamma                77.8870(10)
_cell_formula_units_Z            4
_cell_length_a                   9.6936(4)
_cell_length_b                   14.0626(5)
_cell_length_c                   16.2000(6)
_cell_measurement_reflns_used    9939
_cell_measurement_temperature    100.00
_cell_measurement_theta_max      27.52
_cell_measurement_theta_min      2.36
_cell_volume                     2140.43(14)
_computing_cell_refinement       'SAINT V8.40B'
_computing_data_reduction        'SAINT V8.40B'
_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_environment      N~2~
_diffrn_ambient_temperature      100.00
_diffrn_detector                 CPAD
_diffrn_detector_area_resol_mean 7.41
_diffrn_detector_type            'Bruker PHOTON'
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device       'three-circle diffractometer'
_diffrn_measurement_device_type  'Bruker D8 VENTURE dual wavelength Mo/Cu'
_diffrn_measurement_method       '\w and \f scans'
_diffrn_measurement_specimen_support 'MiTeGen micromount'
_diffrn_radiation_monochromator  'mirror optics'
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0810
_diffrn_reflns_av_unetI/netI     0.0618
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.998
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            42828
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.998
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.561
_diffrn_reflns_theta_min         1.982
_diffrn_source                   'microfocus sealed X-ray tube'
_diffrn_source_current           1.4
_diffrn_source_power             0.07
_diffrn_source_type              'Incoatec I\ms'
_diffrn_source_voltage           50.0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.079
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.6476
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.1100 before and 0.0845 after correction.
The Ratio of minimum to maximum transmission is 0.8686.
The \l/2 correction factor is Not present.
;
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.265
_exptl_crystal_description       block
_exptl_crystal_F_000             864
_exptl_crystal_size_max          0.22
_exptl_crystal_size_mid          0.18
_exptl_crystal_size_min          0.13
_refine_diff_density_max         0.285
_refine_diff_density_min         -0.331
_refine_diff_density_rms         0.065
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.059
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     563
_refine_ls_number_reflns         9870
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.059
_refine_ls_R_factor_all          0.0839
_refine_ls_R_factor_gt           0.0591
_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^)+(0.0391P)^2^+1.9767P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1229
_refine_ls_wR_factor_ref         0.1391
_reflns_Friedel_coverage         0.000
_reflns_number_gt                7607
_reflns_number_total             9870
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d6sc01271j2.cif
_cod_data_source_block           1_CCDC1
_cod_original_sg_symbol_H-M      P-1
_cod_database_code               1577115
_shelx_shelxl_version_number     2018/3
_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 Riding coordinates:
 N1(H1), N2(H2A)
2.b Secondary CH2 refined with riding coordinates:
 C12(H12A,H12B), C13(H13A,H13B), C20(H20A,H20B), C39(H39A,H39B), C41(H41A,
 H41B), C42(H42A,H42B)
2.c Aromatic/amide H refined with riding coordinates:
 C1(H1A), C2(H2), C3(H3), C4(H4), C5(H5), C16(H16), C17(H17), C18(H18),
 C19(H19), C24(H24), C25(H25), C27(H27), C30(H30), C31(H31), C32(H32), C33(H33),
  C46(H46), C48(H48), C49(H49), C52(H52), C53(H53), C54(H54), C55(H55), C56(H56)
2.d Idealised Me refined as rotating group:
 C9(H9A,H9B,H9C), C28(H28A,H28B,H28C), C37(H37A,H37B,H37C), C50(H50A,H50B,H50C)
;
_olex2_submission_special_instructions 'No special instructions were received'
_shelx_estimated_absorpt_t_min   0.983
_shelx_estimated_absorpt_t_max   0.990
_olex2_diffrn_ambient_temperature_device 'Oxford Cryostream 800'
_shelx_res_checksum              16737