Synthesis of hexahydroisobenzofuran-1(3<i>H</i>)-ones <i>via</i> pyridine-boryl radical-catalyzed intramolecular cascade cyclization of alkene-tethered cyclobutyl ketones.
Yang, Xiao-Ye; Huang, Hua; Wu, Qiong; Tan, Yun-Xuan; Tian, Ping; Organic & biomolecular chemistry 23 (2025) 10057–10061; doi:10.1039/d5ob01566a

data_7160812
_publ_section_title
;
 Synthesis of hexahydroisobenzofuran-1(3<i>H</i>)-ones <i>via</i>
 pyridine-boryl radical-catalyzed intramolecular cascade cyclization of
 alkene-tethered cyclobutyl ketones.
;
_journal_issue                   44
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              10057
_journal_page_last               10061
_journal_paper_doi               10.1039/d5ob01566a
_journal_volume                  23
_journal_year                    2025
_chemical_absolute_configuration unk
_chemical_formula_moiety         'C21 H20 O3'
_chemical_formula_sum            'C21 H20 O3'
_chemical_formula_weight         320.37
_space_group_crystal_system      monoclinic
_space_group_IT_number           4
_space_group_name_Hall           'P 2yb'
_space_group_name_H-M_alt        'P 1 21 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_audit_creation_date             2025-10-14
_audit_creation_method
;
Olex2 1.5
(compiled 2025.07.13 svn.rb7424aed for OlexSys, GUI svn.r7314)
;
_audit_update_record
;
2025-10-15 deposited with the CCDC.	2025-10-17 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 103.208(6)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   11.4404(9)
_cell_length_b                   5.6542(4)
_cell_length_c                   13.1370(9)
_cell_measurement_reflns_used    2002
_cell_measurement_temperature    193.00
_cell_measurement_theta_max      67.84
_cell_measurement_theta_min      3.46
_cell_volume                     827.30(11)
_computing_cell_refinement       'SAINT V8.41 (?, 2016)'
_computing_data_reduction        'SAINT V8.41 (?, 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      193.00
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0582
_diffrn_reflns_av_unetI/netI     0.0648
_diffrn_reflns_Laue_measured_fraction_full 0.992
_diffrn_reflns_Laue_measured_fraction_max 0.992
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            5617
_diffrn_reflns_point_group_measured_fraction_full 0.923
_diffrn_reflns_point_group_measured_fraction_max 0.920
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         68.260
_diffrn_reflns_theta_min         3.456
_diffrn_source_current           1.1
_diffrn_source_power             0.05500000000000001
_diffrn_source_voltage           50.0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.680
_exptl_absorpt_correction_T_max  0.7531
_exptl_absorpt_correction_T_min  0.6343
_exptl_absorpt_correction_type   none
_exptl_absorpt_process_details
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.1278 before and 0.0648 after correction.
The Ratio of minimum to maximum transmission is 0.8423.
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    1.286
_exptl_crystal_description       block
_exptl_crystal_F_000             340
_exptl_crystal_size_max          0.1
_exptl_crystal_size_mid          0.09
_exptl_crystal_size_min          0.08
_refine_diff_density_max         0.157
_refine_diff_density_min         -0.183
_refine_diff_density_rms         0.042
_refine_ls_abs_structure_details
;
 Flack x determined using 791 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   -0.1(2)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.077
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     217
_refine_ls_number_reflns         2796
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.077
_refine_ls_R_factor_all          0.0576
_refine_ls_R_factor_gt           0.0415
_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^)+(0.0452P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0944
_refine_ls_wR_factor_ref         0.0998
_reflns_Friedel_coverage         0.672
_reflns_Friedel_fraction_full    0.836
_reflns_Friedel_fraction_max     0.831
_reflns_number_gt                2276
_reflns_number_total             2796
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5ob01566a2.cif
_cod_data_source_block           251014ha_z1160218_0m
_cod_depositor_comments
'Adding full bibliography for 7160811--7160812.cif.'
_cod_database_code               7160812
_shelx_shelxl_version_number     2018/3
_shelx_estimated_absorpt_t_max   0.948
_shelx_estimated_absorpt_t_min   0.935
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups
2.a Ternary CH refined with riding coordinates:
 C2(H2), C3(H3), C4(H4), C11(H11)
2.b Secondary CH2 refined with riding coordinates:
 C12(H12A,H12B), C13(H13A,H13B), C21(H21A,H21B)
2.c Aromatic/amide H refined with riding coordinates:
 C6(H6), C7(H7), C8(H8), C9(H9), C10(H10), C16(H16), C17(H17), C18(H18),
 C19(H19), C20(H20)
;
_shelx_res_checksum              54159
_olex2_submission_special_instructions 'No special instructions were received'