Copper-catalyzed synthesis of <i>gem</i>-diborylalkanes by B-H bond insertion of α-furyl boryl carbenes.
Song, Daan; Zhao, Xue; Lu, Fei; Sun, Xinhao; Wang, Guanghui; Xu, Liang; Zhao, Ximei; Organic & biomolecular chemistry 24 (2026) 1440–1446; doi:10.1039/d5ob01996f

data_7160992
_publ_section_title
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 Copper-catalyzed synthesis of <i>gem</i>-diborylalkanes by B-H bond
 insertion of &#x3b1;-furyl boryl carbenes.
;
_journal_issue                   7
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              1440
_journal_page_last               1446
_journal_paper_doi               10.1039/d5ob01996f
_journal_volume                  24
_journal_year                    2026
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C16 H26 B2 N2 O6'
_chemical_formula_sum            'C16 H26 B2 N2 O6'
_chemical_formula_weight         364.01
_space_group_crystal_system      orthorhombic
_space_group_IT_number           29
_space_group_name_Hall           'P 2c -2ac'
_space_group_name_H-M_alt        'P c a 21'
_atom_sites_solution_hydrogens   mixed
_atom_sites_solution_primary     dual
_audit_creation_date             2024-05-15
_audit_creation_method
;
Olex2 1.5
(compiled 2024.02.16 svn.r378c4104 for OlexSys, GUI svn.r6928)
;
_audit_update_record
;
2025-09-02 deposited with the CCDC.	2026-01-26 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   10.958
_cell_length_b                   13.200
_cell_length_c                   26.660
_cell_measurement_reflns_used    9137
_cell_measurement_temperature    299.00
_cell_measurement_theta_max      68.257
_cell_measurement_theta_min      3.316
_cell_volume                     3856.252
_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 2019/2 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT 2018/2 (Sheldrick, 2018)'
_diffrn_ambient_temperature      299.00
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Bruker D8 Venture'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0340
_diffrn_reflns_av_unetI/netI     0.0268
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.998
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       32
_diffrn_reflns_limit_l_min       -31
_diffrn_reflns_number            34211
_diffrn_reflns_point_group_measured_fraction_full 0.965
_diffrn_reflns_point_group_measured_fraction_max 0.964
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         68.347
_diffrn_reflns_theta_min         3.315
_diffrn_source_current           1.1
_diffrn_source_power             0.05500000000000001
_diffrn_source_voltage           50.0
_exptl_absorpt_coefficient_mu    0.769
_exptl_absorpt_correction_T_max  0.7531
_exptl_absorpt_correction_T_min  0.4226
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.1638 before and 0.0853 after correction.
The Ratio of minimum to maximum transmission is 0.5611.
The \l/2 correction factor is Not present.
;
_exptl_crystal_density_diffrn    1.254
_exptl_crystal_description       block
_exptl_crystal_F_000             1552
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.15
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.194
_refine_diff_density_min         -0.150
_refine_diff_density_rms         0.028
_refine_ls_abs_structure_details
;
 Refined as an inversion twin.
;
_refine_ls_abs_structure_Flack   0.39(17)
_refine_ls_extinction_coef       0.0009(2)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2019/2 (Sheldrick 2019)'
_refine_ls_goodness_of_fit_ref   1.036
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     499
_refine_ls_number_reflns         6820
_refine_ls_number_restraints     5
_refine_ls_restrained_S_all      1.035
_refine_ls_R_factor_all          0.0351
_refine_ls_R_factor_gt           0.0332
_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^)+(0.0577P)^2^+0.3131P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0904
_refine_ls_wR_factor_ref         0.0922
_reflns_Friedel_coverage         0.887
_reflns_Friedel_fraction_full    0.930
_reflns_Friedel_fraction_max     0.929
_reflns_number_gt                6434
_reflns_number_total             6820
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5ob01996f2.cif
_cod_data_source_block           cu_240514wgh_0m
_cod_original_cell_volume        3856.3
_cod_database_code               7160992
_shelx_shelxl_version_number     2019/2
_shelx_estimated_absorpt_t_max   0.927
_shelx_estimated_absorpt_t_min   0.861
_olex2_refinement_description
;
1. Twinned data refinement
 Scales: 0.61(17)
 0.39(17)
2. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups
 At 1.5 times of:
  All C(H,H,H) groups
3. Restrained distances
 B2-H2B = B2-H2A = B3-H3B = B3-H3A
 1.12 with sigma of 0.001
4.a Ternary CH refined with riding coordinates:
 C24(H24), C8(H8)
4.b Secondary CH2 refined with riding coordinates:
 C31(H31A,H31B), C28(H28A,H28B), C10(H10A,H10B), C12(H12A,H12B)
4.c Aromatic/amide H refined with riding coordinates:
 C22(H22), C6(H6)
4.d Idealised Me refined as rotating group:
 C30(H30A,H30B,H30C), C5(H5A,H5B,H5C), C21(H21A,H21B,H21C), C26(H26A,H26B,
 H26C), C11(H11A,H11B,H11C), C17(H17A,H17B,H17C), C14(H14A,H14B,H14C), C27(H27A,
 H27B,H27C), C25(H25A,H25B,H25C), C15(H15A,H15B,H15C), C16(H16A,H16B,H16C),
 C1(H1A,H1B,H1C)
;
_shelx_res_checksum              92289
_olex2_submission_special_instructions 'No special instructions were received'