Fraternal twins: B2O2- or B2N2-doped polycyclic π systems and their formation mechanism via regiodivergent Au-versus amine catalyzed cycloadditions
Mittag, Simon M.; Klopf, Jonas; Virovets, Alexander; Peresypkina, Eugenia V.; Lerner, Hans-Wolfram; Helten, Holger; Wagner, Matthias; Dalton Transactions  (2026) –; doi:10.1039/D6DT00412A

data_7720374
_publ_section_title
;
 Fraternal twins: B<sub>2</sub>O<sub>2</sub>- or
 B<sub>2</sub>N<sub>2</sub>-doped polycyclic &#x3c0; systems and their
 formation mechanism <i>via</i> regiodivergent Au- <i>versus</i>
 amine-catalyzed cyclizations.
;
_journal_issue                   14
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              5553
_journal_page_last               5564
_journal_paper_doi               10.1039/d6dt00412a
_journal_volume                  55
_journal_year                    2026
_chemical_formula_moiety         'C16 H8 Br2'
_chemical_formula_sum            'C16 H8 Br2'
_chemical_formula_weight         360.04
_space_group_crystal_system      orthorhombic
_space_group_IT_number           18
_space_group_name_Hall           'P 2 2ab'
_space_group_name_H-M_alt        'P 21 21 2'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_atom_sites_solution_secondary   difmap
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_audit_update_record
;
2026-01-15 deposited with the CCDC.	2026-02-27 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
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_cell_length_b                   14.2304(4)
_cell_length_c                   3.93254(13)
_cell_measurement_reflns_used    4043
_cell_measurement_temperature    173(2)
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_cell_measurement_theta_min      3.4030
_cell_volume                     641.65(4)
_computing_cell_refinement       'CrysAlisPro 1.171.42.43a (Rigaku OD, 2022)'
_computing_data_collection       'X-Area (Stoe & Cie, 2001)'
_computing_data_reduction        'CrysAlisPro 1.171.42.43a (Rigaku OD, 2022)'
_computing_structure_refinement  'SHELXL-2019/2 (Sheldrick, 2019)'
_computing_structure_solution    'SHELXT (G. M. Sheldrick, 2015)'
_diffrn_ambient_temperature      173(2)
_diffrn_detector                 'image plate'
_diffrn_detector_area_resol_mean 6.67
_diffrn_detector_type            'STOE image plate (34 cm diameter)'
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device       '2-circle goniometer'
_diffrn_measurement_device_type  'STOE IPDS II two-circle-diffractometer'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0370
_diffrn_reflns_av_unetI/netI     0.0218
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 0.998
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       4
_diffrn_reflns_limit_l_min       -5
_diffrn_reflns_number            7931
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.893
_diffrn_reflns_theta_min         2.281
_diffrn_source                   'Genix 3D I\mS microfocus X-ray source'
_exptl_absorpt_coefficient_mu    6.293
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.22204
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.42.43a (Rigaku Oxford Diffraction, 2022)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.864
_exptl_crystal_description       'elongated prism'
_exptl_crystal_F_000             348
_exptl_crystal_size_max          0.320
_exptl_crystal_size_mid          0.075
_exptl_crystal_size_min          0.060
_refine_diff_density_max         0.411
_refine_diff_density_min         -0.236
_refine_diff_density_rms         0.061
_refine_ls_abs_structure_details
;
 Refined as an inversion twin.
;
_refine_ls_abs_structure_Flack   0.065(18)
_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     83
_refine_ls_number_reflns         1534
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.059
_refine_ls_R_factor_all          0.0228
_refine_ls_R_factor_gt           0.0205
_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^)+(0.0256P)^2^+0.1616P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0501
_refine_ls_wR_factor_ref         0.0518
_reflns_Friedel_coverage         0.635
_reflns_Friedel_fraction_full    1.000
_reflns_Friedel_fraction_max     1.000
_reflns_number_gt                1450
_reflns_number_total             1534
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d6dt00412a2.cif
_cod_data_source_block           S6_wa3657_sm308
_cod_depositor_comments
'Adding full bibliography for 7720366--7720383.cif.'
_cod_database_code               7720374
_shelx_shelxl_version_number     2019/3
_shelx_estimated_absorpt_t_min   0.238
_shelx_estimated_absorpt_t_max   0.704
_shelx_res_checksum              57966