Closely related yet different: a borylene and its dimer are non-interconvertible but connected through reactivity.
Auerhammer, Dominic; Arrowsmith, Merle; Dewhurst, Rian D.; Kupfer, Thomas; Böhnke, Julian; Braunschweig, Holger; Chemical science 9 (2018) 2252–2260; doi:10.1039/c7sc04789d

data_1548595
_publ_section_title
;
 Closely related yet different: a borylene and its dimer are
 non-interconvertible but connected through reactivity.
;
_journal_issue                   8
_journal_name_full               'Chemical science'
_journal_page_first              2252
_journal_page_last               2260
_journal_paper_doi               10.1039/c7sc04789d
_journal_volume                  9
_journal_year                    2018
_chemical_formula_moiety         'C42 H62 B2 N4 S, C7 H8'
_chemical_formula_sum            'C49 H70 B2 N4 S'
_chemical_formula_weight         768.77
_chemical_properties_physical    Air-sensitive,Moisture-sensitive
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014/7
_audit_update_record
;
2017-10-27 deposited with the CCDC.
2018-01-04 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 97.143(10)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   18.966(4)
_cell_length_b                   13.037(3)
_cell_length_c                   18.816(5)
_cell_measurement_reflns_used    3125
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      21.41
_cell_measurement_theta_min      2.26
_cell_volume                     4616.3(19)
_computing_data_collection       'Smart NT ver. 5.63 (Bruker AXS)'
_computing_molecular_graphics    'ShelXLe (Huebschle et all, 2011)'
_computing_publication_material  'SHELXL-2014/6 (Sheldrick, 2014)'
_computing_structure_refinement  'SHELXL-2014/6 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXT (Sheldrick, 2012)'
_diffrn_ambient_temperature      100(2)
_diffrn_detector                 'CCD area detector (Photon)'
_diffrn_detector_area_resol_mean 8.333
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker D8 Quest'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.1654
_diffrn_reflns_av_unetI/netI     0.2109
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       23
_diffrn_reflns_limit_h_min       -23
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            32550
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_theta_full        25.678
_diffrn_reflns_theta_max         25.678
_diffrn_reflns_theta_min         1.900
_diffrn_source                   'sealed tube'
_exptl_absorpt_coefficient_mu    0.107
_exptl_absorpt_correction_T_max  0.7454
_exptl_absorpt_correction_T_min  0.5936
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SadAbs 2014/4 (Bruker AXS)'
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    1.106
_exptl_crystal_description       block
_exptl_crystal_F_000             1672
_exptl_crystal_size_max          0.550
_exptl_crystal_size_mid          0.230
_exptl_crystal_size_min          0.214
_refine_diff_density_max         0.467
_refine_diff_density_min         -0.366
_refine_diff_density_rms         0.060
_refine_ls_extinction_coef       0.0032(6)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2014/7 (Sheldrick 2014'
_refine_ls_goodness_of_fit_ref   0.951
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     565
_refine_ls_number_reflns         8748
_refine_ls_number_restraints     528
_refine_ls_restrained_S_all      0.983
_refine_ls_R_factor_all          0.2190
_refine_ls_R_factor_gt           0.0779
_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^)+(0.0888P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1632
_refine_ls_wR_factor_ref         0.2174
_reflns_Friedel_coverage         0.000
_reflns_number_gt                6377
_reflns_number_total             8748
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c7sc04789d2.cif
_cod_data_source_block           MonoclinP_a
_cod_depositor_comments
'Adding full bibliography for 1548594--1548603.cif.'
_cod_original_cell_volume        4616.2(18)
_cod_database_code               1548595
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.944
_shelx_estimated_absorpt_t_max   0.978
_shelx_res_checksum              6614