π-Curved Blatter radicals: Blatter helicenes.
Singh, Hemant K.; Bodzioch, Agnieszka; Pietrzak, Anna; Kaszyński, Piotr; Chemical communications (Cambridge, England) 61 (2025) 496–499; doi:10.1039/d4cc05704j

data_1573284
_publ_section_title
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 &#x3c0;-Curved Blatter radicals: Blatter helicenes.
;
_journal_issue                   3
_journal_name_full               'Chemical communications (Cambridge, England)'
_journal_page_first              496
_journal_page_last               499
_journal_paper_doi               10.1039/d4cc05704j
_journal_volume                  61
_journal_year                    2025
_chemical_formula_moiety         'C27 H16 N3 O'
_chemical_formula_sum            'C27 H16 N3 O'
_chemical_formula_weight         398.43
_space_group_crystal_system      trigonal
_space_group_IT_number           148
_space_group_name_Hall           '-R 3'
_space_group_name_H-M_alt        'R -3 :H'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     other
_audit_creation_method           SHELXL-2019/3
_audit_update_record
;
2024-03-11 deposited with the CCDC.	2024-11-25 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                120
_cell_formula_units_Z            18
_cell_length_a                   43.1890(5)
_cell_length_b                   43.1890(5)
_cell_length_c                   5.1711(3)
_cell_measurement_reflns_used    12698
_cell_measurement_temperature    100.01(11)
_cell_measurement_theta_max      77.9290
_cell_measurement_theta_min      3.5250
_cell_volume                     8353.3(5)
_computing_cell_refinement       'CrysAlisPro 1.171.40.84a (Rigaku OD, 2020)'
_computing_data_collection       'CrysAlisPro 1.171.40.84a (Rigaku OD, 2020)'
_computing_data_reduction        'CrysAlisPro 1.171.40.84a (Rigaku OD, 2020)'
_computing_structure_refinement  'SHELXL-2019/3 (Sheldrick, 2019)'
_computing_structure_solution    'SHELXT 2019/3 (Sheldrick, 2019)'
_diffrn_ambient_temperature      100.01(11)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.977
_diffrn_measurement_device_type  'XtaLAB Synergy, Dualflex, Pilatus 300K'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0380
_diffrn_reflns_av_unetI/netI     0.0222
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.977
_diffrn_reflns_limit_h_max       54
_diffrn_reflns_limit_h_min       -54
_diffrn_reflns_limit_k_max       53
_diffrn_reflns_limit_k_min       -52
_diffrn_reflns_limit_l_max       5
_diffrn_reflns_limit_l_min       -6
_diffrn_reflns_number            28218
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.977
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         78.750
_diffrn_reflns_theta_min         3.545
_diffrn_source                   'micro-focus sealed X-ray tube'
_exptl_absorpt_coefficient_mu    0.703
_exptl_absorpt_correction_T_max  1.000
_exptl_absorpt_correction_T_min  0.498
_exptl_absorpt_correction_type   gaussian
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.40.84a (Rigaku Oxford Diffraction, 2020)
Numerical absorption correction based on gaussian integration over
a multifaceted crystal model
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            brown
_exptl_crystal_density_diffrn    1.426
_exptl_crystal_description       needle
_exptl_crystal_F_000             3726
_exptl_crystal_recrystallization_method
'Re-crystallisation from solvent: mixture of  dichloromethane and acetinitrile'
_exptl_crystal_size_max          0.370
_exptl_crystal_size_mid          0.028
_exptl_crystal_size_min          0.020
_refine_diff_density_max         0.205
_refine_diff_density_min         -0.185
_refine_diff_density_rms         0.035
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.029
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     280
_refine_ls_number_reflns         3920
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.029
_refine_ls_R_factor_all          0.0505
_refine_ls_R_factor_gt           0.0375
_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^)+(0.0463P)^2^+7.3502P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0947
_refine_ls_wR_factor_ref         0.1022
_reflns_Friedel_coverage         0.000
_reflns_number_gt                3106
_reflns_number_total             3920
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d4cc05704j2.cif
_cod_data_source_block           5hel_DCM_MeCN
_cod_depositor_comments
'Adding full bibliography for 1573283--1573285.cif.'
_cod_database_code               1573284
_shelx_shelxl_version_number     2019/3
_shelx_estimated_absorpt_t_min   0.781
_shelx_estimated_absorpt_t_max   0.986
_oxdiff_exptl_absorpt_empirical_full_min 0.641
_oxdiff_exptl_absorpt_empirical_full_max 2.344
_oxdiff_exptl_absorpt_empirical_details
;
Empirical correction (ABSPACK) includes:
- Absorption correction using spherical harmonics
- Frame scaling
;
_shelx_res_checksum              73793
_shelx_hkl_checksum              51372
_shelx_fab_checksum              5040