An efficient pathway to high persistence length helicenes from scalable [4]-helicene synthons
Reinhard, Garrett L.; Dowling, Reed; Hewitt, Patrick; Varshney, Vikas; Simone, Davide L.; RSC Advances 15 (2025) 20935–20943; doi:10.1039/D5RA02685G

data_7250577
_publ_section_title
;
 An efficient pathway to high persistence length helicenes from scalable
 [4]-helicene synthons
;
_journal_issue                   26
_journal_name_full               'RSC Advances'
_journal_page_first              20935
_journal_page_last               20943
_journal_paper_doi               10.1039/D5RA02685G
_journal_volume                  15
_journal_year                    2025
_chemical_formula_moiety         '2(C34 H31 O3)'
_chemical_formula_sum            'C68 H62 O6'
_chemical_formula_weight         975.17
_chemical_name_systematic
;
3, 3'- (bis-2-isopropyl-5-methylcyclohexyl) bis(carbonate) helicene
;
_space_group_crystal_system      monoclinic
_space_group_IT_number           5
_space_group_name_Hall           'I 2y'
_space_group_name_H-M_alt        'I 1 2 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2016/6
_audit_update_record
;
2025-06-02 deposited with the CCDC.	2025-06-11 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 151.936(12)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   24.4751(10)
_cell_length_b                   14.97496(10)
_cell_length_c                   30.6550(13)
_cell_measurement_reflns_used    48292
_cell_measurement_temperature    200(2)
_cell_measurement_theta_max      76.8990
_cell_measurement_theta_min      3.6640
_cell_volume                     5286(2)
_computing_cell_refinement       'CrysAlisPro 1.171.42.94a (Rigaku OD, 2023)'
_computing_data_collection       'CrysAlisPro 1.171.42.94a (Rigaku OD, 2023)'
_computing_data_reduction        'CrysAlisPro 1.171.42.94a (Rigaku OD, 2023)'
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL-2016/6 (Sheldrick, 2016)'
_computing_structure_solution    'SHELXS  (Sheldrick, 2008)'
_diffrn_ambient_temperature      200(2)
_diffrn_detector_area_resol_mean 10.0000
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.974
_diffrn_measurement_device_type  'XtaLAB Synergy, Dualflex, HyPix'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0197
_diffrn_reflns_av_unetI/netI     0.0108
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 0.974
_diffrn_reflns_limit_h_max       30
_diffrn_reflns_limit_h_min       -29
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       37
_diffrn_reflns_limit_l_min       -38
_diffrn_reflns_number            74976
_diffrn_reflns_point_group_measured_fraction_full 0.970
_diffrn_reflns_point_group_measured_fraction_max 0.901
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         77.378
_diffrn_reflns_theta_min         1.834
_diffrn_source                   'micro-focus sealed X-ray tube'
_exptl_absorpt_coefficient_mu    0.604
_exptl_absorpt_correction_T_max  0.91241
_exptl_absorpt_correction_T_min  0.91241
_exptl_absorpt_correction_type   sphere
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.42.94a (Rigaku Oxford Diffraction, 2023)
Spherical absorption correction
using equivalent radius and absorption coefficient.
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            'light yellow'
_exptl_crystal_density_diffrn    1.225
_exptl_crystal_description       sphere
_exptl_crystal_F_000             2072
_exptl_crystal_recrystallization_method
'Re-crystallisation from solvent: Acetonitrile'
_exptl_crystal_size_max          0.035
_exptl_crystal_size_mid          0.035
_exptl_crystal_size_min          0.030
_exptl_crystal_size_rad          0.399
_refine_diff_density_max         1.014
_refine_diff_density_min         -0.315
_refine_diff_density_rms         0.060
_refine_ls_abs_structure_details
;
 Flack x determined using 4055 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.07(4)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.036
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     673
_refine_ls_number_reflns         10128
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.036
_refine_ls_R_factor_all          0.0795
_refine_ls_R_factor_gt           0.0774
_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^)+(0.1503P)^2^+5.4986P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2263
_refine_ls_wR_factor_ref         0.2301
_reflns_Friedel_coverage         0.781
_reflns_Friedel_fraction_full    0.937
_reflns_Friedel_fraction_max     0.823
_reflns_number_gt                9720
_reflns_number_total             10128
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5ra02685g2.cif
_cod_data_source_block           11_helicene_adsorpt
_cod_original_cell_volume        5285.7(10)
_cod_original_sg_symbol_H-M      'I 2'
_cod_database_code               7250577
_shelx_shelxl_version_number     2016/6
_shelx_res_checksum              31072