Synthesis of a Helical Analogue of Kekulene: A Flexible π-Expanded Helicene with Large Helical Diameter Acting as a Soft Molecular Spring.
Nakakuki, Yusuke; Hirose, Takashi; Matsuda, Kenji; Journal of the American Chemical Society 140 (2018) 15461–15469; doi:10.1021/jacs.8b09825

data_4133385
_publ_section_title
;
 Synthesis of a Helical Analogue of Kekulene: A Flexible \p-Expanded
 Helicene with Large Helical Diameter Acting as a Soft Molecular Spring.
;
_journal_issue                   45
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              15461
_journal_page_last               15469
_journal_paper_doi               10.1021/jacs.8b09825
_journal_volume                  140
_journal_year                    2018
_chemical_formula_moiety         'C54 H30, 0.368(C6 H14), 0.263(C4 H8 O)'
_chemical_formula_sum            'C57.26 H37.26 O0.26'
_chemical_formula_weight         729.50
_chemical_name_common            'helically twisted kekulene 1'
_chemical_name_systematic
dinaphtho[1'',2'':6,7;1''',2''':6',7']diphenanthro[3,2-a:2',3'-j]anthracene
_space_group_crystal_system      monoclinic
_space_group_IT_number           15
_space_group_name_Hall           '-I 2ya'
_space_group_name_H-M_alt        'I 1 2/a 1'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2016/6
_cell_angle_alpha                90
_cell_angle_beta                 100.653(3)
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   27.6570(7)
_cell_length_b                   7.6139(3)
_cell_length_c                   35.2089(13)
_cell_measurement_reflns_used    8929
_cell_measurement_temperature    93(2)
_cell_measurement_theta_max      30.2270
_cell_measurement_theta_min      2.0700
_cell_volume                     7286.4(4)
_computing_cell_refinement       'CrysAlisPro 1.171.39.43c (Rigaku OD, 2018)'
_computing_data_collection       'CrysAlisPro 1.171.39.43c (Rigaku OD, 2018)'
_computing_data_reduction        'CrysAlisPro 1.171.39.43c (Rigaku OD, 2018)'
_computing_molecular_graphics    'Yadokari-XG (Wakita, Nemoto et al., 2009)'
_computing_publication_material  'Yadokari-XG (Wakita, Nemoto et al., 2009)'
_computing_structure_refinement  'SHELXT 2014/5 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXT 2014/5 (Sheldrick, 2014)'
_diffrn_ambient_temperature      93(2)
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.924
_diffrn_measurement_device_type  'XtaLAB AFC10 (RCD3): fixed-chi single'
_diffrn_measurement_method       '\w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0385
_diffrn_reflns_av_unetI/netI     0.0528
_diffrn_reflns_Laue_measured_fraction_full 0.993
_diffrn_reflns_Laue_measured_fraction_max 0.924
_diffrn_reflns_limit_h_max       26
_diffrn_reflns_limit_h_min       -39
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       49
_diffrn_reflns_limit_l_min       -44
_diffrn_reflns_number            33836
_diffrn_reflns_point_group_measured_fraction_full 0.993
_diffrn_reflns_point_group_measured_fraction_max 0.924
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         30.598
_diffrn_reflns_theta_min         2.070
_diffrn_source                   'Rotating-anode X-ray tube'
_exptl_absorpt_coefficient_mu    0.076
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.39022
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.39.43c (Rigaku Oxford Diffraction, 2018)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.330
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             3063
_exptl_crystal_size_max          0.400
_exptl_crystal_size_mid          0.100
_exptl_crystal_size_min          0.010
_refine_diff_density_max         0.403
_refine_diff_density_min         -0.593
_refine_diff_density_rms         0.056
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.042
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     521
_refine_ls_number_reflns         10354
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.042
_refine_ls_R_factor_all          0.1024
_refine_ls_R_factor_gt           0.0644
_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^)+(0.0970P)^2^+4.0888P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1702
_refine_ls_wR_factor_ref         0.1938
_reflns_Friedel_coverage         0.000
_reflns_number_gt                6788
_reflns_number_total             10354
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ja8b09825_si_002.cif
_cod_data_source_block           KH1
_cod_original_sg_symbol_H-M      'I 2/a'
_cod_database_code               4133385
_shelx_shelxl_version_number     2016/6
_shelx_estimated_absorpt_t_min   0.970
_shelx_estimated_absorpt_t_max   0.999
_shelx_res_checksum              41617
_shelx_hkl_checksum              94824