Syntheses and structures of [7]helicene and double helicene based on dithieno[2,3-b:2′,3′-d]thiophene
Liu, Xinming; Sun, Huiliang; Xu, Wan; Wan, Shisheng; Shi, Jianwu; Li, Chunli; Wang, Hua; Organic Chemistry Frontiers 5 (2018) 1257–; doi:10.1039/C7QO01049D

data_1553952
_publ_section_title
;
 Syntheses and structures of [7]helicene and double helicene based on
 dithieno[2,3-b:2&#x2032;,3&#x2032;-d]thiophene
;
_journal_issue                   8
_journal_name_full               'Organic Chemistry Frontiers'
_journal_page_first              1257
_journal_paper_doi               10.1039/C7QO01049D
_journal_volume                  5
_journal_year                    2018
_chemical_formula_sum            'C24 H22 S6 Si2'
_chemical_formula_weight         558.96
_space_group_IT_number           15
_space_group_name_Hall           '-C 2yc'
_space_group_name_H-M_alt        'C 1 2/c 1'
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_H-M   'C 1 2/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_audit_update_record
;
2017-11-23 deposited with the CCDC.
2018-02-06 downloaded from the CCDC.
;
_cell_angle_alpha                90.00
_cell_angle_beta                 93.503(6)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   31.277(9)
_cell_length_b                   16.691(5)
_cell_length_c                   10.668(3)
_cell_measurement_reflns_used    2936
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      23.08
_cell_measurement_theta_min      2.33
_cell_volume                     5559(3)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0661
_diffrn_reflns_av_sigmaI/netI    0.0770
_diffrn_reflns_limit_h_max       37
_diffrn_reflns_limit_h_min       -29
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            13684
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         25.00
_diffrn_reflns_theta_min         1.38
_exptl_absorpt_coefficient_mu    0.590
_exptl_absorpt_correction_T_max  0.9063
_exptl_absorpt_correction_T_min  0.7854
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.336
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             2320
_exptl_crystal_size_max          0.43
_exptl_crystal_size_mid          0.26
_exptl_crystal_size_min          0.17
_refine_diff_density_max         0.656
_refine_diff_density_min         -0.523
_refine_diff_density_rms         0.092
_refine_ls_extinction_coef       0.00077(17)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.046
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     290
_refine_ls_number_reflns         4896
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.046
_refine_ls_R_factor_all          0.1099
_refine_ls_R_factor_gt           0.0642
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0581P)^2^+13.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1494
_refine_ls_wR_factor_ref         0.1644
_reflns_number_gt                3019
_reflns_number_total             4896
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            c7qo01049d2.cif
_cod_data_source_block           1
_cod_depositor_comments
;
The following automatic conversions were performed:

data item '_exptl_absorpt_correction_type' value 'Multi-scan' was
changed to 'multi-scan' in accordance with the
/home/saulius/struct/COD-crude-data/automatic-downloads/DataCite-retrospective/RSC/depositions/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 last updated on
2011-04-26.

data item '_symmetry_cell_setting' value 'Monoclinic' was changed to
'monoclinic' in accordance with the
/home/saulius/struct/COD-crude-data/automatic-downloads/DataCite-retrospective/RSC/depositions/lib/dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.2 last updated on
2011-04-26.

Automatic conversion script
Id: cif_fix_values 6909 2019-04-08 15:41:33Z antanas 
;
_cod_original_sg_symbol_H-M      'C2/c  '
_cod_database_code               1553952