Traceless Directing Groups in Radical Cascades: From Oligoalkynes to Fused Helicenes without Tethered Initiators.
Pati, Kamalkishore; Dos Passos Gomes, Gabriel; Harris, Trevor; Hughes, Audrey; Phan, Hoa; Banerjee, Tanmay; Hanson, Kenneth; Alabugin, Igor V.; Journal of the American Chemical Society 137 (2015) 1165–1180; doi:10.1021/ja510563d

data_4123262
_publ_section_title
;
 Traceless Directing Groups in Radical Cascades: From Oligoalkynes to
 Fused Helicenes without Tethered Initiators.
;
_journal_issue                   3
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              1165
_journal_page_last               1180
_journal_paper_doi               10.1021/ja510563d
_journal_volume                  137
_journal_year                    2015
_chemical_absolute_configuration rm
_chemical_formula_moiety         'C23 H16'
_chemical_formula_sum            'C23 H16'
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_space_group_name_Hall           'P 2yb'
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_symmetry_space_group_name_H-M   'P 1 21 1'
_atom_sites_solution_hydrogens   geom
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_atom_sites_solution_secondary   difmap
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_cell_angle_alpha                90.00
_cell_angle_beta                 108.9180(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   10.4301(14)
_cell_length_b                   6.0297(8)
_cell_length_c                   12.7142(17)
_cell_measurement_temperature    100(2)
_cell_volume                     756.41(18)
_computing_cell_refinement       'Saint V8.27(Bruker AXS, 2011)'
_computing_data_collection       'Apex2 V2012.12-0(Bruker AXS, 2012'
_computing_data_reduction        'Saint V8.27(Bruker AXS, 2011)'
_computing_molecular_graphics    'X-Seed (Barbour, 2001)'
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_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  0.0146
_diffrn_reflns_av_sigmaI/netI    0.0168
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       7
_diffrn_reflns_limit_k_min       -7
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            8435
_diffrn_reflns_theta_full        27.24
_diffrn_reflns_theta_max         27.24
_diffrn_reflns_theta_min         1.69
_exptl_absorpt_coefficient_mu    0.073
_exptl_absorpt_correction_T_max  0.9935
_exptl_absorpt_correction_T_min  0.9310
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'SADABS v2012/1(Bruker, 2012)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.284
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             308
_exptl_crystal_size_max          1.00
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.09
_refine_diff_density_max         0.340
_refine_diff_density_min         -0.171
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_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -2(10)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.056
_refine_ls_hydrogen_treatment    mixed
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_refine_ls_number_reflns         3435
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.056
_refine_ls_R_factor_all          0.0413
_refine_ls_R_factor_gt           0.0399
_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^)+(0.0649P)^2^+0.2059P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1060
_refine_ls_wR_factor_ref         0.1075
_reflns_number_gt                3338
_reflns_number_total             3435
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja510563d_si_002.cif
_cod_data_source_block
;
;
_cod_depositor_comments
'Adding full bibliography for 4123261--4123264.cif.'
_cod_original_cell_volume        756.41(17)
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               4123262