Dynamic kinetic resolution in the asymmetric synthesis of atropisomeric biaryl[4] and [5]helicene quinones.
Latorre, Alfonso; Urbano, Antonio; Carreño, M Carmen; Chemical communications (Cambridge, England)  (2009) 6652–6654; doi:10.1039/b907653k

data_7104971
_publ_section_title
;
 Dynamic kinetic resolution in the asymmetric synthesis of
 atropisomeric biaryl[4] and [5]helicene quinones.
;
_journal_issue                   43
_journal_name_full               'Chemical communications (Cambridge, England)'
_journal_page_first              6652
_journal_page_last               6654
_journal_paper_doi               10.1039/b907653k
_journal_year                    2009
_chemical_formula_sum            'C36 H28 O3'
_chemical_formula_weight         508.58
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.6471(4)
_cell_length_b                   15.5793(9)
_cell_length_c                   21.7870(13)
_cell_measurement_reflns_used    9826
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      28.62
_cell_measurement_theta_min      2.28
_cell_volume                     2595.6(3)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega 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  0.0507
_diffrn_reflns_av_sigmaI/netI    0.0191
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            106248
_diffrn_reflns_theta_full        26.73
_diffrn_reflns_theta_max         26.73
_diffrn_reflns_theta_min         1.87
_exptl_absorpt_coefficient_mu    0.082
_exptl_absorpt_correction_T_max  0.9879
_exptl_absorpt_correction_T_min  0.9681
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS (Sheldrick, 2001)'
_exptl_crystal_colour            orange
_exptl_crystal_density_diffrn    1.301
_exptl_crystal_density_meas      0
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prismatic
_exptl_crystal_F_000             1072
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.279
_refine_diff_density_min         -0.303
_refine_diff_density_rms         0.117
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.1(9)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.114
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     464
_refine_ls_number_reflns         5503
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.114
_refine_ls_R_factor_all          0.0393
_refine_ls_R_factor_gt           0.0308
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0447P)^2^+0.5926P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0786
_refine_ls_wR_factor_ref         0.0854
_reflns_number_gt                4950
_reflns_number_total             5503
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            b907653k.txt
_cod_data_source_block           datos_0m
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 
;
_cod_original_sg_symbol_H-M      P2(1)2(1)2(1)
_cod_database_code               7104971