Enantioselective synthesis utilizing enantiomorphous organic crystal of achiral benzils as a source of chirality in asymmetric autocatalysis.
Kawasaki, Tsuneomi; Harada, Yuuki; Suzuki, Kenta; Tobita, Takayuki; Florini, Nicola; Pályi, Gyula; Soai, Kenso; Organic letters 10 (2008) 4085–4088; doi:10.1021/ol801600y

data_1504863
_publ_section_title
;
 Enantioselective synthesis utilizing enantiomorphous organic crystal of
 achiral benzils as a source of chirality in asymmetric autocatalysis.
;
_journal_issue                   18
_journal_name_full               'Organic letters'
_journal_page_first              4085
_journal_page_last               4088
_journal_paper_doi               10.1021/ol801600y
_journal_volume                  10
_journal_year                    2008
_chemical_formula_sum            'C14 H8 Br2 O2'
_chemical_formula_weight         368.02
_space_group_IT_number           18
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2 2ab'
_symmetry_space_group_name_H-M   'P 21 21 2'
_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            2
_cell_length_a                   5.9307(12)
_cell_length_b                   26.138(6)
_cell_length_c                   3.9251(8)
_cell_measurement_reflns_used    2046
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      27.80
_cell_measurement_theta_min      3.12
_cell_volume                     608.5(2)
_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_detector_area_resol_mean 8.366
_diffrn_measured_fraction_theta_full 0.963
_diffrn_measured_fraction_theta_max 0.963
_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  0.0548
_diffrn_reflns_av_sigmaI/netI    0.0525
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -33
_diffrn_reflns_limit_l_max       5
_diffrn_reflns_limit_l_min       -4
_diffrn_reflns_number            3486
_diffrn_reflns_theta_full        27.83
_diffrn_reflns_theta_max         27.83
_diffrn_reflns_theta_min         1.56
_exptl_absorpt_coefficient_mu    6.650
_exptl_absorpt_correction_T_max  0.6532
_exptl_absorpt_correction_T_min  0.1713
_exptl_absorpt_correction_type   analytical
_exptl_absorpt_process_details   analytical
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    2.009
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             356
_exptl_crystal_size_max          0.41
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.07
_refine_diff_density_max         2.398
_refine_diff_density_min         -1.290
_refine_diff_density_rms         0.214
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.03(4)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.178
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     82
_refine_ls_number_reflns         1352
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.178
_refine_ls_R_factor_all          0.0526
_refine_ls_R_factor_gt           0.0495
_refine_ls_shift/su_max          0.008
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0789P)^2^+1.4842P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1377
_refine_ls_wR_factor_ref         0.1388
_reflns_number_gt                1265
_reflns_number_total             1352
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol801600y_si_002.cif
_cod_data_source_block           brbenzil
_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_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_cell_volume        608.4(2)
_cod_original_sg_symbol_H-M      P2(1)2(1)2
_cod_database_code               1504863