2-Bromobenz[<i>a</i>]anthracene-5,6,7,12-tetraone-5-dimethylketal
Usman, Anwar; Razak, Ibrahim Abdul; Chantrapromma, Suchada; Fun, Hoong-Kun; Dey, Satyajit; Mal, Dipakranjan; Nigam, Gur Dayal; Acta Crystallographica Section E 57 (2001) o825–o826; doi:10.1107/S1600536801012892

data_2200450
_publ_section_title
;
 2-Bromobenz[<i>a</i>]anthracene-5,6,7,12-tetraone-5-dimethylketal
;
_journal_issue                   9
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o825
_journal_page_last               o826
_journal_paper_doi               10.1107/S1600536801012892
_journal_volume                  57
_journal_year                    2001
_chemical_formula_iupac          'C20 H13 Br O5'
_chemical_formula_moiety         'C20 H13 Br O5'
_chemical_formula_sum            'C20 H13 Br O5'
_chemical_formula_weight         413.21
_chemical_melting_point          478
_chemical_name_systematic
;
2-Bromo-5,5-dimethoxybenzo[a]anthracene-6,7,12(5H)trione
;
_space_group_IT_number           2
_symmetry_cell_setting           triclinic
_symmetry_space_group_name_Hall  '-P 1'
_symmetry_space_group_name_H-M   'P -1'
_audit_creation_method           SHELXL97
_cell_angle_alpha                74.4150(10)
_cell_angle_beta                 78.8350(10)
_cell_angle_gamma                81.1920(10)
_cell_formula_units_Z            2
_cell_length_a                   7.74140(10)
_cell_length_b                   10.30840(10)
_cell_length_c                   10.9583(2)
_cell_measurement_reflns_used    3602
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      28.30
_cell_measurement_theta_min      1.95
_cell_volume                     821.65(2)
_computing_cell_refinement       'SAINT (Siemens, 1996)'
_computing_data_collection       'SMART (Siemens, 1996)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    SHELXTL
_computing_publication_material
'SHELXTL, PARST (Nardelli, 1995) and PLATON (Spek, 1990)'
_computing_structure_refinement  SHELXTL
_computing_structure_solution    'SHELXTL (Sheldrick, 1997)'
_diffrn_ambient_temperature      293(2)
_diffrn_detector_area_resol_mean 8.33
_diffrn_measured_fraction_theta_full .96
_diffrn_measured_fraction_theta_max .96
_diffrn_measurement_device_type  'Siemens SMART CCD'
_diffrn_measurement_method       \w
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     .71073
_diffrn_reflns_av_R_equivalents  .055
_diffrn_reflns_av_sigmaI/netI    .107
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            5992
_diffrn_reflns_theta_full        28.3
_diffrn_reflns_theta_max         28.28
_diffrn_reflns_theta_min         1.95
_diffrn_standards_decay_%        0
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    2.532
_exptl_absorpt_correction_T_max  .786
_exptl_absorpt_correction_T_min  .463
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 1996)'
_exptl_crystal_colour            brown-red
_exptl_crystal_density_diffrn    1.670
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       slab
_exptl_crystal_F_000             416
_exptl_crystal_size_max          .36
_exptl_crystal_size_mid          .26
_exptl_crystal_size_min          .10
_refine_diff_density_max         .97
_refine_diff_density_min         -1.79
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   .94
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     237
_refine_ls_number_reflns         3910
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      .94
_refine_ls_R_factor_all          .092
_refine_ls_R_factor_gt           .066
_refine_ls_shift/su_max          <0.001
_refine_ls_shift/su_mean         <0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0817P)^2^] where P = (Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_ref         .165
_reflns_number_gt                2584
_reflns_number_total             3910
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            ci6048.cif
_cod_data_source_block           I
_cod_database_code               2200450
_cod_database_fobs_code          2200450