3,3,6,6-Tetramethyl-9-phenyl-3,4,5,6-tetrahydro-9<i>H</i>-xanthene-1,8(2<i>H</i>,7<i>H</i>)-dione
Reddy, B. Palakshi; Vijayakumar, V.; Narasimhamurthy, T.; Suresh, J.; Lakshman, P. L. Nilantha; Acta Crystallographica Section E 65 (2009) o916–; doi:10.1107/S1600536809010526

data_2221255
_publ_section_title
3,3,6,6-Tetramethyl-9-phenyl-3,4,5,6-tetrahydro-9<i>H</i>-xanthene-1,8(2<i>H</i>,7<i>H</i>)-dione
_journal_coeditor_code           AT2748
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o916
_journal_paper_doi               10.1107/S1600536809010526
_journal_volume                  65
_journal_year                    2009
_chemical_formula_iupac          'C23 H26 O3'
_chemical_formula_moiety         'C23 H26 O3'
_chemical_formula_sum            'C23 H26 O3'
_chemical_formula_weight         350.44
_chemical_name_systematic
;
3,3,6,6-Tetramethyl-9-phenyl-3,4,5,6-tetrahydro-9<i>H</i>-xanthene-
1,8(2<i>H</i>,7<i>H</i>)-dione
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_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                 97.924(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   6.0562(5)
_cell_length_b                   19.7680(18)
_cell_length_c                   16.4325(13)
_cell_measurement_reflns_used    2500
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      27
_cell_measurement_theta_min      2
_cell_volume                     1948.5(3)
_computing_cell_refinement       'SAINT (Bruker, 2001)'
_computing_data_collection       'SMART (Bruker, 2001)'
_computing_data_reduction        'SAINT (Bruker, 2001)'
_computing_molecular_graphics    'PLATON (Spek, 2009)'
_computing_publication_material  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS (Sheldrick, 2008)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_diffrn_measurement_device_type  'Bruker SMART APEX CCD'
_diffrn_measurement_method       \w
_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  0.0352
_diffrn_reflns_av_sigmaI/netI    0.0423
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       25
_diffrn_reflns_limit_k_min       -25
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -21
_diffrn_reflns_number            11861
_diffrn_reflns_theta_full        27.10
_diffrn_reflns_theta_max         27.10
_diffrn_reflns_theta_min         1.62
_diffrn_standards_decay_%        0
_exptl_absorpt_coefficient_mu    0.077
_exptl_absorpt_correction_T_max  0.992
_exptl_absorpt_correction_T_min  0.987
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Bruker, 1998)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.195
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             752
_exptl_crystal_size_max          0.17
_exptl_crystal_size_mid          0.15
_exptl_crystal_size_min          0.11
_refine_diff_density_max         0.166
_refine_diff_density_min         -0.196
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.034
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     239
_refine_ls_number_reflns         4284
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.034
_refine_ls_R_factor_all          0.0801
_refine_ls_R_factor_gt           0.0495
_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^)+(0.0661P)^2^+0.1411P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1210
_refine_ls_wR_factor_ref         0.1379
_reflns_number_gt                2825
_reflns_number_total             4284
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            at2748.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2221255
_cod_database_fobs_code          2221255