2-Methyl-2-(trimethylsilyloxy)-3,4-dihydro-2<i>H</i>,5<i>H</i>-pyrano[3,2-<i>c</i>][1]benzopyran-5-one
Da-Quan Peng; Yun Liu; Zhi-Feng Lu; Jian-Hua Xu; Acta Crystallographica Section E 61 (2005) o3704–o3705; doi:10.1107/S1600536805032186

data_2207358
_publ_section_title
2-Methyl-2-(trimethylsilyloxy)-3,4-dihydro-2<i>H</i>,5<i>H</i>-pyrano[3,2-<i>c</i>][1]benzopyran-5-one
_journal_coeditor_code           TK6268
_journal_issue                   11
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o3704
_journal_page_last               o3705
_journal_paper_doi               10.1107/S1600536805032186
_journal_volume                  61
_journal_year                    2005
_chemical_formula_iupac          'C16 H20 O4 Si'
_chemical_formula_moiety         'C16 H20 O4 Si'
_chemical_formula_sum            'C16 H20 O4 Si'
_chemical_formula_weight         304.41
_chemical_melting_point          425.2
_chemical_name_systematic
;
2-Methyl-2-(trimethylsilyloxy)-3,4-dihydro-2H,5H-pyrano[3,2-c][1]benzopyran-
5-one
;
_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
_cell_angle_alpha                90
_cell_angle_beta                 105.09(3)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   11.960(2)
_cell_length_b                   10.456(2)
_cell_length_c                   13.039(3)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    288(2)
_cell_measurement_theta_max      13
_cell_measurement_theta_min      10
_cell_volume                     1574.4(6)
_computing_cell_refinement       'CAD-4 Software'
_computing_data_collection       'CAD-4 Software (Enraf--Nonius, 1989)'
_computing_data_reduction        'XCAD4 (Harms & Wocadlo, 1995)'
_computing_molecular_graphics    SHELXTL
_computing_publication_material  'SHELXTL and PLATON (Spek, 2003)'
_computing_structure_refinement  SHELXTL
_computing_structure_solution    'SHELXTL (Sheldrick, 1997)'
_diffrn_ambient_temperature      288(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Enraf--Nonius CAD-4'
_diffrn_measurement_method       \w/2\q
_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  0.028
_diffrn_reflns_av_sigmaI/netI    0.060
_diffrn_reflns_limit_h_max       14
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            3075
_diffrn_reflns_theta_full        25.5
_diffrn_reflns_theta_max         25.5
_diffrn_reflns_theta_min         1.8
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 200
_diffrn_standards_interval_time  120
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.162
_exptl_absorpt_correction_T_max  0.956
_exptl_absorpt_correction_T_min  0.922
_exptl_absorpt_correction_type   psi-scan
_exptl_absorpt_process_details   '(XCAD4; Harms & Wocadlo, 1995)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.284
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             648
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.31
_exptl_crystal_size_min          0.28
_refine_diff_density_max         0.29
_refine_diff_density_min         -0.25
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.00
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     190
_refine_ls_number_reflns         2930
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.00
_refine_ls_R_factor_all          0.098
_refine_ls_R_factor_gt           0.053
_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^)+(0.055P)^2^+1.48P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.139
_refine_ls_wR_factor_ref         0.152
_reflns_number_gt                1878
_reflns_number_total             2930
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            tk6268.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2207358
_cod_database_fobs_code          2207358