Methyl 2-(2,2-dimethyl-3a,6a-dihydrofuro[3,2-<i>d</i>][1,3]dioxol-5-yl)-4-oxo-4<i>H</i>-chromene-3-carboxylate
Fatima, Zeenat; Srinivasan, Thothadri; Rao, Jonnalagadda Naga Siva; Raghunathan, Raghavachary; Velmurugan, Devadasan; Acta Crystallographica Section E 69 (2013) o1310–; doi:10.1107/S1600536813019648

data_2238433
_publ_section_title
;
 Methyl
 2-(2,2-dimethyl-3a,6a-dihydrofuro[3,2-<i>d</i>][1,3]dioxol-5-yl)-4-oxo-4<i>H</i>-chromene-3-carboxylate
;
_journal_coeditor_code           SU2622
_journal_issue                   8
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o1310
_journal_paper_doi               10.1107/S1600536813019648
_journal_volume                  69
_journal_year                    2013
_chemical_formula_iupac          'C18 H16 O7'
_chemical_formula_moiety         'C18 H16 O7'
_chemical_formula_sum            'C18 H16 O7'
_chemical_formula_weight         344.31
_chemical_name_systematic
'Methyl 2-(2,2-dimethyl-3a,6a-dihydrofuro[3,2-<i>d</i>][1,3]dioxol-5-yl)-4-oxo-4<i>H</i>-chromene-3-carboxylate'
_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                   6.8875(3)
_cell_length_b                   15.4958(6)
_cell_length_c                   15.9035(6)
_cell_measurement_reflns_used    4131
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      28.33
_cell_measurement_theta_min      1.83
_cell_volume                     1697.34(12)
_computing_cell_refinement       'SAINT (Bruker, 2008)'
_computing_data_collection       'APEX2 (Bruker, 2008)'
_computing_data_reduction        'SAINT (Bruker, 2008)'
_computing_molecular_graphics    'ORTEP-3 for Windows (Farrugia, 2012)'
_computing_publication_material
'SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Bruker SMART APEXII area-detector'
_diffrn_measurement_method       '\w and \f 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  0.0213
_diffrn_reflns_av_sigmaI/netI    0.0298
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -20
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            9565
_diffrn_reflns_theta_full        28.33
_diffrn_reflns_theta_max         28.33
_diffrn_reflns_theta_min         1.83
_exptl_absorpt_coefficient_mu    0.105
_exptl_absorpt_correction_T_max  0.9794
_exptl_absorpt_correction_T_min  0.9693
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(<i>SADABS</i>; Bruker, 2008)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.347
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             720
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.25
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.180
_refine_diff_density_min         -0.188
_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     267
_refine_ls_number_reflns         4131
_refine_ls_number_restraints     99
_refine_ls_restrained_S_all      1.045
_refine_ls_R_factor_all          0.0627
_refine_ls_R_factor_gt           0.0412
_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^)+(0.0575P)^2^+0.0367P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0976
_refine_ls_wR_factor_ref         0.1083
_reflns_number_gt                2983
_reflns_number_total             4131
_reflns_threshold_expression     I>2sigma(I)
_cod_data_source_file            su2622.cif
_cod_data_source_block           I
_cod_database_code               2238433
_cod_database_fobs_code          2238433