1-Acetyl-2a,8b-dichloro-1-methoxy-1,2,2a,8b-tetrahydro-3<i>H</i>-cyclobuta[<i>c</i>]chromen-3-one
Zhi-Feng Lu; Hui-Ying An; Wen-Jie Wang; Shan Lu; Jian-Hua Xu; Acta Crystallographica Section E 62 (2006) o177–o178; doi:10.1107/S1600536805040948

data_2207720
_publ_section_title
1-Acetyl-2a,8b-dichloro-1-methoxy-1,2,2a,8b-tetrahydro-3<i>H</i>-cyclobuta[<i>c</i>]chromen-3-one
_journal_coeditor_code           AT6066
_journal_issue                   1
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o177
_journal_page_last               o178
_journal_paper_doi               10.1107/S1600536805040948
_journal_volume                  62
_journal_year                    2006
_chemical_formula_iupac          'C14 H12 Cl2 O4'
_chemical_formula_moiety         'C14 H12 Cl2 O4'
_chemical_formula_sum            'C14 H12 Cl2 O4'
_chemical_formula_weight         315.14
_chemical_melting_point          467.2
_chemical_name_systematic
;
1-Acetyl-2a,8b-dichloro-1-methoxy-1,2,2a,8b-tetrahydro-3H-
cyclobuta[c]chromen-3-one
;
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.00
_cell_angle_beta                 107.09(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   12.678(3)
_cell_length_b                   8.7360(17)
_cell_length_c                   13.185(3)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      25.98
_cell_measurement_theta_min      1.96
_cell_volume                     1395.8(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      293(2)
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.995
_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  0.0514
_diffrn_reflns_av_sigmaI/netI    0.0538
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       0
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       0
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            2851
_diffrn_reflns_theta_full        25.98
_diffrn_reflns_theta_max         25.98
_diffrn_reflns_theta_min         1.96
_diffrn_standards_decay_%        0
_diffrn_standards_interval_count 200
_diffrn_standards_interval_time  120
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.474
_exptl_absorpt_correction_T_max  0.876
_exptl_absorpt_correction_T_min  0.813
_exptl_absorpt_correction_type   psi-scan
_exptl_absorpt_process_details   '(XCAD4; Harms & Wocadlo, 1995)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.500
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             648
_exptl_crystal_size_max          0.43
_exptl_crystal_size_mid          0.33
_exptl_crystal_size_min          0.28
_refine_diff_density_max         0.326
_refine_diff_density_min         -0.304
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.001
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     181
_refine_ls_number_reflns         2727
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.001
_refine_ls_R_factor_all          0.0833
_refine_ls_R_factor_gt           0.0462
_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^)+(0.0637P)^2^+P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1143
_refine_ls_wR_factor_ref         0.1398
_reflns_number_gt                1870
_reflns_number_total             2727
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            at6066.cif
_cod_data_source_block           I
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               2207720
_cod_database_fobs_code          2207720