Carbonyl–carbonyl, carbonyl–π and carbonyl–halogen dipolar interactions as the directing motifs of the supramolecular structure of ethyl 6-chloro-2-oxo-2<i>H</i>-chromene-3-carboxylate and ethyl 6-bromo-2-oxo-2<i>H</i>-chromene-3-carboxylate
Rocio J. Santos-Contreras; Francisco J. Martínez-Martínez; Efrén V. García-Báez; Itzia I. Padilla-Martínez; Ana L. Peraza; Herbert Höpfl; Acta Crystallographica Section C 63 (2007) o239–o242; doi:10.1107/S0108270107008712

data_2015926
_publ_section_title
;
 Carbonyl--carbonyl, carbonyl--\p and carbonyl--halogen dipolar
 interactions as the directing motifs of the supramolecular structure
 of ethyl 6-chloro-2-oxo-2<i>H</i>-chromene-3-carboxylate and ethyl
 6-bromo-2-oxo-2<i>H</i>-chromene-3-carboxylate
;
_journal_coeditor_code           SU3001
_journal_issue                   4
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              o239
_journal_page_last               o242
_journal_paper_doi               10.1107/S0108270107008712
_journal_volume                  63
_journal_year                    2007
_chemical_formula_iupac          'C12 H9 Br O4'
_chemical_formula_moiety         'C12 H9 Br O4'
_chemical_formula_sum            'C12 H9 Br O4'
_chemical_formula_weight         297.10
_chemical_name_systematic
;
ethyl  6-bromo-2-oxo-2H-chromene-3-carboxylate
;
_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                 109.327(3)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   5.8432(6)
_cell_length_b                   13.2073(14)
_cell_length_c                   15.6959(15)
_cell_measurement_reflns_used    600
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      25
_cell_measurement_theta_min      20
_cell_volume                     1143.0(2)
_computing_cell_refinement       'SAINT (Bruker, 2002)'
_computing_data_collection       'SMART (Bruker, 2002)'
_computing_data_reduction        SAINT
_computing_molecular_graphics
'Mercury (Version 1.4; Bruno <i>et al.</i>,  2002)'
_computing_publication_material  'SHELXL97  and WinGX-2003 (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.965
_diffrn_measurement_device       'Bruker SMART CCD area-detector'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0408
_diffrn_reflns_av_sigmaI/netI    0.0356
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       17
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            12998
_diffrn_reflns_theta_full        25.00
_diffrn_reflns_theta_max         28.32
_diffrn_reflns_theta_min         2.07
_diffrn_standards_decay_%        5
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    3.595
_exptl_absorpt_correction_T_max  0.6722
_exptl_absorpt_correction_T_min  0.4550
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 1996)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.726
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             592
_exptl_crystal_size_max          0.26
_exptl_crystal_size_mid          0.15
_exptl_crystal_size_min          0.12
_refine_diff_density_max         1.004
_refine_diff_density_min         -0.255
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.049
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     155
_refine_ls_number_reflns         2754
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.049
_refine_ls_R_factor_all          0.0612
_refine_ls_R_factor_gt           0.0446
_refine_ls_shift/su_max          <0.001
_refine_ls_shift/su_mean         <0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0647P)^2^+0.4243P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1133
_refine_ls_wR_factor_ref         0.1226
_reflns_number_gt                2091
_reflns_number_total             2754
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            su3001.cif
_cod_data_source_block           II
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2015926
_cod_database_fobs_code          2015926