3,4-Dihydroxy-1,6-bis(4-methoxyphenyl)hexa-2,4-diene-1,6-dione, its 4-methylphenyl analogue, and a potassium salt of 2-hydroxy-4-(4-methoxyphenyl)-4-oxobut-2-enoic acid
Nye, Luke; Turnbull, Mark M.; Wikaira, Jan L.; Acta Crystallographica Section C 69 (2013) 1317–1321; doi:10.1107/S0108270113025973

data_2019246
_publ_section_title
;
 3,4-Dihydroxy-1,6-bis(4-methoxyphenyl)hexa-2,4-diene-1,6-dione, its
 4-methylphenyl analogue, and a potassium salt of
 2-hydroxy-4-(4-methoxyphenyl)-4-oxobut-2-enoic acid
;
_journal_coeditor_code           MX3105
_journal_issue                   11
_journal_name_full               'Acta Crystallographica Section C'
_journal_page_first              1317
_journal_page_last               1321
_journal_paper_doi               10.1107/S0108270113025973
_journal_volume                  69
_journal_year                    2013
_chemical_formula_iupac          'C20 H18 O6'
_chemical_formula_moiety         'C20 H18 O6'
_chemical_formula_sum            'C20 H18 O6'
_chemical_formula_weight         354.34
_chemical_name_systematic
;
3,4-Dihydroxy-1,6-bis(4-methoxyphenyl)hexa-2,4-diene-1,6-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   difmap
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL97
_cell_angle_alpha                90.00
_cell_angle_beta                 105.029(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   15.4385(6)
_cell_length_b                   6.1475(2)
_cell_length_c                   8.7281(3)
_cell_measurement_reflns_used    6419
_cell_measurement_temperature    116(2)
_cell_measurement_theta_max      30.37
_cell_measurement_theta_min      2.73
_cell_volume                     800.03(5)
_computing_cell_refinement       'SHELXTL (Sheldrick, 2008)'
_computing_data_collection       'SHELXTL (Sheldrick, 2008)'
_computing_data_reduction        'SHELXTL (Sheldrick, 2008)'
_computing_molecular_graphics
;
SHELXTL (Sheldrick, 2008) and Mercury (Macrae <i>et al.</i>,
2008)
;
_computing_publication_material
;
SHELXL97 (Sheldrick, 2008), enCIFer (Allen <i>et al.</i>, 2004)
and
publCIF (Westrip 2010)
;
_computing_structure_refinement  'SHELXL97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      116(2)
_diffrn_measured_fraction_theta_full 0.988
_diffrn_measured_fraction_theta_max 0.988
_diffrn_measurement_device_type  'Bruker APEXII CCD area-detector'
_diffrn_measurement_method       '\f and \w 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  0.0291
_diffrn_reflns_av_sigmaI/netI    0.0181
_diffrn_reflns_limit_h_max       21
_diffrn_reflns_limit_h_min       -20
_diffrn_reflns_limit_k_max       8
_diffrn_reflns_limit_k_min       -8
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            16170
_diffrn_reflns_theta_full        30.03
_diffrn_reflns_theta_max         30.03
_diffrn_reflns_theta_min         2.73
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.109
_exptl_absorpt_correction_T_max  0.9870
_exptl_absorpt_correction_T_min  0.9425
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   '(SADABS; Sheldrick, 1996)'
_exptl_crystal_colour            yellow
_exptl_crystal_density_diffrn    1.471
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             372
_exptl_crystal_size_max          0.55
_exptl_crystal_size_mid          0.33
_exptl_crystal_size_min          0.12
_refine_diff_density_max         0.361
_refine_diff_density_min         -0.324
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.120
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     122
_refine_ls_number_reflns         2313
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.120
_refine_ls_R_factor_all          0.0466
_refine_ls_R_factor_gt           0.0430
_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^)+(0.0523P)^2^+0.2726P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1106
_refine_ls_wR_factor_ref         0.1131
_reflns_number_gt                2155
_reflns_number_total             2313
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            mx3105.cif
_cod_data_source_block           compound1
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               2019246