Crystal structure and identification of resonance forms of diethyl 2-(3-oxoiso-1,3-di-hydro-benzo-furan-1-yl-idene)malonate.
Tyumentsev, Mikhail S.; Foreman, Mark R StJ; Steenari, Britt-Marie; Slawin, Alexandra M. Z.; Acta crystallographica. Section E, Crystallographic communications 73 (2017) 1576–1579; doi:10.1107/S2056989017013962

data_2311455
_publ_section_title
;
 Crystal structure and identification of resonance forms of diethyl
 2-(3-oxoiso-1,3-di-hydro-benzo-furan-1-yl-idene)malonate.
;
_journal_coeditor_code           HB7700
_journal_issue                   'Pt 10'
_journal_name_full
'Acta crystallographica. Section E, Crystallographic communications'
_journal_page_first              1576
_journal_page_last               1579
_journal_paper_doi               10.1107/S2056989017013962
_journal_volume                  73
_journal_year                    2017
_chemical_formula_iupac          'C15 H14 O6'
_chemical_formula_moiety         'C15 H14 O6'
_chemical_formula_sum            'C15 H14 O6'
_chemical_formula_weight         290.27
_chemical_name_systematic
;
Diethyl 2-(3-oxo-1,3-dihydro-2-benzofuran-1-ylidene)propanedioate
;
_space_group_crystal_system      triclinic
_space_group_IT_number           2
_space_group_name_Hall           '-P 1'
_space_group_name_H-M_alt        'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           'by CrystalStructure 4.1'
_cell_angle_alpha                67.706(15)
_cell_angle_beta                 72.228(16)
_cell_angle_gamma                86.41(2)
_cell_formula_units_Z            2
_cell_length_a                   7.942(2)
_cell_length_b                   9.453(3)
_cell_length_c                   10.226(2)
_cell_measurement_reflns_used    2290
_cell_measurement_temperature    93
_cell_measurement_theta_max      27.50
_cell_measurement_theta_min      2.30
_cell_volume                     675.2(3)
_computing_cell_refinement
;
<i>CrystalClear-SM Expert</i> (Rigaku, 2014)
;
_computing_data_collection
;
<i>CrystalClear-SM Expert</i> (Rigaku, 2014)
;
_computing_data_reduction
;
<i>CrystalClear-SM Expert</i> (Rigaku, 2014)
;
_computing_molecular_graphics
;
CrystalStructure (Rigaku, 2014)
;
_computing_publication_material
;
CrystalStructure (Rigaku, 2014)
;
_computing_structure_refinement
;
SHELXL2013 (Sheldrick, 2008)
;
_computing_structure_solution
;
SIR2011 (Burla <i>et al.</i>,  2012)
;
_diffrn_ambient_temperature      93
_diffrn_detector_area_resol_mean 5.814
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.994
_diffrn_measurement_device_type  'Rigaku XtaLAB P200'
_diffrn_measurement_method       \w
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71075
_diffrn_reflns_av_R_equivalents  0.0310
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       12
_diffrn_reflns_limit_l_min       -12
_diffrn_reflns_number            9890
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         25.336
_diffrn_reflns_theta_min         2.260
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.111
_exptl_absorpt_correction_T_max  0.983
_exptl_absorpt_correction_T_min  0.829
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
(<i>REQAB</i>; Rigaku, 1998)
;
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.428
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             304.00
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.15
_refine_diff_density_max         0.25
_refine_diff_density_min         -0.18
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.072
_refine_ls_hydrogen_treatment    constr
_refine_ls_number_parameters     192
_refine_ls_number_reflns         2466
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0297
_refine_ls_R_factor_gt           0.0279
_refine_ls_shift/su_max          0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0425P)^2^+0.0953P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0762
_refine_ls_wR_factor_ref         0.0776
_reflns_number_gt                2278
_reflns_number_total             2466
_reflns_threshold_expression     F^2^>2.0\s(F^2^)
_cod_data_source_file            hb7700sup1.cif
_cod_data_source_block           I
_cod_database_code               2311455
_shelx_hkl_checksum              49469
_shelx_res_checksum              15623