Two tautomers in one crystal structure: ethyl 6(4)-oxo-1,6(1,4)-dihydropyrimidine-5-carboxylate
De-Jun Xiong; Cui-Ping Han; Hai-Bing Li; Acta Crystallographica Section E 62 (2006) o5501–o5502; doi:10.1107/S1600536806045995

data_2211657
_publ_section_title
;
 Two tautomers in one crystal structure: ethyl
 6(4)-oxo-1,6(1,4)-dihydropyrimidine-5-carboxylate
;
_journal_coeditor_code           WN2076
_journal_issue                   12
_journal_name_full               'Acta Crystallographica Section E'
_journal_page_first              o5501
_journal_page_last               o5502
_journal_paper_doi               10.1107/S1600536806045995
_journal_volume                  62
_journal_year                    2006
_chemical_formula_iupac          'C7 H8 N2 O3'
_chemical_formula_moiety         'C7 H8 N2 O3'
_chemical_formula_sum            'C7 H8 N2 O3'
_chemical_formula_weight         168.15
_chemical_name_systematic
;
ethyl 6-oxo-1,6-dihydropyrimidine-5-carboxylate--ethyl
4-oxo-1,4-dihydropyrimidine-5-carboxylate (1/1)
;
_space_group_IT_number           9
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'C -2yc'
_symmetry_space_group_name_H-M   'C 1 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                 97.687(10)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   4.768(3)
_cell_length_b                   25.590(16)
_cell_length_c                   12.821(8)
_cell_measurement_reflns_used    1061
_cell_measurement_temperature    292(2)
_cell_measurement_theta_max      20.23
_cell_measurement_theta_min      2.26
_cell_volume                     1550.3(17)
_computing_cell_refinement       'SAINT (Bruker, 1999)'
_computing_data_collection       'SMART (Bruker, 1997)'
_computing_data_reduction        SAINT
_computing_molecular_graphics    'SHELXTL (Bruker, 2001)'
_computing_publication_material  SHELXTL
_computing_structure_refinement  'SHELXL97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS97 (Sheldrick, 1997)'
_diffrn_ambient_temperature      292(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker SMART APEX CCD'
_diffrn_measurement_method       '\f and \w'
_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  0.0529
_diffrn_reflns_av_sigmaI/netI    0.0555
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -5
_diffrn_reflns_limit_k_max       31
_diffrn_reflns_limit_k_min       -29
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -15
_diffrn_reflns_number            4986
_diffrn_reflns_theta_full        26.00
_diffrn_reflns_theta_max         26.00
_diffrn_reflns_theta_min         1.59
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.115
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.441
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             704
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.10
_exptl_crystal_size_min          0.03
_refine_diff_density_max         0.250
_refine_diff_density_min         -0.168
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.033
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     219
_refine_ls_number_reflns         1526
_refine_ls_number_restraints     4
_refine_ls_restrained_S_all      1.031
_refine_ls_R_factor_all          0.0767
_refine_ls_R_factor_gt           0.0527
_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^)+(0.0587P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1088
_refine_ls_wR_factor_ref         0.1176
_reflns_number_gt                1121
_reflns_number_total             1526
_reflns_threshold_expression     I>2\s(I)
_cod_data_source_file            wn2076.cif
_cod_data_source_block           I
_cod_depositor_comments
;
The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to '/home/saulius/struct/CIF-dictionaries/cif_core.dic'
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_enum 1527 2010-12-29 10:47:43Z saulius 

The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_cell_volume        1550.4(17)
_cod_original_sg_symbol_H-M      'C c'
_cod_database_code               2211657