A Facile, General Synthesis of 3,4-Difluoro-6-substituted-2-pyrones
Yi Wang; Donald J. Burton; Journal of Organic Chemistry 71 (2006) 3859–3862; doi:10.1021/jo060362a

data_4021691
_publ_section_title
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 A Facile, General Synthesis of 3,4-Difluoro-6-substituted-2-pyrones
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_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              3859
_journal_page_last               3862
_journal_paper_doi               10.1021/jo060362a
_journal_volume                  71
_journal_year                    2006
_chemical_formula_moiety         'C11 H6 F2 O2'
_chemical_formula_sum            'C11 H6 F2 O2'
_chemical_formula_weight         208.16
_space_group_IT_number           29
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2c -2ac'
_symmetry_space_group_name_H-M   'P c a 21'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   20.703(2)
_cell_length_b                   5.5301(5)
_cell_length_c                   7.6557(8)
_cell_measurement_reflns_used    2034
_cell_measurement_temperature    190(2)
_cell_measurement_theta_max      25.0
_cell_measurement_theta_min      1.0
_cell_volume                     876.50(15)
_computing_cell_refinement       'HKL Scalepack (Otwinowski & Minor, 1997)'
_computing_data_collection       'Collect (Nonius BV, 1997-2000)'
_computing_data_reduction
'HKL Denzo, Scalepack (Otwinowski & Minor, 1997)'
_computing_molecular_graphics    'SHELXTL v6.1 (Sheldrick, 1997)'
_computing_publication_material  'SHELXTL v6.1 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXTL v6.1 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXTL v6.1 (Sheldrick, 1997)'
_diffrn_ambient_temperature      190(2)
_diffrn_detector_area_resol_mean 9
_diffrn_measured_fraction_theta_full 0.959
_diffrn_measured_fraction_theta_max 0.959
_diffrn_measurement_device_type  KappaCCD
_diffrn_measurement_method       'CCD phi and omega 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  0.0461
_diffrn_reflns_av_sigmaI/netI    0.0406
_diffrn_reflns_limit_h_max       24
_diffrn_reflns_limit_h_min       -23
_diffrn_reflns_limit_k_max       6
_diffrn_reflns_limit_k_min       -6
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -6
_diffrn_reflns_number            6680
_diffrn_reflns_theta_full        24.99
_diffrn_reflns_theta_max         25.0
_diffrn_reflns_theta_min         3.3
_exptl_absorpt_coefficient_mu    0.136
_exptl_absorpt_correction_T_max  0.9932
_exptl_absorpt_correction_T_min  0.9413
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'HKL Scalepack (Otwinowski & Minor, 1997)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.577
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       blade
_exptl_crystal_F_000             424
_exptl_crystal_size_max          0.45
_exptl_crystal_size_mid          0.14
_exptl_crystal_size_min          0.05
_refine_diff_density_max         0.159
_refine_diff_density_min         -0.167
_refine_diff_density_rms         0.042
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.091
_refine_ls_hydrogen_treatment    riding
_refine_ls_matrix_type           full
_refine_ls_number_parameters     136
_refine_ls_number_reflns         802
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.090
_refine_ls_R_factor_all          0.0566
_refine_ls_R_factor_gt           0.0422
_refine_ls_shift/su_max          0.006
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0402P)^2^+0.4941P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1002
_refine_ls_wR_factor_ref         0.1058
_reflns_number_gt                670
_reflns_number_total             802
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo060362asi20060224_015310.cif
_cod_depositor_comments
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The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
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 
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_cod_database_code               4021691