Addition of Difluorocarbene to 4',5'-Unsaturated Nucleosides: Synthesis and Deoxygenation Reactions of Difluorospirocyclopropane Nucleosides
Ireneusz Nowak; Morris J. Robins; Journal of Organic Chemistry 71 (2006) 8876–8883; doi:10.1021/jo061606u

data_4022086
_publ_section_title
;
 Addition of Difluorocarbene to 4',5'-Unsaturated Nucleosides:
 Synthesis and Deoxygenation Reactions of
 Difluorospirocyclopropane Nucleosides
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              8876
_journal_page_last               8883
_journal_paper_doi               10.1021/jo061606u
_journal_volume                  71
_journal_year                    2006
_chemical_absolute_configuration unk
_chemical_formula_sum            'C20 H18 F2 N2 O6'
_chemical_formula_weight         420.36
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 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                 114.245(12)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   12.0009(18)
_cell_length_b                   7.0164(10)
_cell_length_c                   12.796(2)
_cell_measurement_reflns_used    39
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      14.65
_cell_measurement_theta_min      4.54
_cell_volume                     982.4(3)
_computing_cell_refinement       'Bruker XSCANS'
_computing_data_collection       'Bruker XSCANS'
_computing_data_reduction        'Bruker SHELXTL'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Bruker P4'
_diffrn_measurement_method       'Theta/2-theta 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  0.0205
_diffrn_reflns_av_sigmaI/netI    0.0315
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -1
_diffrn_reflns_limit_k_max       1
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            3179
_diffrn_reflns_theta_full        27.49
_diffrn_reflns_theta_max         27.49
_diffrn_reflns_theta_min         3.03
_diffrn_standards_interval_count 97
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.118
_exptl_absorpt_correction_T_max  0.9746
_exptl_absorpt_correction_T_min  0.9327
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            COLORLESS
_exptl_crystal_density_diffrn    1.421
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       PLATE
_exptl_crystal_F_000             436
_exptl_crystal_size_max          0.60
_exptl_crystal_size_mid          0.48
_exptl_crystal_size_min          0.22
_refine_diff_density_max         0.154
_refine_diff_density_min         -0.163
_refine_diff_density_rms         0.038
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0(10)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.047
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     273
_refine_ls_number_reflns         2430
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.046
_refine_ls_R_factor_all          0.0406
_refine_ls_R_factor_gt           0.0337
_refine_ls_shift/su_max          0.007
_refine_ls_shift/su_mean         0.001
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0416P)^2^+0.0847P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0834
_refine_ls_wR_factor_ref         0.0872
_reflns_number_gt                2150
_reflns_number_total             2430
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo061606usi20060803_013934.cif
_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 
;
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               4022086