First asymmetric desymmetrisation of a centrosymmetric molecule: CBS reduction of a 2-pyridone [4 + 4]-photodimer derivative
Spivey, Alan C.; Andrews, Benjamin I.; Brown, Alan D.; Frampton, Christopher S.; Chemical Communications  (1999) 2523–; doi:10.1039/a908059g

data_7110744
_publ_section_title
;
 First asymmetric desymmetrisation of a centrosymmetric molecule: CBS
 reduction of a 2-pyridone [4 + 4]-photodimer derivative
;
_journal_issue                   24
_journal_name_full               'Chemical Communications'
_journal_page_first              2523
_journal_paper_doi               10.1039/a908059g
_journal_year                    1999
_chemical_formula_moiety         'C20 H32 N2 O6'
_chemical_formula_sum            'C20 H32 N2 O6'
_chemical_formula_weight         396.48
_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                 112.63(4)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   6.332(4)
_cell_length_b                   26.000(4)
_cell_length_c                   6.720(3)
_cell_measurement_reflns_used    25
_cell_measurement_temperature    123(1)
_cell_measurement_theta_max      54.9
_cell_measurement_theta_min      53.1
_cell_volume                     1021.1(9)
_computing_cell_refinement       'Rigaku/AFC Diffractometer Control'
_computing_data_collection       'Rigaku/AFC Diffractometer Control'
_computing_data_reduction        teXsan
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      123(1)
_diffrn_measured_fraction_theta_full 0.983
_diffrn_measured_fraction_theta_max 0.983
_diffrn_measurement_device_type  'Rigaku AFC7R'
_diffrn_measurement_method       \w-2\q
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'Rigaku RU200 Rotating Cu Anode'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0140
_diffrn_reflns_av_sigmaI/netI    0.0087
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       31
_diffrn_reflns_limit_k_min       -31
_diffrn_reflns_limit_l_max       7
_diffrn_reflns_limit_l_min       -7
_diffrn_reflns_number            4008
_diffrn_reflns_theta_full        67.45
_diffrn_reflns_theta_max         67.45
_diffrn_reflns_theta_min         3.40
_diffrn_standards_decay_%        2.32
_diffrn_standards_interval_count 150
_diffrn_standards_number         3
_exptl_absorpt_coefficient_mu    0.781
_exptl_absorpt_correction_T_max  0.999
_exptl_absorpt_correction_T_min  0.916
_exptl_absorpt_correction_type   '\y scans(North,Phillips & Mathews,1968)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.289
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             428
_exptl_crystal_size_max          0.400
_exptl_crystal_size_mid          0.350
_exptl_crystal_size_min          0.300
_refine_diff_density_max         0.193
_refine_diff_density_min         -0.216
_refine_diff_density_rms         0.049
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.14(19)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.009
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     295
_refine_ls_number_reflns         3589
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.008
_refine_ls_R_factor_all          0.0418
_refine_ls_R_factor_gt           0.0417
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0850P)^2^+0.4000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1177
_refine_ls_wR_factor_ref         0.1177
_reflns_number_gt                3585
_reflns_number_total             3589
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            908059gsup1.cif
_cod_data_source_block           csf104a
_cod_depositor_comments
;
The following automatic conversions were performed:

'_exptl_crystal_density_meas' value 'not measured' was changed to '?'
- the value is perceived as not measured.

Automatic conversion script
Id: cif_fix_values 3008 2015-01-20 13:52:24Z robertas 
;
_cod_original_cell_volume        1021.1(8)
_cod_original_sg_symbol_H-M      'P 21'
_cod_database_code               7110744