Diastereoselective photodimerization reactions of chromone-2-carboxamides to construct a C2-chiral scaffold.
Yagishita, Fumitoshi; Baba, Nozomi; Ueda, Yuki; Katabira, Satoshi; Kasashima, Yoshio; Mino, Takashi; Sakamoto, Masami; Organic & biomolecular chemistry 12 (2014) 9644–9649; doi:10.1039/c4ob01827c

data_7154130
_publ_section_title
;
 Diastereoselective photodimerization reactions of chromone-2-carboxamides
 to construct a C2-chiral scaffold.
;
_journal_issue                   47
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              9644
_journal_page_last               9649
_journal_paper_doi               10.1039/c4ob01827c
_journal_volume                  12
_journal_year                    2014
_chemical_absolute_configuration rm
_chemical_formula_sum            'C32 H38 N2 O6'
_chemical_formula_weight         546.64
_chemical_melting_point          531.5(5)
_chemical_name_systematic
'Anti-HH photodimer of (R)-N-(1-t-butylethyl)-2-chromonecarboxamide'
_space_group_crystal_system      orthorhombic
_space_group_IT_number           19
_space_group_name_Hall           'P 2ac 2ab'
_space_group_name_H-M_alt        'P 21 21 21'
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2013
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   7.704(18)
_cell_length_b                   14.23(3)
_cell_length_c                   26.50(6)
_cell_measurement_temperature    173(2)
_cell_volume                     2905(11)
_computing_structure_refinement  'SHELXL-2013 (Sheldrick, 2013)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.995
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0562
_diffrn_reflns_av_unetI/netI     0.0800
_diffrn_reflns_Laue_measured_fraction_full 0.997
_diffrn_reflns_Laue_measured_fraction_max 0.995
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       32
_diffrn_reflns_limit_l_min       -26
_diffrn_reflns_number            13455
_diffrn_reflns_point_group_measured_fraction_full 0.992
_diffrn_reflns_point_group_measured_fraction_max 0.989
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         25.614
_diffrn_reflns_theta_min         1.537
_exptl_absorpt_coefficient_mu    0.086
_exptl_crystal_density_diffrn    1.249
_exptl_crystal_F_000             1168
_exptl_crystal_recrystallization_method
'Re-crystallisation from solvent: CHCl3/hexane'
_exptl_crystal_size_max          0.300
_exptl_crystal_size_mid          0.300
_exptl_crystal_size_min          0.200
_refine_diff_density_max         0.742
_refine_diff_density_min         -0.398
_refine_diff_density_rms         0.127
_refine_ls_abs_structure_details
;
 Flack x determined using 1016 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons and Flack (2004), Acta Cryst. A60, s61).
;
_refine_ls_abs_structure_Flack   -1.6(9)
_refine_ls_extinction_coef       0.023(3)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.006
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     370
_refine_ls_number_reflns         5433
_refine_ls_number_restraints     114
_refine_ls_restrained_S_all      0.997
_refine_ls_R_factor_all          0.1081
_refine_ls_R_factor_gt           0.0629
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.1030P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1531
_refine_ls_wR_factor_ref         0.1907
_reflns_Friedel_coverage         0.741
_reflns_Friedel_fraction_full    0.986
_reflns_Friedel_fraction_max     0.980
_reflns_number_gt                3321
_reflns_number_total             5433
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c4ob01827c2.cif
_cod_data_source_block           saka493_P212121_a
_cod_depositor_comments
;
The following automatic conversions were performed:

'_chemical_melting_point' value '531-532' was changed to '531.5(5)' -
the average value was taken and precision was estimated.

Automatic conversion script
Id: cif_fix_values 2827 2014-09-09 07:05:25Z andrius 

 Adding full bibliography for 7154126--7154132.cif.
;
_cod_original_cell_volume        2906(11)
_cod_database_code               7154130
_shelx_estimated_absorpt_t_min   0.975
_shelx_estimated_absorpt_t_max   0.983
_shelxl_version_number           2013-3
_shelx_res_checksum              86166
_shelx_hkl_checksum              88990