Highly enantioselective nitrone cycloadditions with 2-alkenoyl pyridine N-oxides catalyzed by Cu(II)-BOX complexes.
Barroso, Santiago; Blay, Gonzalo; Muñoz, M Carmen; Pedro, José R; Organic letters 13 (2011) 402–405; doi:10.1021/ol102716e

data_1501894
_publ_section_title
;
 Highly enantioselective nitrone cycloadditions with 2-alkenoyl pyridine
 N-oxides catalyzed by Cu(II)-BOX complexes.
;
_journal_issue                   3
_journal_name_full               'Organic letters'
_journal_page_first              402
_journal_page_last               405
_journal_paper_doi               10.1021/ol102716e
_journal_volume                  13
_journal_year                    2011
_chemical_absolute_configuration ad
_chemical_formula_sum            'C25 H20 N2 O3 S'
_chemical_formula_weight         428.49
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 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                   8.0070(2)
_cell_length_b                   15.0220(6)
_cell_length_c                   17.4870(7)
_cell_measurement_temperature    293(2)
_cell_volume                     2103.36(13)
_computing_cell_refinement       'HKL DENZO'
_computing_data_collection       COLLECT
_computing_data_reduction        'HKL DENZO and SCALEPACK'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    SHELXS-97
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.975
_diffrn_measured_fraction_theta_max 0.975
_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  0.0520
_diffrn_reflns_av_sigmaI/netI    0.0378
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       22
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            16102
_diffrn_reflns_theta_full        27.52
_diffrn_reflns_theta_max         27.52
_diffrn_reflns_theta_min         2.70
_exptl_absorpt_coefficient_mu    0.184
_exptl_absorpt_correction_T_max  0.9963
_exptl_absorpt_correction_T_min  0.9890
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'Empirical absorption correction:XABS2'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.353
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prismatic
_exptl_crystal_F_000             896
_exptl_crystal_size_max          0.06
_exptl_crystal_size_mid          0.02
_exptl_crystal_size_min          0.02
_refine_diff_density_max         0.305
_refine_diff_density_min         -0.362
_refine_diff_density_rms         0.051
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.10(12)
_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   0.973
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     294
_refine_ls_number_reflns         4657
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.973
_refine_ls_R_factor_all          0.0722
_refine_ls_R_factor_gt           0.0500
_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^)+(0.1201P)^2^+0.0977P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1409
_refine_ls_wR_factor_ref         0.1678
_reflns_number_gt                3469
_reflns_number_total             4657
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol102716e_si_002.cif
_cod_data_source_block           gonzalo10-def
_cod_original_sg_symbol_H-M      P212121
_cod_database_code               1501894