Proline as Lewis base catalyst: diastereoselective synthesis of isoxazoline-N-oxide through [3 + 2] cycloaddition.
Duan, Haifeng; Sun, Xiaohua; Liao, Wenyan; Petersen, Jeffrey L.; Shi, Xiaodong; Organic letters 10 (2008) 4113–4116; doi:10.1021/ol801656y

data_1504877
_publ_section_title
;
 Proline as Lewis base catalyst: diastereoselective synthesis of
 isoxazoline-N-oxide through [3 + 2] cycloaddition.
;
_journal_issue                   18
_journal_name_full               'Organic letters'
_journal_page_first              4113
_journal_page_last               4116
_journal_paper_doi               10.1021/ol801656y
_journal_volume                  10
_journal_year                    2008
_chemical_formula_sum            'C22 H23 N O2'
_chemical_formula_weight         333.41
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 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                 98.174(1)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   9.7549(7)
_cell_length_b                   15.8328(12)
_cell_length_c                   12.3179(9)
_cell_measurement_reflns_used    5492
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      27.50
_cell_measurement_theta_min      2.46
_cell_volume                     1883.1(2)
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.992
_diffrn_measured_fraction_theta_max 0.992
_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  0.0396
_diffrn_reflns_av_sigmaI/netI    0.0519
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       20
_diffrn_reflns_limit_k_min       -20
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            13001
_diffrn_reflns_theta_full        27.52
_diffrn_reflns_theta_max         27.52
_diffrn_reflns_theta_min         2.11
_diffrn_standards_decay_%        none
_exptl_absorpt_coefficient_mu    0.075
_exptl_absorpt_correction_type   semi-empirical
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.176
_exptl_crystal_density_method    'not measured'
_exptl_crystal_F_000             712
_exptl_crystal_size_max          0.44
_exptl_crystal_size_mid          0.40
_exptl_crystal_size_min          0.11
_refine_diff_density_max         0.300
_refine_diff_density_min         -0.155
_refine_diff_density_rms         0.039
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.020
_refine_ls_hydrogen_treatment    riding
_refine_ls_matrix_type           full
_refine_ls_number_parameters     229
_refine_ls_number_reflns         4278
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.020
_refine_ls_R_factor_all          0.0788
_refine_ls_R_factor_gt           0.0524
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0714P)^2^+0.3076P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1400
_refine_ls_wR_factor_ref         0.1590
_reflns_number_gt                2899
_reflns_number_total             4278
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol801656y_si_002.cif
_cod_data_source_block           ms50ccd
_cod_original_sg_symbol_H-M      P21/c
_cod_database_code               1504877