Chemoselective intramolecular Wittig reactions for the synthesis of oxazoles and benzofurans.
Fan, Yu-Shiou; Das, Utpal; Hsiao, Ming-Yu; Liu, Meng-Hsien; Lin, Wenwei; The Journal of organic chemistry 79 (2014) 11567–11582; doi:10.1021/jo502232q

data_4030625
_publ_section_title
;
 Chemoselective intramolecular Wittig reactions for the synthesis of
 oxazoles and benzofurans.
;
_journal_issue                   23
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              11567
_journal_page_last               11582
_journal_paper_doi               10.1021/jo502232q
_journal_volume                  79
_journal_year                    2014
_chemical_formula_moiety         'C28 H17 Br2 N O3'
_chemical_formula_sum            'C28 H17 Br2 N O3'
_chemical_formula_weight         575.25
_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                 93.811(11)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   18.879(3)
_cell_length_b                   13.056(2)
_cell_length_c                   9.5076(16)
_cell_measurement_reflns_used    0
_cell_measurement_temperature    200(2)
_cell_measurement_theta_max      0
_cell_measurement_theta_min      0
_cell_volume                     2338.3(6)
_computing_molecular_graphics    'Ortep-3 for Windows (Farrugia, 1997)'
_computing_publication_material  'WinGX publication routines (Farrugia, 1999)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-86 (Sheldrick, 1986)'
_diffrn_ambient_temperature      200(2)
_diffrn_measured_fraction_theta_full 0.988
_diffrn_measured_fraction_theta_max 0.988
_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  0.0945
_diffrn_reflns_av_sigmaI/netI    0.1415
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -22
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            15226
_diffrn_reflns_theta_full        25.06
_diffrn_reflns_theta_max         25.06
_diffrn_reflns_theta_min         1.08
_exptl_absorpt_coefficient_mu    3.498
_exptl_absorpt_correction_T_max  0.8727
_exptl_absorpt_correction_T_min  0.4200
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.634
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             1144
_exptl_crystal_size_max          0.30
_exptl_crystal_size_mid          0.09
_exptl_crystal_size_min          0.04
_refine_diff_density_max         1.374
_refine_diff_density_min         -0.582
_refine_diff_density_rms         0.137
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.002
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     307
_refine_ls_number_reflns         4109
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.002
_refine_ls_R_factor_all          0.1706
_refine_ls_R_factor_gt           0.0676
_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^)+(0.1094P)^2^+0.3415P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1589
_refine_ls_wR_factor_ref         0.2240
_reflns_number_gt                1952
_reflns_number_total             4109
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo502232q_si_002.cif
_cod_data_source_block           13748
_cod_original_cell_volume        2338.2(7)
_cod_original_sg_symbol_H-M      'P 21/c'
_cod_database_code               4030625