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_4030635
_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         'C26 H16 Br N O4'
_chemical_formula_sum            'C26 H16 Br N O4'
_chemical_formula_weight         486.31
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2yn'
_symmetry_space_group_name_H-M   'P 1 21/n 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                 91.025(6)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   8.4380(13)
_cell_length_b                   18.194(2)
_cell_length_c                   14.098(2)
_cell_measurement_reflns_used    0
_cell_measurement_temperature    200(2)
_cell_measurement_theta_max      0
_cell_measurement_theta_min      0
_cell_volume                     2164.0(5)
_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 0.990
_diffrn_measured_fraction_theta_max 0.990
_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  0.0706
_diffrn_reflns_av_sigmaI/netI    0.1346
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       21
_diffrn_reflns_limit_k_min       -17
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -16
_diffrn_reflns_number            8602
_diffrn_reflns_theta_full        25.01
_diffrn_reflns_theta_max         25.01
_diffrn_reflns_theta_min         2.24
_exptl_absorpt_coefficient_mu    1.933
_exptl_absorpt_correction_T_max  0.8928
_exptl_absorpt_correction_T_min  0.5510
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            'pale yellow'
_exptl_crystal_density_diffrn    1.493
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             984
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.28
_exptl_crystal_size_min          0.06
_refine_diff_density_max         0.662
_refine_diff_density_min         -0.531
_refine_diff_density_rms         0.090
_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     283
_refine_ls_number_reflns         3771
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.002
_refine_ls_R_factor_all          0.1406
_refine_ls_R_factor_gt           0.0597
_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^)+(0.0426P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1028
_refine_ls_wR_factor_ref         0.1247
_reflns_number_gt                2005
_reflns_number_total             3771
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo502232q_si_002.cif
_cod_data_source_block           a15595a
_cod_original_sg_symbol_H-M      'P 21/n'
_cod_database_code               4030635