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_4030627
_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           61
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_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            8
_cell_length_a                   15.7067(19)
_cell_length_b                   16.039(2)
_cell_length_c                   17.011(2)
_cell_measurement_reflns_used    0
_cell_measurement_temperature    200(2)
_cell_measurement_theta_max      0
_cell_measurement_theta_min      0
_cell_volume                     4285.4(9)
_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 0.993
_diffrn_measured_fraction_theta_max 0.993
_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  0.0514
_diffrn_reflns_av_sigmaI/netI    0.0522
_diffrn_reflns_limit_h_max       16
_diffrn_reflns_limit_h_min       -18
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            17023
_diffrn_reflns_theta_full        25.02
_diffrn_reflns_theta_max         25.02
_diffrn_reflns_theta_min         2.39
_exptl_absorpt_coefficient_mu    1.952
_exptl_absorpt_correction_T_max  0.8439
_exptl_absorpt_correction_T_min  0.4944
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            'pale gray'
_exptl_crystal_density_diffrn    1.507
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             1968
_exptl_crystal_size_max          0.42
_exptl_crystal_size_mid          0.28
_exptl_crystal_size_min          0.09
_refine_diff_density_max         0.375
_refine_diff_density_min         -0.553
_refine_diff_density_rms         0.057
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.001
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     289
_refine_ls_number_reflns         3763
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.001
_refine_ls_R_factor_all          0.0788
_refine_ls_R_factor_gt           0.0408
_refine_ls_shift/su_max          0.003
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0399P)^2^+1.9191P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0812
_refine_ls_wR_factor_ref         0.0945
_reflns_number_gt                2552
_reflns_number_total             3763
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo502232q_si_002.cif
_cod_data_source_block           ch15582a
_cod_database_code               4030627