Unexpected Synthesis of 2,4,5-Trisubstituted Oxazoles via a Tandem Aza-Wittig/Michael/Isomerization Reaction of Vinyliminophosphorane
Hai Xie; Ding Yuan; Ming-Wu Ding; Journal of Organic Chemistry 77 (2012) 2954–2958; doi:10.1021/jo202588j

data_4027068
_publ_section_title
;
 Unexpected Synthesis of 2,4,5-Trisubstituted Oxazoles via a Tandem
 Aza-Wittig/Michael/Isomerization Reaction of Vinyliminophosphorane
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              2954
_journal_page_last               2958
_journal_paper_doi               10.1021/jo202588j
_journal_volume                  77
_journal_year                    2012
_chemical_formula_moiety         'C17 H15 N O2'
_chemical_formula_sum            'C17 H15 N O2'
_chemical_formula_weight         265.30
_space_group_IT_number           15
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-C 2yc'
_symmetry_space_group_name_H-M   'C 1 2/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                 116.514(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   19.856(4)
_cell_length_b                   7.3460(13)
_cell_length_c                   20.945(4)
_cell_measurement_reflns_used    6740
_cell_measurement_temperature    298(2)
_cell_measurement_theta_max      27.90
_cell_measurement_theta_min      2.17
_cell_volume                     2733.8(9)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      298(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_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  0.0252
_diffrn_reflns_av_sigmaI/netI    0.0216
_diffrn_reflns_limit_h_max       26
_diffrn_reflns_limit_h_min       -26
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       27
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            16162
_diffrn_reflns_theta_full        28.35
_diffrn_reflns_theta_max         28.35
_diffrn_reflns_theta_min         2.17
_exptl_absorpt_coefficient_mu    0.085
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.289
_exptl_crystal_description       block
_exptl_crystal_F_000             1120
_exptl_crystal_size_max          0.20
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.224
_refine_diff_density_min         -0.193
_refine_diff_density_rms         0.052
_refine_ls_extinction_coef       0.0047(8)
_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   1.050
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     187
_refine_ls_number_reflns         3404
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.051
_refine_ls_R_factor_all          0.0548
_refine_ls_R_factor_gt           0.0479
_refine_ls_shift/su_max          0.004
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0841P)^2^+0.6395P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1358
_refine_ls_wR_factor_ref         0.1429
_reflns_number_gt                2849
_reflns_number_total             3404
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo202588j_si_001.cif
_cod_data_source_block           110426lm
_cod_original_cell_volume        2733.8(8)
_cod_database_code               4027068