Base-Mediated Cascade Substitution-Cyclization of 2H-Azirines: Access to Highly Substituted Oxazoles.
Duan, Xiyan; Yang, Kun; Lu, Jun; Kong, Xianglei; Liu, Ning; Ma, Junying; Organic letters 19 (2017) 3370–3373; doi:10.1021/acs.orglett.7b01305

data_1546307
_publ_section_title
;
 Base-Mediated Cascade Substitution-Cyclization of 2H-Azirines: Access to
 Highly Substituted Oxazoles.
;
_journal_issue                   13
_journal_name_full               'Organic letters'
_journal_page_first              3370
_journal_page_last               3373
_journal_paper_doi               10.1021/acs.orglett.7b01305
_journal_volume                  19
_journal_year                    2017
_chemical_formula_moiety         'C18 H13 N3 O'
_chemical_formula_sum            'C18 H13 N3 O'
_chemical_formula_weight         287.31
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_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     dual
_audit_creation_date             2017-03-24
_audit_creation_method
;
Olex2 1.2-beta
(compiled 2016.09.09 svn.r3337 for OlexSys, GUI svn.r5227)
;
_cell_angle_alpha                90
_cell_angle_beta                 93.816(9)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   5.332(3)
_cell_length_b                   19.341(9)
_cell_length_c                   14.278(7)
_cell_measurement_reflns_used    2254
_cell_measurement_temperature    296.15
_cell_measurement_theta_max      23.978
_cell_measurement_theta_min      2.546
_cell_volume                     1469.2(13)
_computing_cell_refinement       'SAINT v8.34A (Bruker, 2013)'
_computing_data_reduction        'SAINT v8.34A (Bruker, 2013)'
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'ShelXL (Sheldrick, 2015)'
_computing_structure_solution    'ShelXT (Sheldrick, 2015)'
_diffrn_ambient_temperature      296.15
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Bruker P4'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0305
_diffrn_reflns_av_unetI/netI     0.0340
_diffrn_reflns_Laue_measured_fraction_full 0.998
_diffrn_reflns_Laue_measured_fraction_max 0.998
_diffrn_reflns_limit_h_max       6
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       24
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       16
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            9118
_diffrn_reflns_point_group_measured_fraction_full 0.998
_diffrn_reflns_point_group_measured_fraction_max 0.998
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         26.370
_diffrn_reflns_theta_min         1.775
_exptl_absorpt_coefficient_mu    0.083
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.6905
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2014/5 (Bruker,2014/5) was used for absorption correction.
wR2(int) was 0.0908 before and 0.0457 after correction.
The Ratio of minimum to maximum transmission is 0.9261.
The \l/2 correction factor is 0.00150.
;
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.299
_exptl_crystal_description       block
_exptl_crystal_F_000             600
_refine_diff_density_max         0.131
_refine_diff_density_min         -0.220
_refine_diff_density_rms         0.035
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.039
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     199
_refine_ls_number_reflns         3001
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.039
_refine_ls_R_factor_all          0.0691
_refine_ls_R_factor_gt           0.0422
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0471P)^2^+0.1737P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0986
_refine_ls_wR_factor_ref         0.1128
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2039
_reflns_number_total             3001
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ol7b01305_si_002.cif
_cod_data_source_block           20170321_xl_ycx_0m
_cod_depositor_comments          'Adding full bibliography for 1546307.cif.'
_cod_database_code               1546307
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups
2.a Aromatic/amide H refined with riding coordinates:
 C3(H3), C4(H4), C5(H5), C8(H8), C9(H9), C10(H10), C11(H11), C12(H12),
 C14(H14), C15(H15), C16(H16), C17(H17), C18(H18)
;
_shelx_res_checksum              55246
_shelx_hkl_checksum              4836
_shelx_shelxl_version_number     2014/7
_olex2_submission_special_instructions 'No special instructions were received'