Preparation of zwitterionic hydroquinone-fused [1,4]oxazinium derivatives via a photoinduced intramolecular dehydrogenative-coupling reaction.
Yi, Chenyi; Liu, Shi-Xia; Neels, Antonia; Renaud, Philippe; Decurtins, Silvio; Organic letters 11 (2009) 5530–5533; doi:10.1021/ol902355b

data_1504297
_publ_section_title
;
 Preparation of zwitterionic hydroquinone-fused [1,4]oxazinium derivatives
 via a photoinduced intramolecular dehydrogenative-coupling reaction.
;
_journal_issue                   23
_journal_name_full               'Organic letters'
_journal_page_first              5530
_journal_page_last               5533
_journal_paper_doi               10.1021/ol902355b
_journal_volume                  11
_journal_year                    2009
_chemical_formula_sum            'C16 H11 N3 O3'
_chemical_formula_weight         293.28
_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                 102.299(11)
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   21.754(3)
_cell_length_b                   8.5010(18)
_cell_length_c                   14.483(2)
_cell_measurement_reflns_used    3936
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      25.59
_cell_measurement_theta_min      1.92
_cell_volume                     2616.9(8)
_computing_cell_refinement       'STOE X-AREA'
_computing_data_collection       'STOE X-AREA'
_computing_data_reduction        'STOE X-RED'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      173(2)
_diffrn_detector_area_resol_mean 6.67
_diffrn_measured_fraction_theta_full 0.988
_diffrn_measured_fraction_theta_max 0.988
_diffrn_measurement_device_type  'STOE IPDS 2'
_diffrn_measurement_method       'rotation method'
_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  0.1212
_diffrn_reflns_av_sigmaI/netI    0.0873
_diffrn_reflns_limit_h_max       25
_diffrn_reflns_limit_h_min       -26
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            11268
_diffrn_reflns_theta_full        25.73
_diffrn_reflns_theta_max         25.73
_diffrn_reflns_theta_min         1.92
_exptl_absorpt_coefficient_mu    0.106
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            red
_exptl_crystal_density_diffrn    1.489
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             1216
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.30
_exptl_crystal_size_min          0.10
_refine_diff_density_max         1.283
_refine_diff_density_min         -0.367
_refine_diff_density_rms         0.104
_refine_ls_extinction_coef       0.0084(19)
_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   0.997
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     202
_refine_ls_number_reflns         2482
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      0.997
_refine_ls_R_factor_all          0.1408
_refine_ls_R_factor_gt           0.0882
_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^)+(0.1608P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2272
_refine_ls_wR_factor_ref         0.2586
_reflns_number_gt                1421
_reflns_number_total             2482
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol902355b_si_001.cif
_cod_data_source_block           y328
_cod_original_sg_symbol_H-M      'C 2/c'
_cod_database_code               1504297