Metal-free regioselective nitration of quinoxalin-2(1<i>H</i>)-ones with <i>tert</i>-butyl nitrite.
Li, Yi-Na; Li, Xue-Lin; Wu, Jin-Bo; Jiang, Hong; Liu, Yunmei; Guo, Yu; Zeng, Yao-Fu; Wang, Zhen; Organic & biomolecular chemistry 19 (2021) 10554–10559; doi:10.1039/d1ob02015c

data_7158431
_publ_section_title
;
 Metal-free regioselective nitration of quinoxalin-2(1<i>H</i>)-ones with
 <i>tert</i>-butyl nitrite.
;
_journal_issue                   48
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              10554
_journal_page_last               10559
_journal_paper_doi               10.1039/d1ob02015c
_journal_volume                  19
_journal_year                    2021
_chemical_formula_moiety         'C17 H14 Br N3 O3'
_chemical_formula_sum            'C17 H14 Br N3 O3'
_chemical_formula_weight         388.22
_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'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_audit_creation_date             2021-11-08
_audit_creation_method
;
Olex2 1.3
(compiled 2020.11.12 svn.r5f609507 for OlexSys, GUI svn.r6408)
;
_audit_update_record
;
2021-11-08 deposited with the CCDC.	2021-12-02 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 102.210(9)
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   21.4559(18)
_cell_length_b                   8.8913(8)
_cell_length_c                   17.8312(16)
_cell_measurement_reflns_used    3092
_cell_measurement_temperature    292.99(10)
_cell_measurement_theta_max      22.9070
_cell_measurement_theta_min      2.3160
_cell_volume                     3324.7(5)
_computing_cell_refinement       'CrysAlisPro 1.171.38.43f (Rigaku OD, 2015)'
_computing_data_collection       'CrysAlisPro 1.171.38.43f (Rigaku OD, 2015)'
_computing_data_reduction        'CrysAlisPro 1.171.38.43f (Rigaku OD, 2015)'
_computing_molecular_graphics    'Olex2 1.3 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.3 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2018/3 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT 2018/2 (Sheldrick, 2018)'
_diffrn_ambient_environment      air
_diffrn_ambient_temperature      292.99(10)
_diffrn_detector                 'CCD plate'
_diffrn_detector_area_resol_mean 5.2684
_diffrn_detector_type            AtlasS2
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_details
;
List of Runs (angles in degrees, time in seconds):

  # Type    Start    End  Width  t~exp~   \w     \q     \k     \f   Frames
  1  \w    -64.00  44.00   1.00    7.00    --   11.90 -77.00 -30.00  108
  2  \w    -15.00  12.00   1.00    7.00    --  -11.35 -99.00-120.00   27
  3  \w     36.00  84.00   1.00    7.00    --   11.90-178.00 -30.00   48
  4  \w    -74.00 -18.00   1.00    7.00    --  -11.35 -77.00 150.00   56
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'SuperNova, Dual, Cu at zero, AtlasS2'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_type
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      0.0042596000
_diffrn_orient_matrix_UB_12      0.0469510000
_diffrn_orient_matrix_UB_13      0.0328529000
_diffrn_orient_matrix_UB_21      0.0328315000
_diffrn_orient_matrix_UB_22      0.0072865000
_diffrn_orient_matrix_UB_23      -0.0004281000
_diffrn_orient_matrix_UB_31      -0.0068496000
_diffrn_orient_matrix_UB_32      0.0640880000
_diffrn_orient_matrix_UB_33      -0.0240306000
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0614
_diffrn_reflns_av_unetI/netI     0.0952
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       23
_diffrn_reflns_limit_h_min       -25
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            17453
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_theta_full        25.000
_diffrn_reflns_theta_max         25.000
_diffrn_reflns_theta_min         2.334
_diffrn_source                   'micro-focus sealed X-ray tube'
_diffrn_source_type              'SuperNova (Mo) X-ray Source'
_exptl_absorpt_coefficient_mu    2.493
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.39194
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.38.43f (Rigaku Oxford Diffraction, 2015)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colourless
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.551
_exptl_crystal_description       block
_exptl_crystal_F_000             1568
_exptl_crystal_size_max          0.14
_exptl_crystal_size_mid          0.12
_exptl_crystal_size_min          0.11
_refine_diff_density_max         0.495
_refine_diff_density_min         -0.416
_refine_diff_density_rms         0.062
_refine_ls_extinction_coef       0.00144(17)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2018/3 (Sheldrick 2018)'
_refine_ls_goodness_of_fit_ref   1.018
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     438
_refine_ls_number_reflns         5861
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.018
_refine_ls_R_factor_all          0.1298
_refine_ls_R_factor_gt           0.0554
_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^)+(0.0335P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0981
_refine_ls_wR_factor_ref         0.1249
_reflns_Friedel_coverage         0.000
_reflns_number_gt                3141
_reflns_number_total             5861
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d1ob02015c2.cif
_cod_data_source_block           lyn-g
_cod_depositor_comments          'Adding full bibliography for 7158431.cif.'
_cod_database_code               7158431
_shelx_shelxl_version_number     2018/3
_reflns_odcompleteness_completeness 99.90
_reflns_odcompleteness_iscentric 1
_reflns_odcompleteness_theta     26.32
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2.a Secondary CH2 refined with riding coordinates:
 C7(H7A,H7B), C24(H24A,H24B)
2.b Aromatic/amide H refined with riding coordinates:
 C2(H2), C3(H3), C5(H5), C6(H6), C9(H9), C14(H14), C19(H19), C20(H20),
 C22(H22), C23(H23), C26(H26), C29(H29)
2.c Idealised Me refined as rotating group:
 C16(H16A,H16B,H16C), C17(H17A,H17B,H17C), C33(H33A,H33B,H33C), C34(H34A,H34B,
 H34C)
;
_shelx_res_checksum              16896
_olex2_submission_special_instructions 'No special instructions were received'
_oxdiff_exptl_absorpt_empirical_details
;
Empirical correction (ABSPACK) includes:
- Absorption correction using spherical harmonics
- Frame scaling
;
_oxdiff_exptl_absorpt_empirical_full_max 1.940
_oxdiff_exptl_absorpt_empirical_full_min 0.542