<i>tert</i>-Butylhydroperoxide (TBHP) mediated oxidative cross-dehydrogenative coupling of quinoxalin-2(1<i>H</i>)-ones with 4-hydroxycoumarins, 4-hydroxy-6-methyl-2-pyrone and 2-hydroxy-1,4-naphthoquinone under metal-free conditions.
Sharma, Suraj; Dutta, Nibedita Baruah; Bhuyan, Mayurakhi; Das, Babulal; Baishya, Gakul; Organic & biomolecular chemistry 18 (2020) 6537–6548; doi:10.1039/d0ob01304h

data_7157644
_publ_section_title
;
 <i>tert</i>-Butylhydroperoxide (TBHP) mediated oxidative
 cross-dehydrogenative coupling of quinoxalin-2(1<i>H</i>)-ones with
 4-hydroxycoumarins, 4-hydroxy-6-methyl-2-pyrone and
 2-hydroxy-1,4-naphthoquinone under metal-free conditions.
;
_journal_issue                   33
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              6537
_journal_page_last               6548
_journal_paper_doi               10.1039/d0ob01304h
_journal_volume                  18
_journal_year                    2020
_chemical_formula_sum            'C21 H16 N2 O4'
_chemical_formula_weight         360.36
_space_group_crystal_system      orthorhombic
_space_group_IT_number           60
_space_group_name_Hall           '-P 2n 2ab'
_space_group_name_H-M_alt        'P b c n'
_atom_sites_solution_hydrogens   geom
_audit_creation_method           SHELXL-2014/7
_audit_update_record
;
2020-06-04 deposited with the CCDC.	2020-08-04 downloaded from the CCDC.
;
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_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_formula_units_Z            8
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_cell_length_c                   14.5573(13)
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_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      24.995
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_cell_volume                     3483.0(5)
_computing_cell_refinement       'Bruker SMART'
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_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXL-2014/7 (Sheldrick, 2014)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0962
_diffrn_reflns_av_unetI/netI     0.0185
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 1.000
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -20
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_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
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_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 1.000
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_diffrn_reflns_theta_max         24.995
_diffrn_reflns_theta_min         1.894
_exptl_absorpt_coefficient_mu    0.097
_exptl_absorpt_correction_type   none
_exptl_crystal_colour            yellow
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_exptl_crystal_description       plates
_exptl_crystal_F_000             1504
_exptl_crystal_size_max          0.34
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_refine_diff_density_min         -0.153
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_refine_ls_extinction_coef       0.0135(11)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2014/7 (Sheldrick 2014'
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_refine_ls_matrix_type           full
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_refine_ls_number_reflns         3074
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.180
_refine_ls_R_factor_all          0.0716
_refine_ls_R_factor_gt           0.0559
_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^)+(0.0657P)^2^+2.2232P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1459
_refine_ls_wR_factor_ref         0.1644
_reflns_Friedel_coverage         0.000
_reflns_number_gt                2524
_reflns_number_total             3074
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d0ob01304h2.cif
_cod_data_source_block           SS-199_0ma_a
_cod_depositor_comments          'Adding full bibliography for 7157644.cif.'
_cod_database_code               7157644
_shelx_shelxl_version_number     2014/7
_shelx_res_checksum              58257