A difluorocarbene-triggered annulation/ring expansion cascade via sequential single-atom-insertions: direct assembly of 2-fluoroquinazolinones from azo compounds
Tian, Yingxian; Xiong, Yiyan; Wei, Jingyu; Zhu, Gongming; Chang, Junbiao; Liu, Bingxian; Chemical Science  (2026) –; doi:10.1039/D6SC00897F

data_1576776
_publ_section_title
;
 A difluorocarbene-triggered annulation/ring expansion cascade <i>via</i>
 sequential single-atom-insertions: direct assembly of
 2-fluoroquinazolinones from azo compounds.
;
_journal_issue                   16
_journal_name_full               'Chemical science'
_journal_page_first              8136
_journal_page_last               8147
_journal_paper_doi               10.1039/d6sc00897f
_journal_volume                  17
_journal_year                    2026
_chemical_formula_moiety         '4(C14 H7 Br2 F N2 O)'
_chemical_formula_sum            'C56 H28 Br8 F4 N8 O4'
_chemical_formula_weight         1592.14
_space_group_crystal_system      triclinic
_space_group_IT_number           2
_space_group_name_Hall           '-P 1'
_space_group_name_H-M_alt        'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     iterative
_audit_creation_date             2023-10-12
_audit_creation_method
;
Olex2 1.2
(compiled 2018.05.29 svn.r3508 for OlexSys, GUI svn.r5506)
;
_audit_update_record
;
2023-11-10 deposited with the CCDC.	2026-02-17 downloaded from the CCDC.
;
_cell_angle_alpha                90.985(3)
_cell_angle_beta                 109.561(3)
_cell_angle_gamma                100.644(3)
_cell_formula_units_Z            2
_cell_length_a                   11.3057(3)
_cell_length_b                   15.3237(5)
_cell_length_c                   16.8638(5)
_cell_measurement_reflns_used    6389
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      71.2880
_cell_measurement_theta_min      3.8720
_cell_volume                     2695.72(15)
_computing_cell_refinement       'CrysAlisPro 1.171.42.90a (Rigaku OD, 2023)'
_computing_data_collection       'CrysAlisPro 1.171.42.90a (Rigaku OD, 2023)'
_computing_data_reduction        'CrysAlisPro 1.171.42.90a (Rigaku OD, 2023)'
_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    'olex2.solve (Bourhis et al., 2015)'
_diffrn_ambient_temperature      293(2)
_diffrn_detector                 'CCD plate'
_diffrn_detector_area_resol_mean 8.0521
_diffrn_detector_type            EosS2
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.978
_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    -70.00 -45.00   1.00    1.00    --  -35.37 124.00-139.00   25
  2  \w    -62.00 -35.00   1.00    1.00    --  -35.37 147.00  25.00   27
  3  \w     26.00  86.00   1.00    1.00    --   35.37-124.00 141.00   60
  4  \w     75.00 102.00   1.00    1.00    --   35.37-147.00 -23.00   27
  5  \w     86.00 112.00   1.00    1.53    --  106.81 147.00  25.00   26
  6  \w     73.00 103.00   1.00    1.53    --  106.81-124.00 141.00   30
  7  \w    110.00 156.00   1.00    1.53    --  106.81 124.00-139.00   46
  8  \w    102.00 128.00   1.00    1.53    --  106.81-147.00 -23.00   26
  9  \w   -107.00 -41.00   1.00    1.00    --  -35.37-178.00  90.00   66
 10  \w    -68.00 -43.00   1.00    1.00    --  -35.37-178.00   0.00   25
 11  \w   -105.00 -16.00   1.00    1.00    --  -35.37 -38.00-120.00   89
 12  \w   -105.00 -16.00   1.00    1.00    --  -35.37 -38.00 -30.00   89
 13  \w    -92.00 -39.00   1.00    1.00    --  -35.37-178.00  30.00   53
 14  \w    -23.00  15.00   1.00    1.00    --   35.37 -57.00  30.00   38
 15  \w     68.00 106.00   1.00    1.00    --   35.37 178.00  90.00   38
 16  \w      8.00  47.00   1.00    1.00    --   35.37 -57.00-120.00   39
 17  \w    -29.00   3.00   1.00    1.00    --   35.37 -57.00-120.00   32
 18  \w     38.00 122.00   1.00    1.53    --  106.81 -45.00-180.00   84
 19  \w    119.00 146.00   1.00    1.53    --  106.81 111.00 -60.00   27
 20  \w     39.00 126.00   1.00    1.53    --  106.81 -77.00-180.00   87
 21  \w     86.00 176.00   1.00    1.53    --  106.81  30.00 -90.00   90
 22  \w     37.00  93.00   1.00    1.53    --  106.81 -95.00 -30.00   56
 23  \w    117.00 144.00   1.00    1.53    --  106.81 178.00 -60.00   27
 24  \w     40.00 108.00   1.00    1.53    --  106.81-111.00 150.00   68
 25  \w     65.00  92.00   1.00    1.53    --  106.81 178.00 -60.00   27
 26  \w     40.00 126.00   1.00    1.53    --  106.81 -30.00  90.00   86
 27  \w     53.00 128.00   1.00    1.53    --  106.81 -30.00 -60.00   75
 28  \w    104.00 137.00   1.00    1.53    --  106.81 111.00 -90.00   33
 29  \w    145.00 170.00   1.00    1.53    --  106.81 111.00 -90.00   25
 30  \w     82.00 108.00   1.00    1.53    --  106.81-111.00  30.00   26
 31  \w     65.00 133.00   1.00    1.53    --  106.81 178.00 150.00   68
 32  \w     48.00  96.00   1.00    1.53    --  106.81 -61.00 -60.00   48
 33  \w     37.00 141.00   1.00    1.53    --  106.81 -15.00-120.00  104
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'SuperNova, Dual, Cu at home/near, EosS2'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_type
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      0.0440255000
_diffrn_orient_matrix_UB_12      0.0141428000
_diffrn_orient_matrix_UB_13      0.0970012000
_diffrn_orient_matrix_UB_21      -0.0449178000
_diffrn_orient_matrix_UB_22      -0.1004999000
_diffrn_orient_matrix_UB_23      0.0041751000
_diffrn_orient_matrix_UB_31      0.1335931000
_diffrn_orient_matrix_UB_32      -0.0155121000
_diffrn_orient_matrix_UB_33      0.0064282000
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0343
_diffrn_reflns_av_unetI/netI     0.0390
_diffrn_reflns_Laue_measured_fraction_full 0.998
_diffrn_reflns_Laue_measured_fraction_max 0.978
_diffrn_reflns_limit_h_max       13
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       18
_diffrn_reflns_limit_k_min       -18
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            20750
_diffrn_reflns_point_group_measured_fraction_full 0.998
_diffrn_reflns_point_group_measured_fraction_max 0.978
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         71.405
_diffrn_reflns_theta_min         3.882
_diffrn_source                   'micro-focus sealed X-ray tube'
_diffrn_source_type              'SuperNova (Cu) X-ray Source'
_exptl_absorpt_coefficient_mu    7.719
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.13105
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.42.90a (Rigaku Oxford Diffraction, 2023)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            'clear light colourless'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   light
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.961
_exptl_crystal_description       block
_exptl_crystal_F_000             1536
_exptl_crystal_size_max          0.1
_exptl_crystal_size_mid          0.1
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.961
_refine_diff_density_min         -0.955
_refine_diff_density_rms         0.107
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.027
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     721
_refine_ls_number_reflns         10255
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.027
_refine_ls_R_factor_all          0.0799
_refine_ls_R_factor_gt           0.0486
_refine_ls_shift/su_max          0.018
_refine_ls_shift/su_mean         0.005
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0875P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1535
_refine_ls_wR_factor_ref         0.1869
_reflns_Friedel_coverage         0.000
_reflns_number_gt                4537
_reflns_number_total             10255
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d6sc00897f2.cif
_cod_data_source_block           xyy-2-20231012_auto
_cod_depositor_comments          'Adding full bibliography for 1576776.cif.'
_cod_original_cell_volume        2695.71(15)
_cod_database_code               1576776
_shelx_shelxl_version_number     2018/3
_chemical_oxdiff_formula         'C1 H1 O1 N1 Br1'
_shelx_estimated_absorpt_t_max   0.512
_shelx_estimated_absorpt_t_min   0.512
_diffrn_oxdiff_digest_frames
;
01732d09a6fd5c5328def4dc18de729bcf000270aab
;
_diffrn_oxdiff_digest_hkl
;
0170572d7de11fcd36b3185121ee7a0bd4e889
;
_reflns_odcompleteness_completeness 99.88
_reflns_odcompleteness_iscentric 1
_reflns_odcompleteness_theta     66.97
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups
2.a Aromatic/amide H refined with riding coordinates:
 C36(H36), C45(H45), C27(H27), C5(H5), C24(H24), C64(H64), C12(H12), C3(H3),
 C56(H56), C52(H52), C32(H32), C55(H55), C26(H26), C76(H76), C15(H15), C66(H66),
  C75(H75), C73(H73), C72(H72), C43(H43), C42(H42), C35(H35), C33(H33),
 C13(H13), C53(H53), C2(H2), C67(H67), C16(H16)
;
_shelx_res_checksum              1892
_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 2.645
_oxdiff_exptl_absorpt_empirical_full_min 0.478