# Supplementary Information (SI) for Organic Chemistry Frontiers.
# This journal is © the Partner Organisations 2026

####################################################################### 
# 
# This file contains crystal structure data downloaded from the 
# Cambridge Structural Database (CSD) hosted by the Cambridge 
# Crystallographic Data Centre (CCDC).
# 
# Full information about CCDC data access policies and citation 
# guidelines are available at http://www.ccdc.cam.ac.uk/access/V1 
# 
# Audit and citation data items may have been added by the CCDC. 
# Please retain this information to preserve the provenance of 
# this file and to allow appropriate attribution of the data. 
# 
#######################################################################

data_ska-172-s2-4br_auto
_database_code_depnum_ccdc_archive 'CCDC 2493474'
loop_
_audit_author_name
_audit_author_address
'Vikas Tyagi'
;Thapar Institute of Engineering and Technology
India
;
_audit_update_record             
;
2025-10-06 deposited with the CCDC.	2026-06-05 downloaded from the CCDC.
;
_audit_creation_date             2025-08-01
_audit_creation_method           
;
Olex2 1.5
(compiled 2025.07.13 svn.rb7424aed for OlexSys, GUI svn.r7311)
;
_shelx_SHELXL_version_number     2019/2
_chemical_name_common            ?
_chemical_name_systematic        ?
_chemical_formula_moiety         'C18 H14 Br2 O4'
_chemical_formula_sum            'C18 H14 Br2 O4'
_chemical_formula_weight         454.11
_chemical_melting_point          ?
_chemical_oxdiff_formula         'C H O Br'
_chemical_oxdiff_usercomment     'colourless block'
loop_
_atom_type_symbol
_atom_type_description
_atom_type_scat_dispersion_real
_atom_type_scat_dispersion_imag
_atom_type_scat_source
C C 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
Br Br -0.2901 2.4595 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
O O 0.0106 0.0060 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'

_shelx_space_group_comment       
;
The symmetry employed for this shelxl refinement is uniquely defined
by the following loop, which should always be used as a source of
symmetry information in preference to the above space-group names.
They are only intended as comments.
;
_space_group_crystal_system      triclinic
_space_group_IT_number           2
_space_group_name_H-M_alt        'P -1'
_space_group_name_Hall           '-P 1'
loop_
_space_group_symop_operation_xyz
'x, y, z'
'-x, -y, -z'

_cell_length_a                   11.5931(4)
_cell_length_b                   11.8651(4)
_cell_length_c                   13.9114(4)
_cell_angle_alpha                73.921(3)
_cell_angle_beta                 82.098(3)
_cell_angle_gamma                72.791(3)
_cell_volume                     1753.17(11)
_cell_formula_units_Z            4
_cell_measurement_reflns_used    12998
_cell_measurement_temperature    100.01(10)
_cell_measurement_theta_max      30.5460
_cell_measurement_theta_min      3.6510
_shelx_estimated_absorpt_T_max   0.524
_shelx_estimated_absorpt_T_min   0.428
_exptl_absorpt_coefficient_mu    4.642
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.37635
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   
;
CrysAlisPro 1.171.42.89a (Rigaku Oxford Diffraction, 2023)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_absorpt_special_details   ?
_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    1.720
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    ?
_exptl_crystal_description       block
_exptl_crystal_F_000             896
_exptl_crystal_preparation       'As per the reaction scheme'
_exptl_crystal_recrystallization_method 'Slow evaporation method'
_exptl_crystal_size_max          0.22
_exptl_crystal_size_mid          0.18
_exptl_crystal_size_min          0.16
_exptl_transmission_factor_max   ?
_exptl_transmission_factor_min   ?
_diffrn_reflns_av_R_equivalents  0.0554
_diffrn_reflns_av_unetI/netI     0.0588
_diffrn_reflns_Laue_measured_fraction_full 0.997
_diffrn_reflns_Laue_measured_fraction_max 0.793
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -14
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       18
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            32420
_diffrn_reflns_point_group_measured_fraction_full 0.997
_diffrn_reflns_point_group_measured_fraction_max 0.793
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         30.812
_diffrn_reflns_theta_min         3.287
_diffrn_ambient_environment      N~2~
_diffrn_ambient_temperature      100.01(10)
_diffrn_detector                 'Hybrid Pixel Array Detector'
_diffrn_detector_area_resol_mean 5.8140
_diffrn_detector_type            'Pilatus 200K'
_diffrn_measured_fraction_theta_full 0.9969
_diffrn_measured_fraction_theta_max 0.7933
_diffrn_measurement_details      
;
List of Runs (angles in degrees, time in seconds):

  # Type    Start    End  Width  tₑₓₚ   ω     θ     κ     φ   Frames
#--------------------------------------------------------------------------
  1  ω    -74.00  12.00   0.50    4.18    --   -5.17  -8.00 166.00  172
  2  ω    -22.00  64.00   0.50    4.18    --   -5.17   8.00 -18.00  172
  3  ω    -65.00  21.00   0.50    4.18    --    4.07  -8.00 166.00  172
  4  ω    -42.00  18.00   0.50    4.18    --   -5.17 -77.00 120.00  120
  5  ω    -42.00  18.00   0.50    4.18    --   -5.17 -77.00   0.00  120
  6  ω    -42.00  18.00   0.50    4.18    --   -5.17 -77.00 -60.00  120
  7  ω    -28.00  21.00   0.50    4.18    --   -5.17  77.00-150.00   98
  8  ω    -15.00  10.00   0.50    4.18    --    4.07 -99.00  60.00   50
  9  ω    -65.00  10.00   0.50    4.18    --    4.07 -19.00 120.00  150
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  
'SuperNova, Dual, Cu at home/near, Pilatus 200K'
_diffrn_measurement_method       'ω scans'
_diffrn_orient_matrix_type       
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      0.0117844000
_diffrn_orient_matrix_UB_12      0.0558813000
_diffrn_orient_matrix_UB_13      -0.0016511000
_diffrn_orient_matrix_UB_21      0.0629935000
_diffrn_orient_matrix_UB_22      -0.0273887000
_diffrn_orient_matrix_UB_23      -0.0056821000
_diffrn_orient_matrix_UB_31      -0.0032360000
_diffrn_orient_matrix_UB_32      0.0174409000
_diffrn_orient_matrix_UB_33      -0.0528300000
_diffrn_oxdiff_digest_frames     
;
016bdbadb2ee3b4ed06de99c6aaebff1c600025db35
;
_diffrn_oxdiff_digest_hkl        
;
01a9567c0b3e6830a895f276ab878f517bea53
;
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_source                   'micro-focus sealed X-ray tube'
_diffrn_source_type              'SuperNova (Mo) X-ray Source'
_reflns_Friedel_coverage         0.000
_reflns_Friedel_fraction_full    .
_reflns_Friedel_fraction_max     .
_reflns_number_gt                6681
_reflns_number_total             8721
_reflns_special_details          
;
 Reflections were merged by SHELXL according to the crystal
 class for the calculation of statistics and refinement.
 
 _reflns_Friedel_fraction is defined as the number of unique
 Friedel pairs measured divided by the number that would be
 possible theoretically, ignoring centric projections and
 systematic absences.
;
_reflns_threshold_expression     'I > 2σ(I)'
_computing_cell_refinement       'CrysAlisPro 1.171.42.89a (Rigaku OD, 2023)'
_computing_data_collection       'CrysAlisPro 1.171.42.89a (Rigaku OD, 2023)'
_computing_data_reduction        'CrysAlisPro 1.171.42.89a (Rigaku OD, 2023)'
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2019/2 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT 2014/5 (Sheldrick, 2014)'
_refine_diff_density_max         0.788
_refine_diff_density_min         -0.589
_refine_diff_density_rms         0.105
_refine_ls_extinction_coef       .
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.021
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     437
_refine_ls_number_reflns         8721
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0619
_refine_ls_R_factor_gt           0.0388
_refine_ls_restrained_S_all      1.021
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details     
'w=1/[σ²(Fo²)+(0.0373P)²] where P=(Fo²+2Fc²)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0743
_refine_ls_wR_factor_ref         0.0795
_refine_special_details          ?
_olex2_refinement_description    
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2.a Aromatic/amide H refined with riding coordinates:
 C8(H8), C9(H9), C11(H11), C12(H12), C14(H14), C15(H15), C17(H17), C18(H18),
 C26(H26), C27(H27), C29(H29), C30(H30), C32(H32), C33(H33), C35(H35), C36(H36)
2.b Idealised Me refined as rotating group:
 C1(H1A,H1B,H1C), C6(H6A,H6B,H6C), C19(H19A,H19B,H19C), C24(H24A,H24B,H24C)
;
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_atom_sites_solution_secondary   ?
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
_atom_site_adp_type
_atom_site_occupancy
_atom_site_site_symmetry_order
_atom_site_calc_flag
_atom_site_refinement_flags_posn
_atom_site_refinement_flags_adp
_atom_site_refinement_flags_occupancy
_atom_site_disorder_assembly
_atom_site_disorder_group
Br1 Br -0.08908(2) 0.07776(3) 0.60398(2) 0.02145(8) Uani 1 1 d . . . . .
Br2 Br 0.33861(3) -0.11744(3) 0.15432(2) 0.02451(8) Uani 1 1 d . . . . .
O1 O 0.65163(16) 0.18373(17) 0.37290(13) 0.0174(4) Uani 1 1 d . . . . .
O2 O 0.53824(17) 0.35934(18) 0.28119(14) 0.0197(4) Uani 1 1 d . . . . .
O3 O 0.52028(16) 0.33171(17) 0.50259(13) 0.0153(4) Uani 1 1 d . . . . .
O4 O 0.34944(17) 0.33575(17) 0.60167(13) 0.0167(4) Uani 1 1 d . . . . .
C1 C 0.7574(2) 0.2293(3) 0.3422(2) 0.0227(6) Uani 1 1 d . . . . .
H1A H 0.752673 0.293389 0.375626 0.034 Uiso 1 1 calc R U . . .
H1B H 0.760745 0.262873 0.269420 0.034 Uiso 1 1 calc R U . . .
H1C H 0.830426 0.162603 0.360838 0.034 Uiso 1 1 calc R U . . .
C2 C 0.5474(2) 0.2630(2) 0.34186(19) 0.0141(5) Uani 1 1 d . . . . .
C3 C 0.4407(2) 0.2134(2) 0.38605(18) 0.0114(5) Uani 1 1 d . . . . .
C4 C 0.3771(2) 0.2397(2) 0.46918(18) 0.0124(5) Uani 1 1 d . . . . .
C5 C 0.4242(2) 0.3070(2) 0.52493(18) 0.0127(5) Uani 1 1 d . . . . .
C6 C 0.3906(3) 0.4026(3) 0.6570(2) 0.0215(6) Uani 1 1 d . . . . .
H6A H 0.326110 0.430016 0.705517 0.032 Uiso 1 1 calc R U . . .
H6B H 0.411308 0.473393 0.610211 0.032 Uiso 1 1 calc R U . . .
H6C H 0.462163 0.349369 0.692432 0.032 Uiso 1 1 calc R U . . .
C7 C 0.4141(2) 0.1348(2) 0.33009(18) 0.0121(5) Uani 1 1 d . . . . .
C8 C 0.4042(2) 0.1733(2) 0.22694(19) 0.0147(5) Uani 1 1 d . . . . .
H8 H 0.413987 0.251224 0.191833 0.018 Uiso 1 1 calc R U . . .
C9 C 0.3800(2) 0.0995(2) 0.17427(19) 0.0163(6) Uani 1 1 d . . . . .
H9 H 0.371077 0.127277 0.104070 0.020 Uiso 1 1 calc R U . . .
C10 C 0.3693(2) -0.0151(2) 0.22591(19) 0.0150(5) Uani 1 1 d . . . . .
C11 C 0.3795(2) -0.0567(2) 0.32849(19) 0.0140(5) Uani 1 1 d . . . . .
H11 H 0.371698 -0.135519 0.362928 0.017 Uiso 1 1 calc R U . . .
C12 C 0.4013(2) 0.0192(2) 0.38017(19) 0.0128(5) Uani 1 1 d . . . . .
H12 H 0.407576 -0.008060 0.450695 0.015 Uiso 1 1 calc R U . . .
C13 C 0.2622(2) 0.2059(2) 0.50520(18) 0.0127(5) Uani 1 1 d . . . . .
C14 C 0.1695(2) 0.2413(2) 0.43979(19) 0.0124(5) Uani 1 1 d . . . . .
H14 H 0.178619 0.291728 0.374558 0.015 Uiso 1 1 calc R U . . .
C15 C 0.0647(2) 0.2043(2) 0.46830(19) 0.0151(5) Uani 1 1 d . . . . .
H15 H 0.002253 0.228305 0.423227 0.018 Uiso 1 1 calc R U . . .
C16 C 0.0527(2) 0.1316(2) 0.56396(19) 0.0142(5) Uani 1 1 d . . . . .
C17 C 0.1418(2) 0.0974(2) 0.63108(19) 0.0151(5) Uani 1 1 d . . . . .
H17 H 0.131587 0.048484 0.696746 0.018 Uiso 1 1 calc R U . . .
C18 C 0.2459(2) 0.1352(2) 0.60149(19) 0.0155(5) Uani 1 1 d . . . . .
H18 H 0.307114 0.112560 0.647486 0.019 Uiso 1 1 calc R U . . .
Br3 Br 0.28613(3) 0.59994(3) 0.41634(2) 0.02156(8) Uani 1 1 d . . . . .
Br4 Br -0.23793(3) 1.16506(3) 0.08307(2) 0.03208(9) Uani 1 1 d . . . . .
O5 O 0.02556(16) 0.31299(16) 0.20114(13) 0.0162(4) Uani 1 1 d . . . . .
O6 O -0.08155(18) 0.39192(17) 0.06377(14) 0.0217(4) Uani 1 1 d . . . . .
O7 O -0.25235(17) 0.64970(16) -0.03018(13) 0.0161(4) Uani 1 1 d . . . . .
O8 O -0.31421(17) 0.53877(19) 0.11578(13) 0.0204(4) Uani 1 1 d . . . . .
C19 C 0.0598(3) 0.1958(2) 0.1774(2) 0.0204(6) Uani 1 1 d . . . . .
H19A H 0.105285 0.201672 0.112243 0.031 Uiso 1 1 calc R U . . .
H19B H -0.013032 0.171190 0.174829 0.031 Uiso 1 1 calc R U . . .
H19C H 0.110483 0.135099 0.229184 0.031 Uiso 1 1 calc R U . . .
C20 C -0.0427(2) 0.4044(2) 0.13526(19) 0.0136(5) Uani 1 1 d . . . . .
C21 C -0.0619(2) 0.5246(2) 0.15957(18) 0.0129(5) Uani 1 1 d . . . . .
C22 C -0.1522(2) 0.6189(2) 0.11823(18) 0.0114(5) Uani 1 1 d . . . . .
C23 C -0.2417(2) 0.6026(2) 0.05794(19) 0.0130(5) Uani 1 1 d . . . . .
C24 C -0.4022(3) 0.5189(3) 0.0622(2) 0.0311(8) Uani 1 1 d . . . . .
H24A H -0.360279 0.478101 0.009784 0.047 Uiso 1 1 calc R U . . .
H24B H -0.457273 0.597407 0.031495 0.047 Uiso 1 1 calc R U . . .
H24C H -0.448603 0.467680 0.109014 0.047 Uiso 1 1 calc R U . . .
C25 C 0.0240(2) 0.5342(2) 0.22559(19) 0.0127(5) Uani 1 1 d . . . . .
C26 C 0.1466(2) 0.5105(2) 0.19878(19) 0.0162(6) Uani 1 1 d . . . . .
H26 H 0.177145 0.481813 0.140432 0.019 Uiso 1 1 calc R U . . .
C27 C 0.2257(2) 0.5282(2) 0.25660(19) 0.0168(6) Uani 1 1 d . . . . .
H27 H 0.309822 0.512678 0.238036 0.020 Uiso 1 1 calc R U . . .
C28 C 0.1789(2) 0.5689(2) 0.34156(19) 0.0142(5) Uani 1 1 d . . . . .
C29 C 0.0579(2) 0.5881(2) 0.37181(19) 0.0163(6) Uani 1 1 d . . . . .
H29 H 0.028550 0.612138 0.432303 0.020 Uiso 1 1 calc R U . . .
C30 C -0.0203(2) 0.5720(2) 0.31345(19) 0.0145(5) Uani 1 1 d . . . . .
H30 H -0.104163 0.586685 0.333020 0.017 Uiso 1 1 calc R U . . .
C31 C -0.1712(2) 0.7479(2) 0.11890(18) 0.0132(5) Uani 1 1 d . . . . .
C32 C -0.0740(2) 0.7991(3) 0.10506(18) 0.0163(6) Uani 1 1 d . . . . .
H32 H 0.006394 0.748793 0.101299 0.020 Uiso 1 1 calc R U . . .
C33 C -0.0937(3) 0.9219(3) 0.09680(19) 0.0182(6) Uani 1 1 d . . . . .
H33 H -0.027233 0.955997 0.088090 0.022 Uiso 1 1 calc R U . . .
C34 C -0.2114(3) 0.9951(2) 0.10135(19) 0.0180(6) Uani 1 1 d . . . . .
C35 C -0.3087(3) 0.9465(3) 0.1165(2) 0.0204(6) Uani 1 1 d . . . . .
H35 H -0.388899 0.996948 0.121329 0.025 Uiso 1 1 calc R U . . .
C36 C -0.2880(2) 0.8236(2) 0.12444(19) 0.0168(6) Uani 1 1 d . . . . .
H36 H -0.354906 0.790032 0.133906 0.020 Uiso 1 1 calc R U . . .


_geom_special_details            
;
 All esds (except the esd in the dihedral angle between two l.s. planes)
 are estimated using the full covariance matrix.  The cell esds are taken
 into account individually in the estimation of esds in distances, angles
 and torsion angles; correlations between esds in cell parameters are only
 used when they are defined by crystal symmetry.  An approximate (isotropic)
 treatment of cell esds is used for estimating esds involving l.s. planes.
;
loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_distance
_geom_bond_site_symmetry_2
_geom_bond_publ_flag
Br1 C16 1.896(2) . ?
Br2 C10 1.902(3) . ?
O1 C1 1.449(3) . ?
O1 C2 1.333(3) . ?
O2 C2 1.203(3) . ?
O3 C5 1.213(3) . ?
O4 C5 1.334(3) . ?
O4 C6 1.453(3) . ?
C1 H1A 0.9800 . ?
C1 H1B 0.9800 . ?
C1 H1C 0.9800 . ?
C2 C3 1.508(3) . ?
C3 C4 1.345(4) . ?
C3 C7 1.486(3) . ?
C4 C5 1.501(3) . ?
C4 C13 1.485(3) . ?
C6 H6A 0.9800 . ?
C6 H6B 0.9800 . ?
C6 H6C 0.9800 . ?
C7 C8 1.390(4) . ?
C7 C12 1.397(4) . ?
C8 H8 0.9500 . ?
C8 C9 1.393(4) . ?
C9 H9 0.9500 . ?
C9 C10 1.383(4) . ?
C10 C11 1.384(4) . ?
C11 H11 0.9500 . ?
C11 C12 1.391(4) . ?
C12 H12 0.9500 . ?
C13 C14 1.396(4) . ?
C13 C18 1.391(4) . ?
C14 H14 0.9500 . ?
C14 C15 1.383(4) . ?
C15 H15 0.9500 . ?
C15 C16 1.385(4) . ?
C16 C17 1.382(4) . ?
C17 H17 0.9500 . ?
C17 C18 1.381(4) . ?
C18 H18 0.9500 . ?
Br3 C28 1.898(2) . ?
Br4 C34 1.897(3) . ?
O5 C19 1.446(3) . ?
O5 C20 1.336(3) . ?
O6 C20 1.208(3) . ?
O7 C23 1.205(3) . ?
O8 C23 1.335(3) . ?
O8 C24 1.450(3) . ?
C19 H19A 0.9800 . ?
C19 H19B 0.9800 . ?
C19 H19C 0.9800 . ?
C20 C21 1.501(4) . ?
C21 C22 1.340(4) . ?
C21 C25 1.492(3) . ?
C22 C23 1.505(3) . ?
C22 C31 1.483(4) . ?
C24 H24A 0.9800 . ?
C24 H24B 0.9800 . ?
C24 H24C 0.9800 . ?
C25 C26 1.384(4) . ?
C25 C30 1.398(4) . ?
C26 H26 0.9500 . ?
C26 C27 1.394(4) . ?
C27 H27 0.9500 . ?
C27 C28 1.382(4) . ?
C28 C29 1.377(4) . ?
C29 H29 0.9500 . ?
C29 C30 1.381(4) . ?
C30 H30 0.9500 . ?
C31 C32 1.399(4) . ?
C31 C36 1.392(4) . ?
C32 H32 0.9500 . ?
C32 C33 1.381(4) . ?
C33 H33 0.9500 . ?
C33 C34 1.387(4) . ?
C34 C35 1.379(4) . ?
C35 H35 0.9500 . ?
C35 C36 1.381(4) . ?
C36 H36 0.9500 . ?

loop_
_geom_angle_atom_site_label_1
_geom_angle_atom_site_label_2
_geom_angle_atom_site_label_3
_geom_angle
_geom_angle_site_symmetry_1
_geom_angle_site_symmetry_3
_geom_angle_publ_flag
C2 O1 C1 115.1(2) . . ?
C5 O4 C6 114.7(2) . . ?
O1 C1 H1A 109.5 . . ?
O1 C1 H1B 109.5 . . ?
O1 C1 H1C 109.5 . . ?
H1A C1 H1B 109.5 . . ?
H1A C1 H1C 109.5 . . ?
H1B C1 H1C 109.5 . . ?
O1 C2 C3 111.7(2) . . ?
O2 C2 O1 125.0(2) . . ?
O2 C2 C3 123.2(2) . . ?
C4 C3 C2 121.5(2) . . ?
C4 C3 C7 124.3(2) . . ?
C7 C3 C2 114.3(2) . . ?
C3 C4 C5 118.1(2) . . ?
C3 C4 C13 121.8(2) . . ?
C13 C4 C5 120.1(2) . . ?
O3 C5 O4 123.9(2) . . ?
O3 C5 C4 123.4(2) . . ?
O4 C5 C4 112.8(2) . . ?
O4 C6 H6A 109.5 . . ?
O4 C6 H6B 109.5 . . ?
O4 C6 H6C 109.5 . . ?
H6A C6 H6B 109.5 . . ?
H6A C6 H6C 109.5 . . ?
H6B C6 H6C 109.5 . . ?
C8 C7 C3 120.9(2) . . ?
C8 C7 C12 118.6(2) . . ?
C12 C7 C3 120.4(2) . . ?
C7 C8 H8 119.5 . . ?
C7 C8 C9 121.0(2) . . ?
C9 C8 H8 119.5 . . ?
C8 C9 H9 120.6 . . ?
C10 C9 C8 118.9(2) . . ?
C10 C9 H9 120.6 . . ?
C9 C10 Br2 119.17(19) . . ?
C9 C10 C11 121.7(2) . . ?
C11 C10 Br2 119.2(2) . . ?
C10 C11 H11 120.7 . . ?
C10 C11 C12 118.7(2) . . ?
C12 C11 H11 120.7 . . ?
C7 C12 H12 119.4 . . ?
C11 C12 C7 121.1(2) . . ?
C11 C12 H12 119.4 . . ?
C14 C13 C4 119.5(2) . . ?
C18 C13 C4 121.8(2) . . ?
C18 C13 C14 118.7(2) . . ?
C13 C14 H14 119.4 . . ?
C15 C14 C13 121.2(2) . . ?
C15 C14 H14 119.4 . . ?
C14 C15 H15 120.7 . . ?
C14 C15 C16 118.6(2) . . ?
C16 C15 H15 120.7 . . ?
C15 C16 Br1 119.34(19) . . ?
C17 C16 Br1 119.16(19) . . ?
C17 C16 C15 121.5(2) . . ?
C16 C17 H17 120.4 . . ?
C18 C17 C16 119.2(2) . . ?
C18 C17 H17 120.4 . . ?
C13 C18 H18 119.6 . . ?
C17 C18 C13 120.9(2) . . ?
C17 C18 H18 119.6 . . ?
C20 O5 C19 115.38(19) . . ?
C23 O8 C24 114.5(2) . . ?
O5 C19 H19A 109.5 . . ?
O5 C19 H19B 109.5 . . ?
O5 C19 H19C 109.5 . . ?
H19A C19 H19B 109.5 . . ?
H19A C19 H19C 109.5 . . ?
H19B C19 H19C 109.5 . . ?
O5 C20 C21 111.6(2) . . ?
O6 C20 O5 124.0(2) . . ?
O6 C20 C21 124.4(2) . . ?
C22 C21 C20 118.6(2) . . ?
C22 C21 C25 123.2(2) . . ?
C25 C21 C20 118.2(2) . . ?
C21 C22 C23 121.1(2) . . ?
C21 C22 C31 125.9(2) . . ?
C31 C22 C23 112.8(2) . . ?
O7 C23 O8 124.4(2) . . ?
O7 C23 C22 123.8(2) . . ?
O8 C23 C22 111.6(2) . . ?
O8 C24 H24A 109.5 . . ?
O8 C24 H24B 109.5 . . ?
O8 C24 H24C 109.5 . . ?
H24A C24 H24B 109.5 . . ?
H24A C24 H24C 109.5 . . ?
H24B C24 H24C 109.5 . . ?
C26 C25 C21 120.6(2) . . ?
C26 C25 C30 119.7(2) . . ?
C30 C25 C21 119.7(2) . . ?
C25 C26 H26 119.7 . . ?
C25 C26 C27 120.6(2) . . ?
C27 C26 H26 119.7 . . ?
C26 C27 H27 120.8 . . ?
C28 C27 C26 118.4(2) . . ?
C28 C27 H27 120.8 . . ?
C27 C28 Br3 118.09(19) . . ?
C29 C28 Br3 120.10(19) . . ?
C29 C28 C27 121.8(2) . . ?
C28 C29 H29 120.3 . . ?
C28 C29 C30 119.5(2) . . ?
C30 C29 H29 120.3 . . ?
C25 C30 H30 120.0 . . ?
C29 C30 C25 119.9(2) . . ?
C29 C30 H30 120.0 . . ?
C32 C31 C22 121.3(2) . . ?
C36 C31 C22 120.0(2) . . ?
C36 C31 C32 118.4(2) . . ?
C31 C32 H32 119.6 . . ?
C33 C32 C31 120.7(3) . . ?
C33 C32 H32 119.6 . . ?
C32 C33 H33 120.3 . . ?
C32 C33 C34 119.3(2) . . ?
C34 C33 H33 120.3 . . ?
C33 C34 Br4 119.1(2) . . ?
C35 C34 Br4 119.8(2) . . ?
C35 C34 C33 121.1(3) . . ?
C34 C35 H35 120.5 . . ?
C34 C35 C36 119.1(3) . . ?
C36 C35 H35 120.5 . . ?
C31 C36 H36 119.3 . . ?
C35 C36 C31 121.3(2) . . ?
C35 C36 H36 119.3 . . ?

loop_
_geom_torsion_atom_site_label_1
_geom_torsion_atom_site_label_2
_geom_torsion_atom_site_label_3
_geom_torsion_atom_site_label_4
_geom_torsion
_geom_torsion_site_symmetry_1
_geom_torsion_site_symmetry_2
_geom_torsion_site_symmetry_3
_geom_torsion_site_symmetry_4
_geom_torsion_publ_flag
Br1 C16 C17 C18 179.1(2) . . . . ?
Br2 C10 C11 C12 -179.65(19) . . . . ?
O1 C2 C3 C4 95.6(3) . . . . ?
O1 C2 C3 C7 -84.3(3) . . . . ?
O2 C2 C3 C4 -88.8(3) . . . . ?
O2 C2 C3 C7 91.3(3) . . . . ?
C1 O1 C2 O2 10.7(4) . . . . ?
C1 O1 C2 C3 -173.8(2) . . . . ?
C2 C3 C4 C5 -7.7(4) . . . . ?
C2 C3 C4 C13 171.3(2) . . . . ?
C2 C3 C7 C8 -50.1(3) . . . . ?
C2 C3 C7 C12 128.5(2) . . . . ?
C3 C4 C5 O3 -4.9(4) . . . . ?
C3 C4 C5 O4 175.5(2) . . . . ?
C3 C4 C13 C14 -53.4(4) . . . . ?
C3 C4 C13 C18 123.9(3) . . . . ?
C3 C7 C8 C9 179.6(2) . . . . ?
C3 C7 C12 C11 -178.3(2) . . . . ?
C4 C3 C7 C8 130.0(3) . . . . ?
C4 C3 C7 C12 -51.5(4) . . . . ?
C4 C13 C14 C15 175.4(2) . . . . ?
C4 C13 C18 C17 -175.3(2) . . . . ?
C5 C4 C13 C14 125.6(3) . . . . ?
C5 C4 C13 C18 -57.1(3) . . . . ?
C6 O4 C5 O3 1.2(4) . . . . ?
C6 O4 C5 C4 -179.1(2) . . . . ?
C7 C3 C4 C5 172.3(2) . . . . ?
C7 C3 C4 C13 -8.7(4) . . . . ?
C7 C8 C9 C10 -1.8(4) . . . . ?
C8 C7 C12 C11 0.3(4) . . . . ?
C8 C9 C10 Br2 -179.14(19) . . . . ?
C8 C9 C10 C11 1.4(4) . . . . ?
C9 C10 C11 C12 -0.2(4) . . . . ?
C10 C11 C12 C7 -0.7(4) . . . . ?
C12 C7 C8 C9 1.0(4) . . . . ?
C13 C4 C5 O3 176.0(2) . . . . ?
C13 C4 C5 O4 -3.6(3) . . . . ?
C13 C14 C15 C16 0.5(4) . . . . ?
C14 C13 C18 C17 2.0(4) . . . . ?
C14 C15 C16 Br1 -179.05(19) . . . . ?
C14 C15 C16 C17 1.0(4) . . . . ?
C15 C16 C17 C18 -1.0(4) . . . . ?
C16 C17 C18 C13 -0.6(4) . . . . ?
C18 C13 C14 C15 -1.9(4) . . . . ?
Br3 C28 C29 C30 176.2(2) . . . . ?
Br4 C34 C35 C36 176.66(19) . . . . ?
O5 C20 C21 C22 -162.6(2) . . . . ?
O5 C20 C21 C25 19.8(3) . . . . ?
O6 C20 C21 C22 19.0(4) . . . . ?
O6 C20 C21 C25 -158.6(3) . . . . ?
C19 O5 C20 O6 4.9(4) . . . . ?
C19 O5 C20 C21 -173.5(2) . . . . ?
C20 C21 C22 C23 6.8(4) . . . . ?
C20 C21 C22 C31 -168.5(2) . . . . ?
C20 C21 C25 C26 58.6(3) . . . . ?
C20 C21 C25 C30 -123.8(3) . . . . ?
C21 C22 C23 O7 -115.8(3) . . . . ?
C21 C22 C23 O8 69.8(3) . . . . ?
C21 C22 C31 C32 39.9(4) . . . . ?
C21 C22 C31 C36 -145.8(3) . . . . ?
C21 C25 C26 C27 175.2(2) . . . . ?
C21 C25 C30 C29 -176.2(2) . . . . ?
C22 C21 C25 C26 -118.9(3) . . . . ?
C22 C21 C25 C30 58.7(4) . . . . ?
C22 C31 C32 C33 174.1(2) . . . . ?
C22 C31 C36 C35 -174.3(2) . . . . ?
C23 C22 C31 C32 -135.6(2) . . . . ?
C23 C22 C31 C36 38.6(3) . . . . ?
C24 O8 C23 O7 6.0(4) . . . . ?
C24 O8 C23 C22 -179.6(2) . . . . ?
C25 C21 C22 C23 -175.8(2) . . . . ?
C25 C21 C22 C31 9.0(4) . . . . ?
C25 C26 C27 C28 0.6(4) . . . . ?
C26 C25 C30 C29 1.4(4) . . . . ?
C26 C27 C28 Br3 -177.1(2) . . . . ?
C26 C27 C28 C29 2.2(4) . . . . ?
C27 C28 C29 C30 -3.2(4) . . . . ?
C28 C29 C30 C25 1.3(4) . . . . ?
C30 C25 C26 C27 -2.4(4) . . . . ?
C31 C22 C23 O7 60.0(3) . . . . ?
C31 C22 C23 O8 -114.4(2) . . . . ?
C31 C32 C33 C34 -0.6(4) . . . . ?
C32 C31 C36 C35 0.1(4) . . . . ?
C32 C33 C34 Br4 -176.78(19) . . . . ?
C32 C33 C34 C35 1.6(4) . . . . ?
C33 C34 C35 C36 -1.8(4) . . . . ?
C34 C35 C36 C31 0.9(4) . . . . ?
C36 C31 C32 C33 -0.2(4) . . . . ?

_olex2_exptl_crystal_mounting_method 'Mounted on a nylon loop'
_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 2.381
_oxdiff_exptl_absorpt_empirical_full_min 0.590
####################################################################### 
# 
# This file contains crystal structure data downloaded from the 
# Cambridge Structural Database (CSD) hosted by the Cambridge 
# Crystallographic Data Centre (CCDC).
# 
# Full information about CCDC data access policies and citation 
# guidelines are available at http://www.ccdc.cam.ac.uk/access/V1 
# 
# Audit and citation data items may have been added by the CCDC. 
# Please retain this information to preserve the provenance of 
# this file and to allow appropriate attribution of the data. 
# 
#######################################################################

data_ska-meaze-2_auto
_database_code_depnum_ccdc_archive 'CCDC 2493473'
loop_
_audit_author_name
_audit_author_address
'Vikas Tyagi'
;Thapar Institute of Engineering and Technology
India
;
_audit_update_record             
;
2025-10-06 deposited with the CCDC.	2026-06-05 downloaded from the CCDC.
;
_audit_creation_date             2025-08-01
_audit_creation_method           
;
Olex2 1.5
(compiled 2025.07.13 svn.rb7424aed for OlexSys, GUI svn.r7314)
;
_shelx_SHELXL_version_number     2019/2
_chemical_name_common            ?
_chemical_name_systematic        ?
_chemical_formula_moiety         'C18 H16 N2 O4'
_chemical_formula_sum            'C18 H16 N2 O4'
_chemical_formula_weight         324.33
_chemical_melting_point          ?
_chemical_oxdiff_formula         'C H N O'
_chemical_oxdiff_usercomment     'yellow block'
loop_
_atom_type_symbol
_atom_type_description
_atom_type_scat_dispersion_real
_atom_type_scat_dispersion_imag
_atom_type_scat_source
C C 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
N N 0.0061 0.0033 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
O O 0.0106 0.0060 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'

_shelx_space_group_comment       
;
The symmetry employed for this shelxl refinement is uniquely defined
by the following loop, which should always be used as a source of
symmetry information in preference to the above space-group names.
They are only intended as comments.
;
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_H-M_alt        'P 1 21/c 1'
_space_group_name_Hall           '-P 2ybc'
loop_
_space_group_symop_operation_xyz
'x, y, z'
'-x, y+1/2, -z+1/2'
'-x, -y, -z'
'x, -y-1/2, z-1/2'

_cell_length_a                   8.8787(5)
_cell_length_b                   11.4494(7)
_cell_length_c                   8.0683(5)
_cell_angle_alpha                90
_cell_angle_beta                 102.012(6)
_cell_angle_gamma                90
_cell_volume                     802.23(8)
_cell_formula_units_Z            2
_cell_measurement_reflns_used    5170
_cell_measurement_temperature    100.2(4)
_cell_measurement_theta_max      31.0730
_cell_measurement_theta_min      3.5750
_shelx_estimated_absorpt_T_max   0.987
_shelx_estimated_absorpt_T_min   0.983
_exptl_absorpt_coefficient_mu    0.096
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.01156
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   
;
CrysAlisPro 1.171.42.89a (Rigaku Oxford Diffraction, 2023)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_absorpt_special_details   ?
_exptl_crystal_colour            'clear light yellow'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   light
_exptl_crystal_colour_primary    yellow
_exptl_crystal_density_diffrn    1.343
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    ?
_exptl_crystal_description       block
_exptl_crystal_F_000             340
_exptl_crystal_preparation       'As per the reaction scheme'
_exptl_crystal_recrystallization_method 'Slow evaporation method'
_exptl_crystal_size_max          0.18
_exptl_crystal_size_mid          0.16
_exptl_crystal_size_min          0.14
_exptl_transmission_factor_max   ?
_exptl_transmission_factor_min   ?
_diffrn_reflns_av_R_equivalents  0.0528
_diffrn_reflns_av_unetI/netI     0.0469
_diffrn_reflns_Laue_measured_fraction_full 0.997
_diffrn_reflns_Laue_measured_fraction_max 0.831
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -10
_diffrn_reflns_number            9469
_diffrn_reflns_point_group_measured_fraction_full 0.997
_diffrn_reflns_point_group_measured_fraction_max 0.831
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         30.889
_diffrn_reflns_theta_min         3.559
_diffrn_ambient_environment      N~2~
_diffrn_ambient_temperature      100.2(4)
_diffrn_detector                 'Hybrid Pixel Array Detector'
_diffrn_detector_area_resol_mean 5.8140
_diffrn_detector_type            'Pilatus 200K'
_diffrn_measured_fraction_theta_full 0.9956
_diffrn_measured_fraction_theta_max 0.8287
_diffrn_measurement_details      
;
List of Runs (angles in degrees, time in seconds):

  # Type    Start    End  Width  tₑₓₚ   ω     θ     κ     φ   Frames
#--------------------------------------------------------------------------
  1  ω    -70.00  -1.00   0.50    2.72    --   -5.17 -44.00-166.00  138
  2  ω    -28.00  21.00   0.50    2.72    --   -5.17  77.00  30.00   98
  3  ω    -15.00  30.00   0.50    2.72    --   -5.17 -99.00   0.00   90
  4  ω    -28.00  21.00   0.50    2.72    --   -5.17  77.00 -90.00   98
  5  ω     -9.00  60.00   0.50    2.72    --   -5.17  44.00 -16.00  138
  6  ω     -7.00  51.00   0.50    2.72    --    4.07  57.00  90.00  116
  7  ω    -28.00  21.00   0.50    2.72    --   -5.17  77.00-180.00   98
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  
'SuperNova, Dual, Cu at home/near, Pilatus 200K'
_diffrn_measurement_method       'ω scans'
_diffrn_orient_matrix_type       
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      0.0646747000
_diffrn_orient_matrix_UB_12      0.0010232000
_diffrn_orient_matrix_UB_13      0.0684994000
_diffrn_orient_matrix_UB_21      0.0408457000
_diffrn_orient_matrix_UB_22      0.0344546000
_diffrn_orient_matrix_UB_23      -0.0489713000
_diffrn_orient_matrix_UB_31      -0.0286665000
_diffrn_orient_matrix_UB_32      0.0514788000
_diffrn_orient_matrix_UB_33      0.0313984000
_diffrn_oxdiff_digest_frames     
;
01a7fb4e32a14abc2ed4cdb72edcf382c100026cd67
;
_diffrn_oxdiff_digest_hkl        
;
01ae1edb940b8a2e33c1f48c9f5322774a3ffc
;
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_source                   'micro-focus sealed X-ray tube'
_diffrn_source_type              'SuperNova (Mo) X-ray Source'
_reflns_Friedel_coverage         0.000
_reflns_Friedel_fraction_full    .
_reflns_Friedel_fraction_max     .
_reflns_number_gt                1700
_reflns_number_total             2099
_reflns_special_details          
;
 Reflections were merged by SHELXL according to the crystal
 class for the calculation of statistics and refinement.
 
 _reflns_Friedel_fraction is defined as the number of unique
 Friedel pairs measured divided by the number that would be
 possible theoretically, ignoring centric projections and
 systematic absences.
;
_reflns_threshold_expression     'I > 2σ(I)'
_computing_cell_refinement       'CrysAlisPro 1.171.42.89a (Rigaku OD, 2023)'
_computing_data_collection       'CrysAlisPro 1.171.42.89a (Rigaku OD, 2023)'
_computing_data_reduction        'CrysAlisPro 1.171.42.89a (Rigaku OD, 2023)'
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2019/2 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT 2014/5 (Sheldrick, 2014)'
_refine_diff_density_max         0.964
_refine_diff_density_min         -0.233
_refine_diff_density_rms         0.059
_refine_ls_extinction_coef       .
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.090
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     110
_refine_ls_number_reflns         2099
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0627
_refine_ls_R_factor_gt           0.0512
_refine_ls_restrained_S_all      1.090
_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/[σ²(Fo²)+(0.0722P)²+0.2463P] where P=(Fo²+2Fc²)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1359
_refine_ls_wR_factor_ref         0.1440
_refine_special_details          ?
_olex2_refinement_description    
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2.a Aromatic/amide H refined with riding coordinates:
 C5(H5), C6(H6), C7(H7), C8(H8), C9(H9)
2.b Idealised Me refined as rotating group:
 C1(H1A,H1B,H1C)
;
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_atom_sites_solution_secondary   ?
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
_atom_site_adp_type
_atom_site_occupancy
_atom_site_site_symmetry_order
_atom_site_calc_flag
_atom_site_refinement_flags_posn
_atom_site_refinement_flags_adp
_atom_site_refinement_flags_occupancy
_atom_site_disorder_assembly
_atom_site_disorder_group
O1 O 0.23076(12) 0.34939(9) 0.02716(14) 0.0244(3) Uani 1 1 d . . . . .
O2 O 0.14171(11) 0.52006(10) -0.09549(13) 0.0245(3) Uani 1 1 d . . . . .
N1 N 0.50245(13) 0.52558(10) 0.07975(15) 0.0187(3) Uani 1 1 d . . . . .
C1 C 0.10652(19) 0.28867(16) -0.0851(2) 0.0338(4) Uani 1 1 d . . . . .
H1A H 0.109326 0.307078 -0.202996 0.051 Uiso 1 1 calc R U . . .
H1B H 0.007637 0.313642 -0.061133 0.051 Uiso 1 1 calc R U . . .
H1C H 0.118673 0.204271 -0.066850 0.051 Uiso 1 1 calc R U . . .
C2 C 0.23432(15) 0.46449(13) 0.00362(17) 0.0191(3) Uani 1 1 d . . . . .
C3 C 0.37096(15) 0.51888(11) 0.12282(17) 0.0174(3) Uani 1 1 d . . . . .
C4 C 0.35041(15) 0.56542(12) 0.28602(17) 0.0174(3) Uani 1 1 d . . . . .
C5 C 0.21357(16) 0.54463(13) 0.34186(18) 0.0212(3) Uani 1 1 d . . . . .
H5 H 0.131521 0.503552 0.271441 0.025 Uiso 1 1 calc R U . . .
C6 C 0.19790(17) 0.58413(13) 0.50032(19) 0.0241(3) Uani 1 1 d . . . . .
H6 H 0.106029 0.568034 0.538981 0.029 Uiso 1 1 calc R U . . .
C7 C 0.31531(18) 0.64686(13) 0.60242(19) 0.0235(3) Uani 1 1 d . . . . .
H7 H 0.303660 0.674127 0.710248 0.028 Uiso 1 1 calc R U . . .
C8 C 0.45041(17) 0.66968(12) 0.54605(18) 0.0217(3) Uani 1 1 d . . . . .
H8 H 0.530403 0.713602 0.615037 0.026 Uiso 1 1 calc R U . . .
C9 C 0.46868(16) 0.62869(12) 0.39005(18) 0.0189(3) Uani 1 1 d . . . . .
H9 H 0.561808 0.643508 0.353296 0.023 Uiso 1 1 calc R U . . .


_geom_special_details            
;
 All esds (except the esd in the dihedral angle between two l.s. planes)
 are estimated using the full covariance matrix.  The cell esds are taken
 into account individually in the estimation of esds in distances, angles
 and torsion angles; correlations between esds in cell parameters are only
 used when they are defined by crystal symmetry.  An approximate (isotropic)
 treatment of cell esds is used for estimating esds involving l.s. planes.
;
loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_distance
_geom_bond_site_symmetry_2
_geom_bond_publ_flag
O1 C1 1.4505(18) . ?
O1 C2 1.3328(18) . ?
O2 C2 1.2027(18) . ?
N1 N1 1.406(2) 3_665 ?
N1 C3 1.2879(18) . ?
C1 H1A 0.9800 . ?
C1 H1B 0.9800 . ?
C1 H1C 0.9800 . ?
C2 C3 1.5162(18) . ?
C3 C4 1.4666(19) . ?
C4 C5 1.4013(19) . ?
C4 C9 1.4018(19) . ?
C5 H5 0.9500 . ?
C5 C6 1.390(2) . ?
C6 H6 0.9500 . ?
C6 C7 1.387(2) . ?
C7 H7 0.9500 . ?
C7 C8 1.393(2) . ?
C8 H8 0.9500 . ?
C8 C9 1.384(2) . ?
C9 H9 0.9500 . ?

loop_
_geom_angle_atom_site_label_1
_geom_angle_atom_site_label_2
_geom_angle_atom_site_label_3
_geom_angle
_geom_angle_site_symmetry_1
_geom_angle_site_symmetry_3
_geom_angle_publ_flag
C2 O1 C1 114.99(12) . . ?
C3 N1 N1 111.40(13) . 3_665 ?
O1 C1 H1A 109.5 . . ?
O1 C1 H1B 109.5 . . ?
O1 C1 H1C 109.5 . . ?
H1A C1 H1B 109.5 . . ?
H1A C1 H1C 109.5 . . ?
H1B C1 H1C 109.5 . . ?
O1 C2 C3 110.81(12) . . ?
O2 C2 O1 125.77(13) . . ?
O2 C2 C3 123.41(13) . . ?
N1 C3 C2 120.26(12) . . ?
N1 C3 C4 120.65(12) . . ?
C4 C3 C2 119.08(11) . . ?
C5 C4 C3 120.34(12) . . ?
C5 C4 C9 119.13(13) . . ?
C9 C4 C3 120.51(12) . . ?
C4 C5 H5 120.0 . . ?
C6 C5 C4 119.99(13) . . ?
C6 C5 H5 120.0 . . ?
C5 C6 H6 119.7 . . ?
C7 C6 C5 120.53(13) . . ?
C7 C6 H6 119.7 . . ?
C6 C7 H7 120.2 . . ?
C6 C7 C8 119.67(13) . . ?
C8 C7 H7 120.2 . . ?
C7 C8 H8 119.8 . . ?
C9 C8 C7 120.33(13) . . ?
C9 C8 H8 119.8 . . ?
C4 C9 H9 119.8 . . ?
C8 C9 C4 120.32(13) . . ?
C8 C9 H9 119.8 . . ?

loop_
_geom_torsion_atom_site_label_1
_geom_torsion_atom_site_label_2
_geom_torsion_atom_site_label_3
_geom_torsion_atom_site_label_4
_geom_torsion
_geom_torsion_site_symmetry_1
_geom_torsion_site_symmetry_2
_geom_torsion_site_symmetry_3
_geom_torsion_site_symmetry_4
_geom_torsion_publ_flag
O1 C2 C3 N1 87.73(15) . . . . ?
O1 C2 C3 C4 -93.34(15) . . . . ?
O2 C2 C3 N1 -93.52(17) . . . . ?
O2 C2 C3 C4 85.41(17) . . . . ?
N1 N1 C3 C2 -1.9(2) 3_665 . . . ?
N1 N1 C3 C4 179.15(13) 3_665 . . . ?
N1 C3 C4 C5 -171.71(13) . . . . ?
N1 C3 C4 C9 6.7(2) . . . . ?
C1 O1 C2 O2 3.2(2) . . . . ?
C1 O1 C2 C3 -178.14(12) . . . . ?
C2 C3 C4 C5 9.36(19) . . . . ?
C2 C3 C4 C9 -172.25(12) . . . . ?
C3 C4 C5 C6 176.85(13) . . . . ?
C3 C4 C9 C8 -178.21(12) . . . . ?
C4 C5 C6 C7 1.7(2) . . . . ?
C5 C4 C9 C8 0.2(2) . . . . ?
C5 C6 C7 C8 -0.5(2) . . . . ?
C6 C7 C8 C9 -0.9(2) . . . . ?
C7 C8 C9 C4 1.0(2) . . . . ?
C9 C4 C5 C6 -1.6(2) . . . . ?

_olex2_exptl_crystal_mounting_method 'Mounted on a nylon loop'
_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 24.097
_oxdiff_exptl_absorpt_empirical_full_min 0.622
####################################################################### 
# 
# This file contains crystal structure data downloaded from the 
# Cambridge Structural Database (CSD) hosted by the Cambridge 
# Crystallographic Data Centre (CCDC).
# 
# Full information about CCDC data access policies and citation 
# guidelines are available at http://www.ccdc.cam.ac.uk/access/V1 
# 
# Audit and citation data items may have been added by the CCDC. 
# Please retain this information to preserve the provenance of 
# this file and to allow appropriate attribution of the data. 
# 
#######################################################################

data_ska-172-s1-4br
_database_code_depnum_ccdc_archive 'CCDC 2493475'
loop_
_audit_author_name
_audit_author_address
'Vikas Tyagi'
;Thapar Institute of Engineering and Technology
India
;
_audit_update_record             
;
2025-10-06 deposited with the CCDC.	2026-06-05 downloaded from the CCDC.
;
_audit_creation_date             2025-08-01
_audit_creation_method           
;
Olex2 1.5
(compiled 2025.07.13 svn.rb7424aed for OlexSys, GUI svn.r7314)
;
_shelx_SHELXL_version_number     2019/2
_chemical_name_common            ?
_chemical_name_systematic        ?
_chemical_formula_moiety         'C18 H14 Br2 O4'
_chemical_formula_sum            'C18 H14 Br2 O4'
_chemical_formula_weight         454.11
_chemical_melting_point          ?
_chemical_oxdiff_formula         'C H N O Br'
_chemical_oxdiff_usercomment     'colourless block'
loop_
_atom_type_symbol
_atom_type_description
_atom_type_scat_dispersion_real
_atom_type_scat_dispersion_imag
_atom_type_scat_source
C C 0.0033 0.0016 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
H H 0.0000 0.0000 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
Br Br -0.2901 2.4595 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
O O 0.0106 0.0060 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'

_shelx_space_group_comment       
;
The symmetry employed for this shelxl refinement is uniquely defined
by the following loop, which should always be used as a source of
symmetry information in preference to the above space-group names.
They are only intended as comments.
;
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_H-M_alt        'P 1 21/n 1'
_space_group_name_Hall           '-P 2yn'
loop_
_space_group_symop_operation_xyz
'x, y, z'
'-x+1/2, y+1/2, -z+1/2'
'-x, -y, -z'
'x-1/2, -y-1/2, z-1/2'

_cell_length_a                   5.9647(2)
_cell_length_b                   18.3812(7)
_cell_length_c                   8.0674(3)
_cell_angle_alpha                90
_cell_angle_beta                 93.059(3)
_cell_angle_gamma                90
_cell_volume                     883.24(6)
_cell_formula_units_Z            2
_cell_measurement_reflns_used    5803
_cell_measurement_temperature    111.44(10)
_cell_measurement_theta_max      29.6320
_cell_measurement_theta_min      4.1810
_cell_oxdiff_angle_alpha         90.033(3)
_cell_oxdiff_angle_beta          93.022(3)
_cell_oxdiff_angle_gamma         89.973(3)
_cell_oxdiff_length_a            5.9647(2)
_cell_oxdiff_length_b            18.3813(6)
_cell_oxdiff_length_c            8.0671(3)
_cell_oxdiff_measurement_reflns_used 5802
_cell_oxdiff_volume              883.24(5)
_shelx_estimated_absorpt_T_max   0.526
_shelx_estimated_absorpt_T_min   0.459
_exptl_absorpt_coefficient_mu    4.607
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.64205
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   
;
CrysAlisPro 1.171.43.90 (Rigaku Oxford Diffraction, 2023)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_absorpt_special_details   ?
_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    1.708
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    ?
_exptl_crystal_description       block
_exptl_crystal_F_000             448
_exptl_crystal_preparation       'As per the reaction scheme'
_exptl_crystal_recrystallization_method 'Slow evaporation method'
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.18
_exptl_crystal_size_min          0.16
_exptl_transmission_factor_max   ?
_exptl_transmission_factor_min   ?
_diffrn_reflns_av_R_equivalents  0.0309
_diffrn_reflns_av_unetI/netI     0.0200
_diffrn_reflns_Laue_measured_fraction_full 0.996
_diffrn_reflns_Laue_measured_fraction_max 0.786
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       22
_diffrn_reflns_limit_k_min       -23
_diffrn_reflns_limit_l_max       9
_diffrn_reflns_limit_l_min       -9
_diffrn_reflns_number            9222
_diffrn_reflns_point_group_measured_fraction_full 0.996
_diffrn_reflns_point_group_measured_fraction_max 0.786
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         29.755
_diffrn_reflns_theta_min         3.596
_diffrn_ambient_environment      N~2~
_diffrn_ambient_temperature      111.44(10)
_diffrn_detector                 'Hybrid Pixel Array Detector'
_diffrn_detector_area_resol_mean 5.8140
_diffrn_detector_type            'Pilatus 200K'
_diffrn_measured_fraction_theta_full 0.9940
_diffrn_measured_fraction_theta_max 0.7852
_diffrn_measurement_details      
;
List of Runs (angles in degrees, time in seconds):

  # Type    Start    End  Width  tₑₓₚ   ω     θ     κ     φ   Frames
#--------------------------------------------------------------------------
  1  ω    -29.00  32.00   0.50   33.10    --    1.16 -90.00-104.00  122
  2  ω    -29.00  29.00   0.50   33.10    --   -2.33 -90.00-104.00  116
  3  ω    -15.00  33.00   0.50   33.10    --   -2.33 -99.00 120.00   96
  4  ω    -42.00  21.00   0.50   33.10    --   -2.33 -77.00   0.00  126
  5  ω    -25.00  21.00   0.50   33.10    --   -2.33  77.00 120.00   92
  6  ω    -68.00   1.00   0.50   33.10    --   -2.33 -38.00-180.00  138
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  
'SuperNova, Dual, Cu at home/near, Pilatus 200K'
_diffrn_measurement_method       'ω scans'
_diffrn_orient_matrix_type       
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      0.0818012000
_diffrn_orient_matrix_UB_12      0.0253960000
_diffrn_orient_matrix_UB_13      0.0302612000
_diffrn_orient_matrix_UB_21      0.0341448000
_diffrn_orient_matrix_UB_22      -0.0244855000
_diffrn_orient_matrix_UB_23      0.0644165000
_diffrn_orient_matrix_UB_31      0.0795185000
_diffrn_orient_matrix_UB_32      -0.0156370000
_diffrn_orient_matrix_UB_33      -0.0518380000
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_source                   'micro-focus sealed X-ray tube'
_diffrn_source_type              'SuperNova (Mo) X-ray Source'
_reflns_Friedel_coverage         0.000
_reflns_Friedel_fraction_full    .
_reflns_Friedel_fraction_max     .
_reflns_number_gt                1817
_reflns_number_total             1985
_reflns_special_details          
;
 Reflections were merged by SHELXL according to the crystal
 class for the calculation of statistics and refinement.
 
 _reflns_Friedel_fraction is defined as the number of unique
 Friedel pairs measured divided by the number that would be
 possible theoretically, ignoring centric projections and
 systematic absences.
;
_reflns_threshold_expression     'I > 2σ(I)'
_computing_cell_refinement       'CrysAlisPro 1.171.43.90 (Rigaku OD, 2023)'
_computing_data_collection       
'CrysAlisPro system (CCD 42.89a 64-bit (release 24-03-2023))'
_computing_data_reduction        'CrysAlisPro 1.171.43.90 (Rigaku OD, 2023)'
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2019/2 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT 2018/2 (Sheldrick, 2018)'
_refine_diff_density_max         0.620
_refine_diff_density_min         -0.297
_refine_diff_density_rms         0.070
_refine_ls_extinction_coef       .
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.052
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     110
_refine_ls_number_reflns         1985
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0281
_refine_ls_R_factor_gt           0.0244
_refine_ls_restrained_S_all      1.052
_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/[σ²(Fo²)+(0.0321P)²+0.5665P] where P=(Fo²+2Fc²)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0598
_refine_ls_wR_factor_ref         0.0609
_refine_special_details          ?
_olex2_refinement_description    
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2.a Aromatic/amide H refined with riding coordinates:
 C5(H5), C6(H6), C2(H2), C3(H3)
2.b Idealised Me refined as rotating group:
 C9(H9A,H9B,H9C)
;
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_atom_sites_solution_secondary   ?
loop_
_atom_site_label
_atom_site_type_symbol
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_U_iso_or_equiv
_atom_site_adp_type
_atom_site_occupancy
_atom_site_site_symmetry_order
_atom_site_calc_flag
_atom_site_refinement_flags_posn
_atom_site_refinement_flags_adp
_atom_site_refinement_flags_occupancy
_atom_site_disorder_assembly
_atom_site_disorder_group
Br1 Br -0.15080(3) 0.24233(2) 0.17205(3) 0.02750(9) Uani 1 1 d . . . . .
O2 O 0.7075(2) 0.43373(7) 0.74398(15) 0.0197(3) Uani 1 1 d . . . . .
O1 O 0.3509(2) 0.45054(8) 0.81362(15) 0.0224(3) Uani 1 1 d . . . . .
C1 C 0.0273(3) 0.31702(10) 0.2748(2) 0.0191(4) Uani 1 1 d . . . . .
C5 C 0.0904(3) 0.40154(10) 0.4974(2) 0.0172(3) Uani 1 1 d . . . . .
H5 H 0.042362 0.424280 0.595151 0.021 Uiso 1 1 calc R U . . .
C8 C 0.4937(3) 0.45171(9) 0.7135(2) 0.0160(3) Uani 1 1 d . . . . .
C6 C -0.0457(3) 0.34988(10) 0.4169(2) 0.0187(4) Uani 1 1 d . . . . .
H6 H -0.186521 0.337237 0.458461 0.022 Uiso 1 1 calc R U . . .
C4 C 0.2967(3) 0.42040(9) 0.4363(2) 0.0161(3) Uani 1 1 d . . . . .
C2 C 0.2287(3) 0.33589(10) 0.2086(2) 0.0204(4) Uani 1 1 d . . . . .
H2 H 0.273897 0.313845 0.109207 0.025 Uiso 1 1 calc R U . . .
C3 C 0.3636(3) 0.38777(10) 0.2905(2) 0.0185(4) Uani 1 1 d . . . . .
H3 H 0.502542 0.401150 0.246789 0.022 Uiso 1 1 calc R U . . .
C7 C 0.4495(3) 0.47119(10) 0.5323(2) 0.0162(3) Uani 1 1 d . . . . .
C9 C 0.7715(4) 0.41417(13) 0.9141(2) 0.0294(5) Uani 1 1 d . . . . .
H9A H 0.933216 0.404550 0.924419 0.044 Uiso 1 1 calc R U . . .
H9B H 0.689393 0.370439 0.944874 0.044 Uiso 1 1 calc R U . . .
H9C H 0.735048 0.454298 0.987994 0.044 Uiso 1 1 calc R U . . .


_geom_special_details            
;
 All esds (except the esd in the dihedral angle between two l.s. planes)
 are estimated using the full covariance matrix.  The cell esds are taken
 into account individually in the estimation of esds in distances, angles
 and torsion angles; correlations between esds in cell parameters are only
 used when they are defined by crystal symmetry.  An approximate (isotropic)
 treatment of cell esds is used for estimating esds involving l.s. planes.
;
loop_
_geom_bond_atom_site_label_1
_geom_bond_atom_site_label_2
_geom_bond_distance
_geom_bond_site_symmetry_2
_geom_bond_publ_flag
Br1 C1 1.8989(18) . ?
O2 C8 1.327(2) . ?
O2 C9 1.450(2) . ?
O1 C8 1.205(2) . ?
C1 C6 1.386(3) . ?
C1 C2 1.385(3) . ?
C5 H5 0.9500 . ?
C5 C6 1.388(2) . ?
C5 C4 1.394(3) . ?
C8 C7 1.515(2) . ?
C6 H6 0.9500 . ?
C4 C3 1.398(2) . ?
C4 C7 1.492(2) . ?
C2 H2 0.9500 . ?
C2 C3 1.392(3) . ?
C3 H3 0.9500 . ?
C7 C7 1.338(4) 3_666 ?
C9 H9A 0.9800 . ?
C9 H9B 0.9800 . ?
C9 H9C 0.9800 . ?

loop_
_geom_angle_atom_site_label_1
_geom_angle_atom_site_label_2
_geom_angle_atom_site_label_3
_geom_angle
_geom_angle_site_symmetry_1
_geom_angle_site_symmetry_3
_geom_angle_publ_flag
C8 O2 C9 116.01(14) . . ?
C6 C1 Br1 118.88(14) . . ?
C2 C1 Br1 119.30(14) . . ?
C2 C1 C6 121.80(17) . . ?
C6 C5 H5 119.7 . . ?
C6 C5 C4 120.65(16) . . ?
C4 C5 H5 119.7 . . ?
O2 C8 C7 110.69(14) . . ?
O1 C8 O2 125.32(16) . . ?
O1 C8 C7 123.94(16) . . ?
C1 C6 C5 118.94(17) . . ?
C1 C6 H6 120.5 . . ?
C5 C6 H6 120.5 . . ?
C5 C4 C3 119.24(16) . . ?
C5 C4 C7 119.90(15) . . ?
C3 C4 C7 120.74(16) . . ?
C1 C2 H2 120.7 . . ?
C1 C2 C3 118.69(16) . . ?
C3 C2 H2 120.7 . . ?
C4 C3 H3 119.7 . . ?
C2 C3 C4 120.64(17) . . ?
C2 C3 H3 119.7 . . ?
C4 C7 C8 115.02(15) . . ?
C7 C7 C8 120.3(2) 3_666 . ?
C7 C7 C4 124.6(2) 3_666 . ?
O2 C9 H9A 109.5 . . ?
O2 C9 H9B 109.5 . . ?
O2 C9 H9C 109.5 . . ?
H9A C9 H9B 109.5 . . ?
H9A C9 H9C 109.5 . . ?
H9B C9 H9C 109.5 . . ?

loop_
_geom_torsion_atom_site_label_1
_geom_torsion_atom_site_label_2
_geom_torsion_atom_site_label_3
_geom_torsion_atom_site_label_4
_geom_torsion
_geom_torsion_site_symmetry_1
_geom_torsion_site_symmetry_2
_geom_torsion_site_symmetry_3
_geom_torsion_site_symmetry_4
_geom_torsion_publ_flag
Br1 C1 C6 C5 176.39(13) . . . . ?
Br1 C1 C2 C3 -176.39(14) . . . . ?
O2 C8 C7 C4 114.02(17) . . . . ?
O2 C8 C7 C7 -63.8(3) . . . 3_666 ?
O1 C8 C7 C4 -63.6(2) . . . . ?
O1 C8 C7 C7 118.6(2) . . . 3_666 ?
C1 C2 C3 C4 -0.2(3) . . . . ?
C5 C4 C3 C2 -1.4(3) . . . . ?
C5 C4 C7 C8 50.5(2) . . . . ?
C5 C4 C7 C7 -131.8(2) . . . 3_666 ?
C6 C1 C2 C3 1.9(3) . . . . ?
C6 C5 C4 C3 1.4(3) . . . . ?
C6 C5 C4 C7 -174.69(16) . . . . ?
C4 C5 C6 C1 0.3(3) . . . . ?
C2 C1 C6 C5 -1.9(3) . . . . ?
C3 C4 C7 C8 -125.49(17) . . . . ?
C3 C4 C7 C7 52.2(3) . . . 3_666 ?
C7 C4 C3 C2 174.65(17) . . . . ?
C9 O2 C8 O1 -2.6(3) . . . . ?
C9 O2 C8 C7 179.75(16) . . . . ?

_olex2_exptl_crystal_mounting_method 'Mounted on a nylon loop'
_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 1.590
_oxdiff_exptl_absorpt_empirical_full_min 0.722
