# Supplementary Information (SI) for Chemical Science.
# This journal is © The Royal Society of Chemistry 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_25_12_11_cd
_database_code_depnum_ccdc_archive 'CCDC 2522036'
loop_
_audit_author_name
_audit_author_address
'Qi Wu'
;Wuhan Textile University
China
;
_audit_update_record             
;
2026-01-12 deposited with the CCDC.	2026-05-29 downloaded from the CCDC.
;
_audit_creation_date             2025-12-30
_audit_creation_method           
;
Olex2 1.5
(compiled 2025.07.13 svn.rb7424aed for OlexSys, GUI svn.r7314)
;
_shelx_SHELXL_version_number     2018/3
_chemical_name_common            ?
_chemical_name_systematic        ?
_chemical_formula_moiety         'C4 H2 Cd N2 O2'
_chemical_formula_sum            'C4 H2 Cd N2 O2'
_chemical_formula_weight         222.48
_chemical_absolute_configuration ?
_chemical_melting_point          ?
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'
Cd Cd -0.8075 1.2024 '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      orthorhombic
_space_group_IT_number           33
_space_group_name_H-M_alt        'P n a 21'
_space_group_name_Hall           'P 2c -2n'
loop_
_space_group_symop_operation_xyz
'x, y, z'
'-x, -y, z+1/2'
'x+1/2, -y+1/2, z'
'-x+1/2, y+1/2, z+1/2'

_cell_length_a                   6.9584(6)
_cell_length_b                   10.2697(9)
_cell_length_c                   6.8280(6)
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_volume                     487.93(7)
_cell_formula_units_Z            4
_cell_measurement_reflns_used    5153
_cell_measurement_temperature    304.00
_cell_measurement_theta_max      29.898
_cell_measurement_theta_min      3.537
_shelx_estimated_absorpt_T_max   0.633
_shelx_estimated_absorpt_T_min   0.620
_exptl_absorpt_coefficient_mu    4.371
_exptl_absorpt_correction_T_max  0.8622
_exptl_absorpt_correction_T_min  0.7339
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.1133 before and 0.0595 after correction.
The Ratio of minimum to maximum transmission is 0.8512.
The λ/2 correction factor is Not present.
;
_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    3.029
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    ?
_exptl_crystal_description       block
_exptl_crystal_F_000             416
_exptl_crystal_size_max          0.121
_exptl_crystal_size_mid          0.116
_exptl_crystal_size_min          0.115
_exptl_transmission_factor_max   ?
_exptl_transmission_factor_min   ?
_diffrn_reflns_av_R_equivalents  0.0382
_diffrn_reflns_av_unetI/netI     0.0261
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 1.000
_diffrn_reflns_limit_h_max       8
_diffrn_reflns_limit_h_min       -8
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            7537
_diffrn_reflns_point_group_measured_fraction_full 0.994
_diffrn_reflns_point_group_measured_fraction_max 0.992
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         25.958
_diffrn_reflns_theta_min         3.537
_diffrn_ambient_temperature      304.00
_diffrn_detector_area_resol_mean ?
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'BURKER D8 QUEST'
_diffrn_measurement_method       ?
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_source                   ?
_diffrn_source_current           1.4
_diffrn_source_power             0.07
_diffrn_source_voltage           50.0
_reflns_Friedel_coverage         0.820
_reflns_Friedel_fraction_full    0.988
_reflns_Friedel_fraction_max     0.982
_reflns_number_gt                895
_reflns_number_total             952
_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       'SAINT V8.41 (?, 2016)'
_computing_data_collection       ?
_computing_data_reduction        'SAINT V8.41 (?, 2016)'
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2018/3 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT  (Sheldrick, 2015)'
_refine_diff_density_max         0.406
_refine_diff_density_min         -0.499
_refine_diff_density_rms         0.119
_refine_ls_abs_structure_details 
;
 Flack x determined using 367 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.05(3)
_refine_ls_extinction_coef       .
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.214
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     82
_refine_ls_number_reflns         952
_refine_ls_number_restraints     1
_refine_ls_R_factor_all          0.0251
_refine_ls_R_factor_gt           0.0221
_refine_ls_restrained_S_all      1.213
_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)+(0.0193P)²+0.1575P] where P=(Fo²+2Fc²)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0438
_refine_ls_wR_factor_ref         0.0451
_refine_special_details          ?
_olex2_refinement_description    
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups
2.a Aromatic/amide H refined with riding coordinates:
 C2(H2), C1(H1)
;
_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
Cd1 Cd 0.85545(5) 0.09587(3) 0.08179(12) 0.01610(16) Uani 1 1 d . . . . .
N1 N 0.8393(7) 0.2263(5) 0.3296(8) 0.0160(12) Uani 1 1 d . . . . .
O2 O 0.5728(7) 0.4288(4) 0.8439(7) 0.0209(11) Uani 1 1 d . . . . .
O1 O 0.6198(6) 0.2209(4) 0.9187(7) 0.0215(11) Uani 1 1 d . . . . .
C3 C 0.7357(8) 0.3012(6) 0.6144(10) 0.0117(17) Uani 1 1 d . . . . .
N2 N 0.7766(8) 0.4072(5) 0.5001(8) 0.0171(12) Uani 1 1 d . . . . .
C2 C 0.7760(9) 0.1918(6) 0.5113(9) 0.0146(14) Uani 1 1 d . . . . .
H2 H 0.762614 0.106936 0.557034 0.018 Uiso 1 1 calc R U . . .
C1 C 0.8377(9) 0.3564(7) 0.3306(11) 0.0200(15) Uani 1 1 d . . . . .
H1 H 0.875304 0.406722 0.224080 0.024 Uiso 1 1 calc R U . . .
C4 C 0.6408(8) 0.3153(7) 0.8061(10) 0.0164(15) Uani 1 1 d . . . . .

loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_23
_atom_site_aniso_U_13
_atom_site_aniso_U_12
Cd1 0.0233(2) 0.0131(2) 0.0119(2) -0.0023(4) 0.0026(5) -0.00039(17)
N1 0.018(3) 0.015(3) 0.014(3) -0.003(3) 0.000(2) 0.001(2)
O2 0.026(3) 0.017(2) 0.020(3) -0.002(2) 0.008(2) 0.003(2)
O1 0.027(3) 0.023(3) 0.015(2) 0.009(2) -0.0012(19) 0.000(2)
C3 0.013(3) 0.012(3) 0.010(5) 0.002(3) -0.001(3) 0.003(2)
N2 0.018(3) 0.017(3) 0.016(3) 0.000(2) 0.003(2) 0.003(2)
C2 0.014(3) 0.014(3) 0.016(3) 0.003(3) 0.002(2) 0.008(3)
C1 0.025(4) 0.021(4) 0.014(4) 0.002(3) 0.002(3) 0.003(3)
C4 0.016(4) 0.018(4) 0.014(3) -0.003(3) -0.004(3) 0.000(3)

_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
Cd1 N1 2.161(6) . ?
Cd1 O2 2.234(5) 3_554 ?
Cd1 O2 2.529(5) 4_644 ?
Cd1 O1 2.361(4) 1_554 ?
Cd1 N2 2.216(5) 4_644 ?
N1 C2 1.363(8) . ?
N1 C1 1.336(9) . ?
O2 C4 1.284(8) . ?
O1 C4 1.246(8) . ?
C3 N2 1.369(8) . ?
C3 C2 1.356(8) . ?
C3 C4 1.473(10) . ?
N2 C1 1.339(9) . ?
C2 H2 0.9300 . ?
C1 H1 0.9300 . ?

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
N1 Cd1 O2 132.43(18) . 3_554 ?
N1 Cd1 O2 82.93(18) . 4_644 ?
N1 Cd1 O1 89.78(18) . 1_554 ?
N1 Cd1 N2 135.8(2) . 4_644 ?
O2 Cd1 O2 107.70(6) 3_554 4_644 ?
O2 Cd1 O1 100.88(17) 3_554 1_554 ?
O1 Cd1 O2 147.09(15) 1_554 4_644 ?
N2 Cd1 O2 70.51(17) 4_644 4_644 ?
N2 Cd1 O2 89.93(19) 4_644 3_554 ?
N2 Cd1 O1 93.94(17) 4_644 1_554 ?
C2 N1 Cd1 124.6(4) . . ?
C1 N1 Cd1 128.6(5) . . ?
C1 N1 C2 104.6(6) . . ?
Cd1 O2 Cd1 136.5(2) 3_456 4_655 ?
C4 O2 Cd1 113.6(4) . 4_655 ?
C4 O2 Cd1 107.0(4) . 3_456 ?
C4 O1 Cd1 129.3(4) . 1_556 ?
N2 C3 C4 121.5(6) . . ?
C2 C3 N2 108.7(6) . . ?
C2 C3 C4 129.4(6) . . ?
C3 N2 Cd1 117.7(4) . 4_655 ?
C1 N2 Cd1 133.6(5) . 4_655 ?
C1 N2 C3 104.4(6) . . ?
N1 C2 H2 125.6 . . ?
C3 C2 N1 108.9(6) . . ?
C3 C2 H2 125.6 . . ?
N1 C1 N2 113.4(7) . . ?
N1 C1 H1 123.3 . . ?
N2 C1 H1 123.3 . . ?
O2 C4 C3 115.6(6) . . ?
O1 C4 O2 122.6(6) . . ?
O1 C4 C3 121.6(6) . . ?

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
Cd1 N1 C2 C3 -163.7(4) . . . . ?
Cd1 N1 C1 N2 163.4(4) . . . . ?
Cd1 O2 C4 O1 -16.1(7) 3_456 . . . ?
Cd1 O2 C4 O1 179.9(5) 4_655 . . . ?
Cd1 O2 C4 C3 -3.7(6) 4_655 . . . ?
Cd1 O2 C4 C3 160.3(4) 3_456 . . . ?
Cd1 O1 C4 O2 -118.7(6) 1_556 . . . ?
Cd1 O1 C4 C3 65.1(8) 1_556 . . . ?
Cd1 N2 C1 N1 -155.7(5) 4_655 . . . ?
C3 N2 C1 N1 -0.3(8) . . . . ?
N2 C3 C2 N1 -1.2(7) . . . . ?
N2 C3 C4 O2 10.5(9) . . . . ?
N2 C3 C4 O1 -173.0(6) . . . . ?
C2 N1 C1 N2 -0.4(7) . . . . ?
C2 C3 N2 Cd1 160.9(4) . . . 4_655 ?
C2 C3 N2 C1 0.9(7) . . . . ?
C2 C3 C4 O2 -161.0(6) . . . . ?
C2 C3 C4 O1 15.4(10) . . . . ?
C1 N1 C2 C3 0.9(7) . . . . ?
C4 C3 N2 Cd1 -12.2(8) . . . 4_655 ?
C4 C3 N2 C1 -172.3(5) . . . . ?
C4 C3 C2 N1 171.3(6) . . . . ?

_shelx_res_file                  
;
TITL 25_12_11_cd_a.res in Pna2(1)
    25_12_11_cd.res
    created by SHELXL-2018/3 at 20:18:11 on 30-Dec-2025
REM Old TITL 25_12_11_cd_a.res in Pna2(1)
REM SHELXT solution in Pna2(1): R1 0.064, Rweak 0.002, Alpha 0.007
REM <I/s> 1.656 for 80 systematic absences, Orientation as input
REM Flack x = 0.035 ( 0.027 ) from 397 Parsons' quotients
REM Formula found by SHELXT: C4 N2 O2 Cd
CELL 0.71073 6.9584 10.2697 6.828 90 90 90
ZERR 4 0.0006 0.0009 0.0006 0 0 0
LATT -1
SYMM -X,-Y,0.5+Z
SYMM 0.5+X,0.5-Y,+Z
SYMM 0.5-X,0.5+Y,0.5+Z
SFAC C H Cd N O
UNIT 16 8 4 8 8

L.S. 30 0 0
PLAN  20
SIZE 0.116 0.121 0.115
TEMP 30.85
CONF
BOND
list 4
MORE -1
BOND $H
fmap 2 53
acta
SHEL 999 0.81
REM <olex2.extras>
REM <HklSrc "%.\\25_12_11_CD.hkl">
REM </olex2.extras>

WGHT    0.019300    0.157500
FVAR       0.64245
CD1   3    0.855446    0.095872    0.081792    11.00000    0.02327    0.01313 =
         0.01191   -0.00227    0.00256   -0.00039
N1    4    0.839283    0.226305    0.329630    11.00000    0.01837    0.01550 =
         0.01402   -0.00310    0.00013    0.00091
O2    5    0.572845    0.428752    0.843875    11.00000    0.02637    0.01684 =
         0.01962   -0.00190    0.00798    0.00275
O1    5    0.619801    0.220875    0.918702    11.00000    0.02701    0.02260 =
         0.01491    0.00870   -0.00120   -0.00046
C3    1    0.735658    0.301242    0.614401    11.00000    0.01280    0.01221 =
         0.01012    0.00155   -0.00134    0.00258
N2    4    0.776609    0.407178    0.500132    11.00000    0.01792    0.01730 =
         0.01613   -0.00004    0.00285    0.00333
C2    1    0.775972    0.191753    0.511293    11.00000    0.01432    0.01400 =
         0.01556    0.00261    0.00220    0.00794
AFIX  43
H2    2    0.762614    0.106936    0.557034    11.00000   -1.20000
AFIX   0
C1    1    0.837687    0.356403    0.330635    11.00000    0.02479    0.02100 =
         0.01434    0.00230    0.00158    0.00283
AFIX  43
H1    2    0.875304    0.406722    0.224080    11.00000   -1.20000
AFIX   0
C4    1    0.640755    0.315297    0.806080    11.00000    0.01634    0.01842 =
         0.01435   -0.00270   -0.00422    0.00037
HKLF 4




REM  25_12_11_cd_a.res in Pna2(1)
REM wR2 = 0.0451, GooF = S = 1.214, Restrained GooF = 1.213 for all data
REM R1 = 0.0221 for 895 Fo > 4sig(Fo) and 0.0251 for all 952 data
REM 82 parameters refined using 1 restraints

END

WGHT      0.0193      0.1575

REM Highest difference peak  0.406,  deepest hole -0.499,  1-sigma level  0.119
Q1    1   0.6559  0.4390  0.2862  11.00000  0.05    0.41
Q2    1   1.0619  0.4748  0.1845  11.00000  0.05    0.37
Q3    1   0.7750  0.2988  0.6823  11.00000  0.05    0.36
Q4    1   0.8623  0.0456  0.6809  11.00000  0.05    0.35
Q5    1   0.8718  0.2869  0.8043  11.00000  0.05    0.35
Q6    1   0.4607  0.3780  0.6889  11.00000  0.05    0.35
Q7    1   0.8418  0.2599  0.5761  11.00000  0.05    0.33
Q8    1   0.5258  0.1619  0.9159  11.00000  0.05    0.32
Q9    1   0.6914  0.2400  0.1644  11.00000  0.05    0.31
Q10   1   0.4144  0.3331  0.8313  11.00000  0.05    0.31
Q11   1   0.6796  0.4405  0.1655  11.00000  0.05    0.31
Q12   1   0.8888  0.3860  0.7202  11.00000  0.05    0.31
Q13   1   0.8961  0.2188  0.7188  11.00000  0.05    0.30
Q14   1   0.7934  0.3208  0.0770  11.00000  0.05    0.30
Q15   1   0.6007 -0.0183  0.4230  11.00000  0.05    0.29
Q16   1   0.8652  0.4158  0.6935  11.00000  0.05    0.28
Q17   1   0.7225  0.0055  0.5610  11.00000  0.05    0.28
Q18   1   0.8077  0.1527  0.6809  11.00000  0.05    0.28
Q19   1   1.0276  0.3582  0.2408  11.00000  0.05    0.27
Q20   1   1.0403  0.3022  0.3693  11.00000  0.05    0.27
;
_shelx_res_checksum              69331
_olex2_submission_special_instructions 'No special instructions were received'
