# 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_cu_250302a_0m
_database_code_depnum_ccdc_archive 'CCDC 2428438'
loop_
_audit_author_name
_audit_author_address
'Yu-Feng Liang'
;Shandong University
China
;
_audit_update_record             
;
2025-03-03 deposited with the CCDC.	2026-03-20 downloaded from the CCDC.
;
_audit_creation_date             2025-03-03
_audit_creation_method           
;
Olex2 1.3
(compiled 2020.11.12 svn.r5f609507 for OlexSys, GUI svn.r6408)
;
_shelx_SHELXL_version_number     2018/3
_chemical_name_common            ?
_chemical_name_systematic        ?
_chemical_formula_moiety         'C12 H15 N O3 Si'
_chemical_formula_sum            'C12 H15 N O3 Si'
_chemical_formula_weight         249.34
_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 0.0181 0.0091 '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 0.0311 0.0180 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
O O 0.0492 0.0322 'International Tables Vol C Tables 4.2.6.8 and 6.1.1.4'
Si Si 0.2541 0.3302 '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                   6.0357(15)
_cell_length_b                   19.028(5)
_cell_length_c                   11.731(3)
_cell_angle_alpha                90
_cell_angle_beta                 92.745(12)
_cell_angle_gamma                90
_cell_volume                     1345.8(5)
_cell_formula_units_Z            4
_cell_measurement_reflns_used    2815
_cell_measurement_temperature    298.0
_cell_measurement_theta_max      66.070
_cell_measurement_theta_min      4.648
_shelx_estimated_absorpt_T_max   0.979
_shelx_estimated_absorpt_T_min   0.953
_exptl_absorpt_coefficient_mu    1.529
_exptl_absorpt_correction_T_max  0.7528
_exptl_absorpt_correction_T_min  0.5220
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.1264 before and 0.0733 after correction.
The Ratio of minimum to maximum transmission is 0.6934.
The λ/2 correction factor is Not present.
;
_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    1.231
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    ?
_exptl_crystal_description       block
_exptl_crystal_F_000             528
_exptl_crystal_size_max          0.032
_exptl_crystal_size_mid          0.025
_exptl_crystal_size_min          0.014
_exptl_transmission_factor_max   ?
_exptl_transmission_factor_min   ?
_diffrn_reflns_av_R_equivalents  0.0568
_diffrn_reflns_av_unetI/netI     0.0564
_diffrn_reflns_Laue_measured_fraction_full 0.987
_diffrn_reflns_Laue_measured_fraction_max 0.987
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -22
_diffrn_reflns_limit_l_max       13
_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            7778
_diffrn_reflns_point_group_measured_fraction_full 0.987
_diffrn_reflns_point_group_measured_fraction_max 0.987
_diffrn_reflns_theta_full        66.560
_diffrn_reflns_theta_max         66.560
_diffrn_reflns_theta_min         4.431
_diffrn_ambient_temperature      298.0
_diffrn_detector_area_resol_mean ?
_diffrn_measured_fraction_theta_full 0.987
_diffrn_measured_fraction_theta_max 0.987
_diffrn_measurement_device_type  'Bruker D8 VENTURE PHOTON III'
_diffrn_measurement_method       ?
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_source                   ?
_diffrn_source_current           1.1
_diffrn_source_power             0.055
_diffrn_source_voltage           50.0
_reflns_Friedel_coverage         0.000
_reflns_Friedel_fraction_full    .
_reflns_Friedel_fraction_max     .
_reflns_number_gt                1841
_reflns_number_total             2344
_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 V8.40B (?, 2016)'
_computing_data_collection       ?
_computing_data_reduction        'SAINT V8.40B (?, 2016)'
_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)'
_refine_diff_density_max         0.220
_refine_diff_density_min         -0.249
_refine_diff_density_rms         0.049
_refine_ls_extinction_coef       .
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.083
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     157
_refine_ls_number_reflns         2344
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0648
_refine_ls_R_factor_gt           0.0499
_refine_ls_restrained_S_all      1.083
_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)+(0.0874P)²+0.0605P] where P=(Fo²+2Fc²)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1396
_refine_ls_wR_factor_ref         0.1526
_refine_special_details          ?
_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:
 C10(H10A,H10B)
2.b Aromatic/amide H refined with riding coordinates:
 C12(H12), C7(H7), C2(H2), C5(H5)
2.c Idealised Me refined as rotating group:
 C3(H3A,H3B,H3C), C9(H9A,H9B,H9C), C11(H11A,H11B,H11C)
;
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     ?
_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
Si1 Si 0.51746(10) 0.45912(3) 0.25118(4) 0.0541(3) Uani 1 1 d . . . . .
O1 O 0.7646(3) 0.57775(8) 0.28881(13) 0.0774(6) Uani 1 1 d . . . . .
O3 O 1.1471(3) 0.58880(9) 0.4386(2) 0.0963(7) Uani 1 1 d . . . . .
O2 O 0.5231(4) 0.70541(10) 0.30850(19) 0.1007(7) Uani 1 1 d . . . . .
N1 N 0.8252(4) 0.63525(9) 0.35562(16) 0.0666(5) Uani 1 1 d . . . . .
C1 C 1.0115(4) 0.70675(11) 0.48109(19) 0.0562(6) Uani 1 1 d . . . . .
C4 C 0.8211(4) 0.74146(11) 0.44339(17) 0.0554(5) Uani 1 1 d . . . . .
C6 C 0.6953(5) 0.69555(12) 0.3607(2) 0.0671(6) Uani 1 1 d . . . . .
C8 C 1.0158(4) 0.63666(11) 0.4256(2) 0.0645(6) Uani 1 1 d . . . . .
C10 C 0.6393(4) 0.52683(11) 0.35323(19) 0.0624(6) Uani 1 1 d . . . . .
H10A H 0.521717 0.550490 0.391711 0.075 Uiso 1 1 calc R U . . .
H10B H 0.736347 0.504236 0.410450 0.075 Uiso 1 1 calc R U . . .
C12 C 0.7694(5) 0.80679(12) 0.4851(2) 0.0706(7) Uani 1 1 d . . . . .
H12 H 0.639591 0.829709 0.460701 0.085 Uiso 1 1 calc R U . . .
C3 C 0.3492(4) 0.39965(13) 0.3386(2) 0.0721(7) Uani 1 1 d . . . . .
H3A H 0.226041 0.425202 0.366690 0.108 Uiso 1 1 calc R U . . .
H3B H 0.439682 0.381978 0.401756 0.108 Uiso 1 1 calc R U . . .
H3C H 0.295220 0.361084 0.292381 0.108 Uiso 1 1 calc R U . . .
C7 C 0.9158(5) 0.83704(13) 0.5639(2) 0.0752(7) Uani 1 1 d . . . . .
H7 H 0.885676 0.881494 0.592237 0.090 Uiso 1 1 calc R U . . .
C2 C 1.1563(5) 0.73693(13) 0.5603(2) 0.0738(7) Uani 1 1 d . . . . .
H2 H 1.285138 0.713743 0.585555 0.089 Uiso 1 1 calc R U . . .
C9 C 0.7457(5) 0.41071(15) 0.1849(2) 0.0810(8) Uani 1 1 d . . . . .
H9A H 0.684431 0.373699 0.137495 0.122 Uiso 1 1 calc R U . . .
H9B H 0.842883 0.390951 0.243592 0.122 Uiso 1 1 calc R U . . .
H9C H 0.827602 0.442466 0.139225 0.122 Uiso 1 1 calc R U . . .
C5 C 1.1057(5) 0.80281(13) 0.6015(2) 0.0769(8) Uani 1 1 d . . . . .
H5 H 1.201465 0.824183 0.655457 0.092 Uiso 1 1 calc R U . . .
C11 C 0.3386(5) 0.50619(14) 0.1439(2) 0.0793(7) Uani 1 1 d . . . . .
H11A H 0.425647 0.540038 0.105027 0.119 Uiso 1 1 calc R U . . .
H11B H 0.221807 0.529835 0.181305 0.119 Uiso 1 1 calc R U . . .
H11C H 0.275580 0.473137 0.089697 0.119 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
Si1 C10 1.884(2) . ?
Si1 C3 1.861(2) . ?
Si1 C9 1.859(2) . ?
Si1 C11 1.850(3) . ?
O1 N1 1.385(2) . ?
O1 C10 1.462(3) . ?
O3 C8 1.212(3) . ?
O2 C6 1.196(3) . ?
N1 C6 1.393(3) . ?
N1 C8 1.381(3) . ?
C1 C4 1.380(3) . ?
C1 C8 1.485(3) . ?
C1 C2 1.371(4) . ?
C4 C6 1.487(3) . ?
C4 C12 1.377(3) . ?
C10 H10A 0.9700 . ?
C10 H10B 0.9700 . ?
C12 H12 0.9300 . ?
C12 C7 1.374(4) . ?
C3 H3A 0.9600 . ?
C3 H3B 0.9600 . ?
C3 H3C 0.9600 . ?
C7 H7 0.9300 . ?
C7 C5 1.373(4) . ?
C2 H2 0.9300 . ?
C2 C5 1.383(4) . ?
C9 H9A 0.9600 . ?
C9 H9B 0.9600 . ?
C9 H9C 0.9600 . ?
C5 H5 0.9300 . ?
C11 H11A 0.9600 . ?
C11 H11B 0.9600 . ?
C11 H11C 0.9600 . ?

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
C3 Si1 C10 105.81(11) . . ?
C9 Si1 C10 109.29(12) . . ?
C9 Si1 C3 111.35(13) . . ?
C11 Si1 C10 107.37(13) . . ?
C11 Si1 C3 110.69(13) . . ?
C11 Si1 C9 112.04(13) . . ?
N1 O1 C10 111.12(15) . . ?
O1 N1 C6 122.8(2) . . ?
C8 N1 O1 122.79(19) . . ?
C8 N1 C6 114.40(19) . . ?
C4 C1 C8 108.7(2) . . ?
C2 C1 C4 120.7(2) . . ?
C2 C1 C8 130.5(2) . . ?
C1 C4 C6 108.6(2) . . ?
C12 C4 C1 121.2(2) . . ?
C12 C4 C6 130.2(2) . . ?
O2 C6 N1 125.8(2) . . ?
O2 C6 C4 130.3(2) . . ?
N1 C6 C4 104.0(2) . . ?
O3 C8 N1 125.5(2) . . ?
O3 C8 C1 130.1(3) . . ?
N1 C8 C1 104.28(19) . . ?
Si1 C10 H10A 109.9 . . ?
Si1 C10 H10B 109.9 . . ?
O1 C10 Si1 108.70(13) . . ?
O1 C10 H10A 109.9 . . ?
O1 C10 H10B 109.9 . . ?
H10A C10 H10B 108.3 . . ?
C4 C12 H12 121.1 . . ?
C7 C12 C4 117.9(3) . . ?
C7 C12 H12 121.1 . . ?
Si1 C3 H3A 109.5 . . ?
Si1 C3 H3B 109.5 . . ?
Si1 C3 H3C 109.5 . . ?
H3A C3 H3B 109.5 . . ?
H3A C3 H3C 109.5 . . ?
H3B C3 H3C 109.5 . . ?
C12 C7 H7 119.4 . . ?
C5 C7 C12 121.2(2) . . ?
C5 C7 H7 119.4 . . ?
C1 C2 H2 120.9 . . ?
C1 C2 C5 118.2(3) . . ?
C5 C2 H2 120.9 . . ?
Si1 C9 H9A 109.5 . . ?
Si1 C9 H9B 109.5 . . ?
Si1 C9 H9C 109.5 . . ?
H9A C9 H9B 109.5 . . ?
H9A C9 H9C 109.5 . . ?
H9B C9 H9C 109.5 . . ?
C7 C5 C2 120.8(3) . . ?
C7 C5 H5 119.6 . . ?
C2 C5 H5 119.6 . . ?
Si1 C11 H11A 109.5 . . ?
Si1 C11 H11B 109.5 . . ?
Si1 C11 H11C 109.5 . . ?
H11A C11 H11B 109.5 . . ?
H11A C11 H11C 109.5 . . ?
H11B C11 H11C 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
O1 N1 C6 O2 -1.3(4) . . . . ?
O1 N1 C6 C4 178.77(17) . . . . ?
O1 N1 C8 O3 -1.6(4) . . . . ?
O1 N1 C8 C1 -179.16(17) . . . . ?
N1 O1 C10 Si1 169.53(16) . . . . ?
C1 C4 C6 O2 -180.0(3) . . . . ?
C1 C4 C6 N1 0.0(2) . . . . ?
C1 C4 C12 C7 1.3(4) . . . . ?
C1 C2 C5 C7 -0.2(4) . . . . ?
C4 C1 C8 O3 -176.3(2) . . . . ?
C4 C1 C8 N1 1.1(2) . . . . ?
C4 C1 C2 C5 0.3(3) . . . . ?
C4 C12 C7 C5 -1.1(4) . . . . ?
C6 N1 C8 O3 176.4(2) . . . . ?
C6 N1 C8 C1 -1.2(3) . . . . ?
C6 C4 C12 C7 178.5(2) . . . . ?
C8 N1 C6 O2 -179.2(3) . . . . ?
C8 N1 C6 C4 0.8(3) . . . . ?
C8 C1 C4 C6 -0.7(2) . . . . ?
C8 C1 C4 C12 177.1(2) . . . . ?
C8 C1 C2 C5 -177.2(2) . . . . ?
C10 O1 N1 C6 -91.7(3) . . . . ?
C10 O1 N1 C8 86.2(3) . . . . ?
C12 C4 C6 O2 2.5(5) . . . . ?
C12 C4 C6 N1 -177.5(2) . . . . ?
C12 C7 C5 C2 0.6(4) . . . . ?
C3 Si1 C10 O1 -177.01(16) . . . . ?
C2 C1 C4 C6 -178.7(2) . . . . ?
C2 C1 C4 C12 -0.9(3) . . . . ?
C2 C1 C8 O3 1.4(4) . . . . ?
C2 C1 C8 N1 178.8(2) . . . . ?
C9 Si1 C10 O1 63.0(2) . . . . ?
C11 Si1 C10 O1 -58.76(19) . . . . ?

_olex2_submission_special_instructions 'No special instructions were received'
