# Supplementary Information (SI) for ChemComm.
# 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. 
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data_rc1205_a
_database_code_depnum_ccdc_archive 'CCDC 2483689'
loop_
_audit_author_name
_audit_author_address
'Raju Chouhan'
;Tezpur University
India
;
_audit_update_record             
;
2025-08-29 deposited with the CCDC.	2025-12-12 downloaded from the CCDC.
;
_audit_creation_date             2025-08-04
_audit_creation_method           
;
Olex2 1.5
(compiled 2024.02.16 svn.r378c4104 for OlexSys, GUI svn.r6928)
;
_shelx_SHELXL_version_number     2019/3
_chemical_name_common            ?
_chemical_name_systematic        Rc1205
_chemical_formula_moiety         'C21 H18 N2'
_chemical_formula_sum            'C21 H18 N2'
_chemical_formula_weight         298.37
_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'
N N 0.0061 0.0033 '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           19
_space_group_name_H-M_alt        'P 21 21 21'
_space_group_name_Hall           'P 2ac 2ab'
loop_
_space_group_symop_operation_xyz
'x, y, z'
'-x+1/2, -y, z+1/2'
'-x, y+1/2, -z+1/2'
'x+1/2, -y+1/2, -z'

_cell_length_a                   6.466(11)
_cell_length_b                   12.77(2)
_cell_length_c                   19.58(3)
_cell_angle_alpha                90
_cell_angle_beta                 90
_cell_angle_gamma                90
_cell_volume                     1616(5)
_cell_formula_units_Z            4
_cell_measurement_reflns_used    178
_cell_measurement_temperature    296.15
_cell_measurement_theta_max      11.47
_cell_measurement_theta_min      3.32
_shelx_estimated_absorpt_T_max   0.992
_shelx_estimated_absorpt_T_min   0.989
_exptl_absorpt_coefficient_mu    0.072
_exptl_absorpt_correction_T_max  0.7457
_exptl_absorpt_correction_T_min  0.3577
_exptl_absorpt_correction_type   none
_exptl_absorpt_process_details   
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.1526 before and 0.0945 after correction.
The Ratio of minimum to maximum transmission is 0.4797.
The λ/2 correction factor is Not present.
;
_exptl_absorpt_special_details   ?
_exptl_crystal_colour            'clear light brown'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   light
_exptl_crystal_colour_primary    brown
_exptl_crystal_density_diffrn    1.226
_exptl_crystal_density_meas      ?
_exptl_crystal_density_method    ?
_exptl_crystal_description       block
_exptl_crystal_F_000             632
_exptl_crystal_preparation       ?
_exptl_crystal_recrystallization_method ?
_exptl_crystal_size_max          0.16
_exptl_crystal_size_mid          0.13
_exptl_crystal_size_min          0.11
_exptl_transmission_factor_max   ?
_exptl_transmission_factor_min   ?
_diffrn_reflns_av_R_equivalents  0.2463
_diffrn_reflns_av_unetI/netI     0.3101
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.998
_diffrn_reflns_limit_h_max       7
_diffrn_reflns_limit_h_min       -7
_diffrn_reflns_limit_k_max       12
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       23
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            9991
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.997
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         25.679
_diffrn_reflns_theta_min         1.904
_diffrn_ambient_temperature      296.15
_diffrn_detector_area_resol_mean ?
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       'φ and ω scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_source                   ?
_diffrn_source_current           0.0
_diffrn_source_power             0.0
_diffrn_source_voltage           0.0
_diffrn_standards_number         0
_reflns_Friedel_coverage         0.713
_reflns_Friedel_fraction_full    0.999
_reflns_Friedel_fraction_max     0.995
_reflns_number_gt                1162
_reflns_number_total             3069
_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 V8.38A (Bruker, 2018)'
_computing_data_collection       ?
_computing_data_reduction        'SAINT V8.38A (Bruker, 2018)'
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2019/3 (Sheldrick, 2015)'
_computing_structure_solution    ?
_refine_diff_density_max         0.313
_refine_diff_density_min         -0.280
_refine_diff_density_rms         0.074
_refine_ls_abs_structure_details 
;
 Flack x determined using 260 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   10.0(10)
_refine_ls_extinction_coef       0.022(6)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2019/2 (Sheldrick 2019)'
_refine_ls_goodness_of_fit_ref   0.935
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     212
_refine_ls_number_reflns         3069
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.2388
_refine_ls_R_factor_gt           0.0831
_refine_ls_restrained_S_all      0.935
_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)+(0.0190P)²] where P=(Fo²+2Fc²)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1625
_refine_ls_wR_factor_ref         0.2361
_refine_special_details          ?
_olex2_refinement_description    
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups, All N(H) groups
2.a Ternary CH refined with riding coordinates:
 C1(H1A)
2.b Secondary CH2 refined with riding coordinates:
 C9(H9A,H9B)
2.c Aromatic/amide H refined with riding coordinates:
 N2(H2), C15(H15), C13(H13), C12(H12), C4(H4), C14(H14), C20(H20), C17(H17),
 C19(H19), C7(H7), C6(H6), C21(H21), C18(H18), C5(H5)
;
_atom_sites_solution_hydrogens   mixed
_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
N2 N 0.7802(11) 0.7696(5) 0.4488(4) 0.033(2) Uani 1 1 d . . . . .
H2 H 0.871244 0.797030 0.475355 0.039 Uiso 1 1 calc R U . . .
N1 N 0.6650(12) 0.5994(6) 0.4928(4) 0.032(2) Uani 1 1 d . . . . .
H1 H 0.746(14) 0.607(6) 0.528(4) 0.039 Uiso 1 1 d . U . . .
C1 C 0.7833(13) 0.6586(6) 0.4393(4) 0.029(2) Uani 1 1 d . . . . .
H1A H 0.927441 0.634887 0.440272 0.034 Uiso 1 1 calc R U . . .
C11 C 0.6387(13) 0.8356(7) 0.4176(5) 0.028(2) Uani 1 1 d . . . . .
C3 C 0.6250(15) 0.5072(7) 0.3923(5) 0.030(2) Uani 1 1 d . . . . .
C10 C 0.4869(14) 0.7959(7) 0.3738(4) 0.030(2) Uani 1 1 d . . . . .
C8 C 0.6237(14) 0.4996(7) 0.4635(5) 0.033(3) Uani 1 1 d . . . . .
C15 C 0.3529(14) 0.8667(7) 0.3413(5) 0.033(2) Uani 1 1 d . . . . .
H15 H 0.255093 0.840583 0.310877 0.039 Uiso 1 1 calc R U . . .
C9 C 0.4709(14) 0.6803(6) 0.3627(5) 0.034(3) Uani 1 1 d . . . . .
H9A H 0.417444 0.667999 0.317129 0.041 Uiso 1 1 calc R U . . .
H9B H 0.371605 0.652020 0.394929 0.041 Uiso 1 1 calc R U . . .
C13 C 0.5091(16) 1.0120(7) 0.3981(5) 0.038(3) Uani 1 1 d . . . . .
H13 H 0.516681 1.083445 0.407169 0.045 Uiso 1 1 calc R U . . .
C12 C 0.6453(14) 0.9442(6) 0.4298(5) 0.033(2) Uani 1 1 d . . . . .
H12 H 0.743349 0.970855 0.459918 0.039 Uiso 1 1 calc R U . . .
C16 C 0.8248(15) 0.6292(7) 0.3096(5) 0.033(2) Uani 1 1 d . . . . .
C4 C 0.5712(15) 0.4209(7) 0.3524(5) 0.040(3) Uani 1 1 d . . . . .
H4 H 0.574324 0.425193 0.305019 0.048 Uiso 1 1 calc R U . . .
C14 C 0.3605(15) 0.9745(8) 0.3527(5) 0.041(3) Uani 1 1 d . . . . .
H14 H 0.269527 1.019810 0.330752 0.049 Uiso 1 1 calc R U . . .
C2 C 0.6808(15) 0.6187(7) 0.3708(5) 0.032(2) Uani 1 1 d . . . . .
C20 C 0.9514(16) 0.7204(8) 0.2093(5) 0.043(3) Uani 1 1 d . . . . .
H20 H 0.945490 0.777663 0.180012 0.052 Uiso 1 1 calc R U . . .
C17 C 0.9758(16) 0.5533(7) 0.2991(5) 0.040(3) Uani 1 1 d . . . . .
H17 H 0.989258 0.497795 0.329574 0.048 Uiso 1 1 calc R U . . .
C19 C 1.0957(16) 0.6428(8) 0.1980(6) 0.046(3) Uani 1 1 d . . . . .
H19 H 1.183733 0.646427 0.160545 0.055 Uiso 1 1 calc R U . . .
C7 C 0.5677(14) 0.4079(7) 0.4975(5) 0.039(3) Uani 1 1 d . . . . .
H7 H 0.566249 0.404155 0.544976 0.047 Uiso 1 1 calc R U . . .
C6 C 0.5134(15) 0.3210(7) 0.4567(5) 0.043(3) Uani 1 1 d . . . . .
H6 H 0.477694 0.258340 0.477866 0.051 Uiso 1 1 calc R U . . .
C21 C 0.8115(16) 0.7138(8) 0.2653(5) 0.045(3) Uani 1 1 d . . . . .
H21 H 0.712398 0.765519 0.272032 0.054 Uiso 1 1 calc R U . . .
C18 C 1.1081(16) 0.5605(8) 0.2423(5) 0.044(3) Uani 1 1 d . . . . .
H18 H 1.205839 0.508318 0.234843 0.053 Uiso 1 1 calc R U . . .
C5 C 0.5117(15) 0.3265(7) 0.3851(5) 0.044(3) Uani 1 1 d . . . . .
H5 H 0.471850 0.268735 0.359339 0.052 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
N2 H2 0.8600 . ?
N2 C1 1.430(9) . ?
N2 C11 1.385(10) . ?
N1 H1 0.86(9) . ?
N1 C1 1.500(11) . ?
N1 C8 1.423(11) . ?
C1 H1A 0.9800 . ?
C1 C2 1.580(12) . ?
C11 C10 1.398(12) . ?
C11 C12 1.407(11) . ?
C3 C8 1.399(12) . ?
C3 C4 1.394(11) . ?
C3 C2 1.528(12) . ?
C10 C15 1.404(11) . ?
C10 C9 1.495(11) . ?
C8 C7 1.394(11) . ?
C15 H15 0.9300 . ?
C15 C14 1.396(12) . ?
C9 H9A 0.9700 . ?
C9 H9B 0.9700 . ?
C9 C2 1.576(12) . ?
C13 H13 0.9300 . ?
C13 C12 1.383(12) . ?
C13 C14 1.394(13) . ?
C12 H12 0.9300 . ?
C16 C2 1.523(12) . ?
C16 C17 1.392(12) . ?
C16 C21 1.388(12) . ?
C4 H4 0.9300 . ?
C4 C5 1.417(12) . ?
C14 H14 0.9300 . ?
C20 H20 0.9300 . ?
C20 C19 1.378(13) . ?
C20 C21 1.424(13) . ?
C17 H17 0.9300 . ?
C17 C18 1.405(13) . ?
C19 H19 0.9300 . ?
C19 C18 1.364(12) . ?
C7 H7 0.9300 . ?
C7 C6 1.411(12) . ?
C6 H6 0.9300 . ?
C6 C5 1.404(13) . ?
C21 H21 0.9300 . ?
C18 H18 0.9300 . ?
C5 H5 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
C1 N2 H2 118.2 . . ?
C11 N2 H2 118.2 . . ?
C11 N2 C1 123.7(8) . . ?
C1 N1 H1 101(6) . . ?
C8 N1 H1 122(6) . . ?
C8 N1 C1 105.4(7) . . ?
N2 C1 N1 113.6(7) . . ?
N2 C1 H1A 108.4 . . ?
N2 C1 C2 115.0(7) . . ?
N1 C1 H1A 108.4 . . ?
N1 C1 C2 102.5(7) . . ?
C2 C1 H1A 108.4 . . ?
N2 C11 C10 120.9(8) . . ?
N2 C11 C12 120.2(9) . . ?
C10 C11 C12 118.8(9) . . ?
C8 C3 C2 109.9(8) . . ?
C4 C3 C8 120.1(9) . . ?
C4 C3 C2 129.9(9) . . ?
C11 C10 C15 118.6(8) . . ?
C11 C10 C9 119.7(8) . . ?
C15 C10 C9 121.7(8) . . ?
C3 C8 N1 109.8(8) . . ?
C7 C8 N1 127.5(9) . . ?
C7 C8 C3 122.4(9) . . ?
C10 C15 H15 118.7 . . ?
C14 C15 C10 122.7(9) . . ?
C14 C15 H15 118.7 . . ?
C10 C9 H9A 108.6 . . ?
C10 C9 H9B 108.6 . . ?
C10 C9 C2 114.7(8) . . ?
H9A C9 H9B 107.6 . . ?
C2 C9 H9A 108.6 . . ?
C2 C9 H9B 108.6 . . ?
C12 C13 H13 119.7 . . ?
C12 C13 C14 120.7(9) . . ?
C14 C13 H13 119.7 . . ?
C11 C12 H12 119.3 . . ?
C13 C12 C11 121.4(9) . . ?
C13 C12 H12 119.3 . . ?
C17 C16 C2 119.0(8) . . ?
C21 C16 C2 121.5(9) . . ?
C21 C16 C17 119.5(10) . . ?
C3 C4 H4 120.4 . . ?
C3 C4 C5 119.1(9) . . ?
C5 C4 H4 120.4 . . ?
C15 C14 H14 121.1 . . ?
C13 C14 C15 117.7(9) . . ?
C13 C14 H14 121.1 . . ?
C3 C2 C1 99.5(7) . . ?
C3 C2 C9 106.8(7) . . ?
C9 C2 C1 106.6(7) . . ?
C16 C2 C1 112.5(7) . . ?
C16 C2 C3 116.2(8) . . ?
C16 C2 C9 113.8(8) . . ?
C19 C20 H20 119.6 . . ?
C19 C20 C21 120.7(10) . . ?
C21 C20 H20 119.6 . . ?
C16 C17 H17 120.1 . . ?
C16 C17 C18 119.9(9) . . ?
C18 C17 H17 120.1 . . ?
C20 C19 H19 120.3 . . ?
C18 C19 C20 119.4(10) . . ?
C18 C19 H19 120.3 . . ?
C8 C7 H7 121.5 . . ?
C8 C7 C6 117.0(9) . . ?
C6 C7 H7 121.5 . . ?
C7 C6 H6 119.1 . . ?
C5 C6 C7 121.9(9) . . ?
C5 C6 H6 119.1 . . ?
C16 C21 C20 119.2(9) . . ?
C16 C21 H21 120.4 . . ?
C20 C21 H21 120.4 . . ?
C17 C18 H18 119.4 . . ?
C19 C18 C17 121.2(10) . . ?
C19 C18 H18 119.4 . . ?
C4 C5 H5 120.3 . . ?
C6 C5 C4 119.4(10) . . ?
C6 C5 H5 120.3 . . ?

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
N2 C1 C2 C3 -155.8(7) . . . . ?
N2 C1 C2 C9 -44.9(10) . . . . ?
N2 C1 C2 C16 80.5(9) . . . . ?
N2 C11 C10 C15 -177.3(8) . . . . ?
N2 C11 C10 C9 2.6(12) . . . . ?
N2 C11 C12 C13 178.5(8) . . . . ?
N1 C1 C2 C3 -32.0(8) . . . . ?
N1 C1 C2 C9 78.9(7) . . . . ?
N1 C1 C2 C16 -155.7(8) . . . . ?
N1 C8 C7 C6 173.5(9) . . . . ?
C1 N2 C11 C10 0.0(13) . . . . ?
C1 N2 C11 C12 179.7(8) . . . . ?
C1 N1 C8 C3 -24.7(10) . . . . ?
C1 N1 C8 C7 161.7(9) . . . . ?
C11 N2 C1 N1 -94.1(10) . . . . ?
C11 N2 C1 C2 23.6(12) . . . . ?
C11 C10 C15 C14 -2.3(13) . . . . ?
C11 C10 C9 C2 -28.6(11) . . . . ?
C3 C8 C7 C6 0.6(15) . . . . ?
C3 C4 C5 C6 -1.7(15) . . . . ?
C10 C11 C12 C13 -1.9(14) . . . . ?
C10 C15 C14 C13 0.4(14) . . . . ?
C10 C9 C2 C1 47.3(10) . . . . ?
C10 C9 C2 C3 153.1(8) . . . . ?
C10 C9 C2 C16 -77.3(10) . . . . ?
C8 N1 C1 N2 160.3(7) . . . . ?
C8 N1 C1 C2 35.5(8) . . . . ?
C8 C3 C4 C5 1.2(15) . . . . ?
C8 C3 C2 C1 18.8(10) . . . . ?
C8 C3 C2 C9 -92.0(9) . . . . ?
C8 C3 C2 C16 139.8(9) . . . . ?
C8 C7 C6 C5 -1.1(15) . . . . ?
C15 C10 C9 C2 151.3(8) . . . . ?
C9 C10 C15 C14 177.8(9) . . . . ?
C12 C11 C10 C15 3.0(13) . . . . ?
C12 C11 C10 C9 -177.1(8) . . . . ?
C12 C13 C14 C15 0.8(13) . . . . ?
C16 C17 C18 C19 2.0(14) . . . . ?
C4 C3 C8 N1 -174.6(8) . . . . ?
C4 C3 C8 C7 -0.7(16) . . . . ?
C4 C3 C2 C1 -164.2(10) . . . . ?
C4 C3 C2 C9 85.1(12) . . . . ?
C4 C3 C2 C16 -43.1(14) . . . . ?
C14 C13 C12 C11 -0.1(14) . . . . ?
C2 C3 C8 N1 2.8(11) . . . . ?
C2 C3 C8 C7 176.7(8) . . . . ?
C2 C3 C4 C5 -175.6(9) . . . . ?
C2 C16 C17 C18 179.0(8) . . . . ?
C2 C16 C21 C20 179.3(9) . . . . ?
C20 C19 C18 C17 0.3(14) . . . . ?
C17 C16 C2 C1 80.7(10) . . . . ?
C17 C16 C2 C3 -33.1(12) . . . . ?
C17 C16 C2 C9 -157.9(8) . . . . ?
C17 C16 C21 C20 0.8(14) . . . . ?
C19 C20 C21 C16 1.5(15) . . . . ?
C7 C6 C5 C4 1.7(16) . . . . ?
C21 C16 C2 C1 -97.8(10) . . . . ?
C21 C16 C2 C3 148.4(9) . . . . ?
C21 C16 C2 C9 23.7(12) . . . . ?
C21 C16 C17 C18 -2.5(13) . . . . ?
C21 C20 C19 C18 -2.0(14) . . . . ?

_olex2_submission_special_instructions 'No special instructions were received'
