Amidines: a deeper look at the archetypal pro-ligand.
de Vere-Tucker, Matthew; Squire, Imogen; Tritto, Michelangelo; Anandkar, Rohil; Syeda, Tayyibah; Uthayan, Divia; Aguila, Gabrielle; Silva de Moraes, Lygia; Bakewell, Clare; Dalton transactions (Cambridge, England : 2003) 55 (2026) 4977–4987; doi:10.1039/d6dt00276e

data_7720566
_publ_section_title
;
 Amidines: a deeper look at the archetypal pro-ligand.
;
_journal_issue                   12
_journal_name_full
'Dalton transactions (Cambridge, England : 2003)'
_journal_page_first              4977
_journal_page_last               4987
_journal_paper_doi               10.1039/d6dt00276e
_journal_volume                  55
_journal_year                    2026
_chemical_formula_moiety         'C28 H34 N2'
_chemical_formula_sum            'C28 H34 N2'
_chemical_formula_weight         398.57
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2yn'
_space_group_name_H-M_alt        'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_audit_creation_date             2025-12-10
_audit_creation_method
;
Olex2 1.5
(compiled 2025.07.13 svn.rb7424aed for OlexSys, GUI svn.r7314)
;
_audit_update_record
;
2026-01-30 deposited with the CCDC.	2026-03-03 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 99.359(10)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   15.6824(15)
_cell_length_b                   8.9748(8)
_cell_length_c                   16.5729(16)
_cell_measurement_reflns_used    2577
_cell_measurement_temperature    150.00(10)
_cell_measurement_theta_max      28.7150
_cell_measurement_theta_min      3.3420
_cell_volume                     2301.5(4)
_computing_cell_refinement       'CrysAlisPro 1.171.42.49 (Rigaku OD, 2022)'
_computing_data_collection       'CrysAlisPro 1.171.42.49 (Rigaku OD, 2022)'
_computing_data_reduction        'CrysAlisPro 1.171.42.49 (Rigaku OD, 2022)'
_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    'SHELXT 2018/2 (Sheldrick, 2018)'
_diffrn_ambient_environment      N~2~
_diffrn_ambient_temperature      150.00(10)
_diffrn_detector                 'CCD plate'
_diffrn_detector_area_resol_mean 15.9832
_diffrn_detector_type            Sapphire3
_diffrn_measured_fraction_theta_full 0.993
_diffrn_measured_fraction_theta_max 0.827
_diffrn_measurement_details
;
List of Runs (angles in degrees, time in seconds):

  # Type    Start    End  Width  t~exp~   \w     \q     \k     \f   Frames
  1  \w    -36.00  38.00   1.00  687.50    --   15.02 -77.00 -90.00   74
  2  \w      1.00  78.00   1.00  687.50    --   15.02  57.00  30.00   77
  3  \w    -32.00   2.00   1.00  687.50    --  -15.49 -77.00 150.00   34
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'Xcalibur, Sapphire3, Gemini'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_type
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      0.0439433000
_diffrn_orient_matrix_UB_12      -0.0228839000
_diffrn_orient_matrix_UB_13      0.0072425000
_diffrn_orient_matrix_UB_21      0.0131564000
_diffrn_orient_matrix_UB_22      0.0750544000
_diffrn_orient_matrix_UB_23      0.0066878000
_diffrn_orient_matrix_UB_31      -0.0018723000
_diffrn_orient_matrix_UB_32      -0.0081076000
_diffrn_orient_matrix_UB_33      0.0422665000
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0473
_diffrn_reflns_av_unetI/netI     0.0995
_diffrn_reflns_Laue_measured_fraction_full 0.993
_diffrn_reflns_Laue_measured_fraction_max 0.827
_diffrn_reflns_limit_h_max       21
_diffrn_reflns_limit_h_min       -21
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -12
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            9251
_diffrn_reflns_point_group_measured_fraction_full 0.993
_diffrn_reflns_point_group_measured_fraction_max 0.827
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         29.362
_diffrn_reflns_theta_min         3.371
_diffrn_source                   'fine-focus sealed X-ray tube'
_diffrn_source_type              'Enhance (Mo) X-ray Source'
_exptl_absorpt_coefficient_mu    0.066
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.77525
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.42.49 (Rigaku Oxford Diffraction, 2022)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            'clear colourless'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.150
_exptl_crystal_description       irregular
_exptl_crystal_F_000             864
_exptl_crystal_recrystallization_method
'Re-crystallisation from solvent: Ethanol'
_exptl_crystal_size_max          0.3
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.1
_refine_diff_density_max         0.207
_refine_diff_density_min         -0.224
_refine_diff_density_rms         0.043
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.033
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     277
_refine_ls_number_reflns         5227
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.033
_refine_ls_R_factor_all          0.1195
_refine_ls_R_factor_gt           0.0670
_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/[\s^2^(Fo^2^)+(0.0342P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1049
_refine_ls_wR_factor_ref         0.1226
_reflns_Friedel_coverage         0.000
_reflns_number_gt                3345
_reflns_number_total             5227
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d6dt00276e3.cif
_cod_data_source_block           depAmpTolH_19
_cod_depositor_comments
'Adding full bibliography for 7720566--7720581.cif.'
_cod_database_code               7720566
_shelx_shelxl_version_number     2019/3
_chemical_oxdiff_formula         C28H34Al1Cl2N2
_shelx_estimated_absorpt_t_max   0.993
_shelx_estimated_absorpt_t_min   0.980
_diffrn_oxdiff_ac3_digest_hkl    01736c4ec88116ebb37e4b24796929ec2431a9
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups, All N(H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2. Others
 Sof(H2)=1-FVAR(1)
 Sof(H1)=FVAR(1)
3.a Secondary CH2 refined with riding coordinates:
 C15(H15A,H15B), C17(H17A,H17B), C25(H25A,H25B), C27(H27A,H27B)
3.b Aromatic/amide H refined with riding coordinates:
 N2(H2), N1(H1), C21(H21), C3(H3), C23(H23), C7(H7), C22(H22), C13(H13),
 C4(H4), C11(H11), C6(H6), C12(H12)
3.c Idealised Me refined as rotating group:
 C16(H16A,H16B,H16C), C18(H18A,H18B,H18C), C8(H8A,H8B,H8C), C26(H26A,H26B,
 H26C), C28(H28A,H28B,H28C)
;
_shelx_res_checksum              29108
_shelx_hkl_checksum              77372
_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 1.942
_oxdiff_exptl_absorpt_empirical_full_min 0.373