Metal ligand cooperativity in the direct carboxylation and esterification of terminal alkynes by Cu-CNC complexes bearing 2,6-lutidine linkers.
Back, Nick; Guthrie, Emylie; Zhu, Chengxu; de Visser, Sam P.; Tahsini, Laleh; Chemical science 17 (2026) 2087–2101; doi:10.1039/d5sc08379f

data_1576740
_publ_section_title
;
 Metal ligand cooperativity in the direct carboxylation and esterification
 of terminal alkynes by Cu-CNC complexes bearing 2,6-lutidine linkers.
;
_journal_issue                   4
_journal_name_full               'Chemical science'
_journal_page_first              2087
_journal_page_last               2101
_journal_paper_doi               10.1039/d5sc08379f
_journal_volume                  17
_journal_year                    2026
_chemical_formula_moiety         'C78 H76 Cu2 N10, 2(C2 H3 N)'
_chemical_formula_sum            'C82 H82 Cu2 N12'
_chemical_formula_weight         1362.67
_chemical_name_systematic        '[Cu(IMesC^N^C)(PA)]'
_chemical_properties_physical    Air-sensitive,Moisture-sensitive
_space_group_crystal_system      triclinic
_space_group_IT_number           2
_space_group_name_Hall           '-P 1'
_space_group_name_H-M_alt        'P -1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_audit_creation_date             2025-08-22
_audit_creation_method
;
Olex2 1.5
(compiled 2025.07.13 svn.rb7424aed for OlexSys, GUI svn.r7314)
;
_audit_update_record
;
2025-12-09 deposited with the CCDC.	2026-01-08 downloaded from the CCDC.
;
_cell_angle_alpha                90.952(2)
_cell_angle_beta                 94.577(2)
_cell_angle_gamma                95.280(2)
_cell_formula_units_Z            1
_cell_length_a                   8.3559(4)
_cell_length_b                   11.2732(6)
_cell_length_c                   19.0233(8)
_cell_measurement_reflns_used    9931
_cell_measurement_temperature    100.00
_cell_measurement_theta_max      27.407
_cell_measurement_theta_min      2.456
_cell_volume                     1778.14(15)
_computing_cell_refinement       'SAINT V8.41 (Bruker AXS Inc, 2024)'
_computing_data_reduction        'SAINT V8.41 (Bruker AXS Inc, 2024)'
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'XL  (Sheldrick, 2008)'
_computing_structure_solution    'SHELXT 2018/2 (Sheldrick, 2018)'
_diffrn_ambient_temperature      100.00
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker D8 Venture DUO with Photon 3'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0617
_diffrn_reflns_av_unetI/netI     0.0420
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 0.999
_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       14
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
_diffrn_reflns_number            47397
_diffrn_reflns_point_group_measured_fraction_full 1.000
_diffrn_reflns_point_group_measured_fraction_max 0.999
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.102
_diffrn_reflns_theta_min         2.086
_diffrn_source_current           1.4
_diffrn_source_power             0.07
_diffrn_source_voltage           50.0
_exptl_absorpt_coefficient_mu    0.652
_exptl_absorpt_correction_T_max  0.7457
_exptl_absorpt_correction_T_min  0.6760
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.0722 before and 0.0481 after correction.
The Ratio of minimum to maximum transmission is 0.9065.
The \l/2 correction factor is Not present.
;
_exptl_crystal_colour            'clear colourless'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.273
_exptl_crystal_description       irregular
_exptl_crystal_F_000             716
_exptl_crystal_size_max          0.124
_exptl_crystal_size_mid          0.113
_exptl_crystal_size_min          0.027
_refine_diff_density_max         0.317
_refine_diff_density_min         -0.504
_refine_diff_density_rms         0.058
_refine_ls_extinction_coef       0.0029(6)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2019/2 (Sheldrick 2019)'
_refine_ls_goodness_of_fit_ref   1.024
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     470
_refine_ls_number_reflns         7847
_refine_ls_number_restraints     75
_refine_ls_restrained_S_all      1.023
_refine_ls_R_factor_all          0.0609
_refine_ls_R_factor_gt           0.0403
_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/[\s^2^(Fo^2^)+(0.0356P)^2^+1.5121P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0895
_refine_ls_wR_factor_ref         0.0985
_reflns_Friedel_coverage         0.000
_reflns_number_gt                6100
_reflns_number_total             7847
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5sc08379f2.cif
_cod_data_source_block           tah25_09
_cod_database_code               1576740
_shelx_shelxl_version_number     2019/3
_shelx_estimated_absorpt_t_max   0.983
_shelx_estimated_absorpt_t_min   0.924
_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. Restrained distances
 C42-C41 \\sim C42A-C41A
 with sigma of 0.02
 C41-N6 \\sim C41A-N6A
 with sigma of 0.02
 C42-N6 \\sim C42A-N6A
 with sigma of 0.04
3. Uiso/Uaniso restraints and constraints
N6 \\sim N6A \\sim C41 \\sim C41A \\sim C42 \\sim C42A: within 2A with sigma of
0.01 and sigma for terminal atoms of 0.02 within 2A
4. Rigid body (RIGU) restrains
 N6, N6A, C41, C41A, C42, C42A
 with sigma for 1-2 distances of 0.001 and sigma for 1-3 distances of 0.001
5. Others
 Sof(N6A)=Sof(C41A)=Sof(C42A)=Sof(H42D)=Sof(H42E)=Sof(H42F)=1-FVAR(1)
 Sof(N6)=Sof(C41)=Sof(C42)=Sof(H42A)=Sof(H42B)=Sof(H42C)=FVAR(1)
6.a Secondary CH2 refined with riding coordinates:
 C12(H12A,H12B), C18(H18A,H18B)
6.b Aromatic/amide H refined with riding coordinates:
 C4(H4), C5(H5), C7(H7), C8(H8), C10(H10), C11(H11), C15(H15), C16(H16),
 C17(H17), C20(H20), C21(H21), C24(H24), C26(H26), C33(H33), C35(H35), C38(H38)
6.c Idealised Me refined as rotating group:
 C28(H28A,H28B,H28C), C29(H29A,H29B,H29C), C30(H30A,H30B,H30C), C37(H37A,H37B,
 H37C), C39(H39A,H39B,H39C), C40(H40A,H40B,H40C), C42(H42A,H42B,H42C),
 C42A(H42D,H42E,H42F)
;
_shelx_res_checksum              49512
_olex2_exptl_crystal_mounting_method 'MiTeGen 100 micron MIcroLoop'
_olex2_submission_special_instructions 'No special instructions were received'