Alkali Metal Cation Effects for Rapid C–H Activation by Iron(0) Complexes
Hidalgo, Nereida; Southwell, Kendal W.; Donnelly, Ryan; Mercado, Brandon Q.; Krajewski, Sebastian M.; Wang, Xiaoping; Holland, Patrick L.; Chemical Science  (2026) –; doi:10.1039/D6SC01470D

data_1576992
_publ_section_title
;
 Alkali metal cation effects for rapid C-H activation by iron(0)
 complexes.
;
_journal_issue                   20
_journal_name_full               'Chemical science'
_journal_page_first              10061
_journal_page_last               10066
_journal_paper_doi               10.1039/d6sc01470d
_journal_volume                  17
_journal_year                    2026
_chemical_absolute_configuration rm
_chemical_formula_moiety
'0.5(C43 H65 Fe K N2 O6), 0.5(C43 H69 Fe K N2 O6), 0.5(C7 H8)'
_chemical_formula_sum            'C46.5 H71 Fe K N2 O6'
_chemical_formula_weight         849.00
_space_group_crystal_system      monoclinic
_space_group_IT_number           4
_space_group_name_Hall           'P 2yb'
_space_group_name_H-M_alt        'P 1 21 1'
_atom_sites_solution_hydrogens   mixed
_atom_sites_solution_primary     dual
_audit_creation_date             2025-10-24
_audit_creation_method
;
Olex2 1.5
(compiled 2025.07.13 svn.rb7424aed for OlexSys, GUI svn.r7314)
;
_audit_update_record
;
2025-12-16 deposited with the CCDC.	2026-03-31 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 97.665(2)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   12.5751(3)
_cell_length_b                   17.5962(6)
_cell_length_c                   21.7879(5)
_cell_measurement_reflns_used    8147
_cell_measurement_temperature    100
_cell_measurement_theta_max      68.1780
_cell_measurement_theta_min      3.2270
_cell_volume                     4778.0(2)
_computing_cell_refinement       'CrysAlisPro 1.171.44.85 (Rigaku OD, 2024)'
_computing_data_collection
'CrysAlisPro system (CCD 43.92a 64-bit (release 05-10-2023))'
_computing_data_reduction        'CrysAlisPro 1.171.44.85 (Rigaku OD, 2024)'
_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_temperature      100
_diffrn_detector                 'CCD plate'
_diffrn_measured_fraction_theta_full 0.985
_diffrn_measured_fraction_theta_max 0.974
_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    -19.00   6.00   1.00    4.50    --    5.00  45.00 126.00   25
  2  \w   -178.00 -57.00   1.00   18.03    --  -90.00  45.00 126.00  121
  3  \w    -84.00  74.00   1.00    4.50    --    0.00   0.00-180.00  158
  4  \w   -176.00 -85.00   1.00   18.03    --  -90.00  28.00  90.00   91
  5  \w    -50.00  -1.00   1.00   18.03    --  -90.00  28.00  90.00   49
  6  \w   -150.00 -50.00   1.00   18.03    --  -90.00  46.00 -90.00  100
  7  \w   -104.00 -77.00   1.00   18.03    --  -90.00  46.00  30.00   27
  8  \w   -109.00  -6.00   1.00   18.03    --  -90.00   0.00-180.00  103
  9  \w   -153.00-128.00   1.00   18.03    --  -90.00  37.00  60.00   25
 10  \w   -176.00 -20.00   1.00   18.03    --  -90.00  28.00-120.00  156
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'XtaLAB AFC11 (RCD3): quarter-chi single'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_type
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      -0.0822393000
_diffrn_orient_matrix_UB_12      -0.0498389000
_diffrn_orient_matrix_UB_13      0.0279169000
_diffrn_orient_matrix_UB_21      0.0915915000
_diffrn_orient_matrix_UB_22      -0.0371346000
_diffrn_orient_matrix_UB_23      0.0438841000
_diffrn_orient_matrix_UB_31      -0.0111665000
_diffrn_orient_matrix_UB_32      0.0616482000
_diffrn_orient_matrix_UB_33      0.0488617000
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.1224
_diffrn_reflns_av_unetI/netI     0.1410
_diffrn_reflns_Laue_measured_fraction_full 0.985
_diffrn_reflns_Laue_measured_fraction_max 0.974
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -13
_diffrn_reflns_limit_k_max       21
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -22
_diffrn_reflns_number            28002
_diffrn_reflns_point_group_measured_fraction_full 0.810
_diffrn_reflns_point_group_measured_fraction_max 0.799
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         68.640
_diffrn_reflns_theta_min         2.046
_diffrn_source                   'Rotating-anode X-ray tube'
_diffrn_source_type              'Rigaku (Cu) X-ray Source'
_exptl_absorpt_coefficient_mu    3.667
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.25683
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.44.85 (Rigaku Oxford Diffraction, 2024)
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            red
_exptl_crystal_colour_primary    red
_exptl_crystal_density_diffrn    1.180
_exptl_crystal_description       block
_exptl_crystal_F_000             1828
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.2
_refine_diff_density_max         0.673
_refine_diff_density_min         -0.332
_refine_diff_density_rms         0.097
_refine_ls_abs_structure_details
;
 Flack x determined using 1872 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   -0.014(10)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.081
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     1039
_refine_ls_number_reflns         14086
_refine_ls_number_restraints     1391
_refine_ls_restrained_S_all      1.043
_refine_ls_R_factor_all          0.1917
_refine_ls_R_factor_gt           0.1097
_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^)+(0.0987P)^2^+14.8129P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2408
_refine_ls_wR_factor_ref         0.2863
_reflns_Friedel_coverage         0.584
_reflns_Friedel_fraction_full    0.623
_reflns_Friedel_fraction_max     0.611
_reflns_number_gt                7563
_reflns_number_total             14086
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d6sc01470d2.cif
_cod_data_source_block           007b-24050
_cod_depositor_comments
'Adding full bibliography for 1576987--1576994.cif.'
_cod_original_formula_sum        'C46.50 H71 Fe K N2 O6'
_cod_database_code               1576992
_shelx_shelxl_version_number     2019/3
_chemical_oxdiff_formula         'C48 H72 Fe K N2 O6'
_shelx_estimated_absorpt_t_max   0.528
_shelx_estimated_absorpt_t_min   0.528
_diffrn_oxdiff_digest_od_ed
;

;
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups, All C(H,H) groups, All C(H,H,H,H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2. Restrained distances
 C39-C38 \\sim C40-C41 \\sim C42-C43 \\sim C33-C32 \\sim C34-C35 \\sim C37-C36
\\sim C33B-C32B \\sim C42B-
 C43B \\sim C41B-C40B \\sim C38B-C39B \\sim C37B-C36B \\sim C35B-C34B
 with sigma of 0.02
 O6-C43 \\sim O5-C42 \\sim O4-C40 \\sim O3-C38 \\sim O2-C36 \\sim O3-C37 \\sim
O1-C34 \\sim O1-C33 \\sim O6-
 C32 \\sim O2-C35 \\sim O1B-C34B \\sim O1B-C33B \\sim O6B-C32B \\sim O6B-C43B
\\sim O5B-C42B \\sim O5B-C41B
 \\sim O4B-C40B \\sim O4B-C39B \\sim O3B-C38B \\sim O3B-C37B \\sim O2B-C36B
\\sim O2B-C35B
 with sigma of 0.02
 H7BB-H7BA \\sim H6BB-H6BA
 with sigma of 0.02
 C6B-H6BB \\sim C6B-H6BA \\sim C7B-H7BA \\sim C7B-H7BB
 with sigma of 0.02
3. Uiso/Uaniso restraints and constraints
C46 \\sim H46 \\sim C45 \\sim H45 \\sim C44 \\sim C49 \\sim H49 \\sim C48 \\sim
H48 \\sim C47 \\sim H47 \\sim C50 \\sim H50A \\sim H50B \\sim H50C: within 2A
with sigma of 0.04 and sigma for terminal atoms of 0.08 within 2A
C1 \\sim C2 \\sim C3 \\sim C4 \\sim C5 \\sim C6 \\sim C7 \\sim C8 \\sim C9
\\sim C10 \\sim C11 \\sim C12 \\sim C13 \\sim C14 \\sim C15 \\sim C16 \\sim C17
\\sim C18 \\sim C19 \\sim C20 \\sim C21 \\sim C22 \\sim C23 \\sim C24 \\sim C25
\\sim C26 \\sim C27 \\sim C28 \\sim C29 \\sim C30 \\sim C31 \\sim C32 \\sim C34
\\sim C35 \\sim C36 \\sim C37 \\sim C38 \\sim C39 \\sim C40 \\sim C41 \\sim C42
\\sim C43 \\sim C1B \\sim C2B \\sim C3B \\sim C4B \\sim C5B \\sim C6B \\sim C7B
\\sim C8B \\sim C9B \\sim C10B \\sim C11B \\sim C12B \\sim C13B \\sim C14B
\\sim C15B \\sim C16B \\sim C17B \\sim C18B \\sim C19B \\sim C20B \\sim C21B
\\sim C22B \\sim C23B \\sim C24B \\sim C25B \\sim C26B \\sim C27B \\sim C28B
\\sim C29B \\sim C30B \\sim C31B \\sim C32B \\sim C33B \\sim C34B \\sim C35B
\\sim C36B \\sim C37B \\sim C38B \\sim C39B \\sim C40B \\sim C41B \\sim C42B
\\sim C43B \\sim C46 \\sim C45 \\sim C44 \\sim C49 \\sim C48 \\sim C47 \\sim
C50: within 2A with sigma of 0.04 and sigma for terminal atoms of 0.08 within 2A
Uanis(C7B) \\sim Ueq: with sigma of 0.005 and sigma for terminal atoms of 0.01
Uanis(O1) \\sim Ueq, Uanis(O2) \\sim Ueq, Uanis(O3) \\sim Ueq, Uanis(O4) \\sim
Ueq, Uanis(O5) \\sim Ueq, Uanis(O6) \\sim Ueq, Uanis(C32) \\sim Ueq, Uanis(C33)
\\sim Ueq, Uanis(C34) \\sim Ueq, Uanis(C35) \\sim Ueq, Uanis(C36) \\sim Ueq,
Uanis(C37) \\sim Ueq, Uanis(C38) \\sim Ueq, Uanis(C39) \\sim Ueq, Uanis(C40)
\\sim Ueq, Uanis(C41) \\sim Ueq, Uanis(C42) \\sim Ueq, Uanis(C43) \\sim Ueq:
with sigma of 0.016 and sigma for terminal atoms of 0.032
4. Rigid body (RIGU) restrains
 C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17,
 C18, C19, C20, C21, C22, C23, C24, C25, C26, C27, C28, C29, C30, C31, C32, C33,
  C34, C35, C36, C37, C38, C39, C40, C41, C42, C43, C1B, C2B, C3B, C4B, C5B,
 C6B, C7B, C8B, C9B, C10B, C11B, C12B, C13B, C14B, C15B, C16B, C17B, C18B, C19B,
  C20B, C21B, C22B, C23B, C24B, C25B, C26B, C27B, C28B, C29B, C30B, C31B, C32B,
 C33B, C34B, C35B, C36B, C37B, C38B, C39B, C40B, C41B, C42B, C43B, C46, C45,
 C44, C49, C48, C47, C50
 with sigma for 1-2 distances of 0.004 and sigma for 1-3 distances of 0.004
5.a Ternary CH refined with riding coordinates:
 C14(H14), C17(H17), C26(H26), C29(H29), C14B(H14B), C17B(H17B), C26B(H26B),
 C29B(H29B)
5.b Secondary CH2 refined with riding coordinates:
 C32(H32C,H32D), C33(H33C,H33D), C34(H34C,H34D), C35(H35C,H35D), C36(H36C,
 H36D), C37(H37C,H37D), C38(H38C,H38D), C39(H39C,H39D), C40(H40C,H40D),
 C41(H41C,H41D), C42(H42C,H42D), C43(H43C,H43D), C32B(H32A,H32B), C33B(H33A,
 H33B), C34B(H34A,H34B), C35B(H35A,H35B), C36B(H36A,H36B), C37B(H37A,H37B),
 C38B(H38A,H38B), C39B(H39A,H39B), C40B(H40A,H40B), C41B(H41A,H41B), C42B(H42A,
 H42B), C43B(H43A,H43B)
5.c Aromatic/amide H refined with riding coordinates:
 C2(H2), C10(H10), C11(H11), C12(H12), C22(H22), C23(H23), C24(H24), C2B(H2B),
 C10B(H10B), C11B(H11B), C12B(H12B), C22B(H22B), C23B(H23B), C24B(H24B),
 C46(H46), C45(H45), C49(H49), C48(H48), C47(H47)
5.d Fitted hexagon refined as free rotating group:
 C46(C45,C44,C49,C48,C47)
5.e Idealised Me refined as rotating group:
 C4(H4A,H4B,H4C), C5(H5A,H5B,H5C), C15(H15D,H15E,H15F), C16(H16D,H16E,H16F),
 C18(H18D,H18E,H18F), C19(H19D,H19E,H19F), C27(H27D,H27E,H27F), C28(H28D,H28E,
 H28F), C30(H30D,H30E,H30F), C31(H31D,H31E,H31F), C4B(H4BA,H4BB,H4BC), C5B(H5BA,
 H5BB,H5BC), C15B(H15A,H15B,H15C), C16B(H16A,H16B,H16C), C18B(H18A,H18B,H18C),
 C19B(H19A,H19B,H19C), C27B(H27A,H27B,H27C), C28B(H28A,H28B,H28C), C30B(H30A,
 H30B,H30C), C31B(H31A,H31B,H31C), C50(H50A,H50B,H50C)
;
_shelx_res_checksum              77872
_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 5.061
_oxdiff_exptl_absorpt_empirical_full_min 0.360