The “pogo stick” complex [FeCp*{N(SiMe3)2}]: spin state properties, adduct formation with Lewis bases, and reactivity towards weakly Brønsted acidic protonated NHCs
Zinke, Julian; Bruhn, Clemens; Demeshko, Serhiy; Siemeling, Ulrich; Dalton Transactions 54 (2025) 5812–5828; doi:10.1039/D5DT00300H

data_7718193
_publ_section_title
;
 The &#x201C;pogo stick&#x201D; complex [FeCp*{N(SiMe3)2}]: spin state
 properties, adduct formation with Lewis bases, and reactivity towards
 weakly Br\/onsted acidic protonated NHCs
;
_journal_issue                   14
_journal_name_full               'Dalton Transactions'
_journal_page_first              5812
_journal_page_last               5828
_journal_paper_doi               10.1039/D5DT00300H
_journal_volume                  54
_journal_year                    2025
_chemical_formula_moiety         'C10 H15 Fe I2, C28 H35 Fe N4, 1.5(C6 H6)'
_chemical_formula_sum            'C44 H56 Fe2 I2 N4'
_chemical_formula_weight         1006.42
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2ybc'
_space_group_name_H-M_alt        'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     dual
_audit_creation_date             2023-03-03
_audit_creation_method
;
Olex2 1.5
(compiled 2023.02.24 svn.rf166f9f3 for OlexSys, GUI svn.r6725)
;
_audit_update_record
;
2025-02-05 deposited with the CCDC.	2025-03-03 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 115.625(11)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   12.595(2)
_cell_length_b                   27.760(2)
_cell_length_c                   14.5083(14)
_cell_measurement_reflns_used    32557
_cell_measurement_temperature    100
_cell_measurement_theta_max      26.28
_cell_measurement_theta_min      1.72
_cell_volume                     4573.7(10)
_computing_cell_refinement
;
X-Area Recipe 1.37.0.0 (STOE, 2021)
;
_computing_data_collection
;
X-Area WinXpose 2.0.22.0 (STOE, 2016)
;
_computing_data_reduction
;
X-Area Integrate 2.5.1.0 (STOE, 2021)
X-Area LANA 2.6.2.0 (STOE, 2021)
;
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material
;
STOE & Cie GmbH, X-Area, software package for collecting single-crystal or
multi-domain crystal data on STOE area-detector diffractometers, for image 
processing, for the correction and scaling of reflection intensities and 
for outlier rejection, version 2.0, Darmstadt 2021
;
_computing_structure_refinement  'SHELXL 2014/7 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT  (Sheldrick, 2015)'
_diffrn_ambient_temperature      100
_diffrn_detector                 'image plate (34 cm diameter)'
_diffrn_detector_area_resol_mean 6.67
_diffrn_detector_type            'STOE Imaging Plate'
_diffrn_measured_fraction_theta_full 0.995
_diffrn_measured_fraction_theta_max 0.981
_diffrn_measurement_details
;
 260 frames, detector distance = 130 mm
;
_diffrn_measurement_device       '2-circle diffractometer'
_diffrn_measurement_device_type  'STOE IPDS II'
_diffrn_measurement_method       'rotation method, \w scans'
_diffrn_radiation_collimation    '1.2, 0.6 mm diameter, multiple pinhole'
_diffrn_radiation_monochromator  'plane graphite'
_diffrn_radiation_polarisn_norm  270
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0410
_diffrn_reflns_av_unetI/netI     0.0411
_diffrn_reflns_Laue_measured_fraction_full 0.995
_diffrn_reflns_Laue_measured_fraction_max 0.981
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       34
_diffrn_reflns_limit_k_min       -29
_diffrn_reflns_limit_l_max       15
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            18314
_diffrn_reflns_point_group_measured_fraction_full 0.995
_diffrn_reflns_point_group_measured_fraction_max 0.981
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         25.873
_diffrn_reflns_theta_min         1.721
_diffrn_source                   'Genix Mo HF'
_diffrn_source_current           1.00
_diffrn_source_power             0.050
_diffrn_source_voltage           50
_exptl_absorpt_coefficient_mu    2.017
_exptl_absorpt_correction_T_max  0.9227
_exptl_absorpt_correction_T_min  0.6826
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
STOE X-Red32, absorption correction by Gaussian integration, analogous to
P. Coppens, "The Evaluation of Absorption and Extinction in Single-Crystal
Structure Analysis", published in: F. R. Ahmed (Editor), "Crystallographic
Computing", Munksgaard, Copenhagen (1970), 255 - 270. Afterwards scaling of
reflection intensities was performed within STOE LANA. J. Koziskova, F. Hahn,
J. Richter, J. Kozisek, Acta Chimica Slovaca, vol. 9, no. 2, 2016, pp. 136-140.
;
_exptl_crystal_colour            yellow
_exptl_crystal_colour_primary    yellow
_exptl_crystal_density_diffrn    1.462
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       plate
_exptl_crystal_F_000             2024
_exptl_crystal_size_max          0.19
_exptl_crystal_size_mid          0.107
_exptl_crystal_size_min          0.04
_refine_diff_density_max         0.832
_refine_diff_density_min         -1.309
_refine_diff_density_rms         0.134
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.022
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     483
_refine_ls_number_reflns         8713
_refine_ls_number_restraints     75
_refine_ls_restrained_S_all      1.036
_refine_ls_R_factor_all          0.0750
_refine_ls_R_factor_gt           0.0531
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0825P)^2^+12.2507P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1344
_refine_ls_wR_factor_ref         0.1527
_reflns_Friedel_coverage         0.000
_reflns_number_gt                6448
_reflns_number_total             8713
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5dt00300h2.cif
_cod_data_source_block           i3412
_cod_depositor_comments
'Adding full bibliography for 7718189--7718202.cif.'
_cod_database_code               7718193
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_max   0.924
_shelx_estimated_absorpt_t_min   0.701
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2. Rigid body (RIGU) restrains
 C27, C28, C24, C25, C26, C21, C22, C23, C19, C20
 with sigma for 1-2 distances of 0.004 and sigma for 1-3 distances of 0.004
3.a Aromatic/amide H refined with riding coordinates:
 C4(H4), C5(H5), C6(H6), C7(H7), C13(H13), C14(H14), C15(H15), C16(H16),
 C39(H39), C40(H40), C41(H41), C42(H42), C43(H43), C44(H44)
3.b Idealised Me refined as rotating group:
 C8(H8A,H8B,H8C), C9(H9A,H9B,H9C), C17(H17A,H17B,H17C), C18(H18A,H18B,H18C),
 C24(H24A,H24B,H24C), C25(H25A,H25B,H25C), C26(H26A,H26B,H26C), C27(H27A,H27B,
 H27C), C28(H28A,H28B,H28C), C34(H34A,H34B,H34C), C35(H35A,H35B,H35C), C36(H36A,
 H36B,H36C), C37(H37A,H37B,H37C), C38(H38A,H38B,H38C)
;
_smtbx_masks_void_probe_radius   1.2
_smtbx_masks_void_truncation_radius 1.2
_shelx_res_checksum              36365
_shelx_hkl_checksum              76213
_shelx_fab_checksum              81708
_olex2_submission_special_instructions 'No special instructions were received'
_stoe_detector_distance          '130.0 mm'
_stoe_detector_pixelsize_x       '0.150 mm'
_stoe_detector_pixelsize_y       '0.150 mm'
_stoe_detector_size_x            '34.0 cm'
_stoe_detector_size_y            '34.0 cm'
_stoe_evaluation_integration_a   12.0
_stoe_evaluation_integration_b   0.0
_stoe_evaluation_integration_ems 0.012
_stoe_evaluation_lana_bis_l_even_max -
_stoe_evaluation_lana_bis_l_odd_max -
_stoe_evaluation_lana_bos_l_even_max -
_stoe_evaluation_lana_bos_l_odd_max -
_stoe_evaluation_lana_completeness 97.4
_stoe_evaluation_lana_dxs_max_order 1
_stoe_evaluation_lana_dys_max_order 1
_stoe_evaluation_lana_fs_max_order 3
_stoe_evaluation_lana_max_2theta_available 51.9
_stoe_evaluation_lana_max_2theta_desired 51.9
_stoe_evaluation_lana_mean_redundancy 2.1
_stoe_evaluation_lana_number_refls_after_or 18332
_stoe_evaluation_lana_number_refls_outliers 4437
_stoe_evaluation_lana_number_refls_total 22769
_stoe_evaluation_lana_number_refls_unique 8723
_stoe_evaluation_lana_number_refls_written 18332
_stoe_evaluation_lana_or_c1      0.035
_stoe_evaluation_lana_or_c2      0
_stoe_evaluation_lana_or_c3      0
_stoe_evaluation_lana_or_c4      0.7
_stoe_evaluation_lana_point_group 2/m
_stoe_evaluation_lana_table
;
2Theta           5.3   10.9   16.5   22.1   27.7   33.3   38.9   44.5   50.1
<Resolution>    6.63   3.59   2.44   1.84   1.47   1.24   1.06   0.94   0.85
N(total)          97    390    855   1572   2378   3247   4371   5370   4489
<Redundancy>     2.1    2.1    2.1    2.1    2.1    2.1    2.1    2.1    2.1
Complet. [%%]    97.1   97.9   99.4  100.0   99.5   99.2   99.5   99.8   90.4
<I/sigma>      484.0  288.8  184.2  121.9   65.6   40.9   21.5    9.7    3.8
R(int)         0.074  0.043  0.023  0.031  0.029  0.034  0.043  0.077  0.184
;
_stoe_measurement_identifier     i3412
_stoe_measurement_max_exposure_per_frame '480.0 s'
_stoe_measurement_mean_exposure_per_frame '480.0 s'
_stoe_measurement_min_exposure_per_frame '480.0 s'
_stoe_measurement_total_exposure_time '34.7 h'
_stoe_measurement_total_frame_number 260
_stoe_measurement_total_run_number 1
_stoe_measurement_tube_power     '50.0 W'