Synthesis of planar chiral biferrocenes by iridium-catalyzed [2+2+2] cycloadition of a biferrocene-linked diyne with nitriles: asymmetric desymmetrization and kinetic resolution
Sawano, Takahiro; Murata, Kayo; Suzaki, Tomoaki; Urasawa, Kazuki; Kobayashi, Manami; Aso, Ryota; Ozasa, Kazuki; Ishikawa, Eri; Takeuchi, Ryo; Chemical Communications  (2026) –; doi:10.1039/D6CC00435K

data_7135698
_publ_section_title
;
 Synthesis of planar chiral biferrocenes by iridium-catalyzed [2+2+2]
 cycloaddition of biferrocene-linked diynes with nitriles: asymmetric
 desymmetrization and kinetic resolution.
;
_journal_issue                   33
_journal_name_full               'Chemical communications (Cambridge, England)'
_journal_page_first              8451
_journal_page_last               8455
_journal_paper_doi               10.1039/d6cc00435k
_journal_volume                  62
_journal_year                    2026
_chemical_formula_moiety         '2(C36 H26 Fe2)'
_chemical_formula_sum            'C72 H52 Fe4'
_chemical_formula_weight         1140.53
_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             2026-03-08
_audit_creation_method
;
Olex2 1.5-ac7-018
(compiled 2025.08.06 svn.rb7424aed for Rigaku Oxford Diffraction, GUI svn.r7314)
;
_audit_update_record
;
2026-03-23 deposited with the CCDC.	2026-04-02 downloaded from the CCDC.
;
_cell_angle_alpha                87.741(2)
_cell_angle_beta                 70.757(2)
_cell_angle_gamma                73.585(2)
_cell_formula_units_Z            2
_cell_length_a                   12.3172(2)
_cell_length_b                   13.1072(3)
_cell_length_c                   17.4271(3)
_cell_measurement_reflns_used    19611
_cell_measurement_temperature    99.97(11)
_cell_measurement_theta_max      79.2790
_cell_measurement_theta_min      3.9530
_cell_volume                     2543.55(9)
_computing_cell_refinement       'CrysAlisPro 1.171.44.128a (Rigaku OD, 2025)'
_computing_data_collection
'CrysAlisPro system (CCD 44.128a 64-bit (release 04-11-2025))'
_computing_data_reduction        'CrysAlisPro 1.171.44.128a (Rigaku OD, 2025)'
_computing_molecular_graphics    'Olex2 1.5-ac7-018 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5-ac7-018 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2018/3 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT 2018/2 (Sheldrick, 2018)'
_diffrn_ambient_environment      N~2~
_diffrn_ambient_temperature      99.97(11)
_diffrn_detector                 'Hybrid Pixel Array Detector'
_diffrn_detector_area_resol_mean 10.0000
_diffrn_detector_type            HyPix
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.952
_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     50.00 103.00   0.50    0.62    --  113.25-125.00 -60.00  106
  2  \w     44.00 110.00   0.50    0.62    --  113.25-125.00 -30.00  132
  3  \w     42.00  67.00   0.50    0.62    --  113.25-125.00   0.00   50
  4  \w     69.00 109.00   0.50    0.62    --  113.25-125.00  60.00   80
  5  \w     81.00 106.00   0.50    0.62    --  113.25 -99.00  90.00   50
  6  \w     42.00  77.00   0.50    0.62    --  113.25 -99.00  90.00   70
  7  \w     42.00  95.00   0.50    0.62    --  113.25 -99.00 150.00  106
  8  \w     58.00 106.00   0.50    0.62    --  113.25 -99.00  60.00   96
  9  \w     86.00 111.00   0.50    0.62    --  113.25-125.00   0.00   50
 10  \w     42.00 106.00   0.50    0.62    --  113.25 -99.00 -30.00  128
 11  \w     48.00  73.00   0.50    0.62    --  113.25 -99.00-150.00   50
 12  \w     43.00 106.00   0.50    0.62    --  113.25 -99.00-180.00  126
 13  \w     80.00 106.00   0.50    0.62    --  113.25 -99.00-150.00   52
 14  \w     35.00  89.00   0.50    0.16    --   48.61-125.00 -30.00  108
 15  \w    -21.00   4.00   0.50    0.16    --   48.61 -20.00 111.00   50
 16  \w     44.00  79.00   0.50    0.62    --  113.25 -77.00  90.00   70
 17  \w    119.00 145.00   0.50    0.62    --  113.25  38.00-150.00   52
 18  \w     91.00 138.00   0.50    0.62    --  113.25  77.00 -90.00   94
 19  \w    143.00 173.00   0.50    0.62    --  113.25  77.00 -90.00   60
 20  \w    149.00 175.00   0.50    0.62    --  113.25  38.00-150.00   52
 21  \w     61.00 106.00   0.50    0.16    --   48.61  20.00 -81.00   90
 22  \w     91.00 178.00   0.50    0.62    --  113.25  77.00   0.00  174
 23  \w    105.00 177.00   0.50    0.62    --  113.25  57.00 -30.00  144
 24  \w    109.00 149.00   0.50    0.62    --  113.25  20.00 -81.00   80
 25  \w    -59.00  18.00   0.50    0.16    --  -48.61  57.00-180.00  154
 26  \w    -21.00  27.00   0.50    0.16    --  -48.61  19.00 120.00   96
 27  \w    -22.00  21.00   0.50    0.16    --  -48.61  19.00  60.00   86
 28  \w    -23.00   9.00   0.50    0.16    --  -48.61  20.00 -81.00   64
 29  \w    -90.00 -64.00   0.50    0.62    --  -91.75  77.00 -90.00   52
 30  \w    -64.00 -38.00   0.50    0.62    --  -91.75  57.00-120.00   52
 31  \w    -66.00 -21.00   0.50    0.62    --  -91.75  57.00 -90.00   90
 32  \w    -62.00 -35.00   0.50    0.62    --  -91.75  57.00   0.00   54
 33  \w    -54.00 -19.00   0.50    0.62    --  -91.75  57.00  30.00   70
 34  \w    -65.00 -24.00   0.50    0.62    --  -91.75  57.00  90.00   82
 35  \w    -69.00 -43.00   0.50    0.62    --  -91.75 125.00   0.00   52
 36  \w    -83.00 -37.00   0.50    0.62    --  -91.75 125.00 -30.00   92
 37  \w    -90.00 -36.00   0.50    0.16    --  -48.61 -20.00 111.00  108
 38  \w   -122.00 -97.00   0.50    0.16    --  -48.61 -20.00 111.00   50
 39  \w   -157.00 -84.00   0.50    0.62    --  -91.75 -20.00 111.00  146
 40  \w   -159.00 -79.00   0.50    0.62    --  -91.75 -19.00  60.00  160
 41  \w   -160.00 -69.00   0.50    0.62    --  -91.75 -77.00-180.00  182
 42  \w   -120.00 -80.00   0.50    0.16    --  -48.61-125.00-150.00   80
 43  \w   -120.00 -95.00   0.50    0.16    --  -48.61-125.00  30.00   50
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'XtaLAB Synergy, Dualflex, HyPix'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_type
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      -0.1376562000
_diffrn_orient_matrix_UB_12      0.0401744000
_diffrn_orient_matrix_UB_13      0.0237668000
_diffrn_orient_matrix_UB_21      -0.0063539000
_diffrn_orient_matrix_UB_22      -0.1158762000
_diffrn_orient_matrix_UB_23      0.0062731000
_diffrn_orient_matrix_UB_31      -0.0110087000
_diffrn_orient_matrix_UB_32      0.0050278000
_diffrn_orient_matrix_UB_33      0.0905189000
_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  0.0316
_diffrn_reflns_av_unetI/netI     0.0307
_diffrn_reflns_Laue_measured_fraction_full 0.999
_diffrn_reflns_Laue_measured_fraction_max 0.952
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -16
_diffrn_reflns_limit_l_max       21
_diffrn_reflns_limit_l_min       -18
_diffrn_reflns_number            34367
_diffrn_reflns_point_group_measured_fraction_full 0.999
_diffrn_reflns_point_group_measured_fraction_max 0.952
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         79.554
_diffrn_reflns_theta_min         2.690
_diffrn_source                   'micro-focus sealed X-ray tube'
_diffrn_source_type              'PhotonJet (Cu) X-ray Source'
_exptl_absorpt_coefficient_mu    9.318
_exptl_absorpt_correction_T_max  0.948
_exptl_absorpt_correction_T_min  0.258
_exptl_absorpt_correction_type   gaussian
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.44.128a (Rigaku Oxford Diffraction, 2025)
Numerical absorption correction based on gaussian integration over
a multifaceted crystal model
Empirical absorption correction using spherical harmonics,
implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            'clear light orange'
_exptl_crystal_density_diffrn    1.489
_exptl_crystal_description       block
_exptl_crystal_F_000             1176
_exptl_crystal_preparation       recrystalization
_exptl_crystal_size_max          0.24
_exptl_crystal_size_mid          0.11
_exptl_crystal_size_min          0.08
_refine_diff_density_max         0.341
_refine_diff_density_min         -0.484
_refine_diff_density_rms         0.054
_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     685
_refine_ls_number_reflns         10526
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.033
_refine_ls_R_factor_all          0.0315
_refine_ls_R_factor_gt           0.0291
_refine_ls_shift/su_max          0.003
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0277P)^2^+1.7740P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0701
_refine_ls_wR_factor_ref         0.0711
_reflns_Friedel_coverage         0.000
_reflns_number_gt                9924
_reflns_number_total             10526
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d6cc00435k2.cif
_cod_data_source_block           exp_142_autored
_cod_depositor_comments
'Adding full bibliography for 7135696--7135704.cif.'
_cod_database_code               7135698
_shelx_shelxl_version_number     2018/3
_chemical_oxdiff_formula         C36H26Fe2
_chemical_oxdiff_usercomment     acetone
_shelx_estimated_absorpt_t_max   0.523
_shelx_estimated_absorpt_t_min   0.213
_diffrn_oxdiff_digest_hkl
;
43932f1d6fb5723e87a3adafb3d487f9f0b58f
;
_diffrn_oxdiff_digest_od_ed
;

;
_diffrn_oxdiff_measurement_exp_name exp_142.par
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H) groups
2.a Aromatic/amide H refined with riding coordinates:
 C005(H005), C008(H008), C00E(H00E), C00I(H00I), C00M(H00M), C00P(H00P),
 C00Q(H00Q), C00R(H00R), C00S(H00S), C00T(H00T), C00U(H00U), C00V(H00V),
 C00X(H00X), C010(H010), C011(H011), C012(H012), C014(H014), C015(H015),
 C016(H016), C017(H017), C018(H018), C019(H019), C01A(H01A), C01B(H01B),
 C01C(H01C), C01D(H01D), C01E(H01E), C01F(H01F), C01G(H01G), C01I(H01I),
 C01J(H01J), C01K(H01K), C01L(H01L), C01M(H01M), C01N(H01N), C01O(H01O),
 C01P(H01P), C01Q(H01Q), C01R(H01R), C01S(H01S), C01T(H01T), C01U(H01U),
 C01V(H01V), C01W(H01W), C01X(H01X), C01Y(H01Y), C01Z(H01Z), C020(H020),
 C021(H021), C022(H022), C023(H023), C024(H024)
;
_shelx_res_checksum              22302
_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 1.316
_oxdiff_exptl_absorpt_empirical_full_min 0.769