Initiating olefin metathesis: alkylidenes from molecular Mo(iv)-oxo species, olefins and base-promoted proton transfer
Nater, Darryl F.; de Zwart, Felix J.; Kaeffer, Nicolas; Copéret, Christophe; Chemical Science  (2025) –; doi:10.1039/D5SC06662J

data_1576236
_publ_section_title
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 Initiating olefin metathesis: alkylidenes from molecular Mo(iv)-oxo
 species, olefins and base-promoted proton transfer
;
_journal_name_full               'Chemical Science'
_journal_paper_doi               10.1039/D5SC06662J
_journal_year                    2025
_chemical_formula_moiety         'C23.1 H24.1 F27.9 Mo2 O8 Si0.9'
_chemical_formula_sum            'C23.1 H24.1 F27.9 Mo2 O8 Si0.9'
_chemical_formula_weight         1176.98
_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             2022-03-30
_audit_creation_method
;
Olex2 1.5
(compiled 2021.12.09 svn.r5202d8cf for OlexSys, GUI svn.r6439)
;
_audit_update_record
;
2025-08-25 deposited with the CCDC.	2025-10-27 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 110.743(4)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   10.8082(4)
_cell_length_b                   17.7991(5)
_cell_length_c                   10.1192(4)
_cell_measurement_reflns_used    39460
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      46.4360
_cell_measurement_theta_min      2.1660
_cell_volume                     1820.51(12)
_computing_molecular_graphics    'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 1.5 (Dolomanov et al., 2009)'
_computing_structure_refinement  'SHELXL 2018/3 (Sheldrick, 2015)'
_computing_structure_solution    'SHELXT  (Sheldrick, 2015)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.994
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device       'abstract diffractometer'
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0912
_diffrn_reflns_av_unetI/netI     0.0298
_diffrn_reflns_Laue_measured_fraction_full 0.994
_diffrn_reflns_Laue_measured_fraction_max 0.996
_diffrn_reflns_limit_h_max       15
_diffrn_reflns_limit_h_min       -15
_diffrn_reflns_limit_k_max       25
_diffrn_reflns_limit_k_min       -24
_diffrn_reflns_limit_l_max       14
_diffrn_reflns_limit_l_min       -14
_diffrn_reflns_number            67950
_diffrn_reflns_point_group_measured_fraction_full 0.994
_diffrn_reflns_point_group_measured_fraction_max 0.996
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         29.999
_diffrn_reflns_theta_min         2.317
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.907
_exptl_absorpt_correction_T_max  0.7482
_exptl_absorpt_correction_T_min  0.6038
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
SADABS-2016/2 (Bruker,2016/2) was used for absorption correction.
wR2(int) was 0.0749 before and 0.0564 after correction.
The Ratio of minimum to maximum transmission is 0.8070.
The \l/2 correction factor is Not present.
;
_exptl_crystal_colour            'clear reddish brown'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_modifier   reddish
_exptl_crystal_colour_primary    brown
_exptl_crystal_density_diffrn    2.147
_exptl_crystal_description       plate
_exptl_crystal_F_000             1149
_exptl_crystal_size_max          0.2
_exptl_crystal_size_mid          0.2
_exptl_crystal_size_min          0.1
_refine_diff_density_max         3.225
_refine_diff_density_min         -1.159
_refine_diff_density_rms         0.217
_refine_ls_extinction_coef       0.045(5)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2018/3 (Sheldrick 2018)'
_refine_ls_goodness_of_fit_ref   1.051
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     368
_refine_ls_number_reflns         5288
_refine_ls_number_restraints     484
_refine_ls_restrained_S_all      1.090
_refine_ls_R_factor_all          0.0880
_refine_ls_R_factor_gt           0.0839
_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^)+(0.1443P)^2^+10.0962P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.2282
_refine_ls_wR_factor_ref         0.2358
_reflns_Friedel_coverage         0.000
_reflns_number_gt                4948
_reflns_number_total             5288
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            d5sc06662j2.cif
_cod_data_source_block           dn338
_cod_original_cell_volume        1820.50(12)
_cod_original_formula_sum        'C23.10 H24.10 F27.90 Mo2 O8 Si0.90'
_cod_database_code               1576236
_shelx_shelxl_version_number     2018/3
_shelx_estimated_absorpt_t_max   0.915
_shelx_estimated_absorpt_t_min   0.839
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.2 times of:
  All C(H,H) groups
 At 1.5 times of:
  All C(H,H,H) groups
2. Restrained distances
 O3-C5A
 1.42 with sigma of 0.004
 O3-Si5
 1.64 with sigma of 0.004
 C9-C10A = C9-C11A = C9-C12A = C9-C12B = C5A-C6A = C5A-C7A = C5A-C8A
 1.52 with sigma of 0.01
 C5A-C6A \\sim C5A-C7A \\sim C5A-C8A
 with sigma of 0.02
 C7A-F4A \\sim C7A-F5A
 with sigma of 0.02
 F16-F17 \\sim F16-F18A \\sim F17-F18A \\sim F17-F18B \\sim F18B-F16
 with sigma of 0.02
 F10-F11 \\sim F10-F12A \\sim F11-F12A \\sim F10-F12B \\sim F11-F12B
 with sigma of 0.02
 F13-F14 \\sim F13-F15A \\sim F14-F15A \\sim F13-F15B \\sim F14-F15B
 with sigma of 0.02
 C11A-F13 \\sim C11A-F14 \\sim C11A-F15A \\sim C11B-F13 \\sim C11B-F14 \\sim
C11B-F15B
 with sigma of 0.02
 C12A-F16 \\sim C12A-F17 \\sim C12A-F18A \\sim C12B-F16 \\sim C12B-F17 \\sim
C12B-F18B
 with sigma of 0.02
 C10A-F10 \\sim C10A-F11 \\sim C10A-F12A \\sim C10B-F10 \\sim C10B-F11 \\sim
C10B-F12B
 with sigma of 0.02
3. Uiso/Uaniso restraints and constraints
Uanis(C12B) = Uanis(C12A)
Uanis(F12B) = Uanis(F10)
Uanis(F15B) = Uanis(F14)
Uanis(C5A) = Uanis(C6A)
Uanis(C9) = Uanis(O4)
Uanis(C7B) = Uanis(C6B)
Uanis(C7A) = Uanis(C6A)
4. Rigid body (RIGU) restrains
 All non-hydrogen atoms
 with sigma for 1-2 distances of 0.004 and sigma for 1-3 distances of 0.004
5. Others
 Fixed Sof: Si5(0.45) C6B(0.45) H6BA(0.45) H6BB(0.45) H6BC(0.45) C7B(0.45)
 H7BA(0.45) H7BB(0.45) H7BC(0.45) C8B(0.45) H8BA(0.45) H8BB(0.45) H8BC(0.45)
 C5A(0.55) C6A(0.55) C7A(0.55) C8A(0.55) F1A(0.55) F2A(0.55) F3A(0.55)
 F4A(0.55) F5A(0.55) F6A(0.55) F7A(0.55) F8A(0.55) F9A(0.55) C10A(0.59)
 C11A(0.59) C12A(0.59) F12A(0.59) F15A(0.59) F18A(0.59) C10B(0.41) C11B(0.41)
 C12B(0.41) F12B(0.41) F15B(0.41) F18B(0.41)
6.a Secondary CH2 refined with riding coordinates:
 C1(H1A,H1B), C2(H2A,H2B), C3(H3A,H3B), C4(H4A,H4B)
6.b Idealised Me refined as rotating group:
 C6B(H6BA,H6BB,H6BC), C7B(H7BA,H7BB,H7BC), C8B(H8BA,H8BB,H8BC)
;
_shelx_res_checksum              78601
_olex2_submission_special_instructions 'No special instructions were received'