Uranium(iv) cyclobutadienyl sandwich compounds: synthesis, structure and chemical bonding.
Tsoureas, Nikolaos; Mansikkamäki, Akseli; Layfield, Richard A.; Chemical communications (Cambridge, England) 56 (2020) 944–947; doi:10.1039/c9cc09018e

data_7125702
_publ_section_title
;
 Uranium(iv) cyclobutadienyl sandwich compounds: synthesis, structure and
 chemical bonding.
;
_journal_issue                   6
_journal_name_full
'Chemical communications (Cambridge, England)'
_journal_page_first              944
_journal_page_last               947
_journal_paper_doi               10.1039/c9cc09018e
_journal_volume                  56
_journal_year                    2020
_chemical_formula_moiety         'C32 H76 B Si8 U, C20 H47.7 Na O4'
_chemical_formula_sum            'C52 H123.7 B Na O4 Si8 U'
_chemical_formula_weight         1309.75
_chemical_name_systematic        3
_chemical_properties_physical
Air-sensitive,Moisture-sensitive,Oxygen-sensitive
_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   mixed
_atom_sites_solution_primary     direct
_audit_creation_date             2019-09-21
_audit_creation_method
;
Olex2 1.2
(compiled 2018.05.29 svn.r3508 for OlexSys, GUI svn.r5506)
;
_audit_update_record
;
2019-12-10 deposited with the CCDC.	2019-12-11 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 97.5838(11)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   13.20381(14)
_cell_length_b                   26.1179(3)
_cell_length_c                   20.8685(2)
_cell_measurement_reflns_used    9773
_cell_measurement_temperature    100.15
_cell_measurement_theta_max      70.8120
_cell_measurement_theta_min      3.7800
_cell_volume                     7133.67(13)
_computing_cell_refinement       'CrysAlisPro 1.171.39.46 (Rigaku OD, 2018)'
_computing_data_collection       'CrysAlisPro 1.171.39.46 (Rigaku OD, 2018)'
_computing_data_reduction        'CrysAlisPro 1.171.39.46 (Rigaku OD, 2018)'
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'ShelXL (Sheldrick, 2015)'
_computing_structure_solution    'ShelXS (Sheldrick, 2008)'
_diffrn_ambient_temperature      100.15
_diffrn_detector                 'CCD plate'
_diffrn_detector_area_resol_mean 16.1033
_diffrn_detector_type            Eos
_diffrn_measured_fraction_theta_full 0.996
_diffrn_measured_fraction_theta_max 0.996
_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    -49.00  32.00   1.00    8.00    --  -36.88  38.00 150.00   81
  2  \w   -106.00 -54.00   1.00    8.00    --  -36.88 178.00 120.00   52
  3  \w     26.00 105.00   1.00    8.00    --   36.88  38.00  60.00   79
  4  \w     21.00  81.00   1.00    8.00    --   36.88  57.00 -30.00   60
  5  \w     76.00 174.00   1.00   15.00    --  107.00  15.00 150.00   98
  6  \w     91.00 175.00   1.00   15.00    --  107.00  45.00  30.00   84
  7  \w     39.00 119.00   1.00   15.00    --  107.00 -45.00  60.00   80
  8  \w     37.00 128.00   1.00   15.00    --  107.00 -30.00-150.00   91
  9  \w     37.00  84.00   1.00   15.00    --  107.00 -30.00   0.00   47
;
_diffrn_measurement_device       'four-circle diffractometer'
_diffrn_measurement_device_type  'Xcalibur, Eos, Gemini ultra'
_diffrn_measurement_method       '\w scans'
_diffrn_orient_matrix_type
'CrysAlisPro convention (1999,Acta A55,543-557)'
_diffrn_orient_matrix_UB_11      0.1024419000
_diffrn_orient_matrix_UB_12      -0.0160583000
_diffrn_orient_matrix_UB_13      0.0388663000
_diffrn_orient_matrix_UB_21      0.0573585000
_diffrn_orient_matrix_UB_22      0.0351928000
_diffrn_orient_matrix_UB_23      -0.0422391000
_diffrn_orient_matrix_UB_31      -0.0084314000
_diffrn_orient_matrix_UB_32      0.0445430000
_diffrn_orient_matrix_UB_33      0.0474303000
_diffrn_radiation_monochromator  mirror
_diffrn_radiation_probe          x-ray
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.0332
_diffrn_reflns_av_unetI/netI     0.0519
_diffrn_reflns_Laue_measured_fraction_full 0.996
_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       31
_diffrn_reflns_limit_k_min       -28
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            21848
_diffrn_reflns_point_group_measured_fraction_full 0.996
_diffrn_reflns_point_group_measured_fraction_max 0.996
_diffrn_reflns_theta_full        67.070
_diffrn_reflns_theta_max         67.070
_diffrn_reflns_theta_min         3.377
_diffrn_source                   'fine-focus sealed X-ray tube'
_diffrn_source_type              'Enhance Ultra (Cu) X-ray Source'
_exptl_absorpt_coefficient_mu    8.013
_exptl_absorpt_correction_T_max  1.00000
_exptl_absorpt_correction_T_min  0.70149
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.39.46 (Rigaku Oxford Diffraction, 2018)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            'dark brown'
_exptl_crystal_density_diffrn    1.220
_exptl_crystal_description       block
_exptl_crystal_F_000             2751
_exptl_crystal_recrystallization_method
'Re-crystallisation from solvent: tBuOMe with a few drops of THF'
_exptl_crystal_size_max          0.15
_exptl_crystal_size_mid          0.1
_exptl_crystal_size_min          0.08
_refine_diff_density_max         3.357
_refine_diff_density_min         -2.520
_refine_diff_density_rms         0.116
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.032
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     720
_refine_ls_number_reflns         12686
_refine_ls_number_restraints     105
_refine_ls_restrained_S_all      1.042
_refine_ls_R_factor_all          0.0543
_refine_ls_R_factor_gt           0.0437
_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^)+(0.0510P)^2^+18.0368P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1052
_refine_ls_wR_factor_ref         0.1123
_reflns_Friedel_coverage         0.000
_reflns_number_gt                10641
_reflns_number_total             12686
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c9cc09018e2.cif
_cod_data_source_block           3
_cod_depositor_comments
'Adding full bibliography for 7125700--7125702.cif.'
_cod_original_cell_volume        7133.65(14)
_cod_original_formula_sum        'C52 H123.70 B Na O4 Si8 U'
_cod_database_code               7125702
_shelx_shelxl_version_number     2014/7
_chemical_oxdiff_formula         'C51 H95 B Na O4 Si8 U1 '
_shelx_estimated_absorpt_t_max   0.567
_shelx_estimated_absorpt_t_min   0.379
_reflns_odcompleteness_completeness 99.43
_reflns_odcompleteness_iscentric 1
_reflns_odcompleteness_theta     66.97
_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. Shared sites
{C60A, C60B}
{C63A, C63B}
3. Restrained distances
 O1A-C51
 1.42 with sigma of 0.02
 O1A-C47A
 1.42 with sigma of 0.02
 C50A-C47A
 1.52 with sigma of 0.02
 C48A-C47A
 1.52 with sigma of 0.02
 C47A-C49A
 1.52 with sigma of 0.02
 C60B-C61B
 1.5 with sigma of 0.02
 C60B-C62B
 1.5 with sigma of 0.02
 O4A-C60A
 1.45 with sigma of 0.02
 C61B-C62B
 2.45 with sigma of 0.04
 C63B-C62B
 2.45 with sigma of 0.04
 C64A-C62A
 2.45 with sigma of 0.04
 C64B-C61B
 2.45 with sigma of 0.04
 C64A-C60A
 2.35 with sigma of 0.04
 C49B-C50B
 2.35 with sigma of 0.04
 C49B-C47B \\sim C48B-C50B
 with sigma of 0.02
 O4A-C64A \\sim O4B-C64B
 with sigma of 0.02
 C60B-C62B \\sim C60A-C61A
 with sigma of 0.02
 O1B-C50B \\sim O1B-C49B
 with sigma of 0.02
4. Rigid bond restraints
 C64A, C64B
 with sigma for 1-2 distances of 0.01 and sigma for 1-3 distances of 0.01
5. Uiso/Uaniso restraints and constraints
C64A \\sim C64B: within 2A with sigma of 0.04 and sigma for terminal atoms of
0.08
O4B \\sim O4A: within 2A with sigma of 0.04 and sigma for terminal atoms of 0.08
Uanis(C62A) \\sim Ueq, Uanis(C62B) \\sim Ueq: with sigma of 0.01 and sigma for
terminal atoms of 0.01
Uanis(C64A) \\sim Ueq, Uanis(C64B) \\sim Ueq: with sigma of 0.02 and sigma for
terminal atoms of 0.02
Uanis(C63A) \\sim Ueq, Uanis(C63B) \\sim Ueq: with sigma of 0.02 and sigma for
terminal atoms of 0.02
Uanis(C60B) \\sim Ueq, Uanis(C60A) \\sim Ueq: with sigma of 0.02 and sigma for
terminal atoms of 0.02
Uanis(O1B) \\sim Ueq: with sigma of 0.02 and sigma for terminal atoms of 0.02
Uanis(C49B) \\sim Ueq: with sigma of 0.02 and sigma for terminal atoms of 0.04
Uanis(C63A) = Uanis(C63B)
Uanis(C60A) = Uanis(C60B)
Uanis(C64A) = Uanis(C64B)
Uanis(C62A) = Uanis(C62B)
Uanis(C61A) = Uanis(C61B)
Uanis(O1A) = Uanis(O1B)
6. Rigid body (RIGU) restrains
 C47B, C48B, C49B, C50B
 with sigma for 1-2 distances of 0.01 and sigma for 1-3 distances of 0.01
 C51, C47B, C48A, C50A
 with sigma for 1-2 distances of 0.004 and sigma for 1-3 distances of 0.004
 C49B, C49A, C48B, C50B
 with sigma for 1-2 distances of 0.004 and sigma for 1-3 distances of 0.004
7. Others
 Fixed Sof: O1A(0.7) C47A(0.7) C48A(0.7) H48A(0.7) H48B(0.7) H48C(0.7)
 C49A(0.7) H49A(0.7) H49B(0.7) H49C(0.7) C50A(0.7) H50A(0.7) H50B(0.7)
 H50C(0.7) O1B(0.3) C48B(0.3) H48D(0.3) H48E(0.3) C49B(0.3) H49D(0.3) H49E(0.3)
 C50B(0.3) H50D(0.3) H50E(0.3) C47B(0.3) H47A(0.3) H47B(0.3) O4A(0.6) C60A(0.6)
 C63A(0.6) H63A(0.6) H63B(0.6) H63C(0.6) C64A(0.6) H64A(0.6) H64B(0.6)
 H64C(0.6) C61A(0.6) H61A(0.6) H61B(0.6) H61C(0.6) C62A(0.6) H62A(0.6)
 H62B(0.6) H62C(0.6) O4B(0.4) C64B(0.4) H64D(0.4) H64E(0.4) H64F(0.4) C60B(0.4)
 C61B(0.4) H61D(0.4) H61E(0.4) H61F(0.4) C63B(0.4) H63D(0.4) H63E(0.4)
 H63F(0.4) C62B(0.4) H62D(0.4) H62E(0.4) H62F(0.4)
8.a Secondary CH2 refined with riding coordinates:
 C23(H23A,H23B), C48B(H48D,H48E), C49B(H49D,H49E), C50B(H50D,H50E), C47B(H47A,
 H47B)
8.b Me refined with riding coordinates:
 C51(H51A,H51B,H51C), C63A(H63A,H63B,H63C), C61A(H61A,H61B,H61C), C63B(H63D,
 H63E,H63F)
8.c Idealised Me refined as rotating group:
 C24(H24A,H24B,H24C), C29(H29A,H29B,H29C), C10(H10A,H10B,H10C), C21(H21A,H21B,
 H21C), C9(H9A,H9B,H9C), C30(H30A,H30B,H30C), C32(H32A,H32B,H32C), C22(H22A,
 H22B,H22C), C16(H16A,H16B,H16C), C15(H15A,H15B,H15C), C19(H19A,H19B,H19C),
 C11(H11A,H11B,H11C), C17(H17A,H17B,H17C), C18(H18A,H18B,H18C), C13(H13A,H13B,
 H13C), C25(H25A,H25B,H25C), C20(H20A,H20B,H20C), C14(H14A,H14B,H14C), C28(H28A,
 H28B,H28C), C39(H39A,H39B,H39C), C33(H33A,H33B,H33C), C31(H31A,H31B,H31C),
 C12(H12A,H12B,H12C), C26(H26A,H26B,H26C), C35(H35A,H35B,H35C), C40(H40A,H40B,
 H40C), C27(H27A,H27B,H27C), C37(H37A,H37B,H37C), C34(H34A,H34B,H34C), C41(H41A,
 H41B,H41C), C36(H36A,H36B,H36C), C48A(H48A,H48B,H48C), C49A(H49A,H49B,H49C),
 C50A(H50A,H50B,H50C), C64A(H64A,H64B,H64C), C62A(H62A,H62B,H62C), C64B(H64D,
 H64E,H64F), C61B(H61D,H61E,H61F), C62B(H62D,H62E,H62F)
;
_shelx_res_checksum              85495
_olex2_date_sample_data_collection 2019-02-02
_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 1.375
_oxdiff_exptl_absorpt_empirical_full_min 0.788