Stereo-selectivity switchable ROP of rac-β-butyrolactone initiated by salan-ligated rare-earth metal amide complexes: the key role of the substituents on ligand frameworks.
Zhuo, Zhixing; Zhang, Chen; Luo, Yunjie; Wang, Yaorong; Yao, Yingming; Yuan, Dan; Cui, Dongmei; Chemical communications (Cambridge, England) 54 (2018) 11998–12001; doi:10.1039/c8cc05469j

data_7125347
_publ_section_title
;
 Stereo-selectivity switchable ROP of rac-\b-butyrolactone initiated by
 salan-ligated rare-earth metal amide complexes: the key role of the
 substituents on ligand frameworks.
;
_journal_issue                   85
_journal_name_full               'Chemical communications (Cambridge, England)'
_journal_page_first              11998
_journal_page_last               12001
_journal_paper_doi               10.1039/c8cc05469j
_journal_volume                  54
_journal_year                    2018
_chemical_formula_sum            'C50 H76 N3 O2 Si2 Yb'
_chemical_formula_weight         980.35
_chemical_properties_physical    Air-sensitive,Moisture-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   geom
_audit_creation_method           SHELXL-2018/3
_audit_update_record
;
2018-07-03 deposited with the CCDC.
2018-08-28 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 95.218(6)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   15.2120(12)
_cell_length_b                   16.174(2)
_cell_length_c                   20.7742(15)
_cell_measurement_reflns_used    10749
_cell_measurement_temperature    293(2)
_cell_measurement_theta_max      29.7440
_cell_measurement_theta_min      3.4230
_cell_volume                     5090.1(8)
_computing_structure_refinement  'SHELXL-2018/3 (Sheldrick, 2018)'
_diffrn_ambient_temperature      293(2)
_diffrn_measured_fraction_theta_full 0.991
_diffrn_measured_fraction_theta_max 0.991
_diffrn_measurement_device_type  'Xcalibur, Atlas, Gemini'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.1537
_diffrn_reflns_av_unetI/netI     0.1295
_diffrn_reflns_Laue_measured_fraction_full 0.991
_diffrn_reflns_Laue_measured_fraction_max 0.991
_diffrn_reflns_limit_h_max       18
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       19
_diffrn_reflns_limit_k_min       -19
_diffrn_reflns_limit_l_max       24
_diffrn_reflns_limit_l_min       -24
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_diffrn_reflns_point_group_measured_fraction_full 0.991
_diffrn_reflns_point_group_measured_fraction_max 0.991
_diffrn_reflns_theta_full        25.000
_diffrn_reflns_theta_max         25.000
_diffrn_reflns_theta_min         2.855
_exptl_absorpt_coefficient_mu    1.923
_exptl_crystal_colour            'clear dark yellow'
_exptl_crystal_density_diffrn    1.279
_exptl_crystal_description       needle
_exptl_crystal_F_000             2044
_refine_diff_density_max         2.169
_refine_diff_density_min         -2.126
_refine_diff_density_rms         0.225
_refine_ls_extinction_method     none
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_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
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_refine_ls_number_reflns         8875
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_refine_ls_R_factor_all          0.1249
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_refine_ls_shift/su_max          0.004
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0400P)^2^+56.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
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_reflns_number_total             8875
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c8cc05469j2.cif
_cod_data_source_block           spherical
_cod_original_cell_volume        5090.0(8)
_cod_original_sg_symbol_H-M      'P 21/c'
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_shelx_res_checksum              78549