Unveiling the Takai Olefination Reagent via Tris( tert-butoxy)siloxy Variants.
Werner, Daniel; Anwander, Reiner; Journal of the American Chemical Society 140 (2018) 14334–14341; doi:10.1021/jacs.8b08739

data_4133159
_publ_section_title
;
 Unveiling the Takai Olefination Reagent via Tris( tert-butoxy)siloxy
 Variants.
;
_journal_issue                   43
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              14334
_journal_page_last               14341
_journal_paper_doi               10.1021/jacs.8b08739
_journal_volume                  140
_journal_year                    2018
_chemical_formula_moiety         '2(C12 H27 Cr I O4 Si)'
_chemical_formula_sum            'C24 H54 Cr2 I2 O8 Si2'
_chemical_formula_weight         884.65
_space_group_crystal_system      monoclinic
_space_group_IT_number           14
_space_group_name_Hall           '-P 2yn'
_space_group_name_H-M_alt        'P 1 21/n 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     iterative
_atom_sites_solution_secondary   difmap
_audit_creation_date             2017-12-14
_audit_creation_method
;
Olex2 1.2
(compiled 2017.08.10 svn.r3458 for OlexSys, GUI svn.r5381)
;
_cell_angle_alpha                90.00
_cell_angle_beta                 104.6588(19)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   17.8832(19)
_cell_length_b                   9.1254(10)
_cell_length_c                   23.860(3)
_cell_measurement_reflns_used    8342
_cell_measurement_temperature    100
_cell_measurement_theta_max      26.720
_cell_measurement_theta_min      2.52
_cell_volume                     3767.0(7)
_computing_cell_refinement       'SAINT v8.37A (Bruker, 2015)'
_computing_data_reduction        'SAINT v8.37A (Bruker, 2015)'
_computing_molecular_graphics    'Olex2 (Dolomanov et al., 2009)'
_computing_publication_material  'Olex2 (Dolomanov et al., 2009)'
_computing_structure_refinement  'XL (Sheldrick, 2008)'
_computing_structure_solution
;
Superflip (Palatinus & Chapuis, 2007;Palatinus & van der Lee, 2008;
Palatinus et al., 2012)
;
_diffrn_ambient_temperature      100
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0897
_diffrn_reflns_av_unetI/netI     0.0556
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -22
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       28
_diffrn_reflns_limit_l_min       -30
_diffrn_reflns_number            46122
_diffrn_reflns_theta_full        26.80
_diffrn_reflns_theta_max         26.80
_diffrn_reflns_theta_min         1.28
_diffrn_source                   'fine-focus sealed tube'
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    2.316
_exptl_absorpt_correction_T_max  0.7454
_exptl_absorpt_correction_T_min  0.6056
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
'SADABS-2016/2 (Bruker,2016/2) was used for absorption correction. wR2(int) was 0.1181 before and 0.0517 after correction. The Ratio of minimum to maximum transmission is 0.8124. The \l/2 correction factor is Not present.'
_exptl_crystal_colour            'clear colourless'
_exptl_crystal_colour_lustre     clear
_exptl_crystal_colour_primary    colourless
_exptl_crystal_density_diffrn    1.560
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1776
_exptl_crystal_size_max          0.1
_exptl_crystal_size_mid          0.05
_exptl_crystal_size_min          0.05
_refine_diff_density_max         1.311
_refine_diff_density_min         -0.874
_refine_diff_density_rms         0.117
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.054
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     381
_refine_ls_number_reflns         8049
_refine_ls_number_restraints     24
_refine_ls_restrained_S_all      1.053
_refine_ls_R_factor_all          0.0661
_refine_ls_R_factor_gt           0.0398
_refine_ls_shift/su_max          0.001
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0356P)^2^+2.8172P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0793
_refine_ls_wR_factor_ref         0.0880
_reflns_number_gt                6007
_reflns_number_total             8049
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja8b08739_si_008.cif
_cod_data_source_block           6b
_cod_database_code               4133159
_olex2_refinement_description
;
1. Fixed Uiso
 At 1.5 times of:
  All C(H,H,H) groups
2. Uiso/Uaniso restraints and constraints
Uanis(C25) \\sim Ueq: with sigma of 0.001 and sigma for terminal atoms of 0.001
Uanis(C24) \\sim Ueq: with sigma of 0.001 and sigma for terminal atoms of 0.001
Uanis(C22) \\sim Ueq: with sigma of 0.001 and sigma for terminal atoms of 0.001
Uanis(C26) \\sim Ueq: with sigma of 0.001 and sigma for terminal atoms of 0.001
3. Others
 Fixed Sof: C22(0.5) H22A(0.5) H22B(0.5) H22C(0.5) C25(0.5) H25A(0.5)
 H25B(0.5) H25C(0.5) C26(0.5) H26A(0.5) H26B(0.5) H26C(0.5) C24(0.5) H24A(0.5)
 H24B(0.5) H24C(0.5)
4.a Idealised Me refined as rotating group:
 C20(H20A,H20B,H20C), C4(H4A,H4B,H4C), C10(H10A,H10B,H10C), C8(H8A,H8B,H8C),
 C2(H2A,H2B,H2C), C7(H7A,H7B,H7C), C18(H18A,H18B,H18C), C3(H3A,H3B,H3C),
 C15(H15A,H15B,H15C), C14(H14A,H14B,H14C), C16(H16A,H16B,H16C), C11(H11A,H11B,
 H11C), C6(H6A,H6B,H6C), C12(H12A,H12B,H12C), C19(H19A,H19B,H19C), C23(H23A,
 H23B,H23C), C22(H22A,H22B,H22C), C25(H25A,H25B,H25C), C26(H26A,H26B,H26C),
 C24(H24A,H24B,H24C)
;
_olex2_submission_special_instructions 'No special instructions were received'