Di-tert-butylisobutylsilyl, another useful protecting group.
Liang, Huan; Hu, Lin; Corey, E. J.; Organic letters 13 (2011) 4120–4123; doi:10.1021/ol201640y

data_1502347
_publ_section_title
;
 Di-tert-butylisobutylsilyl, another useful protecting group.
;
_journal_issue                   15
_journal_name_full               'Organic letters'
_journal_page_first              4120
_journal_page_last               4123
_journal_paper_doi               10.1021/ol201640y
_journal_volume                  13
_journal_year                    2011
_chemical_formula_sum            'C18 H31 Br O Si'
_chemical_formula_weight         371.43
_space_group_IT_number           14
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  '-P 2ybc'
_symmetry_space_group_name_H-M   'P 1 21/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-97
_cell_angle_alpha                90.00
_cell_angle_beta                 100.770(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            4
_cell_length_a                   7.9868(14)
_cell_length_b                   16.291(3)
_cell_length_c                   15.104(3)
_cell_measurement_reflns_used    11155
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      23.6
_cell_measurement_theta_min      2.50
_cell_volume                     1930.6(6)
_computing_cell_refinement       'SAINT 7.46A (Bruker-AXS, 2009)'
_computing_data_collection       'APEX2 v2009.3.0 (Bruker-AXS, 2009)'
_computing_data_reduction        'SAINT 7.46A (Bruker-AXS, 2009)'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.998
_diffrn_measurement_device_type  'CCD area detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0362
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_diffrn_reflns_limit_h_max       10
_diffrn_reflns_limit_h_min       -10
_diffrn_reflns_limit_k_max       21
_diffrn_reflns_limit_k_min       -21
_diffrn_reflns_limit_l_max       20
_diffrn_reflns_limit_l_min       -20
_diffrn_reflns_number            36096
_diffrn_reflns_theta_full        28.67
_diffrn_reflns_theta_max         28.67
_diffrn_reflns_theta_min         1.86
_exptl_absorpt_coefficient_mu    2.190
_exptl_absorpt_correction_T_max  0.7791
_exptl_absorpt_correction_T_min  0.6685
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.278
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             784
_exptl_crystal_size_max          0.20
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_refine_diff_density_max         0.800
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_refine_ls_number_reflns         4967
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_refine_ls_restrained_S_all      1.012
_refine_ls_R_factor_all          0.0355
_refine_ls_R_factor_gt           0.0259
_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^)+(0.0273P)^2^+0.8833P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0589
_refine_ls_wR_factor_ref         0.0624
_reflns_number_gt                4211
_reflns_number_total             4967
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol201640y_si_004.cif
_cod_data_source_block           C2-33
_cod_depositor_comments
;
The following automatic conversions were performed:

'_symmetry_cell_setting' value 'Monoclinic' changed to 'monoclinic'
according to /home/saulius/struct/CIF-dictionaries/cif_core.dic
dictionary named 'cif_core.dic' version 2.4.1 from 2010-06-29.

Automatic conversion script
Id: cif_fix_values 1715 2011-07-08 13:25:40Z adriana 
;
_cod_original_cell_volume        1930.7(6)
_cod_original_sg_symbol_H-M      P21/c
_cod_database_code               1502347