Highly Discriminative and Chemoselective Deprotection/Transformations of Acetals with the Combination of Trialkylsilyl Triflate/2,4,6-Collidine.
Ohta, Reiya; Matsumoto, Nao; Ueyama, Yoshifumi; Kuboki, Yuichi; Aoyama, Hiroshi; Murai, Kenichi; Arisawa, Mitsuhiro; Maegawa, Tomohiro; Fujioka, Hiromichi; The Journal of organic chemistry 83 (2018) 6432–6443; doi:10.1021/acs.joc.8b00675

data_4035857
_publ_section_title
;
 Highly Discriminative and Chemoselective Deprotection/Transformations of
 Acetals with the Combination of Trialkylsilyl Triflate/2,4,6-Collidine.
;
_journal_issue                   12
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              6432
_journal_page_last               6443
_journal_paper_doi               10.1021/acs.joc.8b00675
_journal_volume                  83
_journal_year                    2018
_chemical_formula_moiety         'C9 H12 F3 N O3 S'
_chemical_formula_sum            'C9 H12 F3 N O3 S'
_chemical_formula_weight         271.25
_space_group_crystal_system      monoclinic
_space_group_IT_number           15
_space_group_name_Hall           '-C 2yc'
_space_group_name_H-M_alt        'C 1 2/c 1'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_cell_angle_alpha                90.0000
_cell_angle_beta                 95.622(7)
_cell_angle_gamma                90.0000
_cell_formula_units_Z            8
_cell_length_a                   17.1050(13)
_cell_length_b                   8.9423(6)
_cell_length_c                   16.1115(15)
_cell_measurement_reflns_used    3319
_cell_measurement_temperature    100
_cell_measurement_theta_max      74.71
_cell_measurement_theta_min      5.52
_cell_volume                     2452.5(3)
_computing_cell_refinement       'CrysAlisPro 1.171.39.16b (Rigaku OD, 2015)'
_computing_data_collection       'CrysAlisPro 1.171.39.16b (Rigaku OD, 2015)'
_computing_data_reduction        'CrysAlisPro 1.171.39.16b (Rigaku OD, 2015)'
_computing_molecular_graphics    'CrystalStructure 4.2.4'
_computing_publication_material  'CrystalStructure 4.2.4 (Rigaku, 2016)'
_computing_structure_refinement  'SHELXL Version 2014/7 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXT Version 2014/5 (Sheldrick, 2014)'
_diffrn_ambient_temperature      100
_diffrn_detector_area_resol_mean 5.811
_diffrn_measured_fraction_theta_full 0.986
_diffrn_measured_fraction_theta_max 0.986
_diffrn_measurement_device_type  'Rigaku XtaLAB P200'
_diffrn_measurement_method       \w
_diffrn_radiation_type           'Cu K\a'
_diffrn_radiation_wavelength     1.54184
_diffrn_reflns_av_R_equivalents  0.1573
_diffrn_reflns_Laue_measured_fraction_full 0.986
_diffrn_reflns_Laue_measured_fraction_max 0.986
_diffrn_reflns_limit_h_max       20
_diffrn_reflns_limit_h_min       -19
_diffrn_reflns_limit_k_max       10
_diffrn_reflns_limit_k_min       -10
_diffrn_reflns_limit_l_max       10
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            9519
_diffrn_reflns_point_group_measured_fraction_full 0.986
_diffrn_reflns_point_group_measured_fraction_max 0.986
_diffrn_reflns_theta_full        67.684
_diffrn_reflns_theta_max         68.245
_diffrn_reflns_theta_min         5.197
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    2.730
_exptl_absorpt_correction_T_max  0.479
_exptl_absorpt_correction_T_min  0.233
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details
;
CrysAlisPro 1.171.39.16b (Rigaku Oxford Diffraction, 2015)
Empirical absorption correction using spherical harmonics,
 implemented in SCALE3 ABSPACK scaling algorithm.
;
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.469
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1120.00
_exptl_crystal_size_max          0.320
_exptl_crystal_size_mid          0.280
_exptl_crystal_size_min          0.270
_refine_diff_density_max         1.26
_refine_diff_density_min         -1.94
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.407
_refine_ls_hydrogen_treatment    constr
_refine_ls_number_parameters     157
_refine_ls_number_reflns         2219
_refine_ls_number_restraints     102
_refine_ls_R_factor_all          0.1708
_refine_ls_R_factor_gt           0.1461
_refine_ls_shift/su_max          0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.2000P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.3290
_refine_ls_wR_factor_ref         0.3500
_reflns_Friedel_coverage         0.000
_reflns_number_gt                1687
_reflns_number_total             2219
_reflns_threshold_expression     F^2^>2.0\s(F^2^)
_cod_data_source_file            jo8b00675_si_002.cif
_cod_data_source_block           SX16121R
_cod_database_code               4035857
_shelx_res_checksum              89564
_shelx_hkl_checksum              46683