Thionium Ion Initiated Medium-Sized Ring Formation: The Total Synthesis of Asteriscunolide D
Barry M. Trost; Aaron C. Burns; Mark J. Bartlett; Thomas Tautz; Andrew H. Weiss; Journal of the American Chemical Society 134 (2012) 1474–1477; doi:10.1021/ja210986f

data_4117350
_publ_contact_author_address     'Department of Chemistry, Stanford University'
_publ_contact_author_email       acburns@stanford.edu
_publ_contact_author_name        'Aaron Burns'
_publ_section_title
;
 Thionium Ion Initiated Medium-Sized Ring Formation: The Total Synthesis
 of Asteriscunolide D
;
_journal_name_full               'Journal of the American Chemical Society'
_journal_page_first              1474
_journal_page_last               1477
_journal_paper_doi               10.1021/ja210986f
_journal_volume                  134
_journal_year                    2012
_chemical_absolute_configuration ad
_chemical_formula_moiety         'C21 H24 O3 S'
_chemical_formula_sum            'C21 H24 O3 S'
_chemical_formula_weight         356.46
_space_group_IT_number           4
_symmetry_cell_setting           monoclinic
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 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                 97.202(2)
_cell_angle_gamma                90.00
_cell_formula_units_Z            2
_cell_length_a                   5.8691(2)
_cell_length_b                   11.2351(4)
_cell_length_c                   14.3074(5)
_cell_measurement_reflns_used    5262
_cell_measurement_temperature    100(2)
_cell_measurement_theta_max      69.18
_cell_measurement_theta_min      3.12
_cell_volume                     935.99(6)
_computing_cell_refinement       'Bruker SAINT v7.66A'
_computing_data_collection       'Bruker APEX-II v2010-7'
_computing_data_reduction        'Bruker SAINT v7.66A'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      100(2)
_diffrn_detector_area_resol_mean 8.33
_diffrn_measured_fraction_theta_full 0.932
_diffrn_measured_fraction_theta_max 0.932
_diffrn_measurement_device_type  'Bruker APEX'
_diffrn_measurement_method       'combination of \w and \f-scans '
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'fine-focus sealed tube'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0297
_diffrn_reflns_av_sigmaI/netI    0.0353
_diffrn_reflns_limit_h_max       5
_diffrn_reflns_limit_h_min       -6
_diffrn_reflns_limit_k_max       13
_diffrn_reflns_limit_k_min       -13
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            8446
_diffrn_reflns_theta_full        69.60
_diffrn_reflns_theta_max         69.60
_diffrn_reflns_theta_min         3.11
_exptl_absorpt_coefficient_mu    1.664
_exptl_absorpt_correction_T_max  0.9217
_exptl_absorpt_correction_T_min  0.5473
_exptl_absorpt_correction_type   numerical
_exptl_absorpt_process_details   'SADABS, Sheldrick, 2008'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.265
_exptl_crystal_description       rod
_exptl_crystal_F_000             380
_exptl_crystal_size_max          0.76
_exptl_crystal_size_mid          0.13
_exptl_crystal_size_min          0.07
_refine_diff_density_max         0.331
_refine_diff_density_min         -0.131
_refine_diff_density_rms         0.043
_refine_ls_abs_structure_details
'Flack H D (1983), Acta Cryst. A39, 876-881; 1382 Friedel Pairs measured'
_refine_ls_abs_structure_Flack   0.037(16)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.055
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     229
_refine_ls_number_reflns         3122
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.054
_refine_ls_R_factor_all          0.0364
_refine_ls_R_factor_gt           0.0347
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'calc w=1/[\s^2^(Fo^2^)+(0.0482P)^2^+0.2489P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0870
_refine_ls_wR_factor_ref         0.0883
_reflns_number_gt                3008
_reflns_number_total             3122
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ja210986f_si_002.cif
_cod_data_source_block           su1126
_cod_database_code               4117350