A Stereoselective Approach to the Azaspiro[5.5]undecane Ring System Using a Conjugate Addition/Dipolar Cycloaddition Cascade: Application to the Total Synthesis of (±)-2,7,8-epi-Perhydrohistrionicotoxin
Michael S. Wilson; Albert Padwa; Journal of Organic Chemistry 73 (2008) 9601–9609; doi:10.1021/jo801295e

data_4023919
_publ_section_title
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 A Stereoselective Approach to the Azaspiro[5.5]undecane Ring System
 Using a Conjugate Addition/Dipolar Cycloaddition Cascade: Application
 to the Total Synthesis of (+-)-2,7,8-epi-Perhydrohistrionicotoxin
;
_journal_name_full               'Journal of Organic Chemistry'
_journal_page_first              9601
_journal_page_last               9609
_journal_paper_doi               10.1021/jo801295e
_journal_volume                  73
_journal_year                    2008
_chemical_formula_sum            'C35 H51 N3 O5 S'
_chemical_formula_weight         625.85
_space_group_IT_number           61
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  '-P 2ac 2ab'
_symmetry_space_group_name_H-M   'P b c a'
_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                 90.00
_cell_angle_gamma                90.00
_cell_formula_units_Z            8
_cell_length_a                   20.3831(14)
_cell_length_b                   14.5284(9)
_cell_length_c                   23.2366(15)
_cell_measurement_reflns_used    6787
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      59.87
_cell_measurement_theta_min      3.80
_cell_volume                     6881.1(8)
_computing_cell_refinement       'Bruker SMART'
_computing_data_collection       'Bruker SMART'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.945
_diffrn_measured_fraction_theta_max 0.945
_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           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0656
_diffrn_reflns_av_sigmaI/netI    0.0658
_diffrn_reflns_limit_h_max       22
_diffrn_reflns_limit_h_min       -20
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       26
_diffrn_reflns_limit_l_min       -25
_diffrn_reflns_number            52658
_diffrn_reflns_theta_full        66.05
_diffrn_reflns_theta_max         66.05
_diffrn_reflns_theta_min         3.80
_exptl_absorpt_coefficient_mu    1.185
_exptl_absorpt_correction_T_max  0.9009
_exptl_absorpt_correction_T_min  0.4221
_exptl_absorpt_correction_type   multi-scan
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.208
_exptl_crystal_density_meas      0
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       'flat needle'
_exptl_crystal_F_000             2704
_exptl_crystal_size_max          0.88
_exptl_crystal_size_mid          0.24
_exptl_crystal_size_min          0.09
_refine_diff_density_max         0.437
_refine_diff_density_min         -0.456
_refine_diff_density_rms         0.078
_refine_ls_extinction_coef       0.00031(6)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     SHELXL
_refine_ls_goodness_of_fit_ref   1.050
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     405
_refine_ls_number_reflns         5676
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.050
_refine_ls_R_factor_all          0.1128
_refine_ls_R_factor_gt           0.0457
_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^)+(0.1128P)^2^+0.0000P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1381
_refine_ls_wR_factor_ref         0.1775
_reflns_number_gt                3654
_reflns_number_total             5676
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            jo801295e_si_004.cif
_cod_data_source_block           a307s
_cod_depositor_comments
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The following automatic conversions were performed:
'_symmetry_cell_setting' value 'Orthorhombic' changed to 'orthorhombic'
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_enum 1527 2010-12-29 10:47:43Z saulius 
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_cod_database_code               4023919