Total synthesis of (+)-cassaine utilizing an anionic polycyclization strategy.
Ravindar, Kontham; Caron, Pierre-Yves; Deslongchamps, Pierre; Organic letters 15 (2013) 6270–6273; doi:10.1021/ol4030937

data_1513241
_publ_section_title
;
 Total synthesis of (+)-cassaine utilizing an anionic polycyclization
 strategy.
;
_journal_issue                   24
_journal_name_full               'Organic letters'
_journal_page_first              6270
_journal_page_last               6273
_journal_paper_doi               10.1021/ol4030937
_journal_volume                  15
_journal_year                    2013
_chemical_absolute_configuration rmad
_chemical_formula_moiety         'C24 H44 O3 Si'
_chemical_formula_sum            'C24 H44 O3 Si'
_chemical_formula_weight         408.68
_chemical_name_systematic
; 
 ? 
;
_space_group_IT_number           18
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2 2ab'
_symmetry_space_group_name_H-M   'P 21 21 2'
_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            4
_cell_length_a                   14.8863(2)
_cell_length_b                   25.4284(4)
_cell_length_c                   6.62020(10)
_cell_measurement_reflns_used    9679
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      28.2
_cell_measurement_theta_min      2.7
_cell_volume                     2505.98(6)
_computing_cell_refinement       SMART
_computing_data_collection       'SMART (Bruker, 2007)'
_computing_data_reduction        'SAINT+ (Bruker, 2007)'
_computing_molecular_graphics    'SHELXTL (Bruker, 2007)'
_computing_publication_material  SHELXTL
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 2008)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 2008)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.999
_diffrn_measured_fraction_theta_max 0.999
_diffrn_measurement_device_type  'Bruker APEX II 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  0.0408
_diffrn_reflns_av_sigmaI/netI    0.0165
_diffrn_reflns_limit_h_max       19
_diffrn_reflns_limit_h_min       -19
_diffrn_reflns_limit_k_max       33
_diffrn_reflns_limit_k_min       -33
_diffrn_reflns_limit_l_max       8
_diffrn_reflns_limit_l_min       -8
_diffrn_reflns_number            76691
_diffrn_reflns_theta_full        28.29
_diffrn_reflns_theta_max         28.29
_diffrn_reflns_theta_min         1.59
_exptl_absorpt_coefficient_mu    0.113
_exptl_absorpt_correction_T_max  0.9689
_exptl_absorpt_correction_T_min  0.9580
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS (Sheldrick, 1996)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.083
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       prism
_exptl_crystal_F_000             904
_exptl_crystal_size_max          0.40
_exptl_crystal_size_mid          0.32
_exptl_crystal_size_min          0.28
_refine_diff_density_max         0.341
_refine_diff_density_min         -0.175
_refine_diff_density_rms         0.042
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   0.04(11)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.066
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     263
_refine_ls_number_reflns         6220
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.066
_refine_ls_R_factor_all          0.0480
_refine_ls_R_factor_gt           0.0444
_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^)+(0.0767P)^2^+0.2452P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1221
_refine_ls_wR_factor_ref         0.1261
_reflns_number_gt                5735
_reflns_number_total             6220
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol4030937_si_002.cif
_cod_data_source_block           RK0_6140
_cod_database_code               1513241