Highly enantioenriched homoenolate reagents by asymmetric gamma-deprotonation of achiral 1-silyl-substituted 1-alkenyl carbamates.
Reuber, Jenny; Fröhlich, Roland; Hoppe, Dieter; Organic letters 6 (2004) 783–786; doi:10.1021/ol0364677

data_1506912
_publ_section_title
;
 Highly enantioenriched homoenolate reagents by asymmetric
 gamma-deprotonation of achiral 1-silyl-substituted 1-alkenyl carbamates.
;
_journal_issue                   5
_journal_name_full               'Organic letters'
_journal_page_first              783
_journal_page_last               786
_journal_paper_doi               10.1021/ol0364677
_journal_volume                  6
_journal_year                    2004
_chemical_formula_sum            'C24 H39 N O3 Si'
_chemical_formula_weight         417.65
_space_group_IT_number           19
_symmetry_cell_setting           orthorhombic
_symmetry_space_group_name_Hall  'P 2ac 2ab'
_symmetry_space_group_name_H-M   'P 21 21 21'
_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                   9.895(1)
_cell_length_b                   11.670(1)
_cell_length_c                   22.943(1)
_cell_measurement_temperature    198(2)
_cell_volume                     2649.3(4)
_computing_cell_refinement       'Collect (Nonius B.V., 1998)'
_computing_data_collection       'Collect (Nonius B.V., 1998)'
_computing_data_reduction        'Denzo-SMN (Otwinwoski & Minor, 1997)'
_computing_molecular_graphics    'Diamond (Brandenburg, 1997)'
_computing_publication_material  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_refinement  'SHELXL-97 (Sheldrick, 1997)'
_computing_structure_solution    'SHELXS-97 (Sheldrick, 1990)'
_diffrn_ambient_temperature      198(2)
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Nonius KappaCCD'
_diffrn_measurement_method       '\w and \f scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_source         'rotating anode Nonius FR591'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0669
_diffrn_reflns_av_sigmaI/netI    0.0588
_diffrn_reflns_limit_h_max       12
_diffrn_reflns_limit_h_min       -12
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       30
_diffrn_reflns_limit_l_min       -27
_diffrn_reflns_number            20230
_diffrn_reflns_theta_full        27.88
_diffrn_reflns_theta_max         27.88
_diffrn_reflns_theta_min         1.78
_exptl_absorpt_coefficient_mu    0.110
_exptl_absorpt_correction_T_max  0.9784
_exptl_absorpt_correction_T_min  0.9626
_exptl_absorpt_correction_type   empirical
_exptl_absorpt_process_details   'SORTAV (Blessing, 1995 & 1997)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.047
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             912
_exptl_crystal_size_max          0.35
_exptl_crystal_size_mid          0.20
_exptl_crystal_size_min          0.20
_refine_diff_density_max         0.217
_refine_diff_density_min         -0.183
_refine_diff_density_rms         0.035
_refine_ls_abs_structure_details 'Flack H D (1983), Acta Cryst. A39, 876-881'
_refine_ls_abs_structure_Flack   -0.08(12)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.028
_refine_ls_hydrogen_treatment    'refined as riding atoms'
_refine_ls_matrix_type           full
_refine_ls_number_parameters     274
_refine_ls_number_reflns         6233
_refine_ls_number_restraints     0
_refine_ls_restrained_S_all      1.028
_refine_ls_R_factor_all          0.0774
_refine_ls_R_factor_gt           0.0470
_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^)+(0.0561P)^2^+0.1324P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1048
_refine_ls_wR_factor_ref         0.1166
_reflns_number_gt                4461
_reflns_number_total             6233
_reflns_threshold_expression     >2sigma(I)
_cod_data_source_file            ol0364677si20040127_124415.cif
_cod_data_source_block           hop2524
_cod_original_sg_symbol_H-M      P212121
_cod_database_code               1506912