Asymmetric synthesis of (-)-sedacryptine through a diastereoselective Mannich reaction of N,O-acetals with ketones.
Liu, Yi-Wen; Ma, Rui-Jun; Yan, Jia-Hang; Zhou, Zhu; Wei, Bang-Guo; Organic & biomolecular chemistry 16 (2018) 771–779; doi:10.1039/c7ob02989f

data_7156047
_publ_section_title
;
 Asymmetric synthesis of (-)-sedacryptine through a diastereoselective
 Mannich reaction of N,O-acetals with ketones.
;
_journal_issue                   5
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              771
_journal_page_last               779
_journal_paper_doi               10.1039/c7ob02989f
_journal_volume                  16
_journal_year                    2018
_chemical_absolute_configuration ad
_chemical_formula_sum            'C27 H43 N O4 Si'
_chemical_formula_weight         473.71
_space_group_crystal_system      monoclinic
_space_group_IT_number           5
_space_group_name_Hall           'C 2y'
_space_group_name_H-M_alt        'C 1 2 1'
_symmetry_space_group_name_Hall  'C 2y'
_symmetry_space_group_name_H-M   'C 1 2 1'
_atom_sites_solution_hydrogens   geom
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_audit_update_record
;
2017-11-14 deposited with the CCDC.
2018-01-02 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 91.380(2)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   33.6160(19)
_cell_length_b                   7.9053(4)
_cell_length_c                   11.1852(7)
_cell_measurement_reflns_used    9927
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      52.208
_cell_measurement_theta_min      4.848
_cell_volume                     2971.5(3)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX2'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
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_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
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_diffrn_measured_fraction_theta_full 0.991
_diffrn_measured_fraction_theta_max 0.992
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0320
_diffrn_reflns_av_unetI/netI     0.0199
_diffrn_reflns_Laue_measured_fraction_full 0.991
_diffrn_reflns_Laue_measured_fraction_max 0.992
_diffrn_reflns_limit_h_max       41
_diffrn_reflns_limit_h_min       -41
_diffrn_reflns_limit_k_max       9
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_diffrn_reflns_limit_l_min       -13
_diffrn_reflns_number            34676
_diffrn_reflns_point_group_measured_fraction_full 0.990
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_diffrn_reflns_theta_max         25.997
_diffrn_reflns_theta_min         2.424
_exptl_absorpt_coefficient_mu    0.107
_exptl_absorpt_correction_T_max  0.7456
_exptl_absorpt_correction_T_min  0.6943
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colorless
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_exptl_crystal_description       prismatic
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_refine_ls_abs_structure_details
; 
 Flack x determined using 2020 quotients [(I+)-(I-)]/[(I+)+(I-)] 
 (Parsons and Flack (2004), Acta Cryst. A60, s61). 
;
_refine_ls_abs_structure_Flack   -0.04(3)
_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   1.008
_refine_ls_hydrogen_treatment    constr
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_refine_ls_number_reflns         5776
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.008
_refine_ls_R_factor_all          0.0538
_refine_ls_R_factor_gt           0.0449
_refine_ls_shift/su_max          0.000
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0892P)^2^+0.3646P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1270
_refine_ls_wR_factor_ref         0.1375
_reflns_Friedel_coverage         0.856
_reflns_Friedel_fraction_full    0.989
_reflns_Friedel_fraction_max     0.990
_reflns_number_gt                4928
_reflns_number_total             5776
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c7ob02989f2.cif
_cod_data_source_block           mo_d8v17583_0m
_cod_depositor_comments
'Adding full bibliography for 7156046--7156047.cif.'
_cod_database_code               7156047
_shelx_estimated_absorpt_t_min   0.981
_shelx_estimated_absorpt_t_max   0.986
_shelxl_version_number           2013-4
_shelx_res_checksum              39706