Stereoselective Synthesis of Tabtoxinine-β-lactam by Using the Vinylogous Mukaiyama Aldol Reaction with Acetate-Type Vinylketene Silyl N,O-Acetal and α-Keto-β-lactam
Ejima, Hirotaka; Wakita, Fumihiro; Imamura, Ryo; Kato, Takuya; Hosokawa, Seijiro; Organic Letters  (2017) –; doi:10.1021/acs.orglett.7b00814

data_1545977
_publ_section_title
;
 Stereoselective Synthesis of Tabtoxinine-\b-lactam by Using the
 Vinylogous Mukaiyama Aldol Reaction with Acetate-Type Vinylketene Silyl
 N,O-Acetal and \a-Keto-\b-lactam
;
_journal_name_full               'Organic Letters'
_journal_paper_doi               10.1021/acs.orglett.7b00814
_journal_year                    2017
_chemical_absolute_configuration 'CHOOSE rm ad rmad syn or unk'
_chemical_formula_moiety         'C33 H36 N2 O6'
_chemical_formula_sum            'C33 H36 N2 O6'
_chemical_formula_weight         556.66
_space_group_crystal_system      orthorhombic
_space_group_IT_number           19
_space_group_name_Hall           'P 2ac 2ab'
_space_group_name_H-M_alt        'P 21 21 21'
_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
_cell_angle_alpha                90.0000
_cell_angle_beta                 90.0000
_cell_angle_gamma                90.0000
_cell_formula_units_Z            4
_cell_length_a                   8.7243(4)
_cell_length_b                   12.5040(5)
_cell_length_c                   26.5448(10)
_cell_measurement_reflns_used    21375
_cell_measurement_temperature    296
_cell_measurement_theta_max      27.43
_cell_measurement_theta_min      3.07
_cell_volume                     2895.7(2)
_computing_cell_refinement       'RAPID AUTO'
_computing_data_collection       'RAPID AUTO (Rigaku, ????)'
_computing_data_reduction        'RAPID AUTO'
_computing_molecular_graphics    'CrystalStructure 4.2'
_computing_publication_material  'CrystalStructure 4.2 (Rigaku, 2015)'
_computing_structure_refinement  'SHELXL Version 2014/6 (Sheldrick, 2008)'
_computing_structure_solution    'SIR92 (Altomare, et al., 1994)'
_diffrn_ambient_temperature      296
_diffrn_detector_area_resol_mean 10.000
_diffrn_measured_fraction_theta_full 0.997
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'Rigaku R-AXIS RAPID'
_diffrn_measurement_method       \w
_diffrn_radiation_type           'Mo K\a'
_diffrn_radiation_wavelength     0.71075
_diffrn_reflns_av_R_equivalents  0.0259
_diffrn_reflns_Laue_measured_fraction_full 0.997
_diffrn_reflns_Laue_measured_fraction_max 0.996
_diffrn_reflns_limit_h_max       11
_diffrn_reflns_limit_h_min       -11
_diffrn_reflns_limit_k_max       16
_diffrn_reflns_limit_k_min       -14
_diffrn_reflns_limit_l_max       34
_diffrn_reflns_limit_l_min       -34
_diffrn_reflns_number            28014
_diffrn_reflns_point_group_measured_fraction_full 0.998
_diffrn_reflns_point_group_measured_fraction_max 0.997
_diffrn_reflns_theta_full        25.242
_diffrn_reflns_theta_max         27.462
_diffrn_reflns_theta_min         3.070
_diffrn_standards_number         0
_exptl_absorpt_coefficient_mu    0.088
_exptl_absorpt_correction_T_max  0.983
_exptl_absorpt_correction_T_min  0.774
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'ABSCOR (Rigaku, 1995)'
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.277
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       block
_exptl_crystal_F_000             1184.00
_exptl_crystal_size_max          0.500
_exptl_crystal_size_mid          0.400
_exptl_crystal_size_min          0.200
_refine_diff_density_max         0.85
_refine_diff_density_min         -0.30
_refine_ls_abs_structure_details
;
 Flack x determined using 2407 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.1(2)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.045
_refine_ls_hydrogen_treatment    constr
_refine_ls_number_parameters     370
_refine_ls_number_reflns         6604
_refine_ls_number_restraints     0
_refine_ls_R_factor_all          0.0518
_refine_ls_R_factor_gt           0.0462
_refine_ls_shift/su_max          0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w = 1/[\s^2^(Fo^2^)+(0.0681P)^2^+1.2224P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1220
_refine_ls_wR_factor_ref         0.1270
_reflns_Friedel_coverage         0.771
_reflns_Friedel_fraction_full    1.000
_reflns_Friedel_fraction_max     0.997
_reflns_number_gt                6015
_reflns_number_total             6604
_reflns_threshold_expression     F^2^>2.0\s(F^2^)
_cod_data_source_file            ol7b00814_si_001.cif
_cod_data_source_block           20170201ejima
_cod_database_code               1545977
_shelxl_version_number           2014/6
_shelx_res_checksum              14845
_shelx_hkl_checksum              81632