Acyclic Remote 1,5- and 1,4,5-Stereocontrol in the Catalytic Stereoselective Reactions of β-Lactams with Aldehydes: The Effect of the N-Methylimidazole Ligand.
Plata, Paulina; Klimczak, Urszula; Zambroń, Bartosz K; The Journal of organic chemistry 83 (2018) 14527–14552; doi:10.1021/acs.joc.8b02333

data_4035685
_publ_section_title
;
 Acyclic Remote 1,5- and 1,4,5-Stereocontrol in the Catalytic
 Stereoselective Reactions of \b-Lactams with Aldehydes: The Effect of the
 N-Methylimidazole Ligand.
;
_journal_issue                   23
_journal_name_full               'The Journal of organic chemistry'
_journal_page_first              14527
_journal_page_last               14552
_journal_paper_doi               10.1021/acs.joc.8b02333
_journal_volume                  83
_journal_year                    2018
_chemical_absolute_configuration rm
_chemical_formula_moiety         'C18 H34 O5 Si'
_chemical_formula_sum            'C18 H34 O5 Si'
_chemical_formula_weight         358.54
_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'
_atom_sites_solution_hydrogens   geom
_atom_sites_solution_primary     direct
_atom_sites_solution_secondary   difmap
_audit_creation_method           SHELXL-2014
_cell_angle_alpha                90
_cell_angle_beta                 90.2238(19)
_cell_angle_gamma                90
_cell_formula_units_Z            8
_cell_length_a                   32.4209(9)
_cell_length_b                   8.0512(3)
_cell_length_c                   16.2619(5)
_cell_measurement_reflns_used    4309
_cell_measurement_temperature    296(2)
_cell_measurement_theta_max      68.49
_cell_measurement_theta_min      2.72
_cell_volume                     4244.8(2)
_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'
_computing_structure_refinement  'SHELXL-2014 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXL-2014 (Sheldrick, 2014)'
_diffrn_ambient_temperature      296(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.996
_diffrn_measurement_device_type  'Bruker APEX-II CCD'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_monochromator  graphite
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0918
_diffrn_reflns_av_unetI/netI     0.0721
_diffrn_reflns_Laue_measured_fraction_full 0.998
_diffrn_reflns_Laue_measured_fraction_max 0.996
_diffrn_reflns_limit_h_max       38
_diffrn_reflns_limit_h_min       -36
_diffrn_reflns_limit_k_max       9
_diffrn_reflns_limit_k_min       -9
_diffrn_reflns_limit_l_max       19
_diffrn_reflns_limit_l_min       -19
_diffrn_reflns_number            44135
_diffrn_reflns_point_group_measured_fraction_full 0.954
_diffrn_reflns_point_group_measured_fraction_max 0.948
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         68.491
_diffrn_reflns_theta_min         2.717
_diffrn_source                   'fine-focus sealed tube'
_exptl_absorpt_coefficient_mu    1.155
_exptl_absorpt_correction_T_max  0.8610
_exptl_absorpt_correction_T_min  0.4510
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   sadabs
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.122
_exptl_crystal_density_method    'not measured'
_exptl_crystal_description       needle
_exptl_crystal_F_000             1568
_exptl_crystal_size_max          0.819
_exptl_crystal_size_mid          0.136
_exptl_crystal_size_min          0.134
_refine_diff_density_max         0.504
_refine_diff_density_min         -0.272
_refine_diff_density_rms         0.065
_refine_ls_abs_structure_details
;
 Flack x determined using 1529 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.04(3)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   1.010
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     447
_refine_ls_number_reflns         7404
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.010
_refine_ls_R_factor_all          0.1223
_refine_ls_R_factor_gt           0.0646
_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^)+(0.1321P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.1720
_refine_ls_wR_factor_ref         0.2191
_reflns_Friedel_coverage         0.767
_reflns_Friedel_fraction_full    0.902
_reflns_Friedel_fraction_max     0.891
_reflns_number_gt                4309
_reflns_number_total             7404
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            jo8b02333_si_006.cif
_cod_data_source_block           BZ_G381_0m
_cod_original_sg_symbol_H-M      'C 2'
_cod_database_code               4035685
_shelx_estimated_absorpt_t_min   0.451
_shelx_estimated_absorpt_t_max   0.861
_shelxl_version_number           2014-3
_shelx_res_checksum              79231
_shelx_hkl_checksum              58541