Organocatalytic, Asymmetric Synthesis of Aza-Quaternary Center of Izidine Alkaloids: Synthesis of (-)-Tricyclic Skeleton of Cylindricine.
Srinivas, Kyatham; Singh, Nishant; Das, Dinabandhu; Koley, Dipankar; Organic letters  (2016) –; doi:10.1021/acs.orglett.6b03605

data_1544946
_publ_section_title
;
 Organocatalytic, Asymmetric Synthesis of Aza-Quaternary Center of Izidine
 Alkaloids: Synthesis of (-)-Tricyclic Skeleton of Cylindricine.
;
_journal_name_full               'Organic letters'
_journal_paper_doi               10.1021/acs.orglett.6b03605
_journal_year                    2016
_chemical_absolute_configuration ad
_chemical_formula_sum            'C19 H25 Br N2 O3'
_chemical_formula_weight         409.32
_chemical_name_common            DK-KS-Q87
_chemical_name_systematic
'((8R,8aS)-3-oxo-8a-propyloctahydroindolizin-8-yl)methyl 4-bromophenylcarbamate'
_space_group_crystal_system      monoclinic
_space_group_IT_number           4
_space_group_name_Hall           'P 2yb'
_space_group_name_H-M_alt        'P 1 21 1'
_symmetry_space_group_name_Hall  'P 2yb'
_symmetry_space_group_name_H-M   'P 1 21 1'
_atom_sites_solution_hydrogens   mixed
_audit_creation_method           SHELXL-2016/6
_cell_angle_alpha                90
_cell_angle_beta                 106.7510(10)
_cell_angle_gamma                90
_cell_formula_units_Z            4
_cell_length_a                   12.8335(5)
_cell_length_b                   11.8956(5)
_cell_length_c                   12.9307(5)
_cell_measurement_reflns_used    9873
_cell_measurement_temperature    173(2)
_cell_measurement_theta_max      28.19
_cell_measurement_theta_min      2.37
_cell_volume                     1890.26(13)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX3'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'X-Seed (Barbour 2001)'
_computing_structure_refinement  'SHELXL-2016/6 (Sheldrick, 2016)'
_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
_diffrn_ambient_temperature      173(2)
_diffrn_measured_fraction_theta_full 0.998
_diffrn_measured_fraction_theta_max 0.997
_diffrn_measurement_device_type  'Bruker APEX-III CMOS detector'
_diffrn_measurement_method       'phi and omega scans'
_diffrn_radiation_type           MoK\a
_diffrn_radiation_wavelength     0.71073
_diffrn_reflns_av_R_equivalents  0.0389
_diffrn_reflns_av_unetI/netI     0.0564
_diffrn_reflns_Laue_measured_fraction_full 0.998
_diffrn_reflns_Laue_measured_fraction_max 0.997
_diffrn_reflns_limit_h_max       17
_diffrn_reflns_limit_h_min       -17
_diffrn_reflns_limit_k_max       15
_diffrn_reflns_limit_k_min       -15
_diffrn_reflns_limit_l_max       17
_diffrn_reflns_limit_l_min       -17
_diffrn_reflns_number            28777
_diffrn_reflns_point_group_measured_fraction_full 0.994
_diffrn_reflns_point_group_measured_fraction_max 0.993
_diffrn_reflns_theta_full        25.000
_diffrn_reflns_theta_max         28.391
_diffrn_reflns_theta_min         2.610
_diffrn_source                   microfocus
_exptl_absorpt_coefficient_mu    2.195
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   SADABS
_exptl_crystal_colour            colorless
_exptl_crystal_density_diffrn    1.438
_exptl_crystal_description       block
_exptl_crystal_F_000             848
_exptl_crystal_size_max          0.450
_exptl_crystal_size_mid          0.340
_exptl_crystal_size_min          0.320
_exptl_transmission_factor_max   0.495
_exptl_transmission_factor_min   0.412
_refine_diff_density_max         0.438
_refine_diff_density_min         -0.452
_refine_diff_density_rms         0.070
_refine_ls_abs_structure_details
;
 Flack x determined using 3415 quotients [(I+)-(I-)]/[(I+)+(I-)]
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
;
_refine_ls_abs_structure_Flack   0.022(4)
_refine_ls_extinction_method     none
_refine_ls_goodness_of_fit_ref   0.994
_refine_ls_hydrogen_treatment    mixed
_refine_ls_matrix_type           full
_refine_ls_number_parameters     461
_refine_ls_number_reflns         9413
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      0.994
_refine_ls_R_factor_all          0.0407
_refine_ls_R_factor_gt           0.0317
_refine_ls_shift/su_max          0.002
_refine_ls_shift/su_mean         0.000
_refine_ls_structure_factor_coef Fsqd
_refine_ls_weighting_details
'w=1/[\s^2^(Fo^2^)+(0.0219P)^2^] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0631
_refine_ls_wR_factor_ref         0.0655
_reflns_Friedel_coverage         0.902
_reflns_Friedel_fraction_full    0.990
_reflns_Friedel_fraction_max     0.989
_reflns_number_gt                8225
_reflns_number_total             9413
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            ol6b03605_si_002.cif
_cod_data_source_block           DK-KS-Q87
_cod_database_code               1544946
_shelx_shelxl_version_number     2016/6
_shelx_estimated_absorpt_t_min   0.438
_shelx_estimated_absorpt_t_max   0.540
_shelx_res_checksum              35031
_shelx_hkl_checksum              50847