Enantioselective total synthesis of (+)-arborescidine C and related tetracyclic indole alkaloids using organocatalysis.
Sheth, Vishal M.; Hong, Bor-Cherng; Lee, Gene-Hsiang; Organic & biomolecular chemistry 15 (2017) 3408–3412; doi:10.1039/c7ob00473g

data_7155612
_publ_section_title
;
 Enantioselective total synthesis of (+)-arborescidine C and related
 tetracyclic indole alkaloids using organocatalysis.
;
_journal_issue                   16
_journal_name_full               'Organic &amp; biomolecular chemistry'
_journal_page_first              3408
_journal_page_last               3412
_journal_paper_doi               10.1039/c7ob00473g
_journal_volume                  15
_journal_year                    2017
_chemical_absolute_configuration ad
_chemical_formula_sum            'C16 H20 N2 O'
_chemical_formula_weight         256.34
_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   geom
_audit_creation_method           SHELXL-2014/7
_audit_update_record
;
2016-12-21 deposited with the CCDC.
2017-03-29 downloaded from the CCDC.
;
_cell_angle_alpha                90
_cell_angle_beta                 96.4248(6)
_cell_angle_gamma                90
_cell_formula_units_Z            2
_cell_length_a                   8.1090(2)
_cell_length_b                   9.1450(2)
_cell_length_c                   9.2939(2)
_cell_measurement_reflns_used    8704
_cell_measurement_temperature    200(2)
_cell_measurement_theta_max      70.18
_cell_measurement_theta_min      4.79
_cell_volume                     684.88(3)
_computing_cell_refinement       'Bruker SAINT'
_computing_data_collection       'Bruker APEX3'
_computing_data_reduction        'Bruker SAINT'
_computing_molecular_graphics    'Bruker SHELXTL'
_computing_publication_material  'Bruker SHELXTL'
_computing_structure_refinement  'SHELXL-2014/7 (Sheldrick, 2014)'
_computing_structure_solution    'SHELXS-97 (Sheldrick 2008)'
_diffrn_ambient_temperature      200(2)
_diffrn_measured_fraction_theta_full 1.000
_diffrn_measured_fraction_theta_max 1.000
_diffrn_measurement_device_type  'Bruker D8 VENTURE'
_diffrn_measurement_method       '\f and \w scans'
_diffrn_radiation_type           CuK\a
_diffrn_radiation_wavelength     1.54178
_diffrn_reflns_av_R_equivalents  0.0123
_diffrn_reflns_av_unetI/netI     0.0190
_diffrn_reflns_Laue_measured_fraction_full 1.000
_diffrn_reflns_Laue_measured_fraction_max 1.000
_diffrn_reflns_limit_h_max       9
_diffrn_reflns_limit_h_min       -9
_diffrn_reflns_limit_k_max       11
_diffrn_reflns_limit_k_min       -11
_diffrn_reflns_limit_l_max       11
_diffrn_reflns_limit_l_min       -11
_diffrn_reflns_number            4672
_diffrn_reflns_point_group_measured_fraction_full 0.997
_diffrn_reflns_point_group_measured_fraction_max 0.993
_diffrn_reflns_theta_full        67.679
_diffrn_reflns_theta_max         69.997
_diffrn_reflns_theta_min         4.788
_exptl_absorpt_coefficient_mu    0.614
_exptl_absorpt_correction_T_max  0.7533
_exptl_absorpt_correction_T_min  0.5807
_exptl_absorpt_correction_type   multi-scan
_exptl_absorpt_process_details   'SADABS (Bruker, 2016)'
_exptl_crystal_colour            colourless
_exptl_crystal_density_diffrn    1.243
_exptl_crystal_description       needle
_exptl_crystal_F_000             276
_exptl_crystal_size_max          0.333
_exptl_crystal_size_mid          0.096
_exptl_crystal_size_min          0.074
_refine_diff_density_max         0.167
_refine_diff_density_min         -0.130
_refine_diff_density_rms         0.031
_refine_ls_abs_structure_details
; 
 Flack x determined using 1166 quotients [(I+)-(I-)]/[(I+)+(I-)] 
 (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259). 
;
_refine_ls_abs_structure_Flack   0.05(6)
_refine_ls_extinction_coef       0.0119(13)
_refine_ls_extinction_expression Fc^*^=kFc[1+0.001xFc^2^\l^3^/sin(2\q)]^-1/4^
_refine_ls_extinction_method     'SHELXL-2014/7 (Sheldrick 2014'
_refine_ls_goodness_of_fit_ref   1.045
_refine_ls_hydrogen_treatment    constr
_refine_ls_matrix_type           full
_refine_ls_number_parameters     175
_refine_ls_number_reflns         2573
_refine_ls_number_restraints     1
_refine_ls_restrained_S_all      1.045
_refine_ls_R_factor_all          0.0258
_refine_ls_R_factor_gt           0.0254
_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^)+(0.0358P)^2^+0.1043P] where P=(Fo^2^+2Fc^2^)/3'
_refine_ls_weighting_scheme      calc
_refine_ls_wR_factor_gt          0.0657
_refine_ls_wR_factor_ref         0.0662
_reflns_Friedel_coverage         0.862
_reflns_Friedel_fraction_full    0.993
_reflns_Friedel_fraction_max     0.986
_reflns_number_gt                2546
_reflns_number_total             2573
_reflns_threshold_expression     'I > 2\s(I)'
_cod_data_source_file            c7ob00473g2.cif
_cod_data_source_block           ic18036
_cod_database_code               7155612
_shelx_shelxl_version_number     2014/7
_shelx_estimated_absorpt_t_min   0.822
_shelx_estimated_absorpt_t_max   0.956
_shelx_res_checksum              47966